WASTE REDUCTION STRATEGIES FOR FIBERGLASS FABRICATORS. David R. Hillis ECU, Department of Industrial Technology

Transcription

1 WASTE REDUCTION STRATEGIES FOR FIBERGLASS FABRICATORS David R. Hillis ECU, Department of Industrial Technology A. Darryl Davis ECU, School of Industry and Technology Funding provided by Office of Waste Reduction North Carolina Department of Environment, Health, and Natural Resources

2 Waste Reduction Strategies For Fiberglass Fabricators David R. Hillis ECU, Department of Industrial Technology A. Darryl Davis ECU, School of Industry and Technology Funding provided by Office of Waste Reduction North Carolina Department of Environment, Health, and Natural Resources

3 Reprinted by: Division of Pollution Prevention and Environmental Assistance (formerly OWR) P.O. Box Raleigh, NC copies printed on recycled paper at a cost of $ or $2.27 each.

4 Acknowledgments and Notice Sincere appreciation is expressed to the following individuals who have provided support in the development of this manual: Gary Hunt, Office of Waste Reduction; Sarah McPherson, proofreader, Greenville, NC; Doris Hunt, Secretary, East Carolina University School of Industry and Technology; Robert L. Cottrell, President of Arjay Technologies, Inc.; Doug Hoffman, Grady-White Boats, Greenville NC; and Bob Arthur, Hatteras Yachts, High Point, NC. Special thanks is extended to Dr. Celeste Winterberger, Department of Industrial Technology, East Carolina University, for contributing the chapter on Strategies For Working With Hazardous And Toxic Materials and to Dr. James P. Kohn for his work on styrene testing. Every effort has been made to insure that information provided in this manual is accurate. However, neither the Authors or East Carolina University takes responsibility for the information contained in this manual. No endorsements are provided or implied for the services or products provided by any companies or individuals mentioned in this publication. Comments which can improve the accuracy or usefulness of this manual are welcomed by the senior author and by the Office of Waste Reduction. David R. Hillis Department of Industrial Technology School of Industry and Technology East Carolina University Greenville, NC (919) (919) 32% 4250 Gary Hunt, Director Office of Waste Reduction Department of Environment, Health, and Natural Resources l? 0. Box Raleigh, NC (919) FAX (919) Acknowledgments and Notice Page i

5 i.>:, -, 0 / ] / I I Table of Contents Introduction Acknowledgments and Notice Table of Contents Preface Glossary i vii... Vlll Chapters I An Overview of the Industry The Industry and Products Lamination Methods and Processes Establishing Pollution Reduction Strategies II Are Pollution and Waste Reduction Strategies Necessary? Profitability in Waste Reduction Governmental Incentives Regulatory Factors in Planning for Waste Minimization Regulated Requirements Regulated Materials Environmental Impact Work Environment and Worker Protection Liability and Legal Concerns Limiting Legal Liability Legal and Regulatory Barriers The Need for Change and the Change Process Success and Change Starting the Change Process Determining the Starting Point for Change The Change Process III Strategies For Working With Hazardous and Toxic Materials By Celes te Winterberger Introduction 21 Definition of Terms, 21 Regulations Resource Conservation and Recovery Act (RCRA) 23 National Pollution and Discharge Elimination System (NPDES) 25 The Federal Water Pollution Control Act 27 The Clean Air Act 27 The Hazardous Materials Transportation Act (HMTA) 29 Employee Training 29 Table of Contents Page iii

6 i I Hazard Communication 31 Emergency Planning and the Community Right to Know 32 Conclusion 32 IV Production-Based Pollution Reduction Strategies Introduction Wet-Out Methods Using Spray Conventional Spray Guns Airless Spray Guns Air Assisted Airless Guns High Volume Low Pressure (HVLP) Spray Combining Reinforcement with Resin Spraying Lay-Up Liquid Wet-Out Methods Prepreg Fiber Reinforcing In-House Resin Impregnation Resin Rollers - Spray-Less Application Systems Vacuum Bag Molding Vacuum Bag Molding Processes Infusion Infusion with a Semi-Rigid Cover Resin Transfer Molding (RTM) Rotational Molding, Examining Thermoplastic Options Rotational Molding of Small Tanks Combining Subassemblies to Minimize Waste Materials Low Emission Resins - Additives Catalysts Benzoyl Peroxide W Curing Resins Low Styrene Resins Resin Storage Resin Circulation System V Managing Contaminated Solvents Solvent Use Alternatives to Acetone In-Plant Solvent Recovery Continuous Feed Distillation Equipment Out-of-Plant Solvent Recovery Incineration of Contaminated Solvents Table of Contents Page iv

7 VI Management and Facility-Based Pollution Reduction Strategies Process Control Strategies Plant Layout - Localizing and Isolating Problem Operations Isolating Problem Areas Confining Gel Coat Applications Approaches to Gel Coat Isolation Approaches to Isolating Other Operations Appendices Air Filtration and Recirculation Systems Filtering Contaminated Air Dry Filtration and Recirculation Wet Filtration Systems Fume Incineration, Burning Styrene Emissions Controlling Air-Flow and Exhaust Exhaust Ventilation Maintaining Positive Pressure Local Exhaust A. B. C. D. A Case Study in Waste Reduction and Profitability North Carolina - Department of Environmental, Health, and Natural Resources Map of Regional Offices Suppliers of Equipment and Services Processing Equipment Suppliers Suppliers of Distillation Equipment Hazardous Waste Services Hazardous Waste Transporters North Carolina Quality Leadership Award Case Studies High Volume Low Pressure (HVLI?) Spray Guns, Hatteras Yachts, High Point, NC Venus Resin Impregnator Syntechnics, Inc., Paducah, KY Resin Roller Ajay Technologies, Largo, FL Comparison of Resin Spray to Resin Rollers Grady-White, Greenville, NC Vacuum Bag Molding Fountain Powerboats, Washington, NC Infusion with Resin Injection Recirculation Method (RIRM) Structural Composites, Melbourne, FL Table of Contents Page v

8 I i t. 7. Resin Transfer Molding Hatteras Yachts, High Point, NC 8. Composite Preform System Structural Composites, Melbourne, FL 9. UV Cured Resin International Marine, Miami, FL 10. Mini-Bulk Resin Storage System Warren Wilkerson, Belhaven, NC 11. Acetone Replacement in a Fiberglass Laminating Operation Carolina Classic, Wilson, NC 12. In-Plant Batch Distillation Unit Fountain Powerboats, Washington, NC 13. Supplier-Based Solvent Recovery Hatteras Yachts, New Bern, NC 14. Plant Air Recirculation System S2 Yachts Holland, MI 15. Incineration System for Styrene Emissions, Lasco Bath Fixtures, South Boston, VA Table of Contents Page vi

9 Preface Eight years ago the manual, Pollution Reduction Strategies in the Fiberglass BoafbuiZding and Open Mold Plastics Industries, was published. The intent of the authors was to provide practical information on reducing waste and pollution in fiberglass laminating operations. That manual was well received by manufacturers in the industry. However, over the past eight years technology, practice, and regulations have changed. Therefore, much of the content in the original manual needed to be reviewed and brought up to date. Funding for the project to revise and update the manual has been provided by a grant from the Office of Waste Reduction, North Carolina Department of Environment, Health, and Natural Resources. Mr. Gary E. Hunt, Director of the Office of Waste Reduction, and other members of his staff have also provided substantial support in reviewing and commenting on the content of the manual. Concentrating on boatbuilding and open molding was considered important since manufacturers in this industry use large quantities of liquid resins and solvents that have the potential to produce considerable quantities of airborne pollution and contaminated solid waste. Open mold fabricators utilize a number of materials and processing methods which make knowledge of environmental regulations and appropriate waste management strategies essential to the survival of their companies. The materials used include styrene based polyester resins, methyl ethyl ketone peroxides, acetone, and other solvents and specialty chemicals. Since resins are often applied through an atomization process, air quality in and outside the facility is a major concern. Attention must also be focused on the entire manufacturing cycle which begins with product design and materials selection and continues even after waste disposal. The contents of this manual touch on the major aspects of this cycle. The information presented comes from a number of sources. Federal and state regulations were reviewed, and interviews with individuals from state and federal agencies were also conducted to supplement our understanding. Much of the technical content was developed as result of numerous in-plant visits and observations as well as telephone interviews with a number of fiberglass fabricators. Firms engaged in production and marketing of processing equipment and supplies for the industry also provided valuable information and many useful leads. Preface Page vii

10 Glossary Every industry has its own terms and jargon which become part of the language of those who work in or serve that industry. The fiberglass boat building and,open mold plastics industry is no exception. The following defines some of the key terms used in this industry. Catalyst In fiber reinforced plastics the catalyst is the substance added to the gel coat or resin to initiate the curing process. The catalyst usually oxidizes an accelerator creating free radicals which cause the resin or gel coat to polymerize or cross-link. Closed Molding A molding process using two matched molds. This method of molding reinforced plastic provides a good inside and outside surface. This type of mold tooling is much more expensive than open mold tooling. curing FRP Gel Coat Hand Lay-up A polymerization process transforming the liquid resin to a solid creating the maximum physical properties attainable from the materials. The initials of fiber reinforced plastics. A colored resin used as a surface coat for molded fiberglass products. It provides a cosmetic enhancement and environmental protection for the fiberglass laminate. Placing reinforcement materials and resin onto a mold by hand. The resin application is frequently accomplished with a spray gun. Open Molding An open mold provides a finished and dimensional accurate surface upon which the lay-up can be placed. Gel coat is usually is sprayed first on the prepared surface of the mold. The reinforcement materials are applied on top of the gel coat. This form of molding provides one finished side. Resin Styrene Wet-Out A class of organic products either natural or synthetic in origin, generally having high molecular weight. Most uncured resins used in open molding are liquids. Generally resins are used to surround and hold fibers. When catalyzed, the resin cures going through a polymerization process transforming the liquid resin into a solid. The cured resin and reinforcement creates a composite material with mechanical properties-that exceed those of the individual components. An unsaturated hydrocarbon used in plastics. In polyester resin it serves as a solvent and as a co-reactant in the polymerization process that occurs during curing. Saturating reinforcing material (glass fiber) with resin. The rate or speed of saturation is a key factor in effective and profitable molding. Glossary Page viii

11 The Industry and Products- CHAPTER I An Overview of the Industry Open molding or laminating of thermosetting plastics is a primary manufacturing process carried out in a variety of North Carolina firms. Also, many companies use open molding as an adjunct process to produce accessories or components for more complex products which are assembled in their facilities. Open molding, consequently, is a key process that contributes valuable products as well as several thousand jobs throughout North Carolina. The firms involved in lamination range from companies employing only one or two people to internationally recognized organizations which employ more than 1,000 people. However, most of these firms are small companies with fewer than 100 people involved in daily plant operations. The product most commonly associated with resin lamination is the fiberglass boat. There are, according to the US Coast Guard, approximately 70 to 75 fiberglass boat builders in North Carolina. Their products range from small creek boats to yachts as large as 130 feet. There are, of course, many other applications for open molding. The traditional fine wood and upholstered furniture industry in the state has expanded to include the development of production facilities for molded furnishings ranging from restaurant seating fixtures to lawn and garden furniture. An expanding demand for durable fixtures and corrosion resistant industrial equipment is also contributing to the growth of open molding operations involved in producing such specialty products as cultured marble bath fixtures, bathtubs, large storage tanks, truck body components, architectural panels, heat exchanger components, floating pier modules, and machinery housings. Plants involved in laminating are locating in all geographic regions of the state. The State s moderate climate is well suited to the requirements for processing thermosetting plastics such as polyesters. Since many open molding firms are already located in the state, a good network of equipment and material suppliers is already well established. Because of these resources and the experienced work force, North Carolina should continue to attract and support open molding industries. North Carolina also has an excellent market for many of the goods produced by the industry. The state is geographically situated so that shipment of products to the heavily populated Northeast and the rapidly growing Southeast is relatively fast and inexpensive. Access to water is also important to boat manufacturers who must ship finished yachts that are too large to transport by truck or rail. Open molding is particularly useful for highly engineered products designed to meet a variety of application demands, particularly when requirements include United States Coast Guard Marine Safety Office, Wilmington, North Carolina. Chapter I Page 1

12 high strength, low weight, environmental stability, corrosion resistance, weather resistance, or long life. The industry will continue to experience continued demand for highly engineered products since start-up costs and product modifications are less expensive and require less lead-time than other basic types of material processing. For products with complex shapes and limited productivity the investments required for facilities, tooling, and equipment is low enough to attract the interest of large and small firms. Lamination Methods and Processes Al though the composition, shape, and size of open molded products can vary significantly, the basic fabrication requirements change very little. To create products with a smooth durable finish requires a female mold which is smooth and highly polished. The mold is cleaned and coated with a release agent such as wax or a polymer coating. The first step of the lamination process begins with the application of a gel coat resin (see Figure l-l). Polyester resins are used in most gel coats and for most lay-ups (refer to the glossary. Currently the majority of production systems deliver resin through spray guns. These guns spray the 4 resin and catalyst separately and therefore rely on the turbulence of the spray pattern to mix the resin and catalyst. In some cases short chopped fibers are also introduced into the spray pattern with the resin and catalyst. In large parts where structural strength is critical, fiber reinforcing in sheets are used instead of the chopped fibers. These sheets are placed in the mold and sprayed with catalyzed resin. Once the reinforcement is in place, hand rolling is almost essential for removing voids, smoothing the surface, and insuring proper integration of resin and reinforcing material. Fiber Reinforcement & Resin Gel Coat Sprayed On Mold Surface FIGURE l-l. Open mold configuration. Chapter I Page 2

13 Physical plant arrangements for most small producers consist of one or more open production areas. In these areas the entire lamination process is carried out along with resin spraying. Styrene, the principle volatile organic compound (VOC) in polyester resin, is normally controlled through the use of a number of exhaust fans. This production process leads to several potential pollution problems in terms of airborne solids, over spray, and styrene vapor emissions. Even when good exhaust systems are provided, there can be expensive problems for the producer. In many cases, air flow patterns are such that relatively clean plant air is exhausted while a poor job is done in ventilating areas where air contamination remains high. Current methods also present open molders with other potential pollution and safety problems in terms of storing hazardous materials, disposing of contaminated solvents and waste disposal, handling highly flammable liquids and vapors, and controlling dust. There are many variations in processing in the industry because of the diversity of products produced. Methods used for molding a cultured marble bathroom counter and sink are different from the approaches used to mold a fiberglass boat hull. Basically similar products can also be produced using significantly different methods and techniques because of differences in facilities and the organization s production concepts. Where high production outputs are required, larger companies can invest in more complex tooling and equipment for each unique operation thereby improving quality and reducing labor content. Smaller organizations frequently are forced to perform a variety of operations using simple labor intensive methods within the same production area. In fact, most small operations are set up in open general purpose structures with little regard for anything other than basic lay-up and secondary finishing. Specialty equipment, engineered facilities for specific operations, formal training programs, and a management focus on waste reduction are frequently beyond the capability of these smaller firms. Consequently, these companies need access to strategies that integrate good business practice and appropriate manufacturing technology to achieve waste reduction in a manner that maintains their ability to compete effectively. Although no one approach is appropriate for all firms, it is possible to develop a strategy by selecting and blending appropriate techniques developed by others. Establishing Pollution Reduction Strategies Because of the nature of the materials used in creating laminates, the industry is being forced to increase its emphasis on safety and pollution prevention issues. Also federal and state regulations are becoming more stringent and are identifying more materials which will require new approaches for managing their use and disposal. Worker safety is also an important issue for management. Consequently, pollution prevention and waste reduction strategies are generally an outgrowth of problems created by these regulatory and enforcement demands. Managers, therefore, need to be aware of these regulations and health standards as well as the manufacturing technologies available, when they select materials for processing and develop production processes. The prospects for the industry to effectively meet these current and Chapter I Page 3

14 new regulations and standards are good. In fact, many producers have found that some pollution prevention and waste reduction methods are actually cost effective. A number of these techniques are reviewed in this manual. In establishing a waste reduction strategy, a firm must be willing to take an overall approach as well as a long term view of managing resources. In many cases the approaches to facility and process development in the open molding industry can be categorized as being shortsighted or simply staying with past practice out of habit. Profitable pollution prevention approaches are developed when careful attention is paid to using best manufacturing practices that include minimizing variation, refining material flow patterns, conserving materials and utilities, separating incompatible operations, and instituting inventory control procedures. Therefore, it is possible that pollution related problems can be minimized through facilities design with a view towards future needs and regulatory demands. Planning ahead will be essential to the survival of the industry. The materials used in the open molding process are under constant scrutiny by health and, environmental agencies. There seems to be little doubt that future regulations regarding in-plant and out-of-plant air quality, worker exposure, and waste storage and disposal will get tougher. Processing equipment and facility designs should be selected with potentially tougher regulations in mind. Where possible, alternate materials and processing approaches should be explored to eliminate or reduce the problems created by the use of hazardous materials. At a minimum, existing facilities and equipment should be fine tuned to bring potential environmental problems under control. Chapter I Page 4

15 CHAPTER II Are Pollution and Waste Reduction Strategies Necessary? Profitability in Waste Reduction The work required to maintain a profitable business in the open molding industry is complicated by the need to cope with a number of potential worker safety and environmental pollution problems. Management and investors frequently view compliance with pollution regulations and workplace safety requirements as efforts that do not add value to the product or improve productivity. There is little doubt that strict environmental regulations have resulted in costly changes to basic production techniques, the purchase of specialty equipment for pollution reduction, and the adoption of management strategies that are not entirely production centered. However, there are many instances where environmentally sound approaches for processing with hazardous materials do lead to cost savings. A number of the case studies and examples included in this manual demonstrate that pollution prevention and waste reduction strategies do not always have a detrimental effect on profits and productivity. In some cases pollution prevention strategies have provided a substantial return on investment and have actually increased profits. An example is the case study reported in Appendix A. When calculating the overall effects of implementing a pollution prevention and waste reduction strategy, it is often difficult to get a clear picture of the actual costs and benefits of all available alternatives. A complete picture requires management to consider all the factors that go into a profit and loss statement in order to evaluate a strategy properly. Management s goal in this analysis should be to select a waste reduction strategy that has a value added instead of a cost increasing approach to compliance. This comprehensive approach is generally termed Ire-engineering the business. The end result will make the organization a stronger competitor able to work within the appropriate regulations. This approach sounds fine, but manufacturers know that developing a profitable strategy will take time, knowledge, money, and some outside support. Fortunately, there are some resources available. Governmental Incentives A number of incentives for implementing pollution prevention strategies are provided by the State of North Carolina, the Federal Government, local governments, and private agencies. 0 Incentives are offered by the State and Federal Government to: Help complying companies by insuring that non-complying companies do not enjoy a competitive advantage over complying companies; Chapter II Page 5

16 c a 2) 3) Provide relief to industries forced to implement expensive changes in order to comply with pollution or cleanup requirements; and Encourage compliance with state and federal. pollution abatement requirements. Selected North Carolina incentives currently in existence include: 1) Special tax treatment for recycling and resource recovery operations can reduce or eliminate portions of: Real and personal property tax, Corporate state income tax, Franchise tax on domestic and foreign corporations. 2) 3) For more information about special tax treatment for recycling and resource recovery operations contact your county tax assessor s office. You can also obtain information from the area supervisors of the Solid Waste Section of the NC Department of Environmental, Health and Natural Resources. The Eastern area sudervisor is at 225 Green St., Suite 601, Fayetteville, NC 28301, (910) The Western area sunervisor is at 8025 North Point Blvd., Winston-Salem, NC 27106, (910) Tax Exempt Industrial Development and Pollution Control Bonds are available if they meet certain criteria and are approved by appropriate local and state authorities. Contact your regional supervisor for the Department of Environmental, Health, and Natural Resources Division of Environmental Management. Appendix B shows the seven regions in North Carolina. Demonstration projects for manufacturers initiating, expanding, or converting to the use of recycled feed stock have been established. During the FY the state will fund four projects in amounts up to $20,000. Additional information on current programs and awards can be obtained from: NC Recycling and Reuse Business Assistance Center, Office of Waste Reduction, 3825 Barrett Dr., 3rd Floor, Raleigh, NC 27609, (919) A listing of other programs that may offer tax and state incentives for pollution abatement equipment can be obtained from Bill Meyer, Division of Solid Waste Management, North Carolina Department of Environment, Health, and Natural Resources, Box 2091, Raleigh, NC 27602, (919) Chapter II Page 6

17 0 Other 4) Challenge grants for pollution prevention are being offered by the North Carolina Pollution Prevention Program. a This program has been in operation since 1984 and has funded over 100 projects. Approved projects can receive. up to $15,000. More information can be obtained from: potential incentives include: 1) 2) Program Manager, Pollution Prevention Program, Office of Waste Reduction, 3825 Barrett Dr., 3rd Floor, Raleigh, NC 27609, (919) Incentives offered by local governments or industrial development agencies for the purpose of attracting or retaining industries. Public recognition that enhances the status of the company in the eyes of the community and customers. One example of this type of incentive is the Governors Award for Excellence in Waste Reduction. This award has been given for the past twelve years to industries who have demonstrated excellence in eliminating and reducing waste. Eljer Industries (now Carolina Classic), a fiberglass tub manufacturer in Wilson North Carolina won this award in 1990 for replacing acetone with a water-based cleaner. 3) Limiting unforeseen long-term liabilities. Incentives are constantly changing. Information should be sought from local agencies, state governmental agencies, federal agencies, tax specialists, and suppliers of pollution reduction equipment and services. Industry associations such as the North Carolina Marine Trade Association can be of help in identifying incentives and resources available to composite fabricators. You can reach the North Carolina Marine Trade Association at: North Carolina Marine Trade Association, UNCW, Westside Hall, 601 South College Road, Wilmington, NC Regulatory Factors in Planning for Waste Minimization Currently North Carolina, along with approximately one-third of all other states in the United States, has laws requiring companies to do some form of pollution prevention planning. In 1989, the North Carolina General Assembly enacted legislation requiring all persons holding air quality, wastewater pretreatment, hazardous waste generation, and/ or stormwater discharge permits to submit with their payment of annual fees a written description of their current plans to reduce waste. As of 1994 the state has implemented these requirements for pollution prevention in the permitting process. Chapter II Page 7

18 In 1993 the state established a Pollution Prevention Advisory Council. This council has recommended: Pollution prevention planning for certain industrial facilities and state agencies; A statewide pollution prevention goal; An incentive program to encourage North Carolina waste generating facilities to incorporate pollution prevention into their business operations; A comprehensive program to educate children, the general public, and industry about pollution prevention. Waste minimization programs are also being implemented or revised by the US. EPA. Information on waste minimization planning can be obtained from the Office of Waste Reduction, (919) This office is able to provide guidance on waste minimization programs, on-site waste reduction assessments, and the current status of waste reduction goals and requirements. Regulatory Requirements 4 As most manufacturers know, there are many local, state and federal regulations covering environmental and safety issues. According to the code of federal regulations, all industrial installations are legally obligated to properly handle, ship, store, and dispose of hazardous materials and waste. In addition, there are regulations specifically issued for the protection of employees in the workplace. A few important regulations are listed in Table 2-l. A more complete description of these requirements can be found in Chapter III. TABLE 2-1. Pollution and safety related regulations. D Occupational Safety and Health Administration (OSHA) Major Programs Permissible exposure limits (PELs) Medical surveillance programs for substance-specific standards Ergonomics safety and health standards Respiratory protection Powered industrial trucks Confined space entry Face, head, eye, and foot protection Employee training in safety and health 0 Environmental Protection Agency (EPA) Major Programs Clean Air Act, the 1993 compiled version (includes amendments) Storm-water Regulations of 1990 Pollution Prevention Act of 1990 (WA), public information on current practices and projections of activities involving chemical waste Resource Conservation and Recovery Act (RCRA) Emergency Planning and Community Right to Know Act (EPCRA) Chapter II Page 8

