PREPRODUCTION INITIATIVE - NELP MAGNETIC PARTICLE FLUID PURIFIER FINAL REPORT NAS NORTH ISLAND, CA

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1 1.0 INTRODUCTION PREPRODUCTION INITIATIVE - NELP MAGNETIC PARTICLE FLUID PURIFIER FINAL REPORT NAS NORTH ISLAND, CA The U.S. Navy has adopted a proactive and progressive position toward protecting the environment and complying with environmental laws and regulations. Rather than merely controlling and treating hazardous waste by end-of-the-pipe measures, the Navy has instituted a program for pollution prevention (P2) to reduce or eliminate the volume and toxicity of waste, air emissions, and effluent discharges. P2 allows the Navy to meet or exceed current and future regulatory mandates and to achieve Navy-established goals for reducing hazardous waste generation and toxic chemical usage. P2 measures are implemented in a manner that maintains Navy readiness. Additional benefits include increased operational efficiency, reduced costs, and increased worker safety. The Navy has truly set the standard for the procurement and implementation of P2 equipment. The Chief of Naval Operations (CNO), Environmental Protection, Safety, and Occupational Health Division (N45), established the Pollution Prevention Equipment Program (PPEP), through which both the Naval Air Warfare Center Aircraft Division Lakehurst (NAWCADLKE) and the Naval Facilities Engineering Service Center (NFESC) serve as procurement agents under the direction of N45. P2 equipment is specified and procured under two complementary initiatives the Preproduction Initiative (i.e., technology demonstration) and the Competitive Procurement Initiative. The Preproduction Initiative directly supports both the Navy Environmental Leadership Program (NELP) for P2 shore applications and the P2 Afloat Program, which prototypes and procures P2 equipment specific to the needs of ships. This report provides an analysis of the procurement, installation, and operation of P2 equipment under the Preproduction Initiative. Technology demonstrations and evaluations are primarily performed under NELP at two designated NELP sites Naval Air Station (NAS) North Island and Naval Station (NS) Mayport. Additional sites have been added as required to meet mission goals. The program involves defining requirements, performing site surveys, procuring and installing equipment, training operators, and collecting data during an operational test period. The equipment is assessed for environmental benefits, labor and cost savings, and its ability to interface with site operations.

2 2.0 BACKGROUND 2.1 U.S. Navy Magnetic Particle Inspection U.S. Navy nondestructive inspection (NDI) laboratories perform magnetic particle inspection on aircraft and non-aircraft components/parts to locate surface and nearsurface discontinuities. Magnetic particle inspection consists of three basic operations: establishment of a suitable magnetic field, application of magnetic particles, and examination and evaluation of the particle accumulation. A suitable magnetic field is established by applying an electric current to the ferrous part being inspected. A magnetic particle fluid composed of a petroleum distillate fluid that contains minute, suspended, ferromagnetic fluorescent particles is applied to the surface of the part. The fluorescent particles are drawn to any magnetic leakage field caused by a discontinuity. This magnetically held collection of fluorescent particles can then be visibly observed with a black light, indicating the location, size, and shape of the defect. After a period of time, the magnetic particle fluid degrades and becomes contaminated with oil, grease, dirt, water, etc., and must be replaced. Once it has been determined that the magnetic particle fluid is no longer usable, the used fluid is completely drained from the magnetic particle fluid holding tank, disposed of as a hazardous waste, and replaced with a new batch of petroleum distillate fluid and fluorescent particles. The process of draining, disposing, and replacing the fluid involves draining the fluid from the holding tank into the two original five-gallon containers, labeling the containers, completing used fluid turn-in documents, completing new fluid procurement documents, arranging for the old fluid to be collected by the facility waste department, having new fluid delivered by the hazardous materials department, and refilling the holding tank with new fluid. 2.2 NAS North Island Magnetic Particle Inspection NAS North Island (NASNI) Aircraft Intermediate Maintenance Department (AIMD), 500 Division, conducts NDI using magnetic particle inspections on a variety of aircraft and ship components. All labs are required to change and replenish their fluid every 30 days in accordance with the maintenance requirement card (MRC). The NASNI NDI laboratory typically drains and disposes of approximately ten gallons of magnetic particle fluid as a hazardous waste each month. 2.3 System Selection In view of the Navy s P2 goals, a method was required to extend the service life of the magnetic particle bath oil and to reduce the amount of hazardous waste disposed of and new petroleum distillate fluid procured. A purifier that interfaced with the magnetic particle fluid holding tank was deemed capable of reducing contaminants to acceptable levels, thereby eliminating the need to drain and dispose of used fluid and refill the system with new fluid.

