Before Reliability-Centered Maintenance. The Manufacturing Enterprise

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1 Before Reliability-Centered Maintenance. The Manufacturing Enterprise By Alexander D. Douglas Jr., Manager of Equipment Reliability and Maintenance, JDS Uniphase, Flex Products Santa Rosa, California Key Words: Reliability-Centered Maintenance Management Availability Reliability ABSTRACT Reliability-Centered Maintenance (RCM) [1] is arguably the best tool for improving factory production equipment performance. Some organizations have tried to use RCM and failed, others are reluctant to attempt to use it. The most often cited barriers are organization size and technical prowess. Technical prowess is important, but organizational size is not. What is important, in addition to technical prowess, is the mission, mindset and structure of the manufacturing enterprise. This paper is directed at the maintenance policy designer and will focus on the important aspects that must exist in the manufacturing enterprise in order to successfully implement and sustain the RCM process. INTRODUCTION Today s high-volume, vacuum thin film roll coaters in use in the industry are complex machines with sophisticated control systems. Finding the right combination of processes, coating materials, substrates, and equipment configurations in order to get the desired performance and throughput can be difficult. These specialized equipment configurations have been prone to breakdowns, which result in undesirable product performance, coating rates, or safety / environmental hazards. If the maintenance policy designer determines that the application of RCM will improve the performance of these machines then the planner must determine if the manufacturing enterprise is willing and able to support that effort. This step should not be taken lightly. Without executive long-term willingness and support, the RCM process has little chance of being the technically sound and cost effective approach that it can be. The manufacturing organization has to adapt to new ways of thinking, to a new structure both physical and administrative. Presented here are a few of the critical aspects for a successful launch and sustained performance of RCM. H0W TO DETERMINE IF YOU RE ENTERPRISE CAN SUCCESSFULLY IMPLEMENT RCM LIST OF CRITICAL ASPECTS: 1 1. Does senior management want equipment performance improvement? 2. Does senior management know what performance is needed to be successful? 3. Can the enterprise create a consistent, comprehensive list of performance goals and metrics then track equipment performance? 4. Can Availability and Reliability be used to measure performance? 5. Is the current safety program sufficient to allow low risk manufacturing? 6. Is the Maintainer Function assigned into Manufacturing? 7. Are the existing Maintainers willing and able to do failure mode investigation? 8. Do Maintainers consider PM activity important? 9. Do the Maintainers have appropriate infrastructure? 10. Can the enterprise determine which functional failures have the highest consequences? 11. Is the enterprise capable of converting failure mode information into mitigating action? DESIRE OF SENIOR MANAGERS Assure the enterprise strategy includes a desire to gain a competitive edge by continuously improving the performance of the existing manufacturing equipment. In every organization where there is a senior level desire to improve equipment performance, it happens. The desire to improve equipment performance should be included in mission statements, strategic imperatives, budget plans, and in the attitudes of senior managers. 2 WHAT IS SUCCESS.. Understand the enterprise strategy and mobilize the maintainers to support it. Assuming the senior managers want to improve equipment performance then the maintenance policy designer has to be part of the enterprise strategy process. This is a high priority. The designer must think in company terms, not maintenance terms. Alexander D. Douglas Jr. Page 1 of 4