19 Regulated Materials Chemical control, use, and tracking are key parts of the government s approach to protecting the environment and human health. The federal and state governments have several agencies to enforce the attendant regulations. Chapter III explains many of the regulations and responsibilities that manufacturers must accept to be in compliance. One of these responsibilities is knowing and making all your employees aware of the nature of the materials that are used in the business. You ll have to ask your suppliers to identify and provide Material Safety Data Sheets for all the materials you purchase. Knowing what materials are regulated by governmental agencies, the regulation under which the materials are governed, and the material s permissible use are essential components for formulating a workable strategy for waste reduction. Although the fiberglass molding industries rely on sophisticated chemical processes to fabricate their products, these processes involve only a small number of materials with the potential to be hazardous to human health or to the environment. A brief description of the most important chemicals follows. Styrene Styrene is a colorless liquid with a sweet aromatic odor at low concentrations. At higher concentration, the odor becomes sharp and disagreeable. Styrene vapor is 3.5 times heavier than air. The flash point of styrene is 88 F. The lower explosive limit is 1.1% and the upper limit is 6.1% by volume. If a polymerization inhibitor is not present in sufficient concentration, styrene can polymerize and explode in its container. Styrene will corrode copper and is not compatible with oxidizing agents, strong acid, and catalysts for vinyl polymers. Styrene affects the central nervous system. It can also cause other conditions such as peripheral neuropathy, skin disease, and abnormal pulmonary function. It may be considered to be liver toxic, teratogenic, and carcinogenic. Methyl Ethyl Ketone Peroxide Methyl ethyl ketone peroxide (MEKP) is the most popular catalyst in use in the industry. It is a clear colorless liquid with a slightly pungent odor and is a potential explosive hazard. MEKP has a flash point of 185O F. It is incompatible with very strong acids, bases, and oxidizers. It is an irritant for the skin and nose and can cause blindness. It also affects the lungs and central nervous system. Benzoyl Peroxide Benzoyl Peroxide (BPO) has been used for years as a catalyst for curing unsaturated polyester and vinyl ester resins at elevated temperatures. The catalyst is available in granular and wet forms. When diluted, the mixture contains between 50 to 85% BPO. Aqueous forms of BP0 are commonly used since this form reduces the explosive and fire hazards that exist with Chapter II Page 9

20 the pure powder. The paste is also an easier form to use. At room temperature BP0 will slowly react with unaccelerated resins. The accelerators normally added to polyester resin for MEKP are not effective with BPO, therefore users will have to ask their resin suppliers for recommendations for a suitable replacement. Users report that BP0 appears to have some effect in suppressing styrene emissions. Acetone Acetone is used as a general solvent for cleaning purposes. It is a colorless liquid with a fragrant, mint-like odor..acetone has a flash point of 15 F, and it is incompatible with acids and oxidizing materials. Acetone is an irritant for the eyes, nose, throat, and skin. It is also a central nervous system depressant. During the later part of 1994 there was some discussion concerning the removal of acetone from the list of chemicals classified as VOCs. Regardless of the outcome, acetone will still be classified as a hazardous material. Environmental Impact Virtually any application of science and technology in manufacturing can produce wastes and pollutants. Without proper control and treatment, these materials are a threat to the continued survival of the animal and plant communities of the ecosystem. Eventually, they may also threaten the existence of the human community. For a conscientious company, environmental concerns should be a part of the day-to-day operation of the business. This is especially true with respect to the discharge of pollutants into the air or nearby rivers and streams. In addition, proper disposal of waste on the land should also be assured. Because air pollution, water pollution, and the accumulation of hazardous and toxicwaste have created conditions which have adversely affected environmental quality, federal and state governments have promulgated regulations for the prevention of environmental degradation. A severe penalty and possible imprisonment can be imposed under these regulations. The state agency which is responsible for the enforcement of environmental legislation in North Carolina is the North Carolina Department of Environment, Health, & Natural Resources (Figure 2-l shows the departments within this agency). The laws are listed in North Carolina Environmental Management Laws, which was issued by the above mentioned Department (Publisher: The Michie Company, Charlottesville, VA). Work Environment and Worker Protection The issues of environmental quality impact our work environment as well as our natural environment. Because the emphasis on worker protection is different from that of environmental protection, regulation and standards are also different. Consequently, worker health and safety is a critical aspect in the creation of a good work environment. Chapter II Page 10

21 FIGURE 2-l. Agencies within the Department of Environment, Health, & Natural Resources. Chapter II Page 11

22 In the event of an injury an employer is bound by law through worker s compensation to provide the injured employee with a paycheck. The law not only provides work accident victims with reasonable income and benefits, they also encourage employers to reduce work accidents and human suffering. One of the most valuable features of these laws has been that they stimulate efforts to prevent occupational diseases and injuries. Since rates charged for worker s compensation insurance coverage usually depends on the accident history of the company covered, it is profitable for a company to promote worker safety through the establishment of a strong safety program. The next chapter outlines the basics for establishing training and safety programs for handling hazardous and toxic wastes. Liability and Legal Concerns Long-term liability may be the most important factor in the decision making processes related to pollution prevention strategies. This is true when considering worker safety as well as the relationship of materials and processes to the environment. The Resource Conservation and Recovery Act (RCRA) cradle-to-grave philosophy, as well as lawsuits being carried out under the Comprehensive Environmental Response Compensation and Liability Act (Superfund), should attract the attention of management in the open molded plastics industry. Even companies who legally and properly disposed of hazardous waste in the past are now having to absorb cleanup costs for those materials. Lawsuits have forced companies to pay the cost of removing their wastes from licensed landfills and disposing of them in a manner that meets current standards. Hazardous materials and processes create a number of concerns regarding worker health and safety. Existing and emerging regulations must be considered when selecting equipment, designing production processes, and choosing materials. Chemicals used in resins and solvents, along with dust created by grinding operations, make the open molding industry a prime target for lawsuits related to long-term worker health. Limiting Legal Liability The best approach to limiting long-term liability is to avoid using hazardous materials and generating hazardous waste. Operations which do not use these materials have no liability. However in the composites industry this is not likely to happen. Where hazardous materials cannot be eliminated, an affirmative action approach to waste management, air and water discharge, and worker safety is essential to the reduction of long-term legal liabilities. Under present state and federal laws the generator of a hazardous waste is never relieved of the responsibility for that material. Consequently, if production requires the use of hazardous materials, strategies should focus on reducing the volume of those materials needed and minimizing waste. Decreasing the volume will also Chapter II Page 12

23 reduce the magnitude of the long-term liability because environmental effects are frequently related to waste volume. Development of production approaches which can eliminate or substantially reduce the quantity of hazardous materials used or generated as waste is not always possible. If waste cannot be eliminated through source reduction then processes such as in-house recycling should be considered to decrease the liability incurred in disposing of hazardous wastes. Legal and Regulatory Barriers Regulatory agencies and legal statutes provide a number of disincentives for failure to insure worker safety and health and for improper or poor waste management. There are many civil penalties for noncompliance or negligence. In some cases negligent actions or inaction can lead to criminal charges and possible imprisonment. Regulations and penalties as disincentives include policies which prohibit the EPA from approving or recommending to private parties any facilities that have Category 1 violations. North Carolina also follows this procedure. Regulatory policies also require that penalties for noncompliance be large enough to offset any economic gain from noncompliance. Owners or stockholders are directly affected since penalty expenses for violations are not tax deductible. Success and Change The Need for Change and the Change Process The global marketplace has created the need for companies to expand their horizons in defining their markets for - their products as well as assessing the capabilities of the competition. Companies that don t respond to these opportunities and threats may find their business becoming less viable. Industry leaders and the press typically have blamed the high wages paid to American workers for the loss of business to foreign firms. However, many domestic companies have found that they can compete effectively if they are able to provide products of good quality and value. Successful companies have found that providing competitive products means that they must continually assess their operations and be committed to ongoing change. Consequently, change becomes an integral part of doing business. Managing change is not a one-time or occasional thing but is one of the essential ongoing functions of management. The process of assessment and change followed by competitive companies is also effective for developing profitable waste reduction strategies. Starting the Change Process In carrying out change you need to know four things: 1.) Current performance (present status), 2.) A standard of performance (benchmark or regulation), 3.) The proposed goal (new level of performance), 4.) How to get from here to there (a strategy). Chapter II Page 13

24 To start the process you must establish your present status. This assessment requires a careful analysis of current performance. Once this is done, a standard of performance must be obtained for comparison. Next, establish a goal to correct the perceived deficiencies. A deficiency exists when there is a difference between current status and some standard of performance. These standards are based on a benchmark (an internal or external standard) or statutory regulations. In plain terms, current status states levels of performance in units of measure (like delivery time in days, cost of scrap in percent of sales, tons of VOC emissions per year, cubic yards of waste sent to the landfill per month, and so forth). For example, current status for the XYZ Company for styrene emissions may be 12 tons per year (TPY). A regulatory standard may state, A permit is required if you exceed 10 tons per year of any one VOC. A goal would state W e are going to reduce styrene emissions from our curre?l:t status of twelve tons per year to nine tons per year. Goals result from identifying good manufacturing practice which you believe can be applied to your situation. For instance, you may know of a company that changed from external mix spray guns to resin rollers for applying resin to open molds. After the changeover their emissions of styrene went down 25%. Therefore, you establish your goal for the reduction of styrene emissions based on their performance since you believe this technology can also be applied in your business. This method of comparison and goal setting is frequently referred to as benchmarking on good manufacturing practice. In each case the goals resulting from these comparisons should be stated as explicitly as possible and must be clearly communicated to all concerned. If goals are not clear, the probability of successful change is diminished. Determining the Starting Point for Change To determine your company s current status, the identity and magnitude of the waste streams must be resolved. This can be done by analyzing the amount of materials used and the manufacturing methods currently employed. For example, if a company is using a dicyclopentadiene (DCPD) polyester resin with 45% styrene as a material and is applying it to a mold using an external mix high pressure spray gun, it s likely that nearly 10% of the styrene by weight would be lost to the atmosphere. This is approximately 4.5% of the total weight of the resin being used. Therefore, one waste stream could be identified as styrene loss, and an entry to a data sheet would show that 4.5 pounds of styrene would be lost for 100 pounds of polyester resin used. The total purchases of polyester resin in a year less adjustments for inventory would provide an indication of the amount of styrene lost to the atmosphere. Deciding exactly what data to collect and how to tabulate it is the key to determining your current status. A comprehensive approach is needed. In essence, you will need to account for all the material the company buys and how it is used. This may seem to be a daunting task, but the work involved is not overwhelming. If your company has made some studies on waste and scrap, you can use those factors. Otherwise, you ll have to start weighing your product, dumpster, and barrels that you may be shipping off for disposal. The styrene lost Chapter II Page 14

25 to the atmosphere can be estimated using information the EPA has collected on common laminating processes. These factors are shown in Table 2-2. TABLE 2-2. Toxic Air Pollution Emission Factors Taken From A CornDilation For Selected Air Toxic Compounds And Sources, Second Edition, EPA-450/ , October Process *Emission Factor - Styrene Lost Per Pound of Resin Used Resin Characteristic Closed Molding.Ol -.02 lb. Vapor-suppressed resin Closed Molding.Ol -.03 lb. Non-vapor-suppressed resin Continuous Lamination.Ol -.05 lb. Vapor-suppressed resin Continuous Lamination lb. Non-vapor-suppressed resin Hand Lay-up lb. Vapor-suppressed resin Hand Lay-up.05 - JO lb. Non-vapor-suppressed resin Pul trusion.ol -.05 lb. Vapor-suppressed resin Pultrusion lb. Non-vapor-suppressed resin Spray Lay-up.C lb. Vapor-suppressed resin Spray Lay-up lb. Non-vapor-suppressed resin TABLE 2-3. Estimating styrene loss from gel coat spraying. Calculating an Estimate of Styrene Losses from Gel Coat Spraying Styrene loss Percent Styrene Styrene Loss Factor* In Your Mat 1 Per 100 Lbs. Gel Coat Sprayed External mix air spray Low range.054 X ---- = ---- High range s45 X ---- = Airless spray Low range.032 X ---- = High range.llo X ---- = *Based on information from the Polvester Products ADDlications Manual, 7th Edition, 1990, Cook Composite and Polymers Co., Kansas City, MO. Chapter II Page 15

26 Cook Composites and Polymers Company has also conducted tests to determine the amount of styrene loss during gel coat spraying. The results indicate that styrene loss from gel coating using conventional air spray equipment ranges from 5.4% to 14.5 %. With airless spray equipment the range is from 3.2% to 11%. In both cases higher levels of styrene loss occur as the distance between the spray gun and the sprayed surface increases. The spraying distance in the tests ranged from 1.5 feet to 6 feet. A method for using these factors for estimating styrene loss is shown in Table 2-3. To complete the calculation you will need to choose the appropriate type of spray equipment and determine the percent styrene in the gel coat material you are buying. If you don t know the percentage, ask your gel coat supplier for the styrene content in percent by weight. When you have determined the styrene percentage, multiply the appropriate factor by the percent styrene to obtain an estimate of the styrene loss in pounds per 100 pounds of gel coat sprayed. The amount of styrene lost from gel coat spraying is just one source of waste. Other losses need to be estimated in order to get a complete understanding of the wastes coming from the manufacturing system. This number can be obtained through the use of a sources and uses analysis. An example of the categories included in a sources and uses analysis are shown in Figure 2-4. To carry out the analysis requires that the weight of all materials be accounted for during a specific time period. The analysis has three major sections: 1. Total material purchases in pounds -- Sources 2. Total material weight in pounds in completed product -- Profitable Uses 3. Total material weight converted to waste -- Unprofitable Uses An interesting number to calculate is the efficiency factor for your manufacturing system in terms of its ability to convert purchased materials into finished product. Developing a profitable strategy for waste reduction hinges on how close this factor can be brought to one. The calculation is made as follows. Efficiency Factor = Profitable Uses Total Sources To calculate this factor you need to obtain the weight of laminating materials used during a specific time period and the weight of the laminate produced. One manufacturer of fiberglass bathtubs and shower stalls obtains these numbers on a shift by shift basis. The weight of resin used is obtained by measuring how much the resin level has dropped in the storage tank during the shift. The inches of resin used is converted to gallons which in turn is converted to pounds. A similar method is followed to calculate the amount of gel coat used. Solid materials like glass fiber are tracked by counting the number of rolls used during the shift and then calculating the weight. Partial rolls are weighed on scales. The weight of reinforcing materials used are also totaled and recorded. Chapter II Page 16

27 TABLE 2-4. An example of a sources and uses data sheet. SOURCES AND USES DATA COLLECTION SHEET Lamination Process Time period for the Study Beginning Date Ending Date Sources Materials Used during the Period less inventory Adjustments 1. Gel Coat Lbs. 2. Polyester Resin Lbs. 3. Fiber Glass Lbs. 4. Reinforcement Materials Lbs. 5. Acetone Lbs. 6. Other Solvents Lbs. 7. Masking and Covering Materials Lbs. Total Sources Lbs. Profitable Uses -- Weight of all product produced in the period 1. Your Product -- Boat Hulls, Decks, and Other Components (no hardware) Lbs. Unprofitable Uses 1. Solid Waste, Dumpster Lbs. Trimmings Lbs.. cut outs Lbs. Over spray, walls & floors Lbs. 2. Acetone Drummed for Disposal or Distillation Lbs. 3. Acetone Loss (Acetone used - Acetone Drummed) Lbs. 4. Styrene Loss to the Atmosphere Gel Coat loss from Figure 3. Factor X 100 Lbs. of Gel coat = Lbs. Polyester resin used during the period. Factor X Lbs. of Resin = Lbs. Total Unprofitable Uses Lbs. Chapter II Page 17

28 I I And finally, all the weights are added together to obtain the Total Sources weight -- the weight of materials used. To obtain the weight for Profitable Uses this manufacturer totals the weight of each completed tub and stall. The result gives the manufacturer a means to gauge the efficiency of the manufacturing process. The difference between the two numbers provides a good estimate of the magnitude of the total waste being generated by the lamination process. The plant manager described his job as being a material converter. He pointed out that his operation is profitable when just the right amount of materials are placed in each product without waste. If material is wasted, it either comes out of the product (harming quality) or out of the company s profit because more material has to be used to replace the waste. Regardless, the company suffers a loss from either reduced product quality or reduced profitability. An additional loss also occurs from the increased costs of dealing with waste management. The Change Process I The sources and uses analysis provides a way to estimate the identity and magnitude of waste steams which reduces quality or profits. This establishes the current status of the business which can then be compared to appropriate benchmarks. The desired benchmark or standard of performance is no waste. However, some other intermediate standard maybe chosen to establish a goal for improvement. Once a goal is established, the company can move ahead in the change process. The process can be broken down into just a few steps. 1. Diagnosis Establishing present status Comparing present status to benchmarks Goal setting 2. Prescription Establishing a strategy to achieve the goal Developing a plan to implement the strategy 3. Action Execution of the plan Evaluation of results Adjustment and then returning to the first step The diagnostic step is key to the success of the entire change process. Knowing where your company stands relative to industry and regulatory standards puts you in position to evaluate the amount of change needed. In most situations change is readily accomplished if there is a good understanding of what needs to be done. In the next chapter you will find a description of the rules and regulations that influence many of the standards of performance for composites industry. When Chapter II Page 18

29 comparing your current level of performance against these standards you will undoubtedly find some deficiencies. The remaining chapters describe various methods and technologies that hopefully will help you to identify good manufacturing practices to resolve some of these deficiencies. Chapter II Page 19

30 Chapter II Page 20

31 CHAPTERIII Strategies for Working with Hazardous and Toxic Materials Introduction Developing strategies for working with hazardous and toxic materials raise a number of issues for composite manufacturers. First, to form an effective strategy you must understand the terms and laws covering the materials it is using. Therefore, this chapter will first examine some of the terminology commonly used in the regulations and then describe the regulations which typically govern hazardous and toxic materials and their disposal. Next, the elements of an employee training program for dealing with hazardous and toxic materials will be listed. The factors detailing a safety and health program are also included. Finally, the regulatory requirements for informing your employees and the community about hazardous and toxic wastes are listed. Definition of Terms According to 40 CFR 261 Subpart A, a hazardous waste is defined as any solid waste that exhibits any of the characteristics of a hazardous waste or is a listed waste. These waste materials are considered dangerous to human life and health or to the environment. Some common types of hazardous waste are: Flammables, Corrosives, Chlorinated Solvents. There are two ways of identifying hazardous wastes. One method is by checking to see if a material is a listed waste. A listed waste is any material that is classified as hazardous by the EPA or by a state or local code. These lists can be found in the document, EPA Notification of Hazardous Waste Activity. If a material you use is included on any of these lists, then it must be considered a hazardous waste (Traverse, 1991). Based on 40 CFR 261 Subpart C, Characteristic wastes are those materials which are not included in any of the EPA lists but may meet one of the following criteria: --4 Ignitability These are solid waste materials (waste ID number DOOl) which have the following characteristics: 0 it is a liquid, other than an aqueous solution containing less than 24 percent alcohol by volume and has a flashpoint less than 60 C (140 F), as determined by a Pensky-Martens Closed Cup Tester, a Setaflash Closed Cup Tester, or equivalent test methods approved by the Administrator; Chapter III Page 21

32 it is not a liquid and is capable, under standard temperature and pressure, of causing fire through friction, absorption of moisture or spontaneous chemical changes and, when ignited, bums so vigorously and persistently that it creates a hazard; it is an ignitable compressed gas as defined by 49 CFR and as determined by the test methods described in that regulation or equivalent test methods approved by the Administrator; it is an oxidizer as defined in 49 CFR a Corrosivity These are solid waste materials (waste ID number D002) which have the following characteristics: it is aqueous and has a ph less than or equal to 2 or greater than or equal to 12.5 as determined by a ph meter using either an EPA test method or an equivalent test method approved by the Administrator; * Reactivity it is a liquid and corrodes steel (SAE 1020) at a rate greater than 6.35 mm (0.250 inch) per year at a test temperature of 55 C (130 F) as determined by the test method specified in National Association of Corrosion Engineers (NACE) Standard TM as standardized in Test Methods for the Evaluation of Solid Waste, Physical / Chemical Methods or an equivalent test approved by the Administrator. These are solid waste materials (waste ID number D003) which have the following characteristics: 0 it is normally unstable and readily undergoes violent change without detonating; 0 it reacts violently with water; 0 it forms potentially explosive mixtures with water; 0 when mixed with water, it generates toxic gases, vapors or fumes in a quantity sufficient to present a danger to human health or the environment; it is a cyanide or sulfide bearing waste which, when exposed to ph conditions between 2 and 12.5 can generate toxic gases, vapors or fumes in a quantity sufficient to present a danger to human health or the environment; it is capable of detonation or explosive reaction if it is subjected to a strong initiating source or if heated under confinement; 0 it is readily capable of detonation or explosive decomposition or reaction at standard temperature and pressure Chapter III Page 22

33 ---4 Toxicity it is a forbidden explosive as defined in 49 CFR or a Class A explosive as defined in 49 CFR or a Class B explosive as defined in 49 CFR If the extract of a representative sample of the waste stream contains any of the contaminates at levels above those indicated in Table 3-1, then it is considered toxic. As a generator you have two options for determining whether you are discharging toxic materials. First, have the waste stream tested using the Toxicity Characteristic Leaching Procedure (TCLP). Second, if none of the contaminates listed in Table 1 are used or generated by your processes, you can opt not to perform the testing. Waste ID numbers for toxicity are DO04 - D043. Regulations The Resource Conservation and Recovery Act (RCRA) This act was passed in It was the first major piece of legislation that covered hazardous waste activities. RCRA controls the generation, transportation, storage, management, and disposal of hazardous wastes. It established cradle to grave liability for the hazardous waste generator. This means that the generator must know where the waste is being transported, as well as how and where it will be disposed (Traverse, 1991). RCRA divides waste generators into three categories: 0 Conditionally exempt Generators producing less than 220 lbs./month of hazardous waste Small quantity generators Producing between 220 and 2200 lbs./ month of hazardous waste Producing no more than 2.2 lbs./ month of acutely hazardous waste ( l? list) Producing less than 220 lbs. of waste resulting from cleanup of spills and residues of acutely hazardous waste 0 Large quantity generators Producing over 2200 lbs./ month of hazardous waste Producing over 2.2 lbs./ month of acutely hazardous waste RCRA specifies a number of requirements that need to be met for each level of generation. Prior to storing, treating, disposing of, or transporting hazardous waste, small and large quantity generators must obtain an EPA identification number. EPA form , Notification of Hazardous Waste Activitv, is used to begin this process. This form specifically asks a company to name both the listed and characteristic wastes they will be generating. Once a company has received its EPA identification number, it will only need to notify EPA if there is a change in the materials generated at that site or if they no longer generate hazardous materials at that location. Even though Chapter III Page 23

34 I conditionally exempt generators are not required to have an EPA identification number, many waste transporters and treatment, storage, and disposal (TSD) facilities may require a company to have an identification number before they will handle any hazardous wastes. TABLE 3-l. Toxicity characteristic chemicals and regulatory levels. EPA Hazardous Waste Number Chemical Regulatory Level (mg/l) DO04 Arsenic 5.0 DO05 Barium DO18 Benzene 0.5 DO06 Cadmium 1.0 DO19 Carbon tetrachloride 0.5 DO20 Chlordane 0.03 DO21 Chlorobenzene DO22 Chloroform 6.0 DO07 DO23 DO24 DO25 Chromium o-cresol m-cresol p-cresol DO26 Cresol DO16 2,4-D 10.0 DO27 DO28 DO29 DO30 DO12 DO31 1,4-Dichlorobenzene l,&dichloroethane l,l-dichloroethylene 2,4-Dinitrotoluene Endrin Heptachlor (and hydroxide) DO32 Hexachlorobenzene 0.13 DO33 Hexachloro-1,3-butadiene 0.5 DO34 DO08 DO13 Hexachloroethane Lead Lindane DO09 Mercury 0.2 DO14 Methoxychlor 10.0 DO35 Methyl ethyl ketone DO36 Nitrobenzene 2.0 DO37 Pentachlorophenol DO38 Pyridine 5.0 DO10 Selenium 1.o DO11 Silver S.O DO39 Tetrachloroethylene 0.7 DO15 DO40 DO41 DO42 DO17 DO43 Toxaphene Trichloroethylene 2,4,5-Trichlorophenol 2,4,6-Trichlorophenol 2,4,5-TP (Silvex) Vinyl chloride Storage Of Waste Materials On Site -- A second regulation for generators involves the storage of waste materials on site. Under this regulation conditionally exempt companies may continually store hazardous waste on- Chapter III Page 24

35 site unless the quantity exceeds 2200 pounds. Small quantity generators are allowed to store up to 13, 200 pounds for 180 days. Large quantity generators can only hold hazardous waste for 90 days. This 90 days begins as soon as a company starts to collect the waste. Manifesting Of The Hazardous Materials -- Manifesting of the hazardous materials being transported to a TSD is another requirement for generators. As with the EPA identification number, RCRA excludes conditionally exempt companies from having to manifest their hazardous waste, but a majority of transporters still require a manifest. The manifest, (EPA form ), is a multiple part form which includes the generators name, transporter s name, and list of the materials that are being carried. Waste Minimization -- In addition to the information discussed above, the manifest also contains a statement regarding the company s efforts in waste minimization. RCRA requires large and small quantity generators to sign a statement which says that they are trying to decrease the amount of hazardous waste being produced. Large and small quantity generators must also submit an annual report detailing their waste reduction efforts. Large and small quantity generators are required to comply with training and emergency and contingency plan requirements outlined by RCRA. It is recommended that conditionally exempt generators also train their employees and develop emergency and contingency plans. These requirements will be covered in more detail in the next section. Table 3-2 shows a comparison of the RCRA requirements for each of the three levels of hazardous waste generators. National Pollution and Discharge Elimination System (NPDES) There are other laws which also govern the generation of hazardous wastes. The NPDES is a permit program that covers the discharge of hazardous and toxic wastes into the nation s water system. Companies using public sewage treatment systems must meet certain pretreatment standards in order to control the discharge of pollutants which could negatively affect or simpl) pass through that treatment system. Storm Water -- Included in NPDES are the requirements regarding the permitting of storm-water discharges ( Storm-water permits, 1993). Companies must submit an individual permit application which involves writing a narrative giving descriptions of the facility and materials management practices, mapping of the facility, certification that the outcharges do not contain non-storm discharges, and quantitative testing of a storm water discharges (p. 2). Typically, EPA forms 1 and 2F have been used for this purpose. It is required that all new facilities apply for a storm-water permit at least 180 days before storm-water discharge. In addition, each company that has submitted an individual permit must develop and implement a Storm Water Pollution Prevention Plan (SPPI ) within 12 Chapter III Page 25

