Operations Management Maintenance and Reliability Chapter 17 Transparency

Operations Management Maintenance and Reliability Chapter 17 Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -1 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Outline ¨ GLOBAL COMPANY PROFILE: NASA ¨ THE STRATEGIC IMPORTANCE OF MAINTENANCE AND RELIABILITY ¨ Improving Individual Components ¨ Providing Redundancy ¨ MAINTENANCE ¨ Implementing Preventive Maintenance ¨ Increasing Repair Capability ¨ TOTAL PRODUCTIVE MAINTENANCE ¨ TECHNIQUES FOR ESTABLISHING MAINTENANCE POLICIES Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -2 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Learning Objectives When you complete this chapter, you should be able to : Identify or Define: ¨ Maintenance ¨ Mean time between failures ¨ Redundancy ¨ Preventive maintenance ¨ Breakdown maintenance ¨ Infant mortality Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -3 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Learning Objectives continued When you complete this chapter, you should be able to : Describe or Explain: ¨ How to measure system reliability ¨ How to improve maintenance ¨ How to evaluate maintenance performance Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -4 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

NASA ¨ Maintenance of space shuttles ¨ Columbia: ¨ 86, 000 miles on odometer ¨ 3 engines each the size of a VW ¨ expected to make dozens more launches ¨ Maintenance requires ¨ 600 computer generated maintenance jobs ¨ 3 -month turnaround ¨ More than 100 people Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -5 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Maintenance Management ¨ All activities involved in keeping a system’s equipment working ¨ Objective: Maintain system capability & minimize total costs © 1995 Corel Corp. Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -6 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

The Strategic Importance of Maintenance and Reliability ¨ Failure has far reaching effects on a firm’s ¨ operation ¨ reputation ¨ profitability ¨ customers ¨ product ¨ employees ¨ profits Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -7 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Maintenance Performance Employee Involvement Maintenance Procedures Maintenance Performance © 1995 Corel Corp. Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -8 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Good Maintenance & Reliability Strategy ¨ Requires: Employee involvement ¨ Maintenance and reliability procedures ¨ ¨ To yield: ¨ ¨ ¨ Reduced inventory Improved quality Improved capacity Reputation for quality Continuous improvement Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -9 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Employee Involvement ¨ Information sharing ¨ Skill training ¨ Reward system ¨ Power sharing © 1995 Corel Corp. Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -10 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Maintenance & Reliability Procedures ¨ Clean and lubricate ¨ Monitor and adjust ¨ Minor repair ¨ Computerized records Maintenance Procedures © 1995 Corel Corp. Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -11 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Maintenance Benefits Lower operating costs Reduced inventory Improved capacity Maintenance Continuous improvement Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e Faster, more dependable throughput Higher productivity Improved quality 17 -12 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Tactics for Reliability and Maintenance ¨ Reliability Tactics improving individual components ¨ providing redundancy ¨ ¨ Maintenance Tactics implementing preventive maintenance ¨ increasing repair capabilities ¨ Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -13 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

System Reliability Components in Series 100 Reliability of the System (Percent) n=1 80 n=10 60 n=5 0 40 n= 10 0 20 0 100 n= 40 n= 0 30 0 n=200 99 98 97 Average Reliability of all Components (Percent) Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -14 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458 96

Reliability of Components in Series R = R 1 * R 2 * R 3 *. . . Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -15 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Evaluating Maintenance ¨ Reliability ¨ Probability that an item will function for a given time ¨ Mean time between failures (MTBF) ¨ Average time between failures of a repairable item ¨ Failure rate ¨ Reciprocal of MTBF Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -16 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Failure Rate (%) FR(%) = Number of failures Number of units tested Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -17 * 100% © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Lifetime Failure Rates “normal” failure Failure rate Wearout failure Infant mortality and improper use failure Lifetime Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -18 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Failures Per Operating Hour FR(n) = Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e Number of Failures Operating Time 17 -19 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Mean Time Between Failures MTBF Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 1 FR(N) = 17 -20 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Providing Redundancy Probability of first component + working Probability of second component * working Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -21 Probability of needing second componen t = P(R) © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Maintenance Decisions ¨ How much preventive & breakdown maintenance ¨ Who performs maintenance Centralized, decentralized, operator etc. ¨ Contract or in-house ¨ ¨ When to replace or repair ¨ How much to replace ¨ Individual or group replacement Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -22 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Types of Maintenance Preventive Breakdown ¨ Routine inspection & servicing ¨ Prevents failures ¨ Bases for doing ¨ Time: Every day ¨ Non-routine inspection & servicing ¨ Remedial ¨ Basis for doing ¨ Equipment failure ¨ Usage: Every 300 pieces ¨ Inspection: Control chart deviations Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -23 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Mean Time Between Failure and Preventive Maintenance Candidate for preventive maintenance will have distribution with low variability Frequency of failure Mean Time Between Failure Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -24 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Organizing the Maintenance Function ¨ Centralized maintenance department ¨ Does all maintenance (PM & breakdown) ¨ Decentralized maintenance department ¨ Useful if different equipment used in different areas of company ¨ Contract maintenance ¨ Used if little equipment or expertise ¨ Operator ownership approach Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -25 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Operator-Ownership Approach ¨ Operator does preventive maintenance Equipment condition is their responsibility ¨ Learns equipment better ¨ Increases worker’s pride ¨ Reduces repair time & PM costs ¨ ¨ Maintenance department is backup Handles non-routine problems ¨ Provides maintenance training ¨ Has plant-wide responsibilities ¨ Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -26 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

A Computerized Maintenance System Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -27 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Maintenance Costs Traditional View ost C ce n a en t n i a M l a st o Tot C ce n a n te n i a M e v i t en v e r P Cost Breakdown Cost Maintenance Commitment Optimal Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -28 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Maintenance Costs Full Cost View Cost Total costs Full cost of breakdowns Preventive maintenance costs Optimal Maintenance Commitment Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -29 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Contract for Preventive Maintenance ¨ Compute the expected number of breakdowns without the service contract ¨ Compute the expected breakdown cost per month with no preventive maintenance contract ¨ Compute the cost of preventive maintenance ¨ Compare the two options Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -30 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Increasing Repair Capabilities: Features of A Good Maintenance Facility ¨ Well-trained personnel ¨ Adequate resources ¨ Ability to establish a repair plan and priorities ¨ Ability and authority to do material planning ¨ Ability to identify the cause of breakdowns ¨ Ability to design ways to extend MTBF Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -31 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Operations Manager Must Determine How Maintenance Will be Performed Operator Maintenan Manufacture Depot Service ce r’s field (return Departme service equipment) Competence is higher as nt we more to the right Preventive maintenance costs less and is faster as we move to the left Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -32 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Total Productive Maintenance ¨ Additional requirements of: ¨ Designing machines that are reliable, easy to operate and easy to maintain ¨ Emphasizing