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A good plan is good for business
Breakdown maintenance still accounts for much of the time maintenance workers put in. Too often, the result is lost revenue, excessive downtime, and poor-quality repairs. This convenient, practical guide shows you how to develop a comprehensive planning and scheduling effort to ensure all resources are available when they are needed. You'll discover how to gather supportive data and build plans that will help you control maintenance costs and equipment downtime.
* Make informed decisions about the most effective way to perform maintenance
* Establish solid shutdown schedules
* Set reasonable goals based on your budget
* Understand a range of estimating and scheduling methods Structure a work order system that supports your plan
* Allocate money, material, and labor resources for maximum productivity
* Use multi-skill training to its best advantage
* Formulate methods to identify the right work to be performed during a shutdown
About the Author.
Chapter 1. Defining the Level of Maintenance.
Chapter 2. Estimating Methods.
Chapter 3. Planning and Estimating Electrical Work.
Chapter 4. Understanding Preventive and Predictive Maintenance.
Chapter 5. Scheduling Methods.
Chapter 6. Planning for Shutdowns, Turnarounds, and Outages.
Chapter 7. Gathering Data for Maintenance Performance Indices.
Chapter 8. Using Indices to Measure Performance.
Chapter 9. Using Multiskill Training.
Appendix A: Identifying Electrical Work to Be Performed During a Shutdown.
Maintenance of a plant or facility can be performed by default or by plan:
Maintenance by default simply means equipment is repaired as it fails-usually on an emergency basis. The rush to get the equipment running again may result in shoddy workmanship that costs in the long run. The downtime incurred by the operation usually occurs at an inopportune moment and can also cost money because of lost business.
Maintenance by plan simply means that there has been forethought in what level of maintenance is required. The level of maintenance eventually attained by a plant or facility depends on the condition of the equipment and the ability of that equipment to meet the needs.
To attain some control over the level of maintenance, organizations must move away from maintenance by default to maintenance by plan. A comprehensive planning and scheduling effort provides the basis for this control. Companies that have moved to a more planned approach tend to be better equipped to meet the numerous market changes encountered in recent years. However, the implementation of planning and scheduling at plants and facilities has had to compete with numerous other programs in recent years.
Any discussion of planning and scheduling must start with a discussion about these programs and how they support, or contradict, the move toward a planned level of maintenance. This chapter provides a high-level view of how you define, plan, and implement a level of maintenance.
Era of Business Management Theories
The period from the 1960s to the present is often referred to as the era of business management theories. Dozens of programs with three-letter acronyms, began cropping up in the 1960s, including the following:
MBO-Management by objective
MBR-Management by results
TQM-Total quality management
SPC-Statistical process control
TPM-Total productive maintenance
BPR-Business practice re-engineering
Management consultants made millions pushing the program-of-the-month, sometimes contradicting the program they pushed the year before. In spite of this self-serving agenda, many companies were still able to make real progress toward improving the way they did business. Of all the efforts implemented during this period, none has been more effective than total quality management (TQM).
Prior to the 1970s most quality-control efforts were centered on testing or inspecting the final product. If a product failed an inspection, it was discarded or reworked. Beginning in the 1970s, Japanese companies implemented what they called total quality management. Central to this effort was the reduction of defects in the process, at every point in the process. In fact, the goal was to have zero defects. Production workers were trained in statistical process control (SPC) and were given conditional autonomy to make changes that ultimately led to eliminating defects.
This new focus on eliminating defects not only succeeded in improving the throughput of manufacturing processes, but also had the side effect of reducing the overall cost of manufacturing. Japanese products became more reliable and cheaper than comparable products throughout the world. As a result, many North American and European companies adapted TQM in the 1980s. These efforts were largely successful and are credited with improving the overall quality of products and services throughout the world.