36 months after receiving their permit. elements ( Outline for action, 1993): This plan must include the following Site plan, Storm water management plan, Spill prevention and response plan, Preventative maintenance and good housekeeping program, Training schedule. TABLE 3-2. Requirements for hazardous waste generators. Amount Generated Manifest ~~ Annual Report ~ ~~ Training Emergency / Contingency Plans Certification of Minimization Storage on Site EPA ID # Conditionally Exempt c 220 lbs./mo. Usually I required by 1 transporter Not required Not required but recommended Not required but recommended Not required Indefinitely, unless quantity exceeds 2200 lbs. Not required by RCRA but often required by transporter or TSD facility Small Quantity Generator lbs. / mo. c 2.2 lbs./mo. of acutely toxic Full manifest required by RCRA Large Quantity Generator > 2200 lbs. / mo. > 2.2 lbs. / mo. of acutely toxic Full manifest required by RCRA Required I Required Required Required Required 180 days* cannot accumulate more than 13,200 lbs. Required * 270 days if transportation distance is over 200 miles. Required Required Required 90 days Required Ch =Ipter III Page 26

37 The use of sanitary sewer for hazardous waste disposal covers any industrial user that discharges more than 15 kilograms per calendar year of any listed or characteristic waste or any quantity of acutely hazardous waste into public treatment works. These users must submit a notification of hazardous wastes meeting those requirements. The Federal Water Pollution Control Act The Federal Water Pollution Control Act lists pretreatment standards for waste water discharged into streams, rivers, lakes, and other water sources. These standards prevent the discharge of pollutants that create a fire or explosion hazard, cause corrosive damage, cause obstruction to water flow, have a high biological demand, or inhibit biological activity because of temperature (> 100 F) (Industrial Extension Service, College of Engineering, North Carolina State University, 1993). The Clean Air Act The Clean Air Act deals with the burning of solid waste. Section 305 of Title III details the Hazardous Air Pollutants program. This section includes details on performance standards and other requirements for all categories of solid waste incinerators. In addition, 40 CFR through 112 details the regulations regarding hazardous wastes that are either burned or processed in a boiler or industrial furnace. Burning, as defined by this regulation, is either burning for energy recovery or destruction or processing for materials recovery or as an ingredient. There are four limitations that must be met in order to bum hazardous wastes on-site. These are: The hazardous waste burned in a month must not exceed the limits in Table 3-3 that are based on the terrain-adjusted effective stack height (TESH) defined by the equation TESH=H,+H1-TR where: H, = actual physical stack height, HI = plume rise as a function of stack flow rate and stack gas exhaust temperature, TR= terrain rise within five kilometers of the stack; Hazardous waste cannot contain and cannot be derived from EPA wastes numbered F020, F021, F022, F023, F026, or F027. The F series of numbers denote generic process wastes; Generator must notify the EPA of intent to operate as a small burner of hazardous waste; Generator must keep sufficient records at the facility for at least three years concerning compliance with the requirements of 40 CFR Chapter III Page 27

38 TABLE 3-3. Terrain adjusted effective stack heights (TESH) and hazardous waste burning rates. TESH Allowable hazardous waste TESH (meters) Allowable hazardous (meters) burning rate (gal/ma.) waste burning rate (gal/ma.) 'or more 1900 The Clean Air Act Amendments are just now beginning to have an impact on the composites industry. A significant aspect of the Clean Air Act and its incorporated amendments is the Title V permit program. Title V requires each of the fifty states to implement the program. North Carolina is expected to start in Each state will establish its own fee structure, options, and filing deadlines. Specific information relating to Title V requirements for the composites industry can be obtained from the Composites Fabricators Association (CFA) with headquarters in Arlington Virginia, (703) CFA has prepared a guidebook for each state to help members comply with the provisions of the clean air act. Title V establishes a permit system for those industries that release or may release any regulated air pollutant in the following amounts: 100 tons or more a year; 10 tons or more per year of any one hazardous air pollutant or 25 tons or more per year of any combination of hazardous air pollutants; Any lesser quantity of a hazardous air pollutant, as established by EPA rule-making. In addition to the above amounts, a manufacturing source will also be required to have a permit if one or more of its emissions units are regulated under the New Source Performance Standards (NSPS) or National Emissions Standards for Hazardous Air Pollutants (NESHAP). If the source is within an ozone moderate or marginal non-attainment area, it will also need a permit if Chapter III Page 28

39 it has the potential to release 100 tons per year of VOCs or N&. Other classifications have more restrictive limits: 2 50 tons per year (seriously hazardous), 2 25 tons per year (severely hazardous), 2 10 tons per year (extremely hazardous). Another reason a source may need to obtain a permit is if it releases or has the potential to release 5 tons per year of lead or lead compounds. The permit process varies from state to state but will likely include the following elements: general facility information, 0 summary information on emissions, emission unit data, supplemental data on source control. An application fee is required for all permits based on the amount of emissions for that facility. In addition, the generator is required to submit annual reports regarding emission reduction efforts for that year. Title V also requires that an annual fee be charged based on the emission level of a facility. The Hazardous Materials Transportation Act (HMTA) This act details the requirements for hazardous wastes (Traverse, 1991). According to Department of Transportation (DOT) rules, a label must be placed on a container before shipment. These labels must be visible, placed on a background of a* highly contrasting color, and should contain the following information about the chemical: the proper shipping name, the United Nations (UN) number for the material, the name of the shipper, the name of the receiver. Although the EPA does not require this level of labeling for materials stored on site, it is often much easier to label these materials as required by the DOT than to do so while a transporter waits to take these materials off site. Employee Training In Title I of the Superfund Amendments and Reauthorization Act (SARA), OSHA was mandated to develop training requirements for workers handling hazardous waste. In response, OSHA developed standard 29 CFR or Hazardous Waste Operations and Emergency Response (Hazwoper). According to this standard, hazardous waste site workers must complete a minimum 40 hour off-site training course with at least three days of on the job training before they are allowed to handle hazardous waste. The Chapter III Page 29

40 following areas must to be covered in this training (North Carolina Department of Labor, 1993): Names of personnel and alternates responsible for site safety and health; Safety, health, and other hazards present on the site; Use of personal protective devices; Work practices by which the employee can minimize risks from hazards; Medical surveillance requirements including recognition of symptoms and signs which might indicate overexposure to hazards; Types of procedures used for decontamination; Understanding of an emergency response plan which meets the requirements for safe and effective responses to emergencies; Types of procedures used for confined space entry; Understanding of spill confinement programs. Supervisors of those employees directly involved in hazardous waste activities must also receive 40 hours of off-site training. Workers who only occasionally work on site or those who are not exposed over the permissible limits need to undergo only 24 hours of off-site training and at least one day of on the job training. Every person successfully completing this training should be issued a training certificate. Each year, following the completion of this initial training, an eight hour refresher course is required for all these employees. In addition to the training requirements of required in the safety and health program of hazardous waste: Hazwoper, the following items are of a company involved in the use Site characterization and analysis to identify hazards and make plans for worker protection; Development of site control measures to minimize the potential for employee contamination; Implementation of a medical surveillance program for all new, current, and terminated employees; Development and implementation of engineering controls to protect employees; Chapter III Page 30

41 ...T ^..-L...L^.-.,.--. -_ I Selection of appropriate personal protective equipment based on the site hazards; Implementation of a monitoring procedure for hazardous material exposures; Use of information programs to inform all employees including contractors of environmental hazards; Development of a program for the proper handling of drums and other containers to prevent injuries;. Development and implementation of decontamination procedures before anyone enters a hazardous area; Development of a written emergency response plan; Implementation of new technology programs to increase employee awareness of new equipment, processes, and procedures that may contribute to their safety and health on the job. Hazard Communication Although Hazwoper covers many of the issues of working with and around hazardous wastes, OSHA requires that all employees understand the types of hazards which are found in a facility. The Hazardous Communication (Hazcom) standard or 29 CFR (North Carolina Department of Labor, 1993) covers the requirements entailed in the workers right to know rule. The items an employer must comply within this rule include: Conducting a hazard determination of the site; Developing a written hazard communication program which includes the methods an employer will use to get the proper information regarding hazardous materials to their employees; Using labels and other forms of warning properly; Having material safety data sheets available that contain all the required information; Developing and implementing an employee training program which includes the following elements: 1. The methods and observations that may be used to detect the presence of release of a hazardous chemical in the work area; 2. The physical and health hazards of the chemicals in the work area; 3. The measures an employee can take to protect themselves form these hazards, including specific procedures the employer has implemented to protect employees from exposure to hazardous Chapter III Page 31

42 chemicals, such as appropriate work practices, emergency procedures, and personal protective equipment to be used; 4. The details of the hazardous communication program developed by the employer, including an explanation of the labeling system and the material safety data sheet, and how employees can obtain and use the appropriate hazard information; Applying for and detailing the use of trade secrets. Emergency Planning and the Community Right to Know Title III of the Superfund Amendments and Reauthorization Act (SARA) requires industries to notify the community of toxic chemicals which may be released either routinely or accidentally. Industries must submit EPA Form R, the Toxic Release Inventory (TRI) Reporting form, if they are classified under the Standard Industrial Classification (SIC) codes and manufacture, process, or otherwise use any listed chemical or chemical category in the quantities prescribed by the EPA. Industries that manufacture and process any listed chemical must use over 25,000 pounds in a calendar year before they are required to file. Companies that do not manufacture of process but use any listed chemical must file if they use 10,000 pounds or more in a year. Companies that do not fall into any of these categories do not need to file (Environmental Protection Agency, 1993). Conclusion There are many issues surrounding the generation of hazardous and/ or toxic wastes. They range from initial identification through off-site transportation and final disposal. The legislation covering these different areas, as well as training requirements, are complicated and often confusing. It is hoped that the information in this chapter will assist you in dealing with the wastes found at your facility. Chapter III Page 32

43 : References Environmental Protection Agency. (1993). Toxic chemical release inventorv reoortine Form R and instructions (EPA Publication No. 745-K ). Washington, DC: U.S. Government Printing Office. Industrial Extension Service, College of Engineering, North Carolina State University. (1993, September 1). Hazardous waste management for small ouantitv generators. (available from the Industrial Extensive Service, College of Engineering, North Carolina State University, Box 7902, Raleigh, NC ). North Carolina Department of Labor. (1993). North Carolina occunational safetv and health standards. Chicago: Commerce Clearing House, Inc. Outline for action: Storm-water pollution prevention plans. (1993, Summer). Focus: Waste Minimization, 2,4. Storm-water permits: Applications options. (1993, Summer). Focus: Waste Minimization, 2,2. Traverse, L. H. (1991). The generator s guide to hazardous materials/waste management. New York: Van Nostrand Reinhold. Chapter III Page 33

44 Chapter III Page 34

45 Introduction /CHAPTER IV. Production-Based < Pollution Reduction Strategies Before your company formulates a strategy for pollution and waste reduction, you have some choices to make. There are two approaches to the task of pollution and waste reduction. One is containment and compliance, and the other is waste reduction and compliance. The first approach focuses on filtering, trapping, or treating pollution and waste streams. This approach means people spraying resin will wear respirators, install expensive ventilation/ make-up air systems, and properly drum and dispose of toxic and hazardous waste. The second strategy relies heavily on engineering and technology to avoid, remove, or reduce waste streams from the manufacturing system. The engineered approach can also be cost effective. The opportunities available for companies to reduce or avoid waste and pollution streams are dictated by the product type, volume, and the resources a company has available. Consequently, a company must evaluate the appropriateness of the technologies available to create a strategy that they can develop and implement. These opportunities can be found in four major areas: Product Design, Materials, Manufacturing Technology & Methods, Work-force Ability. The strategy developed will undoubtedly involve changes in more than one area. A profitable strategy will probably require a company to make changes in all four areas. Nevertheless, it s unlikely that a company s strategy to con+ will be purely containment or avoidance. It will probably be a blend of both approaches with one setting the theme for the resulting strategy. Consequently, this chapter focuses on various manufacturing technologies and methods for applying resins to create laminates. Although materials are included in the chapter, this part of the discussion focuses on resins since they are probably the most significant materials in terms of impact on waste and pollution streams. The selection of a resin type and application technologies are the foundation of a waste and pollution reduction strategy. The methods for applying resin can be classified into two major categories: guns, 1. Spraying wet-out methods, 2. Liquid wet-out methods. The first category, spraying wet-out methods, includes four types of spray The methods for liquid wet-out are more diverse and include several groups of technologies. Examples from these groups include flow coaters, resin rollers, infusion systems, and resin transfer molding (RTM). Chapter IV Page 35

46 I _-- -_-- Ad-.-._ _ -., I Resin Application Technologies Relative Cost Comparisons. Spray Coat Spraying Wet-Out High Atomkatlon II El Tooling Cost Equipment Cost 1 Waste and Scrap Cost cf Workplace and Environmental Control Cost Liquid Wet-Out No Atomization *With Reusable Bagging FIGURE 4-1. Comparison of costs for resin application technologies. When evaluating the suitability of these methods, a manufacturer should consider four categories of cost as they apply to each method. These costs are: Tooling cost -- The cost to provide a mold suitable for the resin application technology. RTM has a high tooling cost because it requires both a female and male mold. Several of the other methods require only one mold. Chapter IV Page 36

47 I ;r I.-- A pyy_-- Equipment cost -- The cost of the resin application equipment and the necessary support equipment. As an example the resin roller is a relatively inexpensive applicator, however, to use it productively requires an overhead trolley to support the hoses and static mixer to give the operator complete freedom of movement in the work area. Waste and scrap cost -- Each method of application has an inherent system of waste. For example, conventional spray equipment creates overspray and a significant amount of styrene loss to the atmosphere. Workplace and environmental cost -- Dealing with waste and scrap generated by each technology creates a second set of costs. Consider conventional spray as an example. To use this inexpensive resin application equipment, a fabricator must also pay the costs for ventilation equipment, protective clothing and respirators, make-up air, and overspray clean-up. Figure 4-l shows the relationship of these costs for each of these technologies. The relative cost comparisons between technologies also indicates some of the potential for improvement in waste reduction. However, factors such as part design and volume must also be considered before including one of these methods in a waste reduction strategy. These factors and others are included in the discussion on each of these methods of application in the next sections of this chapter. Wet-Out Methods Using Spray This section describes four types of spray systems used to apply gel coat and resin to the laminate. Of the two materials, gel coat is by far the most critical in terms of selecting a spray method because the gel coat must be applied in a dense uniform film thickness to provide protection to the laminate from environmental stress and furnish the necessary appearance characteristics demanded by the customer. Resin application, however, is far less demanding since most laminators will use rollers, brushes, or pressure to redistribute excess resin in the laminate. Consequently, most of the comments on the following spray systems reflect the critical application requirements demanded by gel coating. Conventional spray guns The use of conventional spray guns to apply resin and gel coat to open molds is one of the most popular methods in use by fabricators of fiberglass products. Conventional spray application systems pump the gel coat through a fluid nozzle. Once the resin exits the nozzle, it is caught in the turbulence created by air streams exiting the air cap. The atomizing air pressure is typically around 60 psi. Most conventional guns spray the catalyst into this steam so that it can be mixed by the turbulence created by the air cap. This type of gun is called an external mix spray gun. These systems have been in use for many years. Chapter IV Page 37

48 1..r-...v-.._ -_ f : FIGURE 4-2. Air Atomization nozzle. The atomization nozzle for a conventional spray gun is shown in Figure 4-2. These systems offer good control over spray patterns but are not well suited for efficient delivery of thick resins such as the newer low styrene resins (~35% styrene). Airless Spray Guns These guns are designed so that resins are atomized by being pumped at extremely high fluid pressure through an atomizing nozzle. Airless spray guns are considered to be more efficient in delivering resins to the work surface. Large quantities of gel coat and other resins can be rapidly transferred with these systems. For efficient atomization and delivery, pressures in the range of psi may be required. These high pressures, while necessary for atomization and spray pattern development, contribute to excessive fogging, overspray, and bounce-back during the spray-up process. Recent developments in spray gun design have resulted in new systems which blend positive characteristics of both air and airless spray guns into one unit. Air Assisted Airless Guns Like airless guns, these units use fluid pressure to atomize resins through a spray nozzle. However the fluid pressure utilized is considerably lower ( psi) than airless guns and therefore must be augmented by introducing pressurized air into the resin spray pattern as it exits the pressure nozzle. An example of the nozzle system is pictured in Figure 4-3. Unlike conventional air spray guns, air assisted airless systems require a very low compressed air pressure at the nozzle (3-30 psi). This low air pressure produces an envelope which picks up material dispensed from the pressure nozzle tip. The envelope can be regulated to assist in developing a refined controllable spray pattern. Chapter IV Page 38

49 sp =Y nozzle FIGURE 4-3. Air assisted airless spray nozzle. Potential Benefits of Air Assisted Airless Spray Guns -- Air assisted airless spray guns for resin application can not match the high volumes of material transfer attainable with airless systems or conventional spray guns. However, the reduction in material losses due to excessive fogging, overspray, turbulence, and bounce-back are significant. The gentle air and pressure atomization allows for the development of spray patterns that offer a high degree of control while greatly reducing the velocity of particles. Lower pressures may help reduce material waste, maintenance of pressure lines and fittings, and wear on pumps. Reduced delivery pressures can help in providing a cleaner, safer, and more comfortable work area. External emissions and the need for high levels of makeup air may also be reduced. Economic Factors -- For gel coating the air assisted airless method does not provide high material delivery rates and good atomization like airless spray systems. The lower pressure can result in a coarse orange peel when spraying gel coat. This can result in a higher than desired variability in the mil thickness of the gel coat. When spraying lower viscosity resins these problems are not apparent. Installation of air assisted airless spray systems does not require extensive modification of the physical facility or the production techniques already in place. Spray guns can frequently be adapted to make use of existing pressure pump and control svstems. High capacity air compressors are not required. Attention to nozzle cleaning is essential. Other maintenance and repair procedures differ little from the requirements of other systems. Units are available from a number of suppliers (see Appendix C). Initial expense may be returned quickly in many applications when converting from conventional spray equipment. More of the product will get to and remain on the working area rather than mixing with plant or exhaust air or coming to rest on the floor, walls, and other nearby surfaces. Chapter I\ Page 39

50 c,l&-ea wa-11* _..--_--.---A--.., 1 High Volume Low Pressure (HVLP) Spray This is the most recent development of the four types of spray equipment commonly in use in the composites industry. HVLP is often compared with conventional air spray guns since both use compressed air for atomization. However, HVLP is limited to 10 psi, while conventional air spray is frequently operated at pressures of 60 psi or greater. The higher pressure used by conventional guns creates the fogging, bounce-back and overspray that characterize air atomized spray. All of this results in transfer efficiencies for conventional spray guns of less than 40%. HVLP spray guns, however, can attain transfer efficiencies of 65% or more (according to one manufacturer). To accomplish this transfer efficiency HVLP guns require a high volume of air (10-20 CFM) delivered at a pressure of approximately 10 psi to atomize the material. Material pressure (hydraulic pressure) coming to the gun falls between 200 to 2000 psi. Once the gel coat leaves the orifice, the low pressure air completes the atomization and encapsulates the resin fan on its way to the mold surface. This creates a soft low velocity spray which accounts for the high transfer efficiency of, this method. Potential Benefits -- HVLP spray guns have been evaluated by Hatteras Yachts in High Point, North Carolina. In this evaluation Hatteras sprayed small parts as well as large parts (such as hulls and superstructures). The operators reported that the spray from the gun was soft and provided a more uniform coat than they obtain from their airless spray equipment. They reported that the gel coat flowed more evenly and the surface finish was flatter and smoother. Operators compared the finish to a painted surface. The operators also commented that they got far less gel coat on them and the odor of styrene and catalysts was reduced. Economics -- Hatteras Yachts ran a comparison test between airless spray equipment and HVLP equipment. In these tests they measured the overspray in pounds of gel coat for two sizes of boats. The overspray from airless equipment is shown in the Table 4-l. TABLE 4-1. Overspray from airless spray equipment. Component Gel Amount of Overspray in Coated Pounds 39 Hull 11.7 Superstructure Hull 16.2 Sunerstructure 29.7 Overspray in Pounds Per Foot The HVLP spray equipment (based on the operators estimates) reduced the overspray by 25%. This means that on a 54 hull and superstructure there was a reduction of 11.5 pounds of gel coat overspray. Hatteras estimates that HVLP Chapter IV Page 40

51 spray equipment in their application would provide an annualized material savings in gel coat of just over $900. Case Study No 1 Type: Company: Location: Contact: Phone: Purpose: Motivation: Equipment: Supplier: Payback Period: Comments: Source: High Volume Low Pressure (I-IVLP) spray guns Hatteras Yachts High Point, NC Robert C. Arthur, Engineering (910)~ Reduce overspray of gel coat Reduce Material Usage Reduce clean-up requirements Improve gel coat quality Reduce waste Improve product quality Binks HVLP spray gun Binks Manufacturing Company 9201 Belmont Ave. Franklin Park, IL Not available Reduction of waste from overspray compared to airless spray equipment was estimated at 25%. North Carolina Pollution Prevention Challenge Grant Report submitted 6 / 16/ 94 by Hatteras Yachts. combining Reinforcement With Resin Spraying, Spray Lay-Up The spraying systems described so far can apply gel coat to a mold * or resin to wetout dry fiberglass. Spraying resin and placing fiberglass in dry sheets m a mold is a common practice termed hand lay-up. However, using spray lay-up, (chopper guns) is an equally common practice for building a laminate. This method combines spraying and reinforcement material application into one system. The system consists of a gun-type resin applicator combined with a feeder which propels chopped roving into the fan of atomized resin. The gun uses compressed air to atomize the resin, create turbulence to mix the catalyst, and propel the chopped fiber to the mold surface. (see Figure 4-4). Chapter IV Page 4 1

52 glass chopper s-t lay-up of resin and reinforcment FIGURE 4-4. Fiberglass spray lay-up. This combined form of resin and material application can build up a laminate very quickly. However, the extremely high atomization and delivery pressures in older chopper guns caused high levels of styrene emissions and waste due to overspray. NOW HVLP spray guns are being adapted to work with a glass fiber cutter assembly to create a HVLP chopper gun. Although this means of building a laminate is inherently messier than hand-lay-up, the use of HVLP spray can reduce overspray and styrene loss through atomization. Manufacturers of spray equipment can provide additional information on the features and characteristics of this equipment. Appendix C lists these suppliers. Prepreg Fiber Reinforcing Liquid Wet-Out Methods For a number of years fabricators of composite aircraft structures have relied on the use of fiber reinforcements that are presaturated with resins. These materials, referred to as prepregs, offer a number of advantages over conventional spray techniques. Resin to fiber ratios can be closely controlled; atomization of pollutants is practically eliminated; and clean-up and disposal problems are greatly reduced. These advantages are, however, not enough to make prepregs widely accepted by most fiberglass fabricators. Prepregs are generally formulated with more expensive epoxy based resins which require placing the mold in an oven or autoclave to complete the cure cycle. These more expensive resins are normally combined with exotic, high strength reinforcing materials, such as graphite fibers. Storage is also a problem since the materials must remain refrigerated until the lay-up process is begun. Prepregs Chapter IV Page 42

