Preventive Maintenance at Rescue Missions. by Michael Liimatta, Director of Education International Union of Gospel Missions

Transcription

1 Preventive Maintenance at Rescue Missions by Michael Liimatta, Director of Education International Union of Gospel Missions 1

2 Preventive Maintenance at Rescue Missions What is Preventive Maintenance Preventive maintenance is defined as routine, recurring work required to keep a facility and its equipment in such a condition that they can be used at original or design capacity or efficiency. This is very different from repair or breakdown maintenance, which is the restoration of a facility and its equipment to a condition equal to original or design capacity and efficiency by replacing parts or materials after they have deteriorated. For a task to qualify as Preventative Maintenance, it must consist of previously defined work, such as lubrication, filter change, cleaning, etc.; it must cost less than a predetermined budgetary limit for PM work; and it must be suited to scheduling. In many rescue missions, a carefully structured and monitored preventive maintenance (PM) program has yet to become standard practice, although more than likely PM exists in some form. The main object of PM is keeping facilities and equipment operating at the lowest total maintenance cost while at the same time prolonging its useful life. Even rescue missions without a formal program have someone who cleans, greases, oils, and adjusts critical machinery components, perhaps on a part-time basis. A mission s maintenance efforts, ideally, should be divided into three types of work: 1. Scheduled PM - Cleaning, making minor adjustments, lubricating, testing, measuring, and replacing minor parts 2. Scheduled Corrective Maintenance - Overhauls, alterations, replacements, and correction of problems found by PM inspections 3. Unscheduled Breakdown Maintenance Unplanned replacements and repairs. One of the underlying goals of a PM program is to attain a minimum total maintenance cost. Before manpower resources are allocated to the PM effort, maintenance management should examine the total cost picture and compare total maintenance cost to breakdown maintenance cost. The maintenance effort comprises several cost items: direct cost of maintenance excluding breakdown repairs; direct cost of breakdown repairs; indirect cost of maintenance, such as supervision, inventory, and other overhead expenses; indirect cost of breakdown maintenance; and estimated value of production losses from equipment breakdowns. Total maintenance cost includes direct and indirect costs, and total breakdown cost includes direct and indirect breakdown costs, plus production losses. 2

3 Monitoring these costs is essential to assessing the effectiveness of a PM program, once it is begun. Initially, not more than 6 to 8 percent of total manpower should be devoted to the PM program, although this percentage varies from rescue mission to rescue mission. If the total maintenance cost, including labor cost, increases after the program is started, the program should be reappraised, Fig. 2. Advantages of PM A well managed PM program has many advantages: A gradual decrease in overall maintenance costs. A functioning PM program should reduce total maintenance man-hours 15 to 20 percent. Detection of potential equipment failure. Corrective action can be scheduled, thereby reducing overtime expenditures. More cost-effective management of materials and parts inventory. Fewer large repairs because of sudden breakdown. More useful equipment records that for the most part detail planned maintenance repairs rather than breakdown repairs, for which information may be incomplete. Identification of items with high maintenance costs. A morale boost for all maintenance department employees. There is a sense of accomplishment in performing systematic, scheduled work, instead of doing breakdown repairs, often at a frenzied pace. Proper data collection and compilation on a year-to-year basis. The PM program is a measurable work effort, helping to secure higher level management approvals for additional manpower or replacement equipment. What To Include in the PM Program Not all equipment can be included in a PM program. Breakdown maintenance is more economical for some equipment. When a rescue mission engineer decides what equipment to include in the program, he should ask several questions: 3

