Equipment Efficiency: Availability, P erformance and M aintenance

1. Equipment Efficiency:Availability, Performanceand Maintenance Operations Analysis and Improvement 2010 Fall Dr. Tai-Yue Wang Industrial and Information Management Department National Cheng Kung University

2. Presentation • The role of maintenance is to insure the survivability and proper functioning of all company hardware. • Most maintenance departments are considered “a necessary evil”. • Investments required to improve production processes usually take on a low priority.

3. Presentation • Maintenance evolution, as well as maintenance technique evolution, has developed in parallel for many companies. • Remediate hardware failures. • Prevent future problems with the equipment. • Incorporate basic maintenance tasks into their daily production routine. • Predicting equipment breakdowns.

4. Introduction • Maintenance’s primary objective is to maintain, at a high operative level, the productive resources in order to assure their service at an expected cost. • Maintenance is the “machine’s medicine”. • Determine the right moment to replace the equipment. • It may be better to simply unplug it.

5. Thinking revolution The 5S Visual Control Workforce optimization Standard operations Poka-Yoke Jidoka 1 20 11 12 9 TPM One-Piece flow Multi- functional workers 7 16 5 14 Leveling Production Kanban SMED 4 6 17 8 JUST IN TIME 15 18 19 13 10 3 2 Introduction • Elements that need maintenance. • Machines and tools. • Facilities (compressed air, heating,…) • Buildings (walls, illumination,…) • Information and transportation systems.

6. Thinking revolution The 5S Visual Control Workforce optimization Standard operations Poka-Yoke Jidoka 1 20 11 12 9 TPM One-Piece flow Multi- functional workers 7 16 5 14 Leveling Production Kanban SMED 4 6 17 8 JUST IN TIME 15 18 19 13 10 3 2 Introduction • Some companies subcontract maintenance. • Is contemplated in both the Just-in-time and the 20 keys (key number 9) for lean. • Improves the availability and performance rates of the equipment.

7. Types of maintenance • Corrective -> All industrial equipment is exposed to transitory (wear) or definitive breakdowns (catastrophic failure). • Affecting its functionality and performance. • Can represent high costs for enterprises. • Preventive -> The maintenance mission cannot only be repairing the breakdowns. • They should be able to get ahead of the breakdowns.

8. Corrective maintenance • Also called breakdown maintenance. • Up to the 1950s it was virtually the only maintenance. • Machine stoppages hardly affected productive time. • Repairs were carried out in an effective way.

9. Types of corrective maintenance • Urgent repairs. • Reestablishing the equipment into service. • Repair is carried out is temperally. • The remainder of the tasks will/can be scheduled for a future time.

10. Types of corrective maintenance • Scheduled corrective. • Appears as a result of urgent repairs. • Determine an appropriate time to repair the machine completely. • After repairing the damaged component • As good as new. • At least as it was before.

11. Repair problems • Repair tasks are performed quickly and under pressure, which can cause future problems. • Repair time can be very high because replacement part(s) may have to be ordered from a supplier.

12. Repair problems • Accidents can take place because of poor maintenance safety measures. • Corrective maintenance policy implies higher labor costs. • This policy can be justified in some cases. • Equipment with a frequent replacement policy. • Like personal office computers. • When breakdown costs are small. • Light bulbs fail.

13. Types of preventive maintenance • The preventive maintenance has two variants. • Systematic preventive maintenance. • Conditional preventive maintenance or predictive maintenance.

14. Systematic preventive maintenance • 1960s -> the General Electric Corporation systematized a new type of maintenance called planned maintenance.

15. Systematic preventive maintenance • Planned maintenance arrived to Japan. • The bases of this systematic preventive maintenance process were established. • Systematic substitution of some machine components.

16. Systematic preventive maintenance • Applied to general wear or use components. • Know with precision the component’s performance characteristics.

17. Systematic preventive maintenance • Replacement policy might call for a component to be replaced every week or in other ways such as, every 300 working hours or every 1000 parts produced.

18. Conditional preventive maintenance • Also called predictive maintenance. • Systematic preventive maintenance can become very expensive.

19. Conditional preventive maintenance • Conditional preventive maintenance is used to change components depending on their current state. • The useful life for costly components can be extended. • This type of maintenance best fits components where performance can be monitored.

20. Conditional preventive maintenance • ISO 14000 (environmental norm) requires that industry avoid systematic preventive maintenance when working with environmentally harmful products.

21. Conditional preventive maintenance • Predictive maintenance. • Look for correlations between multiple parameters and the degradation of a component. • Temperature (thermocouples), • Noises (phonometer). • Cracks (X-rays machine). • Pressure losses (manometer). • QS9000 recommends predictive maintenance.

22. Maintenance program implementation • Almost all machines follow a similar lifecycle. • Hidden small defects. • Difficult to detect and to observe -> It does not interfere with functionality. • Increase of friction in an axle. • Apparent small defects. • Are more noticeable-> They are normally not repaired. • Small vibrations on a machine.

23. Maintenance program implementation • Execution under expectations. • The defects affect the equipment productivity. • the standards of quality will be violated.

24. Maintenance program implementation • Almost all machines follow a similar lifecycle. • Intermittent stops. • The machine intermittently produces defect parts. • Small repairs are performed. • Stops and breakdowns. • Breakdowns are frequent. • Production equipment may not be as new as we would like them to be. • “Stops and breakdown” stage.

25. Maintenance program implementation • Production equipment typically becomes more sophisticated/complex. • More expensive every year. • It has greater economic impact. • Repairs should be done at a faster rate. • Working shifts can also represent an obstacle for maintenance interventions. • Limits possible maintenance tasks and scheduling.