53 appear to be best suited for applications where extremely high strength-to-weight ratios are required and cost factors are secondary. In-House Resin Impregnation Equipment is now available to provide the fabricator with some of the advantages offered by epoxy prepregs while using lower cost polyester resins and fiberglass materials. Impregnators can be placed within the lamination area of a plant and mounted in such a manner as to feed resin saturated reinforcing materials directly to the molding operation. A static mixer can be incorporated with conventional resin pumps and a catalyst metering device to provide the proper mix to a roller-reservoir system. Woven fiberglass is impregnated as it passes through this reservoir system. A schematic of the system is pictured in Figure 4-5. Impregnators can be designed to fit a variety of potential applications. The units can be mounted for convenience to lift systems, over conveyor fed lines, on bridge cranes, or on portable carts. Conventional resins and roll fiber materials are used. Machine size and capacity can be engineered to provide a variety of output feed rates and to accommodate a number of roll widths. Units currently available can produce as much as 20 linear feet per minute with resin-to-glass ratios controllable to within ~2%. Larger units have an output capacity which can exceed 1,000 pounds of laminate per hour with a 50% glass content. Potential Benefits -- Impregnators would appear to have considerable potential for the reduction of pollution associated with open molding operations. Delivery of the resin to the reinforcing laminate by means of an impregnator would help insure that a cleaner, safer, and more comfortable work area would be maintained. Since there would be no spray atomization of resins, the levels of in-plant and external emissions would be minimized. At the same time, requirements for high levels of make-up air and elaborate air handling systems would be minimized. Application potential for impregnators appears to be highest for users of roll type materials who are either large volume producers or fabricators of large components. Facilities whose molds are widely scattered throughout the plant and are used to produce only one product per day will have difficulty in providing expensive units for a variety of areas or in moving units to a number of locations. Fabricators who can consolidate production lay-up facilities can use a single machine to feed operations on a number of smaller molds, while fabricators of large components can use a single machine to rapidly deliver large quantities of materials. Quality and productivity may be improved through the use of resin impregnation systems. High volume delivery rates can speed lay-up of large components and lead to the development of an assembly line approach to molding smaller components. Impregnators insure a high degree of control of fiber-to-resin ratios and catalyst-to-resin ratios. Worker productivity may also be -~ Chapter IV Page 43

54 expected to improve because strenuous rolling operations are reduced and air within the working environment will be less contaminated from styrene. reinforcing fiber roll stock FIGURE 4-5. Impregnator system for fiberglass. Economic Factors -- For many fabricators, installation of impregnator systems may require extensive modification in the plant layout and production techniques. The units are more expensive than existing spray applicators, but their per unit output can be considerably higher. Use of impregnators by builders of small boats would appear to be economically feasible only if the facility could be arranged so that the molds are handled in an assembly line manner, or situated so that one machine could be easily positioned to feed a number of molds. Impregnators merit attention from any company planning new facilities or major changes to existing facilities. Builders of larger components, such as large boat hulls or tanks, may be able to use impregnators with little change in plant facilities. Maintenance and repair requirements would appear to differ little from the requirements of conventional spray systems. Units are available from suppliers identified in Appendix C. The potential for savings is greatest where operations demand the production of large volumes of resin saturated roll stock. Small volume producers are not Chapter IV Page 44

55 likely to find great use for currently available systems. Payback potential lies in five areas: 1. Increased output of saturated laminates, 2. More efficient use of materials, 3. Improvement of existing processing strategies, 4. Improvement of laminate quality, 5. Reduction of the need for elaborate air filtration and other pollution control sys terns. Units in Use -- Impregnators are in use at Bell Halter Marine in New Orleans, Renaissance Creations in Atlanta, and Syntechnics Inc. in Paducah, Kentucky. Typical applications include the construction of hulls of Navy mine sweepers, production of barge covers, and fabrication of large architectural panels. Most impregnator units are used in the production of large components, including some structures with weights of several tons each. Type: Company: Location: Contact: Venus Impregnator Syntechnics Inc. 700 Terrace Lane Paducah, KY Case Study No 2 Teddy Hold, Plant Manager Phone: Purpose: Motivation: Equipment Supplier: Payback Period: Reduce spray-up requirements Reduce plant clean-up requirements Reduce material consumption Improve production of large components Maintenance of air quality Production improvement Venus-Gusmer, Inc Ives Ave Kent, WA Not available Chapter IV Page 45

56 Case Study No 2 Continued Comments: Source: Three units are used in the production of large barge and tank covers. In November, 1994 the plant manager, Mr. Hold indicated that the impregnators continue to provide the service and performance expected of them in Phone conversations with plant manager (May, 1987 and November, 1994) and with the equipment supplier (December, 1986 and March, 1987). Resin Rollers -- Spray-less Application Systems Roller dispensing of resin is receiving a considerable amount of attention as a possible method for reducing styrene emissions without requiring major modifications in molds and materials. Like spraying systems, resin roller, dispenser units utilize a fluid pumping system to draw resins from drums or bulk distribution lines. This pumping system also includes a separate, fully adjustable catalyst pump. These two pumps supply the resin and catalyst to a static mixer. Since atomization is not required, resin delivery pressures are well below 100 psi. Pressures are normally regulated for the purpose of controlling the rate of resin delivery. Catalyst flow rates are precisely tied to resin flow to insure a high level of control over catalyst-to-resin ratios and cure rates. Delivery rates for catalyzed resins may be as high as 20 pounds per minute. A flexible material hose is attached to the mixer and carries the catalyzed resin to the roller applicator. Units can be mounted to wall fixtures or portable carts. However, a more effective method is to mount the static mixing unit on an overhead traveler that looks like a lightweight gantry crane. This arrangement gives the operator complete X-Y freedom of movement without having to hold or drag a hose around the work area. This set-up also reduces the volume of catalyzed resin and reduces the chance of resin gelling in the wand and roller. The roller handles are normally adjustable in length to allow for a variety of working requirements. As the operator rolls out the reinforcing materials, he or she can control the flow of resin as needed through a trigger mechanism. The resin flow is distributed by a manifold within the roller. A typical roller cover is about 9 wide by 1 l/2 in diameter and has about 150 holes that are about l/32 in diameter. This arrangement distributes the resin uniformly around the circumference of the roller. In operation the roller is in continuous use throughout the shift so the catalyzed resin is always being flushed through the roller cover until it is discarded at the conclusion of the shift. After the roller cover is discarded, the mixing unit, hose assembly, wand, and roller manifold are flushed using a small amount of solvent recirculated in a closed system. Another advantage inherent in the roller system is the combining of tasks -- the operator does not need to change tools as often when switching from resin Chapter IV Page 46

57 r, h application to roll out operations. Figure 4-6. An example of a roller system is pictured in Potential Benefits -- Resin roller dispensers can transfer catalyzed resins to the molding surface totally eliminating material losses due to spray vaporization, fogging, overspray, turbulence, and bounce-back. External emissions and the need for high levels of make-up air can be reduced. A reduction in unneeded air movement within the plant can further reduce styrene emissions. The low delivery pressures required also help to reduce maintenance while providing a cleaner, safer, and more comfortable work area. Installation of resin roller dispenser systems does not require major modifications of the production facility or the tooling already in place. High capacity air compressors are not required. These units are beneficial in facilities that are not equipped to exhaust and make-up large quantities of air in the working environment. Since overspray is eliminated the need for protective clothing other than gloves is not required with this type of equipment. Other than replacing roller covers, routine maintenance and repair will be less than the requirements of conventional spray systems. Although the amount of resin being dispensed per minute is less than spray guns, the actual pounds of laminate produced per hour of labor is very competitive with other forms of hand lay-up methods. The issue of productivity is addressed in a case study on waste reduction and profitability found in Appendix A. In the study this method of resin application was used as part of an overall approach to significantl! reduce costs as well as waste. Units of this type are frequently used in Sweden and Norway because of highly demanding emission regulations. If your application involves hand lay-up then you should consider method of resin application. A list of suppliers of roller dispenser units are listed in Appendix C. Economic Factors -- Resin rollers are available through most companies that manufacture spray equipment. In general a laminator can eliminate virtually all overspray when switching from spray to roller distribution of resin. Manufacturers of the equipment claim that a resin roller will save a laminator, 1-10% in resin usage. Hatteras Yachts in their study comparing resin rollers to external mix spray equipment, found that overspray was completely eliminated resulting in a pound savings in resin on a 54 hull and superstructure. The annualized savings generated by one roller would amount to $10,178. However, the study noted that productivity was adversely affected and reduced the savings realized. Other laminators have noted that the switch to resin rollers requires some additional investment in work area design and handling equipment to ru orth Carolina Pollution Prevention Challenge Grant report, Evaluation of Direct Resin Atwlicator and HVLP Gel Coat EcluiDment in Large Fibewlass Boat Construction, Robert C. Arthur, Hatteras Yachts, 6/ 16/94. Chapter IV Page 47

58 Resin Feed Hose Handles / Roller Frame Rez;in Tube Roller Cover \ Roller Cover Core Drilled For Resin Distribution I FIGURE 4-6. Resin roller and wand. Chapter IV Page 48

59 _ _ support the static mixer and supply lines. Changing work methods so that resin application is being done continuously using a smaller laminating crew is also necessary to achieve the needed productivity and to retain all the material savings. AppIications -- Arjay Technologies in Largo, Florida, has used resin rolling in the manufacture of yachts for many years. In North Carolina several companies are actively studying the application of resin rolling and the changes needed to introduce the method successfully into their laminating operation. Grady-White in Greenville, North Carolina has one unit and is planning to put it into service during Hatteras Yachts in High Point North Carolina has tested resin rollers and has reported on its use in large yacht construction. The units are widely available, and most manufacturers of resin dispensing equipment can provide performance and application information for most open mold products (See Appendix C). Case Study No 3 Type: Company: Location: Contact: Phone: Purpose: Motivation: Equipment Supplier: Payback Period: Resin Roller Arjay Technologies 2020 Wild Acres Road Largo, FL Robert L. Cottrell, President (813) Reduce overspray of resins and clean-up requirements Reduce styrene emissions Improvement of air quality Improvement of product quality Binks Manufacturing Company 9201 Belmont Ave. Franklin Park, IL Not available Chapter IV Page 49

60 Case Study No 3 Continued Comments: Source: Remarkably clean work area in the laminating room. Noticeable reduction of overspray. Styrene odor was very slight while one team was working on laying up a deck for a large sailboat. Plant visit in August, 1994 and phone conversations in September, 1994 Case Study No 4 Type: Company: Location: Contact: Phone: Purpose: Motivation: Comparison of Styrene Emissions Resin Spray vs. Resin Roller Grady-White Boats, Inc. Greenville Blvd. NE Greenville, NC Doug Hoffman, Plant Engineering Manager (919) Reduce styrene emissions Improvement of air quality Reduce waste Equipment Supplier: Test Conditions: Resin Roller Binks Manufacturing Company 9201 Belmont Ave. Franklin Park, IL Styrene levels are from the lay-up of a 17 hull in a 34 x 58 bay enclosed on three sides in a larger resin laminating building. Temperature was degrees with a relative humidity of 40-45%. The polyester resin was non-surpressed with a % styrene content.. Styrene Levels, Time Weighted Average Test Location Resin Spray Gun Resin Roller from the hull 28.5 PPM 15.0 PPM Comments: Measurements were taken using low flow pumps calibrated betweer cc / minute using charcoal sorbent detector tubes. Testing conducted during November and December, Chapter IV Page 50

61 Vacuum Bag Molding The basic methods used in open molding fabrication have changed little during the past 30 years. Open molding spray-up and hand lay-up production techniques offer a number of advantages for firms that require a limited number of units from each mold, need a rapid start up, and have limited capital for tooling. Open molding unit costs are high due to the labor intensive methods and limited daily output. Because of limited production requirements and / or unique product designs, many fabricators will continue to rely on open mold fabrication. However, efforts to improve open molding processing techniques appear to have gamed momentum during recent years. Some of the advantages of closed molding technologies, notably higher glass to resin ratios and reduced waste and emissions, are being sought. Firms engaged in the manufacture of high performance composites, such as aircraft components, have been forced to develop many new approaches to open molding. Use of specialized materials such as carbon fiber reinforced epoxy prepregs, exotic core materials, and unique reinforcing fiber combinations has led to the development of innovative tooling, lay-up strategies, and curing approaches. While most fabricators will have little use for the autoclaves required to work with exotic high strength material, other processing strategies, such as vacuum bagging, appear to have potential for bringing some of the advantages of closed molding to open molding. Vacuum Bag Molding Processes Vacuum bag molding processes can be set up to replace many conventional open molding operations. Molds are built from the same materials using the same techniques required for creating open molds. Resins and filler materials differ little from those used to produce components in open molding. Conventional gel coating operations can also be utilized. The vacuum bagging process begins with the application of a gel coat to the surface of the mold. When a high quality finish is desired, a surfacing layer of glass is carefully placed over the gel coat. Glass reinforcing and other materials, such as core stock, are cut to fit and placed in the mold. Catalyzed resin can be sprayed, pumped, or poured over the lay-up. Where multiple layers of reinforcing and/or core materials are used, the resin should be applied so that proper distribution to all parts of the lay-up can be assured. Once the lay-up materials are in place, the exposed area is covered by special layers of plastics which are sealed to the edges of the mold. Before the resin begins to cure, a vacuum is drawn through one or more strategically located ports in the mold or the plastic cover. A cross section of a vacuum bag molding set-up is pictured in Figure 4-7. A number of benefits can be derived through the use of vacuum bag lay-up. With the exception of the gel coat, resin delivery can be accomplished without atomization. Labor involved in rolling out air bubbles and distributing the resin is reduced since the vacuum can be used to insure full distribution of resin to all Chapter IV Page 5 1

62 parts of the lay-up. A high degree of control of resin-to-glass ratios can be maintained by carefully controlling the vacuum and by placing a release film (peel ply) and bleeder material between the laminate and the vacuum bag to absorb excess resin. Complicated lay-ups with reinforcing core stock can be accomplished in one operation instead of in steps that require curing before new layers are added. Product quality and strength are improved since the vacuum removes trapped air and serves as a clamp to insure tight bonding of all materials in the lay-up. The release film, or ply, applied over the lay-up can be smooth or textured to Produce a rough, smooth, or patterned surface. Vacuum Bag Lay-Up Step 1 Reinforcement materials placed in mold by hand. Resin applied by spray or flow coater. Fiber Reinforcement & Resin Core W Mold Vacuum Bag: Lav-Up Step 2 Apply release ply, bleeder, and vacuum bag to cover wet lay-up. Controlled vacuum applied to eliminate voids and excess resin. Release Vacuum Film Bag Fiber Reinforcement & Resin I Bleeder I To Vacuum PlY Sealant Core Tape I I I I I I Mold FIGURE 4-7. Diagram of a vacuum bag molding set-up. Chapter IV Page 52

63 Since vacuum requirements are typically low and curing takes place at ambient temperatures, molds can be made of conventional tooling resins and reinforcements. Molds are laid-up over a pattern in the same manner as those used for open molding. Some specialized tooling may be required in the form of vacuum lines, fittings, and ports. A substantial vacuum pump and manifold system are also required. Potential Benefits -- When spray guns are not used to deliver resin to the mold, styrene emissions can be greatly reduced. Since final distribution of the resin to all areas of the lay-up is largely controlled by the vacuum, gel coating is the only step in vacuum bag molding that requires atomization of resin. Pumping or pouring premixed catalyst and resin into a closed mold eliminates fogging, bounce-back, and overspray. Vapor emissions and odor are further reduced by confining the resins in the covered mold until curing is complete. Excess resin can be trapped by,bleeder material placed under the vacuum bag. Even dust producing secondary grinding operations are reduced because the closed molding system eliminates most flash removal and edge smoothing requirements. Quality and productivity may be improved through the use of vacuum bag molding. The molding system produces parts with smooth surfaces and internal structures which are free of voids and excess resin. Open molding may require two or more operations to produce parts with high performance core stock, while vacuum bagging allows the lay-up to be accomplished in one operation. Start up and tooling can be accomplished quickly and economically. Direct lay-up labor costs may be reduced, and rate of production from a mold may be improved. Resins used in some vacuum bagging operations may have to be designed for the process. With large or complex structures, gel times will need to be extended, and thick lay-ups should use resin systems that will not produce excessive heat. When the application of material can be accomplished within a relatively short period of time, conventional resins may be used. Economic Factors -- Vacuum bag molding is probably best suited for intermediate volume production of small to midsize components. Items such as large boat hulls and aircraft wing structures have been produced using vacuum bagging techniques, but large surface areas may be difficult to cover with lay-up materials before resins begin to gel. Products such as seats, boat hatches, boat deck structures, cored bulkheads, and other items with relatively shallow draft molds are ideal for this type of processing. The release film can also impart a fair finish on the second surface that may eliminate a need for secondary operations to improve the inside finish. Initial investments in vacuum bagging may be returned quickly in some applications. In comparison to open molding, potential payback is greatest where production rates are moderate, high strength and low weight are essential, and the shape of the product is not overly complex. Payback potential is limited when the mold design features deep drafts or complex shapes and demands of quality and strength are only average. A cost that must be considered is the extra solid waste that this method generates. Although some molders are able to reuse Chapter IV Page 53

64 the fittings and even the bagging material, the bleeder material and the release film are all waste. The amount of cured resin that is thrown away in the bleeder material can be minimized by careful application of just the right amount of resin to the laminate. If this is not controlled, vacuum bagging can be an expensive source of solid waste. Since most fiberglass processors have limited financing for research and development of new production processes, vacuum bagging with good resin control is an attractive production alternative. Suppliers of vacuum bagging materials are listed in Appendix C. Applications - Vacuum bag molding has been successfully used by Hatteras Yachts in New Bern, North Carolina, and by Fountain Powerboats in Washington, North Carolina. Hatteras uses the process in the production of a number of small parts and for production of floor units and bulkheads for larger yachts. The process is used almost exclusively with high strength-to-weight ratio components which are cored with high performance structural foam. The units produced exhibited outstanding structural integrity and good surface quality. Floor and deck systems produced by Hatteras are essentially large flat shapes that sandwich several inches of core stock between outer skins of fiberglass reinforced polyester. Many of these units are well over 250 sq. ft. in area. Lay-up of the units is accomplished in one operation, with resin applied both above and below the core stock. Once all materials are in place, they are covered by a release film, a bleeder material, and a vacuum bag which is sealed to the edges of the mold. No gel coat is used on the floor systems since they are covered by finishing materials after installation. For most small parts, molds are gel coated before lay-up is started. Fountain Powerboats has used vacuum bagging to produce a number of small parts including engine compartment hatch covers. Currently they use the technique only for boats produced for the military. Case Study No. 5 Type: Company: Location: Contact: Vacuum Bag Molding Powerboat Engine Compartment Hatches Fountain Powerboats P. 0. Drawer 457 Washington, NC Mike Good, Design Engineering Phone: (919) , Purpose: Improve product performance Reduce number of operations Chapter IV Page 54

65 Case Study No. 5 Continued Motivation: Equipment Supplier: Payback Period: Comments: Source:. Quality improvement Increased production Rimcraft Technologies Not available In 1987 vacuum bag molding was thought to be beneficial for one step lay-up of the high performance materials being used. In follow-up conversations seven years later, vacuum bagging is seldom used due to the large amount of solid waste generated from the peel ply and bleeder material. Builder indicated that use of vacuum bagging applications would be increased if this waste factor could be substantially reduced. Plant visit (May, 1987) and phone conversations (October, 1994). hfusion Infusion shares many of the characteristics of vacuum bag molding and resin transfer molding (RTM). Like RTM, infusion reduces styrene emissions by wetting out and curing the laminate in a closed system. The use of air pressure to squeeze the resin into the reinforcement fibers is a benefit that infusion has in common with the vacuum bagging process. One form of the infusion process, known as the SCRIMP (an acronym for Seemann Composite Resin Infusion Molding Process), provides many structural benefits that the developers of the process say rival the material and mechanical properties obtained in a highly controlled autoclave process. The infusion process creates a high performance laminate in one shot eliminating secondary bonding problems. The process also provides opportunities to achieve fiber to resin ratios as high as 70:30 along with the virtual elimination of air entrapment and voids. The key to the process is the resin distribution system patented by Seemann Composite Systems, Inc. of Gulfport, Mississippi. In general, the patents center on a flexible cover incorporating a medium for resin distribution along with several important technical features that enable a builder to get repeatable properties from a closed molding system suitable for low volume production. The process requires a mold similar to any open molding process and a unitary vacuum bag (see Figure 4-8). The process, as described in the patents, begins with the fabrication of a bag from silicone rubber to conform to the mold. The silicone rubber compound starts out as a brushable liquid. The bag is made up by Chapter IV Page 55

66 Comparison Vacuum Bagging and Infusion 7acuum Bag Lay-Up Reinforcement materials placed in mold by hand Resin applied by spray or flow coater with some hand rolling and tucking Apply release ply, bleeder, and vacuum bag to cover wet lay-up Applied controlled vacuum to eliminate voids and remove excess resin After cure, remove and dispose of bag materials, bleeder, and release film Release Vacuum nfusion Process - Simplified Specialized fiber reinforcements and core materials placed in mold by hand Apply special bag to cover lay-up Draw a vacuum and introduce resin Control uniform distribution of resin by use of vacuum* After cure, remove and dispose of bag material** l-0 Vacuum Specialized Fiber Reirforce ent T To Vacuum 3 *Some infusion processes also make use of a combination of vacuum and pressure feeding of resin Alternative tooling designs may provide for reusable soft bags or semi rigid covers Mold 4 1 I FIGURE 4-8. A comparison of vacuum bagging and infusion processes. Chapter IV Page 56

67 applying several coats of silicone rubber over a completed lay-up that has been left in the mold. Once the silicone rubber is cured, it can be peeled from the mold providing a tough temperature resistant tailored form that can be reused many times. The bag or form also incorporates some other features such* as open sided resin distribution ducts with branch conduits to provide paths to flow the resin to all parts of the laminate. At the periphery of the bag are vacuum conduits. Each of the major vacuum and resin conduits is provided with an inlet tube for connecting to a vacuum manifold lead or a resin supply tube. In addition, the bag can include a pattern of small pillars, cones, or pyramid shapes formed on the inner surface to hold the bag off the laminate. This provides local paths for the resin to flow to the laminate and covers most of the fiber lay-up except for the perimeter where resin flow is directed into the fiber instead of across it. An alternative to this approach is the inclusion of a mesh or resin distribution media which serves to hold the bag off the laminate. Some of the current applications of this process use disposable bags which are used only once. This approach provides a significant amount of solid waste and is probably justified only for very low volume production. It s apparent that the reusable bag makes sense in terms of economics and waste reduction for sustained production. The sequence of operation for the process begins with laying up the dry fiberglass against the mold in the desired amount and orientation. Coring material is also placed in a similar manner. Some builders use a spray adhesive compatible with the resin to hold the dry fiberglass in place. The vacuum bag with the resin distribution medium is put in place over the dry laminate. Once the system is sealed, a vacuum is then applied and the enclosed mold checked for leaks. After the system has been evacuated, the resin is introduced until runoff in the resin channels indicates that the laminate has been totally impregnated. The mold remains sealed until the resin is cured. After curing, the bag is carefully peeled away and cleaned for reuse. The key objective in the infusion process is to create a conforming bag structure for a specific mold that can be reused without the necessity of laying-in individual distribution media, resin channels, and vacuum conduits each time a part is made in the mold. This reduces waste and minimizes the variability that occurs when a new resin and vacuum distribution system has to be constructed each time the mold is used. Potential Benefits -- The reduction of styrene emissions has been widely reported as a the major benefit from the infusion process. The Hinckley Company located in Southwest Harbor, Maine, was able to reduce its styrene emissions to less than 200/O of previous levels through the adoption of the infusion process. This, coupled with the company s acetone reduction program, earned it an Environmental Merit Award from the U.S. Environmental Protection Agency in The infusion process provides additional benefits for companies producing highly engineered laminates that require excellent mechanical properties. Mechanical properties in terms of tensile, compressive, and bending Chapter IV Page 57

68 strength from the infusion process are comparable to autoclave processing. Void content is virtually undetectable with this process. Economic Factors -- To use the process laminators must acquire a license to use the patents and pay for training covering some proprietary techniques developed by TPI (formerly known as Tillotson-Pearson, Inc.) in Warren, Rhode Island. TPI has collaborated with Seemann Composites to commercialize the process. Each laminator will have to evaluate costs and benefits of the process to determine if this approach to composite construction is economically feasible for their circumstances. Infusion With a Semi-Rigid Cover Structural Composites in Melbourne, Florida, has developed a molding process. called the Resin Infusion Recirculation Method (RIRM). The process is similar to the vacuum bag infusion process but with some significant differences. This molding process begins by placing dry reinforcement material in an open mold. Next a semi-rigid cover containing ports for vacuum and resin connections is. paced over the dry laminate and sealed around the edges of the mold. Once all the appropriate connections are made to the ports the infusion process begins. A vacuum is drawn on the mold to evacuate the air from the laminate. When this phase is complete, the resin is introduced. The supply tank for the resin has a slight over pressure (2-5 psi, gauge pressure) which causes the semi-rigid cover to flex. This flexing opens a gap between the cover and the laminate. The gap provides a pathway for the resin to move across the laminate to insure its complete impregnation with resin. Once the laminate is completely wet-out, the resin inlet is closed and the atmospheric pressure squeezes the cover against the laminate as in the vacuum bag process. The semi-rigid cover, however, provides a smooth surface giving the completed part a second finished surface very similar to Resin Transfer Molding (RTM). The actual difference between vacuum bagging and this process is the use of a semi-rigid cover. This cover can be fabricated from a thermoplastic sheet and vacuum formed using the open mold with a finished laminate left in place. The vacuum formed cover should be transparent so that an operator can visually monitor the progress of the wet-out during infusion. The thickness of the cover is critical since it has to be able to flex at the interface between the resin and the dry laminate while still maintaining its basic form. Potential Benefits -- The infusion process using a semi-rigid cover provides a closed molding system that will eliminate nearly all styrene emissions during the transfer of resin to the laminate. The process also reduces solid wastes since there is no overspray and limited trimming. A significant source of waste in most bagging processes is the disposal of the bag after molding. In this process the cover is not perishable. The elimination of secondary bonding problems is a benefit with this process since the laminate is created in one shot. The process also creates a second side that will have a good finish which in most cases will not require any secondary Chapter IV Page 58