2 Understanding the enterprise strategy in terms of manufacturing equipment performance requirements, the safety, health and environmental impact risks that the enterprise is willing to accept, the product quality requirements and how much money is available all figure into the breadth and depth of the maintenance policy designs. The key question is what must be done to ensure that any asset achieves and continues to do whatever senior management wants it to do in its present operating context? 3 GOALS, METRICS AND PERFORMANCE Can the enterprise create a consistent, comprehensive list of performance goals and metrics, and then track performance? The designer should develop goals that include all the important metrics that indicate improved equipment performance. These include metrics for personnel safety, environmental protection, machine availability, machine reliability, product quality, product yields and budget control of both the maintenance function and the maintenance spent in the manufacturing departments. Each of these goals / metrics can be specified in a way that best fits the needs of the enterprise and desires of the executives. 4 TWO PRIMARY METRICS. Use Availability and Reliability as the primary equipment performance metric. There are many ways to measure manufacturing equipment performance. Lost time is one of the predominate effects of poor equipment performance. Two lost time metrics; availability and reliability, when properly applied can clearly describe the equipment performance. The SEMI E E [3] specification describes six different equipment time states with five time classifications. NON-SCHEDULED TIME In that same specification two time metrics are defined, availability and reliability. Availability- the probability that the equipment will be in a condition to perform its intended function when required. [3] The availability metric is easily applied using Operations Time, and Equipment Uptime. Availability (%) = {[Equipment Uptime x 100] / [Operations Time]} See Figure 2 below. % Availiability Coating Platform XYZ PLANNED vs ACTUAL FY % 90.0% 80.0% 70.0% 60.0% 50.0% July Figure 2 August September October November December Reliability - the probability that the equipment will perform its intended function, within stated conditions, for a specified period of time. [3] The reliability metric can be applied by measuring the percentage of successful coating runs with respect to the runs attempted. January February March April May June Equipment Downtime UNSCHEDULED DOWNTIME SCHEDULED DOWNTIME Total Time Reliability (%) = {[Total # of successful runs x 100] / [Total # of Runs Attempted]} See Figure 3 below. ENGINEERING TIME Operations Time Equipment Uptime Manufacturing Time STANDBY TIME PRODUCTIVE TIME EQUIPMENT STATES STACK CHART Figure 1 Alexander D. Douglas Jr. Page 2 of 4

3 Reliability 80 (%) 70 Runs 60 without 50 breakdown Figure 3 5 Example Equipment Reliability (100 run random sample / year) ASSURE THE SAFETY PROGRAM WORKS Is the current safety and environmental program sufficient to allow low risk manufacturing? If you cannot determine the current effectiveness of the current safety & environmental program then a word of caution is in order. Many believe that historical information about breakdowns is the most effective way to formulate a failure management policy. However RCM [1] advises that formulating a maintenance policy by collecting equipment breakdown history is contradictory. Resnikoff [2] made a statement that describes that contradiction. The acquisition of the information thought to be most needed by maintenance policy designers-information about critical failures-is in principle unacceptable and is evidence of the failure of the maintenance program. This is because critical failure entails potential (in some cases, certain) loss of life, but there is no rate of loss of life, which is acceptable to an organization as the price of failure information to be used for designing a maintenance policy. Thus the maintenance policy designer is faced with the problem of creating a maintenance system for which the expected loss of life will be less that one over the planned operational lifetime of the asset. This means that, both in practice and in principle, the policy must be designed without using experiential data which will arise from the failures which the policy is meant to avoid. This is especially true in the area of hidden failures, where the consequences could be a fatality or serious injury or significant adverse environmental impact. This apparent contradiction can be mitigated if the enterprise has in place a significant hazard abatement process and or a track record of safe operations MAINTENANCE FUNCTION REPORTING Maintainers exist to service manufacturing. Manufacturing is responsible for producing quality product, on time and at a cost that produces the expected profit. Equipment difficulties often stand in the way. The manufacturer may need technical support to overcome these difficulties. Manufacturing priorities often change with respect to the annual budget, manufacturing plan, and the current rate of revenue. Quick technical changes might be necessary. Quick technical response is essential and the maintainer can do that. Engineering designs the products, develops the process and the process instruction and also designs the equipment to be safe and capable. In cutting edge technology there may be differences between what the manufacturer needs and the tools that engineering has supplied. The maintainers have three responsibilities 1) To provide immediate technical support to manufacturing. 2) To maintain the configuration of the equipment as supplied. 3) To act as the manufacturing representative in order to affect engineering change. Organizationally then it makes the best sense for maintainers to report to manufacturing. 7 EXPECT MORE FROM MAINTAINERS Expect maintainers to do more than respond to breakdowns. Assure maintainers understand that improving equipment performance and sustaining that improvement is just as important as being on site to respond to unexpected breakdowns. Assign maintainers the responsibility to lead the investigations into determining the fundamental failure modes (RCM speak for root cause), to determine the best course of action (using RCM guidelines) and to assure that action is taken. Sometimes the maintainer can do this alone and sometimes it takes help from operators, engineers, vendors, and management. Other types of work historically assigned to maintainers should be avoided, such as designing equipment modifications and fabrication. Maintenance on equipment or facilities where performance improvement is not required or expected should be contracted and operated like a utility. The focus for the in house maintainer is sustained improvement. Are the maintainers able to do this? 8 DO THE PM S.. Doing the PM s on time is just as important as responding to breakdowns. Design the PM Program to sustain the improvement gained by failure mode investigation and mitigation. All PM s created should be connected to an expected or experienced failure mode of significant consequence. Complete all PM s on time. This includes PM actions taken by contractors. The On-Time completions metric is 100% for safety and environmental PM s and greater that 98% for others. The PM work instructions should include a statement that spells out the failure mode the PM is Alexander D. Douglas Jr. Page 3 of 4