3 NDI lab requirements were considered before a system was selected. The chosen purification system was required to interface with lab utilities, have a small footprint, be chemically compatible with magnetic particle fluid, and be easily/safely maintained and operated. After a vendor evaluation was conducted, the Mayhew Industries, Inc. Model MP-1 portable purification system with M7G1 filter element was selected as the best candidate. 3.0 EQUIPMENT DESCRIPTION The Mayhew MP-1 portable fluid purifier is a compact, self-contained unit designed to flush entire fluid systems while in or out of service and to remove deleterious contaminants. The MP-1 provides magnetic particle fluid purification in a simple, closedloop process that eliminates the need to drain, transport, store, and dispose of spent magnetic particle fluid. The closed-loop system also eliminates direct operator exposure to the magnetic particle fluid, creating a safer/healthier working environment. The MP-1 is completely enclosed in steel housing; mounted on casters for portability; and furnished with all necessary gauges, switches, controls, filters, and a 20-ft. length of electrical cord for connection to the site electrical system. The unit s paint and components are chemically compatible with the magnetic particle fluid. 3.1 System Components Fluid Reconditioner Assembly This assembly protrudes from the top section of the housing and consists essentially of the reconditioner case and one M7G1 replaceabletype filter element. M7G1 Replaceable Element The filter element is composed of virgin wool and cedar chips, which remove particulate, moisture, residue, and acidity from the fluid. Visualator Assembly This connects to the pump inlet line to provide a visual check of fluid condition as it is drawn from the holding tank. A built-in wire mesh screen traps any large particles of foreign material as the fluid flows through the visualator. The screen is removable for cleaning. Pump Assembly The pump is a positive displacement, rotary gear-type unit with an output capacity of approximately 3.5 gallons per minute (gpm). Relief Valve Assembly This valve is a protective device built into the flow control valve to prevent overpressurization of the fluid reconditioner system. Sized to pass the full output of the pump, the valve is factory set at 65 psig. Flow Control Valve Assembly The flow control valve connects to the line at the inlet to the fluid reconditioner assembly and is lever-operated from a control located on the side panel. The valve may be positioned to direct full pump delivery through the fluid reconditioner or to bypass the fluid reconditioner when preheating of the fluid is required. With the valve positioned between the filter and transfer

4 positions, a portion of the pump delivery is directed through the reconditioner and the remainder is bypassed, thereby reducing pressure on the system. Hoses All units are equipped with two hose assemblies. The MP-1 has a six-foot length of 5/8-in. hose. Hose materials are chosen to be compatible with the operating fluid. 3.2 Specifications Dimensions: 36"h x 12"l x 12"w Weight: 96 lb. Motor HP: 1/3 Power: 110V, single phase Pump Flow Rate: 3.5 gpm Hoses: 5/8" x 6' 3.3 Implementation Requirements Because the unit is compact and portable, implementation requirements are minimal. The unit does require a 110-V electrical power supply. 3.4 Treatment Process The unit s inlet and outlet hoses are placed directly into the magnetic particle fluid holding tank. The unit is turned on, and fluid is pumped into a glass visualator assembly that contains a 40-mesh strainer. The visualator allows the operator to observe the condition of the fluid as it enters the unit, and the strainer keeps large particles from entering the pump. A 3.5-gpm pump moves the fluid through the M7G1 filter, which contains a combination of virgin wool and cedar chips that remove particulate, moisture, residue, and acidity from the fluid. The fluid is circulated though the system a number of times until the desired clarity is achieved. In the case of NASNI, filtration time typically ranged from 5 to 25 minutes, depending on the condition of the fluid and filter. After filtration, approximately 1.5 ounces of new fluorescent particles are added to the filtered petroleum distillate, and normal inspections can resume until the bath fluid again degrades. During the evaluation period, the ten gallons of magnetic particle fluid that had previously been disposed of was purified once a month and reused. Only a small amount of makeup fluid was required during this time to replace fluid that had adhered to parts, which were removed after inspection. 3.5 Maintenance Maintenance requires only two tasks: replacing the M7G1 filter element and cleaning the visualator screen. The filter element must be replaced when the unit s pressure gage indicates a pressure drop of 65 psi across the filter, when flow is reduced at the end of the discharge hose, or when the visualator shows no change in fluid clarity (dark to clear). The filter is easily removed from inside the reconditioner case by draining the unit,