69 finishing operations. And, if the fabrication of the cover is carefully done, the process can furnish a high glass-to-resin ratio providing parts with good, uniform mechanical characteristics. Economics -- This process provides a middle ground between vacuum *bagging and RTM which is discussed in the next section. The advantage this process offers laminators is the opportunity to make and modify their own tooling without having to go to outside sources. This gives the laminator control of tooling costs and more importantly the ability to make changes quickly and economically. This flexibility is not available in RTM and compression molding. The elimination of overspray and bagging material waste provides another reason for considering this process. Type: Company: Location: Case Study No 6 Resin Infusion Recirculation Method (RIRM), Infusion with a Semi-Rigid Cover Structural Composites, Inc Technology Drive W. Melbourne, FL Contact: Scott M. Lewit, President Phone: (407) Purpose: Motivation: Supplier: Payback Period: Comments: source: Reduce styrene emissions Reduce solid waste Provide laminates with improved mechanical properties Ease fabrication Improvement of air quality Improvement of product quality Structural Composites, Inc. Not available The part being fabricated with this process was a battery tray for a commercial vehicle. The tray size was approximately 3 by 5. The tray was a complicated part with several compartments. Part weight, strength, finish, and waste reduction were all factors in applying this process to the production of this part. Structural Composites provides training and assistance in technical transfer to companies ir the composites industry. Plant visit in August, 1994 and phone conversations. Chapter IV Page 59

70 . I....,,._._ :.._,_ 2.<.*_.. -. Resin Transfer Molding (RTM) Fabricators who make fiberglass products can choose from a wide choice of production methods. Open molding spray-up and hand lay-up production techniques are frequently employed by smaller firms or those who produce limited numbers of units from each mold. Open molding carries a high per piece cost due to the labor intensive methods inherent in the process, limited daily output from each mold, and waste. Closed mold technologies may offer a practical alternative to reduce these costs if volume and part design are appropriate. Closed molding operations practically eliminate requirements for atomization of resins and may offer a number of production advantages over conventional approaches to molding. The closed molding technologies most frequently applied to production of fiberglass components are compression molding and resin transfer molding. molding compound FltiUKk 4-Y. Compression molding. - Compression molding can reduce high per unit cost, but only if production volume is high enough to sufficiently spread out the high cost of the matched metal dies. Special molding compounds of resin and reinforcing materials are normally required. The molding compounds are compressed between heated matched mold surfaces (see Figure 4-9). Output is high because the molding compounds cure rapidly in the heated mold. Some materials yield a good finish without application of a gel coat. Both surfaces of the molded product will be as smooth as the mold. Compression molding processes have been used successfully in the automotive industry for more than 25 years. Production output requirements for this type of molding will need to approach 150 parts-per- Chapter IV Page 60

71 mold-per-shift to provide a reasonable base to spread out the costs of molds and tooling. Another closed mold process known as resin transfer molding (RTM) has also been in use for several years. Like compression molding, RTM utilizes matched molds. However, the matched molds do not have to be made of metal, and high pressure mold closing systems are not required. RTM appears to offer many advantages to firms that seek production volumes of 500 to 10,000 parts per year. Resin Transfer Molding Processes -- RTM production systems can be set up to replace many conventional open molding processes. Molds can be produced from the same materials and with the same techniques required for production of conventional molds. The molding resins and filler materials differ little from materials used to produce similar components in open molds. Even the gel coat finishes are the same as those produced in open molding. RTM is carried out in a closed mold at room temperature. Processing begins with the application of a gel coat to one or both sides of the mold, depending on requirements. Glass reinforcing and other materials, such as core stock, are placed in the bottom half of the mold. The mold halves are closed and securely clamped. After the mold is closed, catalyzed resin is injected through one or more strategically located ports. Inlet ports and vents are normally located in the top half of the mold. A diagram of the RTM process is pictured in Figure Resin injection pressures are typically between 30 and 75 psi.. The matched molds are laid-up over a pattern in the same manner and with the same types of materials used to produce molds for open molding. Some specialized tooling is required to insure that alignment and clamping pressure are maintained when the molds are closed. The molds must also be properly reinforced to avoid flexing during the injection and curing cycles. Inlet ports and vents must be properly located so that resin is pumped into all parts of the mold. Mold and tooling quality determine the quality of the part. Potential Benefits -- Pollution output is greatly reduced since application of the gel coat is the only step in RTM that requires atomization of resin. Pumping catalyzed resin into a closed mold virtually eliminates vapor emissions and odor by confining the resins in the mold until curing is complete. There is little, if any, waste of resin. Even dust producing secondary grinding operations are reduced because the closed molding system eliminates most flash removal and edge smoothing requirements. Quality and productivity may be improved through the use of RTM. The molding system produces parts that can have an excellent finish on both sides. Open molding requires at least two molding operations and secondary assembly work to produce parts with two finished surfaces. Since conventional mold making practices can be employed, start-up and tooling can be accomplished quickly and economically once experience with this technology is gained. With complex parts, the lay-up of reinforcing materials, core stock, inserts, and resin can be accomplished in one step. Chapter IV Page 6 1

72 Resin Transfer Molding Sequence Specialized fiber reinforcements and core materials placed in mold by hand. Mold halves closed and clamped shut. Specially formulated resin pumped into the closed mold. Mold remains closed during cure cycle. After cure, part is removed with little or no waste. Upper Mold \ Air&. / En; b Specialized Fiber Reinforcement Lower Mold f;lg UKL: Resin transfer molding. Low molding pressures required for RTM help reduce many expenses associated with other molding approaches. Less energy is required to operate material delivery units. Lower operating pressures reduce the cost and maintenance of pressure lines and fittings. Wear on pumps, accessories, and controls is also reduced. Routine clean-up of the working environment should be needed less frequently. Economic Factors -- RTM applications seem best suited for intermediate volume production of small to midsize components. Large items, such as boat hulls, can be produced using RTM techniques, but tooling costs per unit would be quite high. Items such as restaurant seats, hatches, doors, recycling bins, automotive parts, tubs, and shower units are much better suited to this type of processing. Molds for products of this size can produce parts that require a minimum of trimming, assembly, and secondary finishing. Initial investments in RTM may be returned quickly if there is sufficient volume. In comparison to open molding, potential savings are greatest when production rates are moderately high and both sides of the component must be finished. In situations where product demands are high enough to require increases in productivity, RTM should be explored. Some guidelines in the form of questions are shown in Table 4-2. Chapter IV Page 62

73 TABLE 4-2. Factors for choosing resin transfer molding. If you can answer yes to most of these questions, then you may need RTM. Production requirements 1. Is the part high volume? 2. Need two good sides? 3. Is wall thickness tolerance important? 4. Are delivery dates critical? 5. Need a way to reduce styrene levels? 6. Is floor space limited for high volume production? Secondary operations 1. Are size tolerances critical? 2. Need good fit and match-up? Can you amortize tooling that may be more than ten times as expensive as open mold tooling? Since most intermediate volume processors have limited research and development money, RTM applications have increased at a slow pace. Interest in the technique has remained high as more processors seek ways to improve productivity and reduce waste and pollution. Economies can be obtained by designing the mold used computer aided design software and then turning the design into a mold using a computer controlled machining center. Other economies can be realized by using customized glass fabric made to size for RTM applications. Suppliers of RTM equipment are listed in Appendix C. Units in Use -- RTM has been used on a limited basis by Hatteras Yachts in High Point, North Carolina. The process was applied originally in Hatteras New Bern, North Carolina plant in the production of a rudder assembly for the company s 65 foot sailing yacht. The rudder assembly has curved surfaces on both sides and is cored with a high strength structural foam. The units produced exhibited good structural integrity and surface finish and required little in the way of secondary finishing and no assembly operations. Hatteras Yachts also uses RTM in the production of other products including transom door units for large motor yachts. These 4 inch thick curved doors weigh approximately 15 pounds and have a surface area of almost seven square feet on each side. They must fit uniformly in the openings which are molded into the transom. To insure high strength the units are reinforced with roll fiberglass stock and are cored with structural foams. The units are finished on all surfaces so that both mold sides are gel coated. Chapter IV Page 63

74 Case Study No 7 Type: Company: Location: Contact: Phone: Purpose: Motivation: Equipment Supplier: Payback Period: Comments: Source: Resin transfer molding Yacht door and hatch structures Hatteras Yachts High Point, North Carolina Robert Arthur (910) Reduce material consumption Insure quality Improve productivity Reduction of steps required in lay-up Reduction in finishing operations Rimcraft Technologies 1914 English Road High Point, NC One year In 1986 RTM was introduced to reduce labor for assembly of components, fairing operations, and finishing. Eight years later Hatteras Yachts is still using RTM but on a limited scale. They are currently producing a hinge coaming and a fish (transom) door using RTM. Other parts once considered for RTM are being made with vacuum bagging and thermoforming. These processes witi their less expensive tooling can be justified for low volume production while still providing good fit and finish. Plant visits during November, 1986 and April, Phone conversation October, 1994 Rotational Molding, Examining Thermoplastic Options Products will likely continue to be made by open molding of thermosetting plastics because no other process can meet the design constraints requiring low volume, large part size, critical mechanical performance, and high style and finish. Materials such as polyester resins and fiberglass can be combined in a simple manufacturing system to produce products profitably to meet these Chapter IV Page 64

75 constraints. Molds and tooling are simple, and investments in specialty equipment are considerably smaller than investments associated with other manufacturing processes. Product lead time can be very short, and the process is well suited to the production of prototypes and short product runs. Production related drawbacks of the process, however, include high labor content, long production cycle times, limited daily output per mold, and high pollution potential. Consequently, laminators should consider other materials and methods that may meet the design constraints without the drawbacks. The plastic industry as a whole uses far more thermoplastics than thermosetting plastics. Thermoplastics processing offers faster curing cycles, lower emissions during processing, lower costs per pound of raw material, ease of recycling, and lower labor intensity. Advances in processing technologies and thermoplastic resin systems are causing many in the industry to examine alternative approaches to the molding process. New engineering grades of thermoplastics can be reinforced with fiberglass or other fibers. These materials can rival the strength of many of the strongest thermosets. Production machinery and tooling costs however are still high for thermoplastics forming processes such as injection molding, extrusion, and blow molding. Often thousands of products must be produced in order to provide a reasonable amortization for mold costs alone (large chrome plated steel molds may cost more than $100,000 to produce a part with only a few square feet of surface area). Molds for processes such as rotational molding, however, can be produced at costs low enough to warrant the interest of some open molders. Rotational Molding of Small Tanks Rotational molding is a manufacturing process that produces a rigid or semirigid hollow part by charging a hollow mold with a measured amount of powdered thermoplastic resin. The process begins by charging a mold which is then rotated simultaneously around two perpendicular axes. While being rotated, the mold is subjected to a two phase cycle. During the heating phase the mold is brought to the resin melt point and held at that temperature to melt the resin and coat the interior of the mold. Next, the mold rotation is continued through a controlled cooling cycle. After cooling, the mold halves are opened and the part is removed. Cycle times may be as low as five minutes for small products. Times for larger products with thick walls will be considerably longer. Figure 4-U depicts the basic rotational molding process. Rotational molding provides an attractive alternative to in-plant production of open molded assemblies. Tooling costs for molds are considered to be compatible with tooling costs for conventional molds. Rotation molds for the tanks are produced from inexpensive aluminum castings. Because open molding fabrication and curing cycles are lengthy, a number of conventional molds are required to insure adequate daily output of tanks. Only one rotational mold is required to maintain production. Several companies have replaced fiberglass tanks with thermoplastic tanks using this process. Indications are that the thermoplastic units meet design and performance requirements for strength Chapter IV Page 65

76 and durability. Per unit costs are compatible with open molding on low volume runs and less expensive per unit on high volume runs. FIGURE Rotational molding. Changing from in-plant open molding to rotational molding requires careful study and planning. Changing processes are best done when product redesigns and/or new product designs create a need for new tooling and molds. Chemical and physical properties of thermoplastic tanks are significantly different than those of fiberglass tanks. For this reason basic tank designs will need to be altered along with assembly and installation techniques. Rotational molding is not an answer for all producers of open molded components. The process is best suited to items which are hollow in structure and require uniform wall thickness. Items which are open, relatively shallow in profile, or require inserts and internal structural features are difficult to produce through rotational molding. Replacing in-plant open molding with in-plant rotational molding requires major investments in ovens, materials handling equipment, and specialized processing equipment. Strength and durability properties of many of the plastic materials used for rotational molding may not match properties of materials used in open molding. Appendix C has an equipment supplier listed for this process. Combining Subassemblies to Minimize Waste An effective strategy for waste reduction in the composites industry is combining two different functional components into one thus eliminating the source of one waste stream. A good example of this approach is a patent pending process developed by Structural Composites in West Melbourne, Florida. Structural Composites has created a means to combine flotation foam with a tailored to fit hull stringer system. The product called the PRISMA Composite Preform System replaces the traditional wood stringers that manufacturers glass into the hull of motor boats. Typically these wood stringers serve to stiffen t: w hull and provide mounting points for tanks, engines, and flooring in the boat. The ~~~ Chapter IV Page 66

77 ...,-. -_.---_i _._- Composite Preform System provides a dry fiber-reinforced outer surface that is cast to shape using a two-part self-rising non-cfc urethane foam core. The composite preforms are custom manufactured ready for lamination and can be used in either an open or closed molding system. Stitch-Bonded Glass Fabric Hull Conforming Box Mold Integral Bonding Tabs \ Flotation Foam Cavity - Filled With -_-. Urethane Non-CEC FIGURE Integral stringer and flotation system. To start the process the boat builder has to provide Structural Composites with a boat hull and stringer system (loose). Once received, the first step is to create a set of box molds that accurately conform to the hull, stiffening grid, and the location points for mounting components in the boat. The size of the box molds must also be designed to provide the proper buoyancy for the boat. Once the molds are built Structural Composites is ready to begin production of the replacement stringer system. The original hull and stringer system are returned along with the first preformed system for the boat builder s approval. The production sequence for the stringer system is as follows. First, a custom stitch-bonded glass fabric is laid out on all sides of the box mold. Next a polyester fabric (Trevira) is placed over the layers of glass. This provides a liner of material to which the foam can adhere. Once the box is fully lined, it is closed and clamped in preparation for the foaming operation. The hose delivering the foam is attached, and the foam is injected into the box molds (see Figure 4-12). The heat and pressure developed by the foam that could distort or mar the boat hull is easily handled by the mold. Once the foam is cured, the mold is opened and the glass encased foam stringer is removed. A stringer system is actually a Chapter IV Page 67

78 set of interlocking components. Each component is molded separately and placed in separate plastic sheaths for shipment to the boat builder. Once the foamed core stringer system has been received by the builder, it is ready to be wetted-out with resin and attached to the hull. One of the unique aspects of the system is the extra glass that is provided for attachment to the hull. There is no need to tape the stringer since the glass extends 4-5 from the stringer. Indentations and channels to locate and hold other components are all molded in as part of the process to facilitate the building process. Potential Benefits -- Fabricators can simplify their construction process substantially by adopting this system. The stringer system provides boat builders with a well engineered floatation and reinforcing system that speeds the installation of interior components. The system also provides a reinforcing. system that spreads loads out over wide areas of the hull and can substantially improve hull stiffness. The uniformity of the flotation system and its placement also provides the builder with predictable results. Supplemental blocks can also be provided to precisely fit in areas under a deck to provide needed stability. Economic Factors -- To determine if this approach for creating a molded stringer/flotation system for your boats is profitable; you will have to carry out a comprehensive review of your manufacturing costs. In general, builders of high performance boats ascribe the following for benefits to this system: Provides a well engineered hull reinforcement system that is less labor intensive to install; Creates an integral floatation system; Eliminates foaming operations in the plant; The structural grid serves as an accurate jig to speed the mounting, locating, and attaching other interior components; Eliminates wood as a reinforcement material. These advantages reduce labor costs and provides a means to substantially increase rate of production without increasing the number of hull molds or floor space required. The system also reduces scrap. Case Study No 8 Type: Company: Location: Contact: Phone: Composite Preform System Structural Composites 7705 Technology Drive West Melbourne, FL Scott M. Lewit, President (407) Chapter IV Page 68

79 Case Study No 8 Continued Purpose: Motivation: Material Supplier: Payback Period: Comments: Source: Improve product performance Eliminate in-plant foaming Reduce solid waste Ease fabrication Improvement of air quality Improvement of product quality Urethane foam - Non-CFC BASF and Polyfoam Products Not available The application won Regal Boats a 3rd place ACE Award at the 1994 Composites Fabricators Association national convention. Structural Composites is currently supplying stringer systems to five different boat builders Plant visit in August, 1994 and meeting at the CFA convention in October Low Emission Resins -- Additives Materials Low emission resins also referred to as vapor suppressed resins are chemically engineered to reduce emissions, primarily styrene, which occur while the resins are curing. There is a sizable difference in performance between suppressed and non-suppressed resins in styrene loss per pound of resin used in various processes (Chapter II, Figure 2-2). Currently the styrene monomer makes up approximately 45% of the composition of most general purpose and DCPD polyester resins. High exposure levels to styrene can occur during the course of spray-up, lay-up, and curing. Before the cure cycle is completed, up to 10% of the styrene can be expected to evaporate in as hand lay-up process. The amount of styrene evolved is dependent on surface area, laminate thickness, ratio of resin to reinforcement, temperature, and duration of processing. Vapor suppressed resins will do little to limit emissions created during atomization processes, however, they can make a significant difference in reducing emissions during the curing cycle. In concept, suppressed styrene resins are designed to limit the outward migration of styrene due to normal evaporation and the exothermic process associated with the reaction of catalysts and resins. Resin producers have experimented with Chapter IV Page 69

80 e wax type additives which quickly migrate to the surface of the resin and form a barrier to seal in the styrene. Results in terms of emission reduction were positive. Results related to product quality were less than positive. The waxy residue contributed to delamination and separation of the composite lay-up. Current research emphasis has been directed at development of chemical additives which can block excessive styrene migration without interrupting the bonding structure between resin and reinforcing material or various layers of the laminated structure. There are some additives being sold which claim to reduce styrene emissions significantly. One source claims both styrene suppression and freedom from secondary bonding problems. Fabricators should work closely with their resin suppliers to keep abreast of new developments related to improved resins and additives for styrene suppression. Catalysts Benzoyl Peroxide (BPO) - BP0 has been reported to have a beneficial effect in suppressing styrene emissions. Part of this effect has been attributed to a reduction in gel time and a lower peak exotherm (temperature) while curing at room temperature. This catalyst can replace methyl ethyl ketone peroxide (MEKP) for room temperature curing providing the proper accelerator is used in the polyester resin. Normally cobalt is included as an accelerator for polyester resin catalyzed with MEKP. Cobalt however, is not an effective accelerator for BP0 Therefore if you are considering using BP0 as a catalyst, your resin supplier should be consulted first. UV Curing Resins -- These resins derive their benefits from a photo sensitive curing mechanism. UV light serves as the catalyst for this curing mechanism which was developed over fourteen years ago by BASF, a large multi-national chemical producer. This curing agent or initiator can be used in either vinylester or polyester resins. The curing process involves the decomposition of a photoinitiator by exposure to a particular wavelength of light. Once exposed, the decomposition produces free radicals which trigger the polymerization reaction of the resin. BASF indicates in their technical literature that laminates up to 20 mm in thickness can be cured in one lay-up using this curing mechanism. BASF will license any resin producer to use their initiator. Advantages The resin requires no mixing with catalysts or promoters. There are no limits on processing time hence no pot life concerns. The resin is not temperature dependent for curing. Once the resin is exposed to the proper wave length of light, the resin exhibits fast gelling and short curing times. An example of this type of product is Styrid. Additional information can be obtained from: Specialty Products Company, 75 Montgomery Street, Jersey City, New Jersey 07303, (201) Gapter IV Page 70

81 The cure moves through the laminate starting at the surface and then moving inward. The result is limited exotherm and laminate stress. Evaporation of styrene is reduced because the laminate is sealed from the outside in. Resin not exposed to UV can be returned to storage for re-use. Cleaning costs are less since the material will not cure on tools. Disadvantages The resin can not be pigmented. Only transparent fillers can be added and then only in limited quantities The geometry of the part must allow direct exposure to UV light in order for curing to take place. Laminating with UV Resin - The laminating process can be carried out in normal shop conditions using fluorescent lights. Exposure to direct sunlight, however, will cause the resin to begin curing. Other than that precaution, the process can be carried out as you would any other lay-up method. The laminate will not begin to gel until it is moved outside for exposure to direct sunlight or placed in a room containing UV lighting. The flexibility of being able to place and roll out a laminate without concern for gel time provides manufacturers with a great deal of flexibility in adjusting crew size. The entire part can be laid up and then cured as a complete unit. Larger work can be left wet during a break or interrupted for a short period of time without any adverse effects. Tools and dispensing equipment do not have to be cleaned since the resin is not gelling. Since the resin does not need to be mixed with a catalyst, the resin can be applied effectively with a flow coater or roller without a mixing and metering system. Case Study No 9 Type: Company: Location: Contact: Phone: Purpose: UV Cured Resins International Marine 8895 South West 129th Street Miami, FL Ray Russell, Owner (305) Reduce styrene emissions Ease fabrication Chapter Iv Page 7 1

82 Case Study No 9 Continued Motivation: Material Supplier: Agent: Payback Period: Comments: Source: Improvement of air quality Improvement of product quality SunRez Corporation 1374 Merritt Drive El Cajon, CA (619) Bill Gallop Related Technologies PO Box Orlando, FL (407) Not available Noticeable reduction of styrene odor. The curing system provides total operator control on GEL time. Exotherm is also well controlled even on thick sections. Plant visit in August, 1994 and conversations with resin supplier agent (September, 1994) Economic Factors -- The cost for including a UV curing mechanism in a polyester or polyvinyl resin is about $50 per pound of resin. For high volume polyester resin users this nearly doubles the cost of the resin. The savings that can be realized from improved manufacturing flexibility and reduced styrene emissions in some circumstances may justify the additional cost. For large volume users other alternatives may prove to be more profitable in gaining similar benefits. Low Styrene Resins Traditional general purpose (GP) othro type polyester resins were widely used by the industry into the early eighties. These resins had approximately % styrene content by weight. By the mid eighties DCPD (dicyclopentadiene) resins became popular because of improved cosmetics due to reduced shrinkage and their cost competitiveness. DCPD blends currently have a slightly lower styrene content. However, in 1988, rule 1162 (A South Coast Air Quality Management District VOC regulation) required composite manufacturers located in a four county area in Southern California to adopt resins with a styrene content no greater than 35%. The tough low profile (TLP) resins which are available to meet rule 1162 have a 33.5 to 35% styrene content. Reichhold Chemical, a producer of Chapter IT. Page 72

83 r / resins for the marine industry, indicates that the flexural fatigue properties deteriorate quickly when styrene levels drop below 33.5 %. Nevertheless, the future according to one resin supplier is no styrene. The styrene monomer will probably be replaced in the resin by a more environmentally acceptable monomer. The replacement, however, will likely to be more expensive and require laminators to develop new techniques to handle the styrene free resins. Laminating with Low Styrene Resins - Currently, low styrene resins are readily available and in use in Southern California. The most notable characteristic of these resins is the higher viscosity. This makes it more difficult for the resin to wet a surface and saturate glass fiber. Reichhold indicates that the molding surface and glass fiber should be coated with resin and allowed to wet-out 45 seconds before roll-out to give the resin a chance to interact with the binders and surface. Achieving good secondary bonding has also been mentioned as a problem because of reduced styrene levels. This is due in part because the low styrene resin is less forgiving of dust and contaminates on the laminate surface. Therefore, more attention has to be paid to surface preparation as well as following good wet-out procedures. Resin Storage A number of approaches are utilized for purchasing resins for molding operations. Many processors elect to purchase all materials in 55 gallon drums, while others prefer to purchase resins in bulk quantities. Large firms, such as bath fixture manufacturers, purchase practically all their resins in bulk and store these materials in large storage tanks. Smaller companies, however, usually purchase their laminating resins in drums. Specialty resins such as gel coat colors, tooling resins, and fire retardant resins are almost always purchased in drums. When large quantities of resins are consumed, bulk systems offer companies several advantages, particularly lower prices. Lower prices are possible because of quantities purchased, elimination of packaging in the form of barrels, and ease of handling in terms of loading and unloading. Bulk systems are well suited for delivering large quantities of resins to vats for mixing with fillers or other additives. The purchase of drums, however, offers smaller users flexibility to meet seasonal demand in terms of quantities purchased which enable them to maintain fresh stocks. Furthermore, drums do not require installation of expensive storage tanks, resin delivery pumps and piping, and the need periodic storage tank clean-up. Drums do create some problems. A systematic approach to inventory, control, and disposal must be established in order to assure that resins are used before their storage life expires. To maintain uniform properties agitation is needed to prevent stratification particularly if the material has been on hand over two weeks. Even small FRP operations will collect drums at a rapid rate, and it may be difficult to dispose of them. Many landfills refuse to accept drums and particularly drums containing liquids. Disposal of drums containing liquid residue may require handling the drum as a hazardous material. Storage of full Chapter IV Page 73