4 Is the equipment vital? If it fails, will it cause a safety hazard or a major operations breakdown? Does a PM inspection require a teardown of the equipment? how long would repairs take? Does the equipment have a standby that can be brought into operation without loss of effectiveness? Will the cost of PM exceed the cost of breakdown repair? How important is prolonging the life of the equipment? At some point, will the equipment need to be replaced because it is obsolete or because a better model is available? Establishing a Program A program can be started with one or two groups of critical equipment or by rescue mission area or building. Other equipment can be added to the program gradually. All items and equipment to be included must be listed. This list, unique to the facility, is updated whenever new equipment is added or existing equipment is dropped from the program. If an equipment identifying system is not in place, one must be developed. Use of abbreviations for major groups of equipment will simplify the listing process. For example, AC can stand for air conditioner and AC-A4 for air conditioner, annex 4. Next, a check list or list of practices for each type of equipment, such as one list for pumps, one for fans, one for water softeners, etc., must be prepared, Fig. 3. In most cases, the equipment submittals and vendor-supplied information are sufficient for completing a check list that itemizes what needs periodic attention. The portion of PM work performed while the equipment is running instead of shut down varies, depending on the type of rescue mission and on how well PM work is coordinated with the customer. To determine the frequency of inspections, the best source of information is, again, the vendor submittals. As time progresses, the frequency of inspections may be revised on the basis of feedback from mechanics who have performed the inspections and made notations on the check lists. A written procedure may be required for a complicated inspection. But in many rescue missions, very few items require a written procedure in addition to the check list. For some of the PM work, particularly lubrication schedules, predetermined routes will need to be established. In some maintenance departments, a specific group of workers are designated to do PM inspections rather than just anyone on the crew. If specific individuals are assigned to 4

5 PM, this work is less likely to fall behind because people are likely to fall behind because people are pulled away to do breakdown repairs. Finally, a system of scheduling the PM tasks must be established. This system will include frequency designations (noted in Fig. 3). The jobs can be scheduled manually or by computer. Documentation and Record Keeping A typical PM system requires five record keeping documents: Equipment data card. This card details equipment type, location, date of purchase, vendor, make, model number, vendor drawing number, and maintenance accessibility, Fig. 4. Master PM schedule. The PM schedule, listing jobs for the entire year, notes the equipment number, equipment location, scheduling frequency, trade (electrical, HVAC, or mechanical), date the task was scheduled, date the task was completed, estimated time required, and actual time required. Deferred PM report. This report identifies the equipment, its location, the scheduling frequency, the related trade, the shift designation, and the date scheduled. An analysis of this report may uncover one or a combination of three situations: The trades assigned to the PM are not performing as anticipated; in other words, the actual time expended is significantly greater than the time estimated for the inspections. The scheduling frequency needs a review and reappraisal. Or the equipment may not belong in the PM program. Equipment history card. An equipment history card gives a brief description of repairs completed during the operating life of a piece of equipment, the date of each event, the PM frequency, the time charged, and the materials cost for work done. It should not include routine PM inspections, but should reflect repairs and replacements. The equipment breakdown report. This report is an excellent communications tool for the mechanic investigating the incident, his supervisor, the section maintenance supervisor, and the skilled trades assigned to resolving a problem. The report notes the cause of the breakdown and the repairs required. It records by trade the time expended to correct the situation. Depending on the size of the maintenance department and the size of the PM program, the work of preparing the check lists, planning and scheduling, and updating the the PM database may be entrusted to the supervisor for planning and scheduling, to be accomplished along with his other duties. In some cases, clerical help may be needed for accumulating, processing, filing, and issuing PM check lists. In many rescue missions only about 10 hr/wk are required for directing the PM program, once the initial work is 5