5 unthreading one filter hold-down clamp, and lifting out the element. The filter must be discarded as a hazardous waste and replaced with a new filter element. In the case of NASNI, the filter required replacement after eight months, or after filtering approximately 80 gallons of fluid. The visualator mesh strainer should be cleaned when the filter element is replaced. The strainer is easily removed by unscrewing the unit s glass housing, and then unscrewing and removing the strainer. The strainer is rinsed with solvent, dried, and reassembled. 3.6 Benefits Reduces the quantity and cost of hazardous waste disposal. Reduces the requirement for procurement of new fluid. Reduces the amount of labor involved with maintaining magnetic particle fluid. Reduces the amount of downtime caused by maintaining and reordering magnetic particle fluid. Provides a healthier and safer work environment. 4.0 DATA ANALYSIS Data for the magnetic particle fluid purifier system were collected at the NASNI AIMD NDI laboratory, 500 Division, San Diego, CA, from July 1998 to July Quantitative Analysis The collected data were reviewed and analyzed to produce a cost-benefit analysis. The 10-year return on investment was $38,002, with a payback period of 0.63 years. 4.2 Qualitative Analysis Installation Modifications to the NASNI NDI laboratory were not required to install the MP-1. The MP-1 fluid purifier is a portable unit that requires only a plug-in electrical supply of 110 V and a storage space sized 36"h x 12"l x 12"w. Electrical power is supplied to the unit via a 20-foot electrical cord, which can be disconnected and stowed between uses. The unit was delivered to the NASNI NDI lab in July 1998 with a preinstalled filter Training The simplicity of the MP-1 fluid purification unit s operation and maintenance eliminated the need for system training. The operation and maintenance manual includes an explanation of system components and their functions, operation, maintenance, and troubleshooting.

6 4.2.3 Maintainability In view of the design s simplicity, the MP-1 fluid purification unit operated trouble-free during the one-year evaluation period. The unit required only one filter replacement and one visualator screen cleaning. System performance has been consistent and reliable Interface with Site Operations The MP-1 purifier has easily interfaced with NASNI NDI operations. Modifications to the laboratory were not required to accommodate the unit s power supply or storage requirements. In addition, use of the purifier has reduced the amount of time, tasks, disposables, consumables, and risk associated with maintaining the lab s magnetic particle fluid. This has been achieved through a reduction in the number of times the hazardous magnetic particle fluid must be contained, labeled, turned in, reordered, and transported. The hazardous material disposal requirement has been reduced from once a month (used fluid, disposal method) to once every eight months (spent filter, purification method) Overall Performance Overall, NASNI NDI laboratory personnel have found the MP-1 magnetic particle purifier to be an outstanding unit. The MP-1 fluid purification system has provided consistent and reliable performance, is easy to use and maintain, and has operated flawlessly during the evaluation period. Negative feedback was nonexistent during the one-year evaluation period. 5.0 LESSONS LEARNED NDI labs must reserve a small quantity of new magnetic particle fluid to replace fluid that adheres to parts removed from the fluid bath after inspection. 6.0 CONCLUSIONS NASNI AIMD 500 Division site personnel have been very pleased with the performance of the technology in general and this system in particular. The system easily removes contaminants from the fluid and quickly reconditions the magnetic particle inspection system. The unit s compact size, efficiency, and low maintenance requirements have resulted in a significant reduction in the amount of time, tasks, disposables, consumables, and risk associated with maintaining the magnetic particle bath. The results of this evaluation indicate that the MP-1 purification system is an excellent reconditioning technology for any facility that currently disposes of used magnetic particle fluid from NDI equipment.