26. Maintenance program implementation • The objective of maintenance is to efficiently oversee equipment throughout the equipment life cycle. • Cover the entire lifecycle • Implementing an effective corrective maintenance. • Preventive maintenance tasks. • Implementing predictive maintenance strategies.

27. Getting started • Become familiar with the resources that will require maintenance. • Each maintained resource should be coded (resource id#). • Code the types of breakdowns and maintenance tasks. • In a historical data study -> Group failure causes.

28. Getting started • Maintenance should have the following two documents. • Facility Inventory. • Lists all equipments and their principle characteristics. • Code, record number, equipment type,… • Equipment History Files. • Data given by the equipment manufacturer. • Information about the location in the plant. • Types of spare parts needed. • …

29. Corrective maintenance implementation • Organize, in an effective way, the corrective maintenance procedures and actions. • Breakdown occurs -> Fill out a breakdown work order. • If the worker can solve it -> fill a report. • If not -> the work order will be sent to the maintenance department. • Work request order will be issued. • Maintenance workers will either repair the machine immediately or will schedule the repair. • The repair can be provisional or definitive.

30. Scheduled corrective maintenance • Variability in the corrective maintenance tasks duration can be problematic. • Corrective orders and flow diagrams for repetitive repairs must be developed. • Materials and spare parts that should be utilized. • Maintenance workers’ tasks do not end with the equipment repair. • They should gather all the breakdown information. • Describe the process that was performed.

31. Scheduled corrective maintenance • Each machine should have its own file with breakdown records. • Analyze breakdown causes. • Anticipate future problems. • This file must be upgraded with each maintenance intervention.

32. Scheduled corrective maintenance • Corrective maintenance tasks do not only consist on changing the broken or malfunctioning components. • Study the causes and the frequency of the breakdowns.

33. Preventive maintenance implementation • Avoid a breakdown of any resource, while keeping maintenance cost as low as possible. • Two types of actions. • Inspections. • Observe and detect possible anomalies. • Frequent checkups that follow a specific inspection plan. • Revisions. • Scheduled equipment stops. • Systematic substitution of several machine components. • Carried out during the weekend.

34. Preventive maintenance implementation • Preventive maintenance tasks’ scheduling is mandatory in the ISO norms.

35. Preventive maintenance implementation • These tasks can be planned daily, weekly, monthly or even annually. • Scheduled at times when they do not affect the factory’s production plan. • Daily working problems force us to continuously reschedule these tasks.

36. Preventive maintenance implementation • Equipment preventive maintenance tasks are also called PM orders. • Each PM order should be based on a study of the equipment breakdown causes. • FMEA tool described at the tools section.

37. Autonomous maintenance • PM orders carried out by the production workers. • Known as user maintenance orders. • They should be simple and graphically represented. • Many inspection tasks should be carried out every day.

38. Autonomous maintenance • Significant amount of notices that could be easily handled by the production worker. • It takes more time to fill out the request order than to fix the problem

39. Autonomous maintenance • Autonomous maintenance includes these small tasks and three daily preventive measures. • Cleaning, lubricating and checking.

40. Autonomous maintenance. Safety • Safety is one of the most important restrictions. • Autonomous tasks apply only for simple repair operations. • Repair or maintenance should never be performed if the knowledge required to fix the machine is high.

41. Autonomous maintenance. Safety • It can be very challenging to convince production workers about the importance of maintenance tasks. • They do not consider their responsibility.

42. Autonomous Supervision 7 Process Quality Assurance 6 Autonomous Maintenance Standards 5 Overall inspections 4 Cleaning and Lubricating Standards 3 Countermeasures to Sources of Contamination 2 1 Initial cleaning Autonomous maintenance • Autonomous maintenance implementation process has a specific methodology.

43. TPM - Total Productive Maintenance • In the 1970s, Nakajima developed in Japan TPM. • New maintenance management philosophy. • English translation was not published until 1988. • JIPM – Japanese Institute of Plants Maintenance. • Grants the PM prize to the TPM top excellent companies. • 60% of the winning companies during the first 17 years are now part of the Toyota Group or suppliers of this Group.

44. TPM - Total Productive Maintenance • Nakajima combined preventive maintenance theories with the total quality concept. • Nakajima developed the Overall Equipment Efficiency ratio.

45. TPM keys • Maximize the Overall Equipment Efficiency. • Eliminating the six big losses. • Autonomous maintenance implementation. • In order to terminate the “I operate, you repair” mind set. • Preventive engineering. • Improving the equipments’ maintainability.

46. TPM keys • Training workers for maintenance improvements. • Propose methods for increasing the equipment availability. • Initial equipment management. • The objective of the TPM -> Zero Breakdowns. • Utilize tools such as the P-M analysis -> Explained in tools section.

47. RCM - Reliability Centered Maintenance • RCM was created in the United States in the 1960s, to optimize the reliability of aeronautical equipment. • RCM was not utilized in nuclear power stations until the 1980s. • Recently has been implemented in the industrial world.

48. RCM - Reliability Centered Maintenance • Needs a complete maintenance and breakdown record for each item of equipment. • RCM objective is to determine the maintenance tasks that are more effective for the critical components. • FMEA, reliability analysis, statistical techniques. • It is necessary to have a preventive maintenance program implemented and running properly.

49. FMEA for equipment • All defects have a root cause, and to eliminate future defects an action must be carried out. • Defect -> Gap between two elements • Cause -> Lack of lubrication or a loose fastener. • Action -> Grease or tighten the lose element.

50. FMEA for equipment • To determine a good preventive maintenance plan, all the possible breakdowns, their causes and their corrective actions must be analyzed. • The main tool to carry out this type of analysis is the FMEA for equipment (Failure Mode and Effects Analysis). • Is a guide to analyze, in an organized manner, causes of possible equipment breakdowns. • A group of workers is gathered to study the problems and failures