6 done. Successful implementation of a PM program is enhanced if operating manuals are available for all equipment under the ownership of the maintenance department. Other systems that will help ensure the success of the PM program include; An equipment filing system, manual or computerized, that is maintained and updated from the day a piece of equipment is installed and begins operation Aequate training program for the maintenance mechanics, electricians, and supervisors; a work order system that requires written authorization for all work A systematic planning and scheduling effort that uses the available manpower efficiency; an inventory control system under the direct control of the maintenance department to ensure economical use of resources and the availability of critical parts A well-defined structure for the maintenance department and for its relationships with other departments. Startup Recommendations If a rescue mission does not have the manpower to start a PM program, the department may want to hire a consultant to set up the system. In most cases, this work can be done with a payback period of two years or less. Another option is to start small, for example, beginning with the major HVAC equipment and then adding, as time permits, pumps, chillers, instrumentation, controls, and other equipment. One of the benefits of having the maintenance staff start a PM system themselves is that they learn from their mistakes and gain a sense of pride and accomplishment in developing the program that is not realized when a consultant does the work. Creating a preventive maintenance (PM) planning guides will allow maintenance management to calculate the cost of a proposed PM program on the basis of specific actions, frequencies, and equipment. The guides will aid in getting a program started quickly and in making adjustments as conditions change. For example, the intensity of the program for an equipment group or area can be quickly changed by changing the frequency of actions. The planning guides also provide a good program summary, so that objectives of the program can be explained clearly to plant management. Before an effective PM program can be developed, however, both maintenance and operations managers need to agree on what PM means. The planning guide discussed in this article suggests that it should mean 6

7 CARE, an acronym for these PM actions: Cleaning--cleaning equipment on a routine schedule Adjusting--making adjustments on a routine schedule Replacing disposables--replacing filters, lubricants, and other parts considered to be disposable on a routine basis Examining--examining and inspecting equipment on a regular schedule. A repair made before a piece of equipment fails is not preventive maintenance and should not be confused with PM tasks. This type of repair is corrective maintenance and is one result of PM. Using planning guides to set up a PM program will help in getting the action started by suggesting to maintenance management a list of what needs to be considered. The planning guide outlines various elements of information required to organize and carry out a complete PM system, Fig. 1. If a maintenance department is responsible for 500 pieces of equipment, as many as 10,000 pieces of paper could be generated in making up separate daily, weekly, monthly, quarterly, semiannual, and annual check sheets for electrical, instrumentation, and mechanical crafts. However, planning guides can reduce these 10,000 hseets to less than 50. The planning guides group common equipment so that several items can be covered on one sheet. The completed planning guides become the foundation for a PM system. The guides, which typically take 2 wk to complete, make up a PM generator file. Using the guides, a maintenance manager or foreman can develop check sheets (showing what components to check and what defects to look for) on individual pieces of equipment, if necessary, and can prepare a yearly schedule for all PM work. The first draft of a PM program is unlikely to be perfect. On the initial attempt, inclusion of 80 percent of the equipment that should be part of the program is a good objective. The major steps to be taken in completing the planning guides and establishing a PM program are shown in the flowchart, Fig. 2. The chart includes a step for developing check sheets for craftsmen to use when doing assigned PM work. There are three levels of checking to be considered for inclusion on a check sheet: 1. What components to check (included on the planning guide) 2. What to check for (defects and symptoms) 3. The limit of defect that is acceptable. Maintenance must decide what equipment requires individual check sheets. 7

8 One of the final steps on the chart is preparing the PM schedules or reminder file. This file will include PM actions to be taken on both long and short cycles. Some jobs may be required on each shift, while others are done only every 5 yr. The first overall steps shown in the flowchart entail completion of the planning guides for each equipment group. Each of the blocks on the sample guide is explained in the following paragraphs. The planning guide may be modified to fit the needs of the individual plant. 1. Equipment Description -A type of equipment that represents a group of specific machines, such as belt conveyors, should be designated. When equipment groups are identified, common elements should be considered instead of the differences between individual machines. Belt conveyors have different lengths, widths, drives, cleaners, etc., but they can be covered on one planning guide, Fig. 1, rather than completing a different sheet for each conveyor. Other planning guides cover lathes, drills, liquid transformers, and so forth. Generally, conventional plant equipment, which is 80 percent of all equipment, can be covered in about 15 groups. As a further example, Fig. 3 notes two types of equipment commonly found in a plant handling granulated materials, and lists the components that will require PM. 2. Equipment Number - Once the planning guides have been completed for equipment groups, it may be desirable to make inspection check sheets for certain individual pieces of equipment. In this case, the equipment identification number will be required on the sheet. 3. Criticality - Classifying equipment according to how important it is to the total plant operation acts as a reminder to stress PM on equipment vital to plant operations and not to care too much for other equipment. An example of class A criticality is the main transformer that feeds the plant. Another example would be the pump that provides critical cooling water to a process. Even when there are back-up pumps, this pump may be classified as critical. 4. Classifying equipment according to criticality will help put the emphasis for PM where it will do the most good. When the costs of a proposed program are added up, the program may not be totally affordable. The criticality designation will help identify where to cut back first, if deletions must be made. 5. Condition - The conditions under which equipment operates will affect the frequency and kind of care given to it. The amount of heat, dust, moisture, and vibration and the type of loading are examples of conditions affecting service life. This designation may not be as useful when the group sheets are made up, as it would be when check sheets for individual units are made up. 8