84 drums and empty ones is also a problem. Considerable floor space is required for storing large quantities. Again to maintain consistent properties the resin drums should be stored at a constant temperature between 72-78OF, and should never exceed 80 OF. Use of drums normally implies a commitment of labor to materials handling. Drums must be transported from the delivery truck to the storage area, from the storage area to the point of use, and then from the point of use to the storage area. Manholes Breather Vent & Clama Armc+nr m Agitator Return Line 1 l-l II I A I I SUPPlY Line Valve Blowout. - Containment Dike Mild steel Underwriters Laboratories (U.L. 142) approved storage tank with epoxy liner or steel tote tank. Bottom and top entry manholes (24 ) for tank inspection and agitator maintenance. Return lines direct to bottom of tank to avoid static buildup. Electrically ground all lines and tank. Temperature controlled enclosure or insulated tank and temperature controlling medium required. FIGURE Resin storage and delivery system. Chapter IV Page 74

85 c Mini-Bulk Resin Storage - Fabricators can choose an intermediate approach to resin storage that offers some of the advantages of both the bulk and barrel strategies. This method uses special containers which are large enough to supply several hundred gallons of resin, but small enough to be handled by a small forklift. These containers form the heart of what is referred to as a mini-bulk resin system. The mini-bulk system uses reusable stainless steel containers or disposable (fiber box exterior with a polyethylene bladder) containers which are shipped to the user by truck. Since the units can be stacked, floor space dedicated to resin storage can be reduced significantly. When new shipments of resin arrive, the empty reusable containers are returned to the supplier. The tanks are then steam cleaned and refilled for delivery. The disposable tanks offer some waste disposal problems but not to the extent posed by barrels. This form of resin storage has some disadvantages as well. The problems are primarily in maintaining the uniformity of the stored resin. These containers do not offer a practical means for agitation. In the case of the disposable tote, the head opening does not allow a normal drum agitator to be used. In the cases where agitators can be fitted, the configuration of the tote prevents the mixers from adequately stirring the contents. Therefore, a recirculation system is essential even for mini-bulk storage. Tote users should inspect the tote contents prior to use to insure that stratification of the contents has not taken place. Bulk Storage Systems - Fixed storage tanks are very useful and economical for large volume users. These tanks can be either vertical or horizontal. Vertical tanks have some advantages since they are easier to agitate and provide less surface area exposed to the atmosphere. Stainless steel (type 304) is the recommended material, and it should be phenolic or epoxy lined if promoted polyester resins are being stored. Do not use copper or brass fittings because these metals react with polyester resin and create compounds which may effect the cure, color or shelf life characteristics of the resin. Aluminum and stainless steel fittings are preferred. Figure 4-13 shows an outline of the basic components of a bulk storage system. Resin Circulation System The bulk resin systems offer a number of positive features. Inventory, product control, and record keeping are easier to manage. Products can be tied directly to the resin batch used in their lay-up without resorting to extensive record keeping and drum labeling. There is no mixing of different batches from different barrels or including a barrel of out-of-date material with good resin. There are also no partially used barrels to dispose of or store. However, a bulk storage system requires agitation and a means to circulate the resin from the storage room to the laminating area. The resin distribution system typically consists of a closed loop plumbing system which is used to circulate resin to all areas of the facility. A circulation loop is required to prevent resin from solidifying in piping serving areas where resin is used infrequently. During plant operating hours resin is continually circulated and returned to the storage tank. This action helps keep the resins mixed and maintains temperature control of the resin. A positive Chapter IV Page 75

86 I ; _II I I - displacement pump is ideal for resin delivery. A diagram of a bulk storage delivery system is shown in Figure It should be noted that regardless of the type of resin distribution system, barrels or storage tanks, the resin should be stirred and temperature controlled. Many resin suppliers also recommend an inert atmosphere be established inside the tank. With good temperature control this inert blanket can inhibit color degradation and polystyrene buildup. I I Resin circulates in a continuous flow to all plant lay-up areas FIGURE Kesin storage and delivery system. A mini-bulk system was installed at Privateer Manufacturing, in Chocowinity, North Carolina, in This system has functioned efficiently in this facility. The stainless steel tanks measure 42 inches X 42 inches X 55 inches and have a capacity of 300 gallons. The resin tanks and resin are supplied and shipped by Inland Leidy, Inc.. Tanks are unloaded with a small forklift and stored inside the main production area. One central resin supply loop and pump are used to distribute resin to a number of outlets in the adjacent lay-up area. On a per pound basis resin prices are the same as for drum shipments. Other cost saving factors have emerged. Since less floor space is required, inside storage of resin is possible. This approach helps keep resins warm in winter and promotes faster and better curing. Time lost to handling resin drums has been greatly reduced, and production interruptions due to empty resin drums are eliminated. The company owner indicated that installation costs for the resin distribution system were recovered in less than a year. Chapter IV Page 76

87 _ v--i _ Ad A- _-..-- L_I-L-,l;_I - >A Type: Company: Contact: Phone: Purpose: Motivation: Equipment Supplier: Payback Period: Comments: Source: Case Study No 10 Mini-Bulk resin storage system Privateer Manufacturing, Inc. Location: I? 0.69 Chocowinity, NC Warren Wilkerson, President (919) Reduce barrel storage of resins Improve worker productivity Fewer barrels to dispose of Simplification of record keeping Reduction of operating expenses Resin tanks and resin Inland Leidy, Inc. 900 S. Eutaw Street Baltimore, MD Resin distribution equipment Rimcraft Technologies, Inc English Road High Point, NC Less than one year Drum disposal problems were greatly reduced. Productivity was improved significantly. The labor required for material handling was reduced. Plant visits in August, 1986 and April, 1987 and phone conversations with plant manager and equipment supplier: (March, 1987). Several years later the plant was closed and partially relocated. Mr. Wilkerson indicated in follow-up conversations in December of 1994 that the mini-bulk resin storage system was a worthwhile investment and provided all the benefits anticipated. Chapter IV Page 77

88 -..-,,..a.> 9 d. I.._.;._w _;_---..I I Chapter IV Page 78

89 Solvent Use CHAPTER V Managing Contaminated Solvents Acetone and other similar solvents for general cleaning are being replaced in most open mold fabricating plants. These solvents were widely used to remove uncured resins from spray equipment, rollers, brushes, tools, finished surfaces, and the hands of employees involved in lay-up operations. Since these solvents become contaminated with residue from resins and catalysts, they fall under strict governmental regulations (see Chapter 3). Precise records must be maintained on the delivery, storage, and disposal of these solvents. Disposal of contaminated solvents represents a major expense in payments for hazardous waste removal and disposal. Prices for transportation and storage can exceed $400 per barrel for moderately contaminated waste. Given the RCRA cradle-tograve philosophy regarding waste generation, the expenses may not end with payment of invoices for shipping and disposal. Long-term liabilities and responsibilities for problems that might evolve from storage of contaminated solvents must also be considered. Recent findings supported by the EPA indicate that acetone has negligible photochemical reactivity. Consequently, acetone may be redefined as a nonvolatile organic compound (VOC) and deleted from the list of toxic chemicals subject to reporting under the Toxic Release Inventory (TRI). However, acetone would continue to be treated as a hazardous chemical under RCRA and the Clean Water Regulations. Deleting acetone from the list of toxic chemicals subject to section 313 of the toxic release inventory reporting requirements under the Emergency Planning and Community Right to Know Act (EPCRA) of 1986 would in many cases significantly reduce the reported amount of toxic pollutants being discharged from fiberglass plants. Nevertheless given the status of current regulations and rising solvent costs, alternative solvent systems should still be considered. There are several approaches that are proving effective for the fiberglass industry. The most popular approach is adopting a replacement cleaner that can be safely disposed of in municipal sewers. However, solvents can not be handled in this manner. Therefore, in the case of solvents, recycling is the most viable option since it effectively concentrates wastes and returns usable solvent to the laminator. Alternatives to Acetone There are two groups of acetone replacements that have emerged as effective alternatives for laminators. Unfortunately, most laminators will probably have to use both while still retaining the use of a small amount of acetone for special cleaning problems. The first group consists of high flash point solvents which on the whole significantly reduce the risk of fire when compared to acetone. Some of the most popular solvents in this group are: Diacetone Alcohol (DAA), Chapter V Page 79

90 . Dibasic Ester (DBE), N-methyl Pyrrolidone (NMP), Propylene carbonate (dioxolanone). These solvents are more expensive than acetone. But because they are less volatile, they have a longer usable life. Also, most of these solvents can be effectively recycled. Consequently, many of the solvent suppliers are able to provide recycling services or can recommend a source for recycling. The second group of acetone replacements is water-based resin emulsifiers or detergent cleaners. These cleaners are good for washing hand tools, brushes, and equipment. To use these cleaners effectively, a company will have to provide wash tanks (heated tanks improve cleaning action) and fixtures to facilitate soaking and scrubbing tools. These tanks can be quite inexpensive and are easily fabricated in a maintenance shop. One plant used five gallon buckets with each one fitted with two scrub brushes permanently mounted on a rack suspended in the bucket. This arrangement provided a means for soaking tools and using the mounted brushes for scrubbing off the residue that remained after soaking. Once the tools are clean, they can be dried by dipping the tool or brush in a small pail of acetone. Because the primary cleaning is done by the resin emulsifier, this small quantity of acetone is changed very infrequently. Although this cleaning process is more complex than using acetone alone, it has some significant safety and cost advantages. One of the major advantages is disposing of waste. When the tanks are emptied, the liquid (the solids in the bottom of the tank are trapped and disposed of separately), can be discharged into a sanitary sewer. However, before this is done a company must notify the municipal authorities and receive their permission to do this. Your municipality may require some testing, but this is neither difficult to do nor prohibitively expensive. The cost of the material is also a factor for switching away from acetone. Most resin emulsifiers are very economical when diluted with water to their working strength. Case Study No 11 Type: Company: Location: Acetone Replacement in a Fiberglass Laminating Operation Carolina Classic Manufacturing Co. 510 East Jones Street Wilson, NC Contact: J. N. Eason, Vice President of Manufacturing Phone: (919) Chapter V Page 80

91 Case Study No 11 Continued Purpose: Motivation: Equipment Supplier: Payback Period: Comments: Replace acetone Reduce fire hazard Reduce storage of waste Reduce consumption of solvents Eliminate emissions and fire hazard Water-based resin emulsifier Insco 195 Cleaner (800) 849-l 133 Solvent replacement Superior S-280 Indianapolis, IN (317) NA Carolina Classic reduced their acetone usage by switching to a high boiling point solvent and a water-based resin emulsifier in As a result, acetone emissions decreased 50%, and hazardous waste generation dropped more than 70% during the first year. The reduction in acetone usage still continues. In 1991 the plant used.0148 pounds of acetone per square foot of product laminated. In 1994 this rate decreased to.0071 pounds per square foot of product produced. Source: Plant visit on November 2, 1994 In-Plant Solvent Recovery Small Batch Solvent Distillation Equipment -- Some fiberglass fabricators in North Carolina are finding in-plant batch type distillation systems to be a cost efficient approach for dealing with contaminated solvents. Batch type units have proven to be successful in meeting the needs of firms producing small to moderate quantities of contaminated solvents such as acetone. Unit sizes commonly available range from 5 to 55 gallon units. A basic batch type system consists of four major components: a contaminated solvent collection tank, a heated boiling chamber, a condenser, and a clean, Chapter V Page 8 I

92 solvent collection container. A typical low cost system is diagrammed in Figure 5-l. The operating systems for these units are typically contained within a single compact cabinet. Space required to house a unit is generally less than the space required for storage of virgin solvents and contaminated waste. COOlbIg water J II -1 valve boiling chamber FIGURE 5-l. Basic batch solvent distillation system. Small quantities of contaminated solvents are poured into the solvent collection tank during normal employee clean-up operations. The contaminated solvent collection tank should have an inlet that can be properly sealed to prevent evaporation. A filtering screen should also be placed in the inlet collection system to prevent solids and sludge from clogging pumps and/or feed pipes which deliver contaminated resins to the heat chamber. If the collection tank is situated higher than the top of the heat chamber, piping and valves can be permanently installed so that solvent can be gravity fed into the heat chamber. If the collection tank is not located above the heat chamber, a pumping system may be required to transfer solvents for processing. The heat chamber is designed so that a vapor tight seal can be maintained during heating and cooling cycles. In the chamber contaminated solvents are heated to a predetermined vaporization temperature, and these vapors are channeled out of the container to an external condenser. Heat can be supplied by means of electric elements or by steam coils. Steam units offer some advantages in terms of speed and safety. If the plant does not have steam available, a boiler can be supplied by the manufacturer of the still. The heat chamber will also be equipped with a means to collect the unusable residue which has been separated from the reclaimed solvent. This residue is referred to as distilled bottoms or still bottoms. Chapter V Page 82

93 Depending on design requirements, condenser units may be water cooled or air cooled. Water cooled units are generally more compact and more efficient but require connection of external water inlets and drains. In the condenser, vapors are cooled rapidly in order to promote condensation. This condensate is clean solvent and is drained off and collected in appropriate containers. These collection containers may be either a permanently piped in bulk storage unit or simply conventional barrels. The solvents collected in this manner are generally ready for use without further treatment or additives. The distillation recovery option seems particularly appealing since Federal EPA regulations (Regulation 40 Part 261.6) do not require a permit for this type of solvent treatment. However, the North Carolina Solid and Hazardous Waste Management Branch must be notified when a solvent distillation unit is installed. There are a number of cost factors affected by the use of batch distillation units. In comparison to conventional disposal techniques, the quantities of solvents which must be disposed of by hazardous waste handlers may be reduced by as much as 90%. Since usable solvents are produced, the outside purchase of virgin solvents can be dramatically reduced. Long-term liabilities for waste disposal are also significantly reduced. The units do require a considerable initial investment. Prices may vary from approximately $5,000 for a basic 5 gallon per batch unit to more than $40,000 for a relatively sophisticated 55 gallon unit with labor saving automatic control systems and pumps. Stills also require energy for heat, some labor for operation, and water for the condenser. These operating costs will generally be less than 50~ per gallon, with some manufacturers claiming costs under 204 per gallon. Other expenses include disposal of still bottoms, bags, and maintenance. Batch type distillation systems do not require full-time operators or extensive operator training. With the most basic design an attendant is normally assigned the duty of filling the heat chamber with contaminated solvents, sealing the unit, activating appropriate controls, deactivating the controls after the cycle is completed, and removing the residue distilled bottoms from the heat chamber. The complete cycle time normally ranges from six to eight hours, but the operator need only be present during start-up, shutdown, and clean-up. Supplies consumed in the processing of solvents are usually limited to disposal bags. The addition of automatic controls and pumping systems to load waste solvents can greatly reduce labor demands and prove greater assurance that the unit will be shut down if an operational problem occurs. A diagram of a larger unit with automated controls is shown in Figure 5-2. Fountain Powerboats in Washington, North Carolina, has used a Recyclene model RX-35, supplied by Southern Recovery Company, for several years. The unit features a number of automatic control systems for materials handling, cycle control, and safety. Liner bags are used to collect still bottoms and keep the boiling chamber clean. Total operator time required for each cycle is only 12 minutes. Selection and installation of a batch type distillation system requires careful study and planning. Suppliers listed in Appendix C will normally provide expert Chapter V Page 83

94 advice about the systems they carry. Demonstrations of equipment should be carried out using representative samples of contaminated solvents from your facility. Insurance requirements, safety, and fire codes should be taken into consideration before a system is selected and installed. Vapors produced during distillation can be highly flammable, so units and surrounding equipment should be of an explosion proof design. Results may be disappointing on solvents which have been heavily contaminated with water or other elements with high vaporization temperatures. / condenser C(Dntaminated recovered recovered solvent / I aitoma tic heat and automatic distilled bottoms water controls fill system collector FIGURE 5-2. High efficiency batch distillation system. Case Study No. 12 Type: Company: Location: Contact: Phone: Purpose: Motivation: In-plant batch distillation unit Fountain Powerboats P. 0. Drawer 457 Washington, NC (9 19) Reduction of waste disposal costs Reduction of solvent costs Reduced hazardous waste storage and disposal Reduction of expenses Chapter V Page 84

95 -,. _.a...*.<,.. \,\, :* -;... _ r -:.,-.- -;-:.- -. :.*; L 2 ;. -em,::.->: -....*,- ~. ---L---.-L L- AriLi Case Study No. 12 Continued Equipment Supplier: Payback Period: Comments: Southern Recovery Co. P. 0. Box 3279 Fort Mill, SC (803) Less than one year Unit is cycled at least once per work day. Approximately 90% of the contaminated acetone is recovered. Operator time required is less than 15 minutes per cycle. Hazardous waste shipments and solvent purchases have been reduced by at least 75%. Source: Plant visit (May, 1987) Continuous Feed Distillation Equipment While batch type solvent recovery units may prove to be successful in meeting the needs of many North Carolina firms, large volume producers of contaminated solvents may find continuous feed distillation equipment better suited to their requirements. Recovery output for continuous feed systems which are commonly available can range from 250 gallons per shift to as much as 200 gallons per hour. A continuous feed distillation system requires all of the major components included in a batch type distillation unit plus more elaborate controls and materials handling equipment. An automatic pumping system is required to transfer contaminated solvents from the collection tanks or drums to the boiling chamber. Condensers may be either water or air cooled. The clean solvent collection system must be equipped with a monitoring system to avoid dangerous spills created by overflows. With continuous feed systems contaminated solvents should be collected in a centralized solvent collection tank as a part of normal operational activities. Contaminated solvent collection systems should be equipped with a device to prefilter solids and heavy gels. The collection system should be properly sealed to prevent evaporation and made of conductive materials to insure proper grounding. The heat chamber of a continuous feed system will normally be loaded by an automatic pump system. Some designs allow for overriding of automatic loading systems so that batch processing can be carried out. Heat is normally Chapter V Page 85

96 supplied by means of electric heating elements or steam coils. As with batch type distillation equipment, the heat chamber will also be equipped with a means to facilitate collection of the unusable residue which has been separated from the reclaimed solvent. The units can also be equipped with vacuum attachments which allow for recovery of a higher boiling point solvents which are taking the place of acetone. Just as with batch type units, there are a number of cost factors to be considered in the selection of continuous feed distillation units. In comparison to conventional disposal techniques, the quantities of materials which must be disposed of by hazardous waste handlers may be greatly reduced. Since usable solvents are produced, the outside purchase of materials can be dramatically reduced. Long-term liabilities for waste disposal are also reduced. The units do require an initial investment that is much larger than that for smaller batch type units. Installatidn costs for large units are likely to exceed $50,000. These types of units are not likely to be justifiable for firms with recovery needs of less than 100 gallons per day. Because of the major capital investment required, selection and installation of continuous feed distillation systems requires careful analysis and planning. Suppliers listed in Appendix C will normally provide expert advice about the merits of the systems they carry. Merits of the units available should be evaluated on the basis of compatibility with company needs. Demonstrations of equipment should be requested and carried out using actual samples of contaminated solvents taken from the facility. Insurance requirements, safety, and fire codes should be taken into consideration before a system is selected. Because acetone vapors produced during distillation can be highly flammable, the units and surrounding equipment should be of an explosion proof design and well ventilated. Your solvent supplier can provide additional information on distillation processes particularly if you are planning to reclaim an acetone replacement solvent. Ongoing Developments -- Solvent distillation processes are steadily improving. Equipment manufacturers are highly competitive in research and development as well,as marketing approaches. Firms that have experienced poor results with older in-plant distillation processes will find that the newer designs offer efficient processing, reliable control systems, improved materials handling systems, and less operator involvement. These units also feature many improved safety features. Out-of-Plant Solvent Recovery Recycling Agreements -- Some North Carolina fiberglass fabricators are successfully using supplier based solvent recovery as a cost efficient means of dealing with contaminated solvents. In firms where in-plant-recycling has not proved feasible or gained favor with management, successful arrangements have been made for outside recovery of solvents. Often these arrangements are made with solvent suppliers who can reclaim the contaminated solvents at a cost Chapter V Page 86

97 considerably lower than the cost of producing virgin materials. Contracts and arrangements for these services take a variety of forms. In some cases toll arrangements are made to insure that the waste generator s solvents are handled separately. The reclaimed solvents are then returned to the generator along with virgin stock. This arrangement helps reduce the likelihood of solvents becoming contaminated by undesirable substances produced by other waste generators. Some firms have developed service agreements which do not place restrictions on the source of the reclaimed solvents which they purchase. Other companies may elect to specify the purchase of virgin materials only. Separate arrangements, whereby new solvents are purchased from one source and contaminated solvents shipped to another firm, are also common Features of Out-of-Plant Recycling -- As with in-plant recovery techniques, outof-plant recycling requires an efficient management and control system. Contaminated solvents must be collected in tanks or drums as a part of normal employee clean-up operations. The contaminated solvent collection system must be carefully monitored. A filtering screen should be placed in the inlet collection system to separate solids and sludge. The collection tank, or drums, should be sealed to prevent evaporation and contamination. Water and trash will drive up the cost of recovery. Where more than one type of solvent is used, special care must be taken to prevent mixing of dissimilar materials. Each container should be clearly marked with a chemical identification label and a permanent tag. The label on the waste container should include composition and the method by which the waste was generated. A record of this information should be maintained for each container and kept in a central location. Containers should not be labeled as waste unless the materials they contain are no longer in use. In order to avoid requirements for special permits, a management system should be developed to assure that containers are not kept in storage for more than 90 days. Drums should also be stored in a manner that protects them from the weather and physical damage. Leaking drums are a major source of contamination of storm water run off from a plant site. Drums must be in good physical condition or they will not be accepted by the waste hauler. Out-of-plant recovery has a number of drawbacks. Shipment of solvent waste must be carried out by a licensed transportation firm. The waste generator s responsibility for the contaminated solvent does not end when it is loaded on the truck. The RCRA cradle-to-grave philosophy places ultimate liability for proper handling and disposal of waste with the generator of that waste. For this reason short-term transportation liabilities and long-term disposal liabilities have driven up insurance costs. Selection of a recycler and transportation firm should be done with care. A number of waste management companies have ceased operations due to legal actions against them or bankruptcy. Failures of this type frequently result in clean-up and dump site management costs being passed on to the waste generator. This may occur years after the waste has been shipped. The waste Chapter V Page 87

98 management firm s financial status and approaches to handling incineration, still bottoms, and storage should be thoroughly investigated before any business agreements are reached. Hatteras Yachts in New Bern, North Carolina, has elected to use supplier based solvent recovery as the primary means of managing and disposing of contaminated solvents. Hatteras buys acetone in bulk and a proprietary nonflammable chlorinated solvent in 55 gallon drums from The Prillaman Company in Martinsville, Virginia. The company also purchases clean drums from Prillaman for the purpose of collecting and shipping contaminated acetone. Contaminated chlorinated solvents are also collected and shipped back to Prillaman in drums. Prillaman charges Hatteras $10.00 for each clean barrel and issues a credit of $6.00 when the solvents are returned for recycling. The net cost to Hatteras for disposal of each drum of contaminated solvent is $4.00. The company does not purchase reclaimed solvents from Prillaman but does have an agreement for purchase of virgin solvents. Hatteras feels that this arrangement provides for satisfactory disposal of waste at a reasonable cost and insures delivery of a good SUDD~V of high oualitv solvents. Case Study No 13 Type: Company: Location: Contact: Phone: Purpose: Motivation: Service Supplier: Payback Period: Supplier based solvent recovery Acetone and high boiling point solvents Hatteras Yachts 110 N. Glenburnie Road New Bern, NC Andy Misky, Jr., (919) Reduction of waste disposal costs Manager, Facilities Engineering Limiting ion,o-term liability for waste disposal The Prillaman Company (703) P. 0. Box 4024 Martinsville, VA Immediate in comparison to other out-of-plant methods. Chapter V Page 88