4 designed to prevent. In addition the work instructions provides materials used, where the material is stored, the tools used, where the tools are stored and how to dispose of waste. All PM s should be technically sound and economically justified. [1] 9 WHAT MAINTAINERS NEED. Infrastructure support for maintainers is critical. Maintainer effectiveness can be enhanced if the infrastructure is organized, and efficient. Critical systems like materials, tools, instruments, fixtures, technical information, and equipment repair history and modification history used by the maintainers on a day in and day out basis need to be well organized, well situated and easy to use. Documentation is important but not the documentation you think. To perform good RCM investigations requires a fundamental functional understanding of the device, system or machine. Rarely documented is the design intent of a device. The design intent is a key to understanding the device function. For existing equipment it is imperative to understanding how the system under consideration works before attempting to determine how it fails. Improve personnel experience and training. 6) Do nothing. SUMMARY: Use the list of critical aspects and answer the questions. The answers will indicate what should be done. The expectations are that not all the answers will be favorable. Some have greater effect on the success for implementing RCM than others. (For example) If the enterprise is not able to determine what performance is needed, then performance improvement is ambiguous and RCM has no target. If the material system is not what is should be, it could be developed along with the RCM process. One is a showstopper, and one isn t. As a reminder I have again listed the critical aspects. 1. Does senior management want equipment performance improvement? 2. Does senior management know what performance is needed to be successful? 3. Can the enterprise create a consistent, comprehensive list of performance goals and metrics then track equipment performance? 4. Can Availability and Reliability be used to measure performance? DO FUNCTIONAL FAILURES OF HIGH 10 CONSEQUENCE FIRST. Use experiential 5. Is the current safety program sufficient to allow data to guide your efforts. Use this advice low risk manufacturing? only if your factory already has a large built in asset base that is not performing as wanted or expected. Deciding where in the factory or what part of a specific asset is exhibiting the most difficulty should be a continuous fact based exercise. Collect data. Each failure should have associated with it a consequence. The consequence is the Is the Maintainer Function assigned into Manufacturing? Are the existing Maintainers willing and able to do failure mode investigation? Do Maintainers consider PM activity important? Do the Maintainers have appropriate impact on the enterprise not the equipment. infrastructure? Consequences include more than just lost production time even though one of the easiest measures of equipment 10. Can the enterprise determine which functional failures have the highest consequences? performance is lost time. Use lost time as a guide for 11. Is the enterprise capable of converting failure concentrating the efforts of the maintainers. CONVERT INFORMATION INTO 11 ACTION. Improving equipment mode information into mitigating action? GOOD LUCK.. performance is not a hard as you think. The REFERENCES maintenance policy designer has few avenues available to prevent the consequences of an equipment functional 1. Moubray J. Reliability-centered Maintenance, failure. Finding the right one in the right order is dictated by the consequences, and technical solution that applies. 2. Resnikoff HL. Mathematical Aspects of The planner has six main options. 1) Add or modify a Reliability-Centered Maintenance, Dolby proactive maintenance action. 2) Change the operation of the equipment. 3) Change the process recipe. 4) Modify the equipment or the software running the equipment. 5) 3. Access Press SEMI E E. Specification For Definition and Measurement of Equipment Reliability, Availability, and Maintainability (RAM) Alexander D. Douglas Jr. Page 4 of 4

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