9 6. Components - The functioning parts of the equipment are listed. Housings should be included if they are under stress and could crack. One standard description should be used for each component, so that same or similar items are considered only once. For example, a bearing is a bearing, although there are babbitt bearings, sealed bearings, oiled bearings, greased bearings, and so forth. 7. Standard Defect or Symptom - A simple code can be established for defects and symptoms. The code should represent the terminology commonly used in the plant. A space can be made for "other defects" that do not fit into the code categories. 8. PM Action - The type of PM action, whether cleaning, adjusting, replacing disposables, or examining the condition of the equipment, is noted with a dot or an X in the proper column. In the example, no actions performed automatically are shown. This PM plan provides for actions based on the condition of the equipment only. 9. Running or Down - It is important to indicate whether the equipment must be down to perform the PM. Generally, if 50 pieces of equipment are inspected in a plant, about half the inspection points can be checked while the equipment is running. 10. Craft or Operator - In this column, a numerical or letter code is used to identify the craft or production operator who will be responsible to do the task. 11. Cycle - The frequency of action is recorded at three levels of intensity. Under "minimum," the lowest frequency thought to be responsible should be noted. Anything less than this minimum action would be negligent and likely to result in the destruction of the equipment. The minimum frequency could be zero; the PM could be skipped altogether. Under "maximum," the greatest frequency that management can be expected to budget should be noted. The "average" would be an inbetween point. The same frequency may be used in more than one of the three columns. For instance, the minimum frequency and the average frequency could both be once a year. 12. Time - The time required to do the PM action for all inspection points on the machine should be estimated. Time estimates should be marked with a "V" for "variable," if the time will change according to the size of the equipment in the group. The time it takes to get to the equipment should not be included. Travel time varies with the route taken. The time estimates should be reasonable numbers that the maintenance department can live with. Part of the purpose in preparing the planning guides is to gauge the size of the preventive maintenance effort. Maintenance can further use the guides to re-evaluate what PM is needed most and what can be defended when money is scarce. It is important to realize that even an active PM program may not be enough to eliminate breakdown maintenance. If equipment is operated beyond its capacity, if equipment is not released for PM, if the organization does not foster a caring attitude, or if other parts of 9

10 the maintenance management program are not ready, breakdowns may still occur. Yet, beginning an active PM program is a big step in the right direction. Common Problems With PM Programs Some of the problems that lead to the demise of preventive maintenance programs: Non-dedicated staff. The first mistake that many institutions make is setting up a preventive maintenance program with personnel that also do other maintenance functions. Ideally, preventive maintenance and regular maintenance personnel should have separate work schedules and should not intermix work unless there is an emergency situation. By hiring a dedicated preventive maintenance specialist, educational institutions will be able to better address needs for upkeep and improve their buildings' longevity. Inadequate documentation. A program that is run on the word of a technician that work is completed may very well get into trouble. Not because the technician is not being truthful, but because this type of program usually results in disorganization. Documentation and organization keep everyone involved informed and efficiently managed. This can be accomplished by instituting a system that automatically generates work orders for tasks. It should include periodic checks by a supervisor to see that the work is being completed and performed properly. Detailed logs and other documentation are also important for this system to work. Focusing only on the obvious. Preventive maintenance is usually perceived as a problem in mechanical, plumbing or electrical systems. Although these areas tend to cost large amounts of money when not adequately maintained, there are other areas that are costly if not properly maintained. Unclear responsibilities. There is no better way to discourage people than to give them an overwhelming task and then complicate it further by making it impossible to get everything they need to do done. Preventive maintenance should be conducted by a system with clear-cut parameters so that there is no misunderstanding of what regular maintenance staff takes care of and what preventive maintenance staff does. Short-sighted thinking. Most people want to see a solution as a panacea. The best strategy is to show that the program will cost more at the beginning, but that the savings will quickly offset the initial price. 10