99 Case Study No 13, Continued Comments: Source: The Prillaman Company will take contaminated nonchlorinated solvents for distillation at their facility. The distilled solvent is sold for reuse under name of Rock solvent. Plant visits during November, 1986 and April, and phone conversations with the Prillaman Company in December, Incineration of Contaminated Solvents Incineration is also an option for disposing of contaminated solvents, such as acetone. Acetone can serve as a fuel source for heat recovery because of its high BTU value and low halogen content. In some industries, companies have installed in-plant incinerators to bum waste solvents. Chapter 3 discusses some of the regulatory issues that a manufacturer must deal with in order to lawfully incinerate waste. Generally in-plant incineration is too expensive in both equipment and administrative costs to be profitable for most open molders. Therefore, out-of-plant incineration may be more attractive to molders. Waste solvents may be sent to cement or light aggregate plants for use as a fuel. This option may be particularly attractive to small producers. Companies, such as Oldover Corporation, can send their trucks to the customer s facility, to pick up waste solvents. These waste solvents must be pumpable. Collection can be made from large tanks or drums. Cost per gallon for the service is somewhat dependent on the nature of the waste collected. When high BTU value is maintained, costs are reduced. Some contaminants, such as halogen, can prevent the solvents from being disposed of by incineration. Still bottoms may also be disposed of by incineration. Burning contaminated solvents and/or still bottoms in an aggregate or cement kiln produces no ash. This effectively relieves the generator from further liability, since no solid or liquid waste remains. Just as with out-of-plant recycling, out-of-plant incineration requires an efficient management and control system. Contaminated solvents must be collected in tanks or drums as a part of normal employee clean-up operations. The contaminated solvent collection system must be carefully monitored. A filtering screen should be placed in the inlet collection system to separate solids and sludge. The collection tank or drums should be sealed to prevent loss of BTU value through evaporation and contamination. Water and trash will also drive up the cost of the service. Record keeping obligations are not relieved simply because solvents are being collected for incineration. Each container of solvent purchased should be accounted for. Containers should be clearly marked with a chemical Chapter V Page 89

100 L identification label and a permanent tag. The label on the waste container should include composition and the method by which the waste was generated. A record of this information should be produced for each container and maintained in a central location. Containers should not be labeled as waste unless the materials they contain are no longer in use. In order to avoid requirements for special permits, a management system should be developed to assure that containers are not kept in storage for more than 90 days. If drums are used for shipment of waste, they must be in good physical condition or they will not be accepted by the waste hauler. Transportation remains a drawback of out-of-plant incineration. Shipment of solvent waste must be carried out by a licensed transportation firm. The waste generator s responsibility for the contaminated solvent does not end when it is loaded on the truck. The RCRA cradle-to-grave philosophy places ultimate liability for proper handling and disposal of waste with the generator of that waste. For this reason short-term transportation liabilities are not relieved. Selection of a waste management or transportation firm should be done with care. A number of waste management companies have ceased operations due to legal actions or bankruptcy. Failures of this type frequently result in clean-up and dump site management costs being passed on to the waste generator. This may occur years after the waste has been shipped. The waste management firm s financial status and approaches to handling incineration, still bottom, and storage should be thoroughly investigated before any business agreements are reached. Ideally, the waste generator should inspect the incineration facility and observe the operations carried out there. A system for either reclaiming all barrels shipped or insuring their absolute disposal is desirable. This step may help assure that the waste generator does not bear the expense cleaning up waste placed in these containers, at a later date, by another generator. Records related to collection and disposal of the waste should be maintained forever. A form that would be useful for internal record keeping and tracking of solvents is pictured in Figure 5-3. Chapter V Page 90

101 c 4 FIGURE 5-3 Internal record for tracking waste solvents and disposal. Chapter V Page 9 1

102 Chapter V Page 92

103 CHAPTER VI Management and Facility Based Pollution Reduction Process Control Strategies Strategies An effective approach to waste reduction is process control. Although process control focuses on hardware, it is in reality a management technique for controlling variability. Variability is the most common cause for waste and rework in manufacturing. In many cases excessive variability can be caused by a lack of operator knowledge or experience. However, many processes are difficult to control because there is no direct feedback to the operator. Consequently a process that relies heavily on the skill and experience of the operator is therefore inherently variable unless there is some feedback to guide the operator. The process of driving a car on a highway has been used to illustrate how process control works in these situations. Consider a driver keeping an automobile in its lane on a two-lane highway. If the car is in good shape mechanically, the driver is experienced, the day is clear and bright, and the road is straight, then staying in the right lane is easy. However, if the road begins to twist and turn and visibility decreases it becomes more difficult to stay in the lane. To maintain speed (production) the driver needs more road width or well lighted markers showing where the road is going. Now consider one of the most critical production processes in laminating -- gel coating. In gel coat spraying getting the proper thickness is difficult to achieve. Consequently, many laminators spray on more gel coat than is needed to insure there are no thin spots. This approach is adding more material than needed (increasing waste and reducing profits) to prevent the customer from being short-changed on quality. In gel coating, once the bright base color of the mold is covered with 5 or 6 mils of gel coat the visual guides are gone for the gel coat sprayer. The operator is now spraying blind. Consequently, to keep the process in control the operator like the driver, needs to have some markers or guides. For a particular mold the operator can use a wet film gauge to measure the thickness of the gel coat. This is useful in gaining experience, but in a production setting stopping to measure wet film thickness is awkward. Therefore, a marker or running guide is needed. Most gel coat spraying is done using a positive displacement piston pump which makes a distinct sound when it reaches the end of a stroke. Each stroke indicates that a precise amount of gel coat has been sprayed. Consequently, there are a specific number of pump strokes needed to-provide a definite mil thickness on a particular portion of a mold. If this volume is known, the operator can count the strokes of the pump while spraying that section of the mold and be reasonably confident that the right thickness has been obtained. Another way to Chapter VI Page 93

104 Gel Coat Control: Hull Application MARINE MANUFACTURING INC. Model # Serial # Date Operators Zone-A 1 Zone - B I Zone - C I I Gel Pump Strokes/Time Standard Strokes Zone A Zone B Zone C Actual Strokes Standard Time Ac tuai Time Gel Zone A Zone B Zone C Mils Range Range Range Standard l l Actual / NOTES FIGURE 6-1. Gel coat control form for a hull application. Chapter VI Page 94

105 -- _ _- -_.-_.-.-A.L.~L-.~ - _-. -- _-._ Gel Coat Control: Deck Application MARINE MANUFACTURING INC. Model # Serial # Date Operators Zone-A 1 Zone-B i Zone - C I I Gel Pump Strokes/Time Standard Strokes Actual Strokes Standard Time Actual Time Zone A Zone B Zone C I I I I I I I I I Gel Mils Standard Zone A Zone B Zone C ( Range / Range Range fl ,+l zkl Actual NOTES FIGURE 6-2. Gel coat control form for a deck application. Chapter VI Page 95

106 MARINE MANUFACTURING INC. Gel Coat Control: Small Part Application Part name Model # Serial # Date I Zone-A i Zone - B op erators Gel Pump Zone A Strokes/Time I Standard Strokes I I I Actual Strokes I II Standard Time Zone B Actual Time NOTES FIGURE 6-3. Gel coat control form for a small part application. Chapter VI Page 96

107 look at this is to consider the sound of the pump stroke as the rate or tempo for applying the gel coat. To create these guides or rates an operator is going to have to record the pump strokes and the resulting wet film thickness on a worksheet for the first parts being made from the mold. An important part of the recording process is associating the pump strokes with zones on the mold. Therefore, it s important to sketch the mold outline and the zones on the worksheet to develop the information needed. A key part of this technique is identifying zones that match up with good spraying practice. Filling out the worksheet initially may seem tedious, but it is a one time set-up to learn how to spray ( drive ) the mold. After the worksheet is filled out it becomes the process guide for providing more uniform gel coating and less waste. Examples of worksheets with sketches of boat shapes are shown in Figures 6-1, 6-2, and 6-3. These worksheets indicate how a boat builder might divide the components of a boat into areas. In practice it does not matter what the product is, but the surface being sprayed should have two or more defined areas to serve as guides. Once the areas are established, the person spraying the gel coat will mark these as spray zones and note the pump strokes needed to properly coat each zone. Then, as the mold is being sprayed the operator counts the pump stokes -- pacing the spray application to use all the allotted pump strokes in the zone. Since most companies have a wide variety of molds, an appropriate worksheet should be developed for each one so the guides are available whenever that mold is being gel coated. Carolina Classic, a manufacturer of bathtubs and related fixtures, has taken this approach and simplified it through the use of a programmable logic controller (PLC). The PLC is an industrial computer which can be programmed to control a sequence of events in an industrial process. At Carolina Classic they created several short programs that contain the spray time it takes for each model of tub or fixture and loaded the programs into a PLC. In this application the company is controlling the amount of glass chop and resin being applied to the mold. When an operator is ready to spray chop onto the mold, he or she presses the button on the PLC for the appropriate model and begins spraying. Just as soon as the trigger on the gun is depressed, the PLC counts time. When the trigger is released, counting stops. At the instant the spray time is 3/4 elapsed, a horn sounds and the operator continues to complete the mold. After all the time has elapsed, the horn sounds continuously. The operator can spray even when the horn is on, but the horn is intended to pace the work and give the operator and those working in the area confirmation that the amount of material being applied is in control. A schematic of the PLC system is shown in Figure 6-4. Control of Materials -- Material consistency is also an integral part of process control. For a laminator the most critical materials are the gel coat and resin. The complex chemistry that takes place in a laminate is determined largely by these materials. Consequently, if the process is to be controlled, the laminator must kno\v beforehand if the materials to be used are going to perform as Chapter VI Page 97

108 expected. Therefore, a performance test of the materials should be done on receipt of materials and periodically over time if the resin batch is not used up in two weeks. The importance of this type of testing became clear to the authors when the owner of a small boat building company related an experience he had. His company purchases resin by the barrel and usually only two barrels at a time. On receipt of an order of resin he samples the resin and performs some simple tests which include time to gel. On one particular order he found the resin did not gel. After rechecking his results, he called the resin supplier and explained the problem. The resin supplier got back to him later and reported that his test results were correct -- the resin he received was shipped mistakenly without any promoter. The resin supplier also volunteered, that the same batch consisting of hundreds of barrels, had been shipped to another builder who was using the resin unaware of the problem. Programmable Logic Controller Control Panel button for each mold unit loads preset program PLC is connected to resin application system and operator control selects control button for the established program for the mold being laminated. PLC loads the program and monitors quantity of resin applied and/or time required to complete operation..plc can provide operator with immediate feedback as well as record as well as record and download data for analysis. FIGURE 6-4. A schematic of a PLC control system for gel coat application. Chapter VI Page 98

109 A company s size does not determine its level of sophistication nor its ability to control its manufacturing processes. Small companies can adopt elements process control as easily as large corporations. The incoming tests for resins do not have to be time consuming or expensive. The value of these tests will show up in two ways. First the tests establish a history of performance for each supplier. Next, they provide confirmation to you that the material behaves as expected. When problems do occur, you will be able to quickly rule out those factors which you know are correct. This helps to quickly identify the source of the problem. An example of the basic information and tests needed to begin a material control program for resin is shown in Figure 6-4. For companies wishing to move beyond this basic level, there are several sophisticated approaches that can be adopted. Specific tests and recommendations can generally be obtained from your material supplier. Also, companies looking for a more general and comprehensive approach to manufacturing control should look at the guidelines for the North Carolina Quality Leadership Award. Information about this award can be found in Appendix D. Material Record Purchase Order. # Date Rec d -/-/- Supplier Name Lot Number Product Designation Amount Catalyst indicator -yes -no Comments: lncominn Tests I Value I comment Item Gel Time Peak Exotherm I I Time to Peak I I Temperature Humiditv I Approved by:- FIGURE 6-4 Resin material record and incoming tests. Plant Layout -- Localizing And Isolating Problem Operations Plant layout is an art and science. The art requires skill and creativity to blend financial resources, technology, existing structures, and a sense of future needs into an efficient productive factory. Science prescribes the application of technology to create the product. A well run plant is going to properly use technology consistently to be a profitable factory. Unfortunately many plants start-up without the benefits of good art or science. Some plants begin well but over time slip into becoming a workshop. A workshop is a general purpose area that is not well suited for any particular technology or product. A factory however is an organized facility that is able to efficiently replicate one or several products profitably. A profitable factory is able to control waste and Chapter VI Page 99

110 systematically reduce waste over time. In the preceding chapters several technologies for producing composites were discussed. In the following sections in this chapter the discussion changes to the arrangement and housing of production equipment in a factory for open molding. Pollution Sources -- Use of spray guns for applying resin to a laminate is common practice for most open mold fabricators of fiberglass products. Gun-type resin application systems use either compressed air or high fluid pressures or combinations of both to atomize resin materials for efficient delivery to the work surface. As discussed in Chapter 4, HVLP spray systems are considered to be highly effective in delivering resins to the work surface. Gel coat and other resins can easily be transferred in the quantities needed to maintain high levels of productivity. Even the most effective spray systems produce some overspray and styrene vapors while older conventional guns can produce large amounts of overspray making surrounding areas unfit for any other activity. Factors other than spraying also contribute to pollutants entering the workplace. Even if resins are applied by processes not requiring spraying, the very nature of their chemical curing process will still produce considerable vapor and odor. There are always other environmental and physical dangers such as chemical spills involving resins, catalysts, or solvents. Because of the nature of these chemicals, there is always considerable risk of fire and explosion. Pollution in the form of airborne dust particles is also a potential problem since most products require post-molding grinding and finishing operations. In the course of preparing the original manual and this revision more than forty visits were made to plants where open molding accounted for a sizable part of production activities. All of these processors expressed concern about maintaining a safe plant environment and minimizing pollution. Many had undertaken effective measures for implementing pollution reduction strategies. Some approaches to reduction involved innovative changes in plant layout and/or major mechanical systems. Just as with some of the production-based approaches to pollution reduction, a number of the facility-based pollution reduction strategies involved relatively simple measures with extremely high payback potential. Other approaches involved equipment outlays and facility developments with very high capital outlays which would be difficult to recover through increased productivity. Isolating Problem Areas Many firms are producing open molded products in physical facilities that are poorly designed for the production techniques used. Fabricators often perform spray-up in large open structures. This approach normally results in contamination of air throughout the entire facility and necessitates rapid turnover of plant air in order to reduce airborne vapors and solids. Because of this turnover, expenses involved in heating make-up air are increased significantly. When incompatible activities are carried out in these open facilities, there is also considerable potential for cross contamination, such as dust in gel coat finishes or airborne trash falling in the lay-up. Figure 6-5 Chapter VI Page 100

111 provides a diagram depicting typical facility problems. A number of benefits can be derived from segregating or isolating some production operations. Confining Gel Coat Applications Confining spray application of gel coats is not an uncommon practice in the industry. Gel coats carry a relatively high filler content and require high pressures for atomization. Because of these pressures, considerable air contamination occurs in the form of overspray and bounce-back. In comparison to other steps in the fabrication process, gel coating is normally considered to be one of the greatest producers of airborne pollutants. Some high volume fabricators, such as bathtub producers, have successfully utilized moving assembly lines to move molds in and out of enclosed spray booths for gel coating and other spray operations. Other fabricators, such as builders of small and medium sized boats (up to 45 ), have constructed large spray booths for use in gel coating. These builders use mobile mold fixtures and/or overhead lift systems to move molds in and out of the spray area. With a relatively confined working area for gel coat applications, a number of pollution, safety, and housekeeping problems become easier to manage. In a confined gel coat area measures to insure worker safety are simplified. Since these units are isolated from other parts of the facility and can be equipped with separate climate control and ventilation systems, only the workers directly involved in the application process need risk exposure to atomized vapors and solids. Potentially explosive vapors are also prevented from entering the plant. Exhaust and make-up air are easily directed to a particular area, thus avoiding unnecessary and inefficient turnover of air throughout the plant. With this approach only the workers in the gel coat room need wear appropriate safety clothing, eye protection, and breathing apparatuses. Providing cherry pickers to move the operator close to the spraying surface on large molds reduces the spray distance which can substantially decrease styrene loss. Localizing the gel coat application also means that appropriate filtering systems can be placed in the exhaust system in order to reduce the output of airborne pollutants. Where regulations, company policy, or nuisance odor problems create pressures on the fabricators, confining gel coat applications should merit considerable attention. High pollution outputs associated with gel coat application increases the payback potential for filtration or other treatment processes, especially if the spray output can be isolated and confined. Plant maintenance operations and housekeeping can benefit from confining gel coat application to isolated booths or bays. Where application is carried out in the open plant environment, some undesirable output of resins in the form of heavy vapors and solids results. This contamination can affect air throughout the facility creating nuisance odors and a potential for respiratory problems. An increase in the risk of fire can develop because heating, air conditioning, and air handling systems throughout the plant will become coated with a build-up of flammable solids. Walls and floors throughout the area also become coated with Chapter 1 1 Page 101

112 air inlet 1 deck and small part lamination area hull lamination area

113 this build-up. Efforts required to keep equipment and fixtures clean also increase in plants where gel coating applications are not confined. A well designed gel coat application area keeps these contaminants out of the other plant areas. Such units can be easily equipped with disposable wall and floor coverings, filters to protect ventilation systems, and other features which help insure safety and simplify housekeeping chores. Other benefits gained from isolation of gel coating activities include a number of quality related factors. An isolated spray-up area will not be contaminated by other operations in the plant. Mold surfaces and the resulting product finishes are less likely to be damaged by dust or particles from grinding operations or by fibers and resins from nearby lay-up. The climate in a closed area can be regulated in terms of temperature and humidity in order to insure a proper and consistent chemical cure of resins. Special lighting can also be provided to improve visibility and eliminate shadows that might cause improper application. As long as the mold remains in the spray area, there will be no nearby operations to damage or contaminate the coating before it cures. Approaches to Gel Coat Isolation Although use of specialized booths or bays for gel coat application is not a new approach, there has been a recent increase in the number and types of operations electing to use this type of facility. Use of spray booths for gel coating is most common with the producers of relatively small items or high volume producers who have incorporated moving assembly lines into their processing operations. A number of firms have elected to use readily available production type spray painting booths. This approach appears to work well when relatively small molds are used. Small mold fixtures are usually moved in and out of the booth by hand. Where high production is necessary, labor requirements can be reduced by using fixtures such an overhead chain conveyors or track systems to move relatively large units like hot tubs or shower enclosures. The. Lasco Bath Fixtures Division of Phillips Industries in South Boston, Virginia, designed their new plant to make use of an overhead chain system to move conventional fiberglass tub molds through various production areas. These production areas include self contained gel coat and spray-up areas, heated curing booths, demolding, and finishing. The system allows Lasco to minimize labor used in materials handling while allowing for easy isolation of areas which generate most airborne pollution. Carolina Classic in Wilson, North Carolina has several gel coat spray booths in a separate room devoted to gel coat spraying and mold preparation. Each spray booth is fitted with fixtures which allow the operator to rotate and position the mold within the booth for ease of spraying. Using spray booths has improved productivity and helped eliminate nuisance odors in other areas of the production facility. Builders of larger products such as boats, custom engineering fixtures, and automotive body structures have been slower in installing self-contained gel coat Chapter VI Page 103

114 facilities. Even with relatively small boats in the 18 to 25 foot range, moving a mold in and out of various production areas is difficult. The task is more difficult when mold lengths approach 40 feet or more. It becomes nearly impossible with mold lengths of 50 feet or more. With most of these.producers output per mold rarely exceeds one unit a day. This low output means that potential for developing highly mechanized assembly line strategies is limited. Fountain Powerboats in Washington, North Carolina, has installed a large gel coat spray booth in its recently expanded production facility. The company manufactures high performance offshore speedboats up to 12 meters in length. The new spray booth is completely self-contained and is completely equipped with explosion proof electrical systems and an elaborate lighting system. Molds up to 50 feet in length are mounted on special fixtures which allow them to be rolled to various locations in the facility. These fixtures are designed so that the molds may be rolled from side to side to permit easy worker access for spraying and lay-up. Fountain elected to build and use an isolated booth for a number of reasons - gel coat quality, safety, and plant air quality were major factors in the c decision. Since the boats produced are very specialized high performance craft with prices that may enter the six figure range, exterior finish quality is extremely critical for customer satisfaction. The company feels that the quality of the gel coat finish can be more consistently maintained by using a spray booth rather than by spraying in the open plant environment. Trash and other contaminants are practically eliminated. High intensity lighting, required to insure that the operator can deliver a consistent coating, is easier to provide in the booth. Overspray and fogging are reduced since a high volume of air turnover can be easily maintained in the spray booth. The temperature and humidity in the booth can also be maintained at levels which promote proper curing of the gel coat resins. There seems to be little doubt that the use of an enclosed and environmentally isolated area for gel coating can result in a number of benefits. A highly efficient exhaust and make-up air system can be used to remove contaminated air from the spray area. Odors, vapors, and solids are prevented from contaminating other parts of the facility. Where emission outputs are high enough to require filtration or purification, the treatment systems will be much less expensive and more efficient if they are not required to filter air from the entire facility. Overall requirements for plant ventilation and make-up air will also be greatly reduced. Overall plant safety can be improved and potential fire hazards reduced. Approaches to Isolating Other Operations Use of conventional spray guns for resin results in contamination similar to that produced in gel coat application. Not only do these spray-up systems deliver large volumes of resin, but they may also be equipped with glass choppers to chop fiberglass roving into short lengths and spray it onto the molding surface. Some alternative production approaches and equipment are discussed in Chapter 4. Many of these alternative approaches have the potential to nearly Chapter VI Page 104

115 _.. --e--e_ - eliminate pollution output generated during lay-up. Although some of these alternatives are very attractive and will be used by many companies, spray applicators will continue to remain popular. This is true because of their versatility, high efficiency, and relatively low cost. The use of these application systems is not likely to be discontinued in the near future. Where spraying remains the application technology of choice, efforts should be made to reduce pollution associated with the process. The production line approaches used by Lasco Bath Fixtures Division help eliminate contaminants in the lay-up process as well as gel coating. Carolina Classic is using spray booths for both gel coating and lay-up and both areas are separated from other parts of the plant. As with gel coat application, when filtering or treating contaminated air, the task is simplified if the sources of pollution can be isolated. Isolation of the lay-up area can be nearly as beneficial as isolation of gel coating operations. Many of the same pollution, contamination, quality assurance, and maintenance benefits are attained through isolation. Filtering Contaminated Air Air Filtration and Recirculation Systems Selective filtration of plant air should be given serious consideration by any fiberglass fabricator who seriously wants to reduce pollution output. Heavy vapors and solids can be removed from the plant exhaust flow. Even simple paper or fiberglass filters have some effect on the levels of nuisance odors entering the outside environment. Overspray build-up on plant air handling equipment is reduced along with the build-up of overspray on nearby structures, equipment, cars, vegetation, and the ground. These external deposits often make fiberglass facilities appear to be excessively dirty and high in pollution output. Even when a facility is equipped with simple, through-the-wall exhaust fan systems, filter units can be fabricated and installed. Filtering air as it leaves the work area has benefits other than reducing certain emissions. Plant air handling equipment used for exhaust and heating can perform more efficiently when contaminants are removed from the air. Overspray from spray applications and dust from grinding operations can buildup inside ductwork, fan units, motors, and other components. This build-up becomes a potential fire hazard when electricity or heat are involved. Fans and ductwork do not function efficiently when build-up occurs. Excessive build-up reduces air flow and places excessive loads on motors and control systems. This extra load combined with build up on fan motor cooling vents, frequently leads to overheating and burnout of the motor. Some firms are left with little choice about filtering plant exhaust. For a few high output facilities, emission clean-up is mandated by regulatory agencies. Where regulations are severe, elaborate filtration and purification systems are required. For most operations dry filtration can be used to maintain local appearance, protect ventilation equipment, and remove solids in the form of Chapter VI Page 105

116 dust or overspray. In some cases dry filtration has been used to remove enough solid contamination to allow the air to be recirculated. Dry Filtration and Recirculation Many fiberglass fabricators use a dry filtration medium in the plant exhaust system. Protection of expensive air handling equipment is normally sufficient reason to justify expenses for purchasing and changing filters. Dry filters are even used to protect ductwork and fans in facilities which are equipped with elaborate purification systems. Simple dry filter systems can be installed over almost any air intake opening. A number of units, observed in the course of preparing this manual, are simple shop built units constructed of angle iron and/or sheet metal. Large units can also be built in as an integral part of the physical facility. Work Bav, I I false wall I \ \ / *\/\/ \\,, \ \ f \, / \/ I FIGURE 6-6. Work bay air collector. The air collectors are designed as an integral part of the work bays used for fiberglass production activities. Collectors consist of a false masonry wall built Chapter VI Page 106