TQM touched every aspect of business. One TQM offshoot, just-in-time (JIT) inventory management, focused on a goal of zero raw material, work-in-progress, and finished goods inventory. Another offshoot was total productive maintenance (TPM), which extended the idea of autonomy and suggested that production line workers could also perform maintenance on equipment. One goal of TPM was to move preventive maintenance (PM) activities from an organized maintenance department to the production worker. The ultimate (and some may say far-reaching) goal was to move all maintenance activities to production personnel. This approach has had limited success in industry, mostly because of implementation problems. In some cases, production workers weren't properly trained to perform the work. In others, the maintenance departments with poorly established PM programs had nothing of substance to pass on to production workers.
By the 1990s, the zero-defect tenant of TQM started to lose its unconditional supporters. Quality for the sake of quality, with no eye toward the bottom line, was said to be just plain bad business. A new approach called business practice re-engineering (BPR) became the rallying cry for industry.
Based on a book by James Champy and Michael Hammer, Reengineering the Corporation (New York: HarperCollins Publishers, PerfectBound electronic books, 2003), BPR seemed to address the deficiencies in TQM by re-engineering a process to eliminate non-value-added activities. This often resulted in streamlining the process, eliminating steps, and eliminating people. The wave of downsizing in the 1990s was blamed, perhaps unfairly, on reengineering. BPR fostered the development of self-directed teams that signaled the end of some first-line and middle-management jobs.
The Movement to Reliability and Availability
A positive outgrowth of TQM and BPR was a movement toward improved equipment reliability. Many organizations began to develop programs, such as reliability-centered maintenance (RCM), to refocus maintenance on overall equipment reliability. RCM was developed in the electric power industry and has been adapted to a number of other industries. RCM founded a renewed emphasis on preventive maintenance (PM) programs and began to give credibility back to these efforts. Originally developed in the 1970s, predictive maintenance (PDM) programs were beefed up or expanded. Standards for purchase, installation, and repair of equipment were developed to ensure continuity as organizations continued to evolve.
However, just as quality for the sake of quality is unprofitable, reliability for the sake of reliability is equally wrong. Many maintenance reliability programs tend to take a bottom-up approach. Reliability tools are purchased and then are applied to any and all equipment to improve performance. A program such as this can result in costly efforts on some less-important equipment. The cost associated with improving reliability must be balanced against the return from the effort.
In a smart business, the market is thoroughly researched and a comprehensive sales plan is developed. An operations department uses this sales plan to determine what equipment availability is required. A maintenance department is consulted to determine what equipment reliability is required to provide the needed equipment availability. The following example illustrates this approach.
Once market share is determined, a sales forecast is made. Estimating the seasonal changes in sales and how they relate to plant capacity helps provide a production forecast. The plant capacity is the nameplate or design capacity, running 24 hours per day, seven days a week. Figure 1-1 shows a sales forecast for a year. (Each month has been assigned an equal number of hours to simplify the example.)
The first step in developing a production plan is to determine if enough plant capacity exists to meet the sales forecast. During the months of June through August, sales requirements exceed plant capacity. Therefore, this company must develop a production plan to build inventory and eventually meet sales requirements, even during these months.
The plant capacity line shown on the chart suggests the plant can produce at this level all the time. However, the nameplate rating on any equipment (or plant for that matter) comes with an unwritten caveat. The plant will run at capacity, but not indefinitely. Equipment will have to be shut down for maintenance from time to time. So, to achieve the operations availability, maintenance must also get custody of the plant equipment. Figure 1-2 shows a production plan with this point in mind.
The plant is scheduled to run below capacity each month, but the production level in the first few months is higher than the sales requirement. This allows for inventory to be built up and eventually meet the sales requirements of the peak months. Operation below capacity during each month allows downtime to be built into this plan. The maintenance department is charged with using this downtime to build capacity back into plant equipment.
With this production plan, the maintenance department can now discuss an intelligent schedule for operations uptime and maintenance downtime, called a custody plan. This plan identifies the custody of the equipment required by the operations department to manufacture a quality product and to attain the on stream-time needed to meet sales. It also defines the custody of equipment required by the maintenance department to build capacity back into the operation.