11 Lack of early representation. Construction of facilities is the single largest investment an institution makes; extensive remodeling of older facilities approaches that cost in many cases. During the planning of these projects, there is usually no representation from those who have to use and maintain the building. The ideal time to formulate a preventive maintenance program is during the planning of new or retrofit construction. Including those responsible for maintaining the building on the planning committee creates insight into possible future maintenance problems with design and product selection. Computerized Preventative Maintenance Preventive maintenance (PM) on rescue mission properties is a lot like taking vitamins. If done right, it can be is simple, but does require forethought, and it must be done consistently and with care. As in other facets of the workplace, computer technology is changing the way property managers use manpower and train their staffs An effective computerized maintenance system can organize a property's past, present, and future. On the simplest level, it typically generates work orders according to schedule, and issues reminders or "ticklers" if tasks are not completed. It also can record which equipment is repaired, when, and by whom. A PM program can also track expenses and purchasing requirements. Using a computer to organize PM activities eliminates the inconvenience of trying to keep track of things in 3-ring binders or searching for pull-out cards hanging from the equipment itself. And, it can be useful in tracking costs. Still, a PM computer file is as good as the tasks you decide upon and put into it. The real work is discovering those tasks and ensuring that all the proper ones go in. There are a variety of PM software packages available. Creating a plan from scratch is another option. The choice depends upon the size and complexity of the system and size and expertise of in-house personnel. Most of the necessary data to which would be inputted into a PM software program probably already exists in spreadsheets, envelopes, notepads, and old manuals. Another benefit of "off the shelf" software is its ability to communicate and share data with other systems. For instance, they can be set up to like to the mission s accounting system. Essentials of Computerized PM 1. To work in a mission environment, computerized PM must be user-friendly enough to be accessible to the least computer-literate person working with it. 11

12 2. The best way to make sure it will work for you is to use a team approach and determine the goals up-front. Enlist staff cooperation by showing what a good preventive maintenance program means to them: Fewer emergency repairs and more peaceful nights without telephones ringing and beepers going off. 3. Focus on big buildings first, where the need for automation is greatest,. Eventually the system will filter down to some level; a PM model is necessary for all properties. 4. The experts suggest that you start small, one piece or function and extend it gradually. 5. A PM system must be reviewed from time to time once it is up and running. One recommendation is a formal review on a quarterly basis to determine PM effectiveness and efficiency. The evaluation should include questions such as: Does the work order give us the information we need? Is so much time spent on filling out paperwork that we lose productivity? Should we change work orders or procedures because of new equipment and/or manufacturers' recommendations? Should we change work orders or procedures because of new city or state codes? Some facilities specialists say that computerized preventive maintenance makes it easier to check work on a random basis. Work orders can include spaces for ranking performance. In some instances, co-workers check each other's work, too. Ultimately, the purpose of any new equipment or technology is to keep building systems operating as efficiently, economically, and painlessly as possible for all involved. End Notes: Much of the material for this reading was taken from the following articles: 1. Recipe for disaster. (Maintenance Management) Richard Shaw, American School & University, May The preventive maintenance planning guide: a tool for getting the PM program started on the right track. Jack Brown. Plant Engineering, March 8, Preventing maintenance stress. (building maintenance) Pearl Bosco. Buildings, Nov Establishing a preventive maintenance program, J.B. Singh and Russell M. Allen, Public Works Engineering, Feb 27,