117 across the rear of the bay. The false wall is placed approximately 18 inches in front of the actual back wall. This wall extends across the width of the bay and from ceiling to floor. An opening extending nearly the full width of the wall is framed up to accept two layers of dry filter material (a cross section of the air collection is pictured in Figure 6-6). Air is pulled through the filter units by an exhaust fan unit located on the mezzanine above the bay. Each bay has its own duct system and fan. Ductwork is provided to exhaust air through the plant roof. An alternate duct provides an outlet for returning air to the plant. A damper system in the ductwork can be regulated to allow all air to be dumped outside the plant or to allow all or part of the air to be returned to the plant environment. The design allows the operator to exhaust all air from a bay when spraying operations are in progress and to return all or part of the air to the plant when pollution output is low. Plants that have used this system indicate that the units have proven to be efficient in sweeping contaminated air from the workplace. On occasion an operator will forget to switch to outside air discharge when spraying operations are in progress. Odors are immediately noted by workers on the mezzanine, and word is passed to the operator. Using this system to filter and recirculate air from grinding bays has not been successful. The dust created by grinding proved to be difficult to remove using single stage filtering. Supplemental filters on the discharge side of these units should be installed. Case Study No 14 Type: Company: Location: Contact: Phone: Purpose: Motivation: Equipment Supplier: Payback Period: Plant Air Recirculation System S2 Yachts, Inc. / Tiara Yachts 725 East 40th Street Holland, MI Leon Slikkers (616) Filter air exhausted from plant environment Recirculate plant air Reduce requirements for make-up air and heating Improvement of air quality in plant Reduction in utility costs Building contractor for new facility Not available Chapter VI Page 107

118 Case Study No 14 Continued Comments: Source: All pollution intensive operations are confined to separate work bays. Each bay is equipped with an exhaust and filtration system which allows air to be recirculated or discharged. Plant visit in March, 1987 and phone conversations with company president (December, 1986) Wet Filtration Systems Water wash spray booths have been successfully used to control emissions associated with spray application of industrial finishes. Manufacturers of spray application equipment frequently market conventional and water wash spray booths. The typical unit features a powerful exhaust system which pulls contaminated air through a mist or spray of water. Most filtration units are designed to provide a water wash by using pumps to spray water in the air passageway. Pumpless designs are also available. Figure 6-7 features cross sections of two water wash spray booths. Special chemicals can be added to the water reservoir for the purpose of trapping contaminants. Chemicals added to the water can make contaminants settle to the bottom of a collection tank or float on the surface for collection. Waterfall units appear to offer some advantages over conventional dry filtration units. Dry filters clog quickly during heavy spray-up and gel coat application. This clogging lowers the surface velocity of air sweeping the work area and replacement of filters drives up maintenance costs. The air passages on waterfall units do not clog, and filtration capacity remains high unless water in the reservoir becomes overloaded with solids. Potential fire hazards are also reduced by the water wash system. Most local codes accept water wash spray booths as the best type of spray booth available. Units can be designed to fit the requirements of almost any production facility. Although use of these units for paint spray operations is widespread, there is little evidence of applications in open molded plastics facilities. Hatteras Yachts in New Bern, North Carolina has successfully used water wash booths in two of their production areas. A spray painting area approximately 150 feet long, 40 feet high, and 40 feet wide is equipped with pumpless water wash exhaust units along the full length of each side wall. The units exhaust through the roof and make-up air is forced in from overhead. Make-up air and exhaust air are carefully matched in order to maintain a slightly positive air pressure. These water wash units have enabled the company to efficiently reduce emissions associated with the spray application of large quantities of urethane Chapter VI Page 108

119 outlet to stack clean air entrainment plate contaminated Water Wash System with Pump Supplied Spray Pumpless Water Wash System FIGURE 6-7. Water wash spray booths. paints. A smaller area of the main plant is also equipped with a water wash booth. This booth is used to filter dust from grinding and finishing operations carried out on small fiberglass parts. The original water wash units worked so well that Hatteras elected to incorporate water wash filtration units in a new production that was added to the New Bern plant. The new facility was completed during the summer of 1987 and was designed to accommodate production of yachts considerably larger than 75 feet. The building will house three large lay-up areas which will have all exhaust air filtered through pump type water wash exhaust units Chapter VI Page 109

120 c Fume Incineration, Burning Styrene Emissions High heat can be used to eliminate fumes and odors associated with styrene and other polymers. In situations where emissions associated with open molding processes are particularly high or severely restricted by regulation, incineration may prove to be a viable option. Incineration of styrene requires temperatures approaching 1,400 F. These high temperatures mean that any system developed for incineration of styrene must be carefully engineered to insure safety, a reasonable working life, and efficient use of energy. Chapter 3 discusses the regulatory aspects of incineration and the design considerations for stack height. Designs which provide only a gas fired heat chamber are relatively inexpensive to design and construct. Such designs, however, will require excessive use of fuel to heat all exhaust air in a relative short period of time. Common afterburner units are designed to rapidly ignite and oxidize the volatile organic compounds (VW) found in fumes. Efficiency of these units can be improved by adding a tube type catalytic converter to hold the VOC s at a high temperature for a longer period of time. Another design concept features a number of ceramic filled recovery chambers connected to a central bum chamber, the plant exhaust duct, and a discharge stack. These connections are made through a complex manifold system which is connected to a modern computerized monitoring and control system. A simple diagram of a unit depicting the interaction of two recovery chambers with the burn chamber is shown in Figure 6-8. Each recovery chamber can alternate between being in the inlet or outlet mode. Exhaust enters from work area. ceramic filler to exhaust stack. ceramic filler tn Pyhallct FIGURE 6-8. Fume incineration unit. When a chamber is in inlet mode, plant exhaust is fed over the heated ceramic material in the chamber and out into the burn chamber. As the VOC s leave the Chapter VI Page 110

121 chamber, their temperatures are very close to the incineration temperature. Oxidation is completed in the central chamber. The bum chamber is equipped with a burner system in order to maintain a predetermined temperature. Some ignition of the volatiles will occur while they are passing through the ceramic materials in the recovery chamber. When the content of volatiles is high, this auto ignition may provide all of the heat required for recovery, and the burner system will go to the pilot mode. Purified air is passed from the bum chamber through the ceramic bed in a chamber which is in the outlet mode. Heat from this air is absorbed by the ceramic material. As heat is withdrawn, the cooled air exits to an exhaust fan and discharge stack. Most units consist of a central bum chamber and up to seven recovery chambers. Once sufficient exhaust is passed through an outlet chamber, the ceramic bed becomes hot enough to allow the chamber to switch roles and become an inlet chamber. The units have to be brought up to temperature before the plant exhaust system can be placed in use. Incineration Unit Application -- The Lasco Bath Fixtures Division of Phillips Industries has installed a 20,000 SCFM incineration unit in its bathtub production facility located in South Boston, Virginia. Because of the high volume of resin use anticipated for the operation, installation of a treatment system was required by the State of Virginia. In an effort to attract Lasco to the South Boston location, some local funding was used to assist in the purchase of a treatment unit. The company selected a Re-ThermTM model 20 produced by Regenerative Environmental Equipment Company (see Appendix C). The unit cost was approximately $750,000. All exhaust from the isolated gel coat and spray-up areas are exhausted to the Re-Therm unit. Performance of the unit is electronically monitored and controlled by a system of sensors and a computer unit. A permanent record of the unit s operation is automatically entered on a paper time chart. All plant equipment is tied to uninterrupted operation of the unit. If the unit is not operational, all spray and resin application systems are automatically shut down. In the event of a system failure, the appropriate state agency must be notified, and all performance charts must be kept on file for review by state inspectors. In two years of operation only one minor failure has occurred. This failure was traced to lightning damage of fuses and electronic components in the control system. The only other maintenance required has been a topping off of the ceramic beds. Lasco also adds another treatment to air discharged from the plant. An odor masking chemical is misted into the plant discharge vents and stacks. This chemical has a sweet pleasant odor that helps mask the smell of styrene. During the first few months of operation some complaints were received about the smell of the masking chemical. This problem was eliminated by reducing the quantity of masking chemical released. The company has been pleased with the performance of its incineration unit. Maintenance costs have been low and pollution output is dramatically reduced. Chapter VI Page 11 1

122 There have been few interruptions to production. Neighbor complaints about odor and pollution from this new facility have been minimal. Fuel costs have been estimated to be less than $5.00 per hour. Since location incentives were provided and the unit was deemed essential for plant operation, payback calculations were not available. Case Study No 15 Type: Company: Location:. Contact: Phone: Purpose: Motivation: Equipment Supplier: Payback Period: Comments: Source: Incineration system for styrene emissions Re-ThermTM model 20 Lasco Bath Fixtures l? 0. Box 1177 South Boston, VA John Davenport, Production Manager (804) Remove styrene emissions from plant exhaust Meet Virginia regulations Required by State for operating plant Improvement of air quality Lower utility costs when compared to other units Regenerative Environmental Equipment Co., Inc. Box Speedwell Avenue Morris Plains, NJ Not available All pollution intensive operations are confined to isolated work booths. Exhaust from booth is fed directly to incinerator. Plant visit in April, 1987 and phone conversations with plant manager and equipment supplier(march, 1987). Chapter VI Page 1 12

123 \.....,_. _ ) _. :.:.y.. _ > :;f. ; -.., - -- :*!&a,.;,-, *....I. _ _.- _i _Ab_Y-,A~i.;;--~ - -*w_ - - Y w _LyI Controlling Air-Flow and Exhaust There are many codes and standards that govern the ventilation of commercial and industrial buildings. These may be expressed in terms of* natural ventilation, such as the area of window space in a facility as a percentage of its floor area, or in terms of mechanical ventilation, such as the number of cubic feet per minute (CFM) of air required per occupant or unit of space. These standards establish good ventilation practice which is termed dilution ventilation. However if human or environmental safety is threatened by highly toxic substances, the guidelines governing acceptable levels of airborne contaminants are embodied in exacting and comprehensive state and federal regulations. The ventilation of these contaminants may thus require special equipment along with administrative and technical measures to achieve compliance. Most industrial and commercial requirements for ventilation fall somewhere between these two extremes. That is, the waste by-product or contaminant is being generated at a rate that is acceptable for immediate exposure, but presents a danger in higher concentrations that cannot be dealt with adequately through good dilution ventilation. Dilution ventilation can be successfully used to control vapors from some organic liquids, such as the less toxic solvents. In general, it is not successful for the control of dusts, fumes, gases, mists and vapors that can produce an unsafe, unhealthy, or undesirable atmosphere. The control of these substances requires a system of exhaust ventilation designed with the basic principles of airflow in mind. Exhaust Ventilation The most fundamental principle of airflow is that the flow of air between two points is due to the occurrence of a pressure difference between the two points, with the air flowing from the area of high pressure to the area of low pressure. Simply stated, as an exhaust fan evacuates air from its intake side, it creates and area of low, or negative pressure, causing air to move from all directions toward the area under suction. Maintaining Positive Pressure Before listing some of the specific guidelines for achieving exhaust control, it should be noted that a complete industrial ventilation system should provide a supply of fresh air to compensate for the air being exhausted from the building. If enough new air is not supplied, the pressure of the building will be negative relative to the surrounding atmospheric pressure. This negative pressure results in the infiltration of air through open doors, windows, cracks, combustion equipment vents, etc. It also increases the total system resistance, making exhaust fans consume more energy than is necessary in a balanced system. There are other potential problems. As little as 0.05 inches (water gauge) of negative pressure can cause workers to complain about drafts and might cause down Chapter VI Pagp 113

124 drafting of combustion vents, creating a potential health hazard. If workers near the plant perimeter complain about cold drafts, unit heaters are often installed. Heat from these units is usually drawn into the center of the plant because of the velocity of the infiltration air. This leads to overheating in the area and further complaints. It is therefore recommended that a slight positive pressure be maintained in the facility through the use of sufficient intake fans or air conditioning/heating systems. General Guidelines -- The propose of exhaust ventilation is to entrain the airborne contaminant or nuisance in the air flow lines created by the system. It is frequently and mistakenly assumed that, because of the specific gravity of a contaminant, it is either heavier-than-air or lighter-than-air and will eventually rise or fall of its own accord. Actually, even relatively heavy dusts,. fumes, vapors, and gases are truly air-borne and are not subject to any appreciable migration up or down because of their own weight. This is because the contaminant-air mixture is usually overwhelmingly composed of air. The behavior of this mixture is thus virtually the same as for clean air and should be considered as such when planning an exhaust system. No two facilities or production processes will be alike, but the following guidelines cover the major points to consider in achieving effective exhaust ventilation: 0 Exhaust fans or outlets should be located at or below the operator work level. They will then tend to pull the contaminant down and away from breathing level. 0 The contaminant-producing process or equipment should be located between the operator and the exhaust outlet. This will pull the contaminant away from the operator area. 0 Exhaust outlets should be placed as close as possible to the source of contamination. Obviously, the closer the outlet, the more rapidly the contaminant can be entrained and exhausted before it disperses into the room. a Consider using a push-pull system in which the contaminant is directed toward the exhaust outlet(s) by a low velocity airstream produced by fans or ducted inlets on the other side of the operation. It is important to keep velocity low to avoid creating eddies and turbulence that would disperse the contaminant. 0 Avoid cross-contamination of clean work spaces by arranging the facility so that HVAC inlets, cooling fans, or other exhaust vents do not produce cross-currents of air at the source of contamination. Note: ASHRAE HANDBOOK, 1984 SYSTEMS, p. 20 Chapter VI Page 114

125 0 Partitions, lowered ceilings, etc. can be used to advantage to enclose the contaminating process as much as possible. The more complete the enclosure, the more efficiently the exhaust system will evacuate the contaminant. 0 If cost allows, consider the use of an exhaust hood. (See Local Exhaust below). 0 Exterior exhaust outlets should be kept well away from open inlets to the building. Ideally, an exhaust stack above roof level is used. Alternatively, outlets should be placed to take advantage of local prevailing winds and the aerodynamics of the building to avoid re-entry. An additional recommendation would be to design the provisions for exhaust ventilation with potential future regulatory changes in mind. In terms of environmental safety, the trend is toward ever-greater control of hazardous substances. If possible, the owner should research any governmental initiatives in that direction. The facility might then be designed for compatibility with the types of containment equipment likely to be used. This is usually less expensive than retrofitting the facility into compliance. Local Exhaust For certain applications, the most effective method of evacuating a hazardous airborne substance from the workplace is to utilize a truly localized exhaust system. This consists of a ducted hood and an exhaust fan or other air-moving device. It offers optimum contamination control with minimum air volume requirements and therefore lowers the cost of cleaning the air. Hoods are either enclosing or non-enclosing tvnes. The enclosing type is obviously more effective and more efficient, but it is not always practical because of the access requirements of the process or machinery. The non-enclosing type can be nearly as effective when placed in very close proximity to the process. This too can be impractical in terms of access to the process or machinery. Inasmuch as localized exhaust is the most cost-effective method of removing contaminants, it is in the owner s interest to investigate its use wherever possible. The proper design and construction of a hood requires thorough knowledge of the principles of airflow and of the specific application to which it is dedicated and may require the services of an HVAC engineer. Chapter VI Page 115

126 Chapter VI Page 116

127 APPENDIX A The changes made by Arjay initially looked as if the company was going to increase costs instead of improving profitability. Their initial efforts caused the comnanv to I, pay on a per unit basis: * A Case Study in Waste Reduction and Profitability Ajay Technologies in Large, Florida, was a well established contract producer of laminates that sold component parts to manufacturers in the boating industry. Currently the company is focusing on offering its expertise and lamination technology to others in the industry. However, before this change in emphasis occurred, Arjay made full use of the technologies and methods it s now helping other companies put to use. The experience and success Ax-jay achieved began during the early nineties when the company made several significant changes in its manufacturing methods and techniques to reduce waste and to improve profitability. Because of Arjay s total focus on fiber reinforced plastics (FRP), the company is a true cost center for lamination. Arjay s experience indicates that the typical laminator, one that uses gel coat and sprays resin, can cut its costs by as much as 24%. This can be done says Bob Cottrell, the President of Arjay Technologies by rethinking what s fast, what s expensive, and what s clean. The work his company did he believes will make a company more productive and competitive. 10% more per pound for gel coat; 40% more per pound for fiberglass, 7% more per pound for resin; 28% increase in the time required rollers; largely due to changing to knitted fabrics; to laminate since they started using resin 37% higher labor rate than when they started because they cut back their work force. Specifically they let the least experienced people go, thereby raising the average plant wage rate. When a company is trying to break a manufacturing paradigm and implement change then many of the present performance indicators may show that the changes are making things worse. Consequently it would appear that a marginally profitable operation may become unprofitable. The reason this can occur is that most that are on a unit of measure basis and the changes instituted resulted in the basis. manufacturing systems have cost indicators not on a cost per product measure. At Arjay following improvements on a per product This case study is based on a presentation by Robert L. Cottrell to the Composite Fabricators Association, Fabrication 93, Nashville, Tennessee, October 28, 1993 Appendix A Page 117

128 * Gel coat was reduced by 50% -- Gel coat usage was cut in half by spraying at 9-11 mils as opposed to Resin was reduced by 54% - Resin was reduced by over half by achieving higher glass ratios and wasting less resin. Was@ was reduced by 90% - This resulted from reduced materials usage, instituting good material handling practices, and eliminating wasteful manufacturing methods and techniques. Work force was reduced by 30% --The manufacturing methods allowed Arjay to reduce its manufacturing work force by 30% while it turned out the same quantity of work Total cost of production dropped by 24% -- This was the net result from all the changes put into effect. Cottrell says the focus for change was waste minimization. He points out that I- we tried to get rid of that trash collector. At least waste minimization was what we thought we were doing when we started our journey. As we look back today, we see that it was far more than that. When I read the current best selling book, Reengineering the Corporation by Michael Hammer and James Champy, it occurred to me that what we inadvertently had done was reengineer the FRP operation. Prior to the change Arjay s typical practice for hand lay-up involved a spray wet out operation using 1 - l/2 ounce mat. After the change they used 3/4 ounce mat and knitted fabric. The resin application equipment changed too. They replaced the spray guns with roller applicators. The changeover to rollers began on the simpler shaped hulls, then moved on to include complex decks and liners. The change in resin formulation, application equipment, and glass resulted in a reengineered lamination operation. Production Characteristics Before Reengineering * Resin Application - Spray Gun * Gel Coat Thickness MILS * Glass to Resin Ratio - 26% * Solvent Type Used - Volatile, Acetone * Lamination Room Environment - Dirty, High Maintenance Spraying resin, applying thick a gel coat, employing glass ratios below 30%, using acetone, and operating in a dirty, high maintenance environment creates a production system that places a manufacturer in a financial grid or paradigm that limits the profit that can be realized from a business. This type of manufacturing system existed for about ten years at Ajay before the change and yielded material, labor and operating expenses that varied only slightly. A typical profit and loss statement for that period can be characterized as follows. Appendix A Page 118

129 Characteristic Profit and Loss Statement for the Old Manufacturing System Sales $100 Material 38 Labor 18 Operating Expense 8 Prime Profit $36 As you can see, for every $100 of sales, material costs were 38%, labor costs, including workman s compensation insurance, medical, vacations, holidays, etc., were 18%. Opera tr n g costs, including utilities, solvents, supplies, maintenance items, etc., were about 8%, leaving a Prime Profit of 36%. Fixed costs which would be subtracted from prime profit to calculate gross profit are not shown. As a contract producer selling component parts to assemblers and marketers, Ajay is a true cost center for lamination. There are no assembly costs or other post FRP part costs to cloud the analysis. Consequently, this analysis is useful for providing a means for evaluating the financial impact these changes will have on a company. Since the major changes were in the materials, the biggest expense category, its useful to examine where the money goes. Material Gel Purchased Part Weight Lbs. Lbs. $/Unit Total Cost 5 2 $1.oo $ 5 Glass Resin Total 52 Lbs. 31 Lbs. $38 Examining the left hand column in the table shows that $38 for material purchased 5 pounds of gel coat, 12 pounds of glass, and 35 pounds of resin for a total of 52 pounds to make a part selling for $100. However the second column shows that only 31 pounds (60%) of the 52 pounds purchased actually made it to the part. The other 21 pounds (40%) that was purchased became trim scraps, emission losses, overspray, cutouts, scrap parts, and other forms of waste. Note that the gross or overall glass ratio (excluding the gel coat) is 26% (12 / ), although the finished part had a 31% glass ratio (9 / ). All of these figures came from a material balance study of the lamination operation. This type of analysis is also referred to as a sources and uses study. The purpose for this type of study is to determine what and where the material is used. It is a good first step for defining the manufacturing paradigm. Appendix A Page 119

130 ._. - --_ _ _--- - From this study it is apparent that the resin supplier is the significant vendor in - - terms of dollars. The money sent to resin companies exceeds the amount sent to the glass suppliers by a ratio of 21 to 12. This means that if a tanker of resin costs $21,000 you would spend only $12,000 for the glass to go with it. The gel coat costs are less than one fourth the resin costs. These comparisons provide a means for establishing priorities for changing the system. Now, look at the labor portion of the profit and loss statement. For each $100 dollars of sales at Arjay, there is $18 of labor cost. At Arjay the average hourly wage at the time of the study was $8.00 per hour. This amount includes direct labor such as laminators and gel coaters as well as QC people, warehouse people, maintenance people, and supervision. The average hourly wage for the manufacturing system a can be calculated for a period by dividing the gross payroll by the total hours worked. However, the number that is really needed is the gross wages for the period divided by the total sales during the period. In this P&L the number is actually the wages per each $100 of sales for the period. This provides a ratio to determine what part of each $100 of sales is labor. In this case its $18 per each $100 of sales. It is extremely important to understand that the TOTAL labor represents all people involved in manufacturing since one of the major benefits from reengineering comes from reducing the necessity for staffing the non-value adding positions required by the current manufacturing system. In brief, here is what Arjay Technologies did to change their operation. They started with the resin by changing the chemistry and the way it was stored and dispensed in the plant. The new resin included an extender, had a higher reactivity, and was more viscous due to reduced styrene content. Ax-jay promoted the resin themselves instead of having the supplier do it. They also installed a temperature controlled bulk storage and recirculation system that looped the entire plant. The catalyst, MEKP, was also circulated to each mixing unit in the plant. The result was a resin that gave predictable performance and worked well with the new lay-up methods. Although the changes in the resin were important, there were other factors that contributed to Arjay s waste reduction and improvements in financial performance. The reengineered system included: 0 A gel coat spraying operation that was brought into control through the application of process control techniques. This allowed Arjay to reduce the amount of gel coat sprayed in two ways. First, they were able eliminate the excessive gel coat thickness that resulted from a highly variable process. Second, because of the reduction in variability they were able to move to the lower end of the range of gel coat thickness needed. The use of a low pressure spray system also helped because of improved transfer efficiencies. 0 Resin spraying was eliminated with the introduction of resin roller applicators. These applicators apply resin more uniformly without over spray. Because the resin is not atomized, the applicators significantly reduce styrene loss to the air and maintain a much cleaner work area. Equipment Appendix A Page 120

131 maintenance is reduced because of the change over to a simpler resin roller system. Solvent usage is also reduced and can be further reduced through the use of a closed system to flush and clean the roller equipment. 0 Glass ratios were increased through the use of knitted and specialized glass fabrics. The result was an increase in the gross glass ratio to 38%. The increase in the glass ratio was also due to some laminate engineering and the benefits that can be realized through the application of resin with the roller system. 0 A high boiling point solvent is sparingly used. Acetone was eliminated and not seriously missed because of the cleaner resin application methods implemented. 0 The operation is noticeably cleaner and requires significantly less maintenance. This can be attributed largely to the changes in resin and gel coat application processes. The full impact of the changes to the manufacturing system are apparent by comparing the changes in the materials used to make the original 31 pound part. The total material cost ($38) dropped to $27, a reduction of 29%. The part weight also went down by 16%. This reduction in weight is a the result of changes in both the manufacturing technology and part design. Savings also showed up in labor and operating expense. The labor cost dropped slightly to $17 from $18 and the operating expense was cut in half to $4. Before Material Comparisons After Lbs. Mat 1 $/Lbs. Total Lbs. Mat 1 $/Lbs. Total Weight cost Weight cost Gel $ Glass Resin Total $ $27 40 % of purchased materials wasted 10 % of purchased materials wasted Summarizing These changes in manufacturing resulted in making Arjay s glass vender the major supplier. The dollars going towards the purchase of glass were 40% more than the amount spent with the resin supplier. The gel coat cost as a percentage of glass also went down significantly from 42% to 21%. Comparing costs on a unit of measure basis to the cost per unit of production makes the point again that a total approach Appendix P Page 121

132 IT, -I..-. : I! 1 I k to reengineering the laminate has to be considered to achieve waste and cost reduction.....;;:i.;: * Gel coat * Glass * Resin Cost Per -Pound Costs Per Unit of Production up 10% Down 40% up 40% UP 17% up 7% Down 52% Arjay s approach to waste reduction and performance improvement appears to be successful. The methods and techniques used are straightforward and do not require disproportionate investments in time or money. They do however require a company wide approach that will challenge everyone in the manufacturing system to become involved in rethinking what s waste, what s expensive, and what s profitable. Appendix A Page 122