Planned Maintenance under Attack
Maintenance departments in facilities without such a custody plan receive custody of equipment only when it fails-this is maintenance by default. Breakdowns do not necessarily occur at the most opportune moments and tend to result in the most expensive maintenance work performed. Consider the example of a plant that runs around the clock. Studies have shown that only 24 percent of plant breakdowns occur during normal maintenance department work hours (Monday through Friday, 8 hours per day). This is not surprising, since this period accounts for 24 percent of the time in a normal workweek. For this reason, it should not be considered coincidental that the majority of breakdowns (76 percent) occur in the evening or on weekends, when less maintenance help is available. Usually, repairs performed by the maintenance department during breakdowns fall short of being planned, to say the least.
Maintenance by default, however, creates a plant environment that ultimately can be the demise of the business. When the maintenance department receives custody of the machinery only when it breaks down, its marching orders are to get the plant running again. This is a far different mandate from "fix the real problem." To get the plant running again, the repairs that are made are almost always repairs that treat the symptoms of the problems rather than the real problems.
A typical example of this situation would be a plant that originally was designed for a given production capacity, with all motors sized to operate within their nameplate capacity. Increases in production capacity with subsequent debottlenecking of the plant now have many motors running in an overload condition. The effect of this demand is a drastic reduction in motor life, sometimes burning up in a matter of months.
Under maintenance by default, the easiest and quickest fix is to replace the motors in kind, but the replacement motors will fail just as quickly as their predecessors did. The real fix, in this example, would require the next-larger horsepower motor, but this might require modification of the base to accept a larger frame, running new conduit, and/or pulling larger wire. It may also require a larger motor starter in the motor control center. Also, in maintenance by default, there is never time to fix the real problem. In a short while, other equipment problems will be causing additional emergency downtime. Eventually, the entire maintenance department may be consumed in applying bandages to many problems, but not really fixing any.
Some companies deal with this unfortunate scenario by equipping the maintenance department to be more responsive to emergencies. Outfitting the workers with radios or pagers enables maintenance supervisors to locate their personnel at a moment's notice so that personnel can be dispatched at will. Other companies supply computer terminals at operating machinery sites and install printers at maintenance worker benches so that machine operators themselves can send a request directly to a maintenance worker, bypassing any management control altogether. Some companies outfit maintenance shops with answering machines or voice-mail-boxes. Maintenance workers are required to check in regularly for messages and respond immediately.
All of these creative ideas ensure that emergency response is optimized, but do nothing to improve operating reliability. In fact, dealing with emergencies in this way only exacerbates problems and perpetuates emergency thinking. When maintenance focuses only on providing a quick response to emergency conditions, it ultimately removes the need to identify beginning equipment problems as anyone's responsibility. Short-term thinking begins to be the norm and equipment reliability degrades.
If a custody plan exists, maintenance knows when the equipment will be made available and has time to plan the jobs to ensure the highest quality repair. Using its custody of the equipment wisely becomes the challenge of a well-managed maintenance department. This sort of effort tends to separate the work performed into two broad categories:
Maintenance work performed during maintenance custody (shutdowns)
Maintenance work performed during production custody
Maintenance Work Performed during Maintenance Custody (Shutdowns)
The following defines maintenance work performed during maintenance custody (that is, during a shutdown):
Preventive maintenance (PM)-The PM work performed during a shutdown of equipment takes the form of manufacturer-recommended rebuilds, or rebuilds required because of predictable wear. Compressor and pump rebuilds, along with instrument calibration, are in this category. The PM interval (the time between PM shutdowns) is established from a manufacturer's requirements or a plant operating history. The job can be planned far in advance of the shutdown and should be the most efficient effort by the maintenance department.
Corrective work-This is the work performed to replace worn parts, adjust loose equipment, prevent a major failure, and return the equipment to nameplate condition. As with PM, this work can be planned in advance of the shutdown. To ensure that repairs are performed to at least a minimum standard, all replacement parts, tools, and sufficient labor required for the repair must be allocated prior to the shutdown.
Emergency repair-This is the occasional and unavoidable shutdown of equipment because of unforeseen circumstances requiring unplanned repairs.
Excerpted from Audel Managing Maintenance Planning and Scheduling by Michael V. Brown Excerpted by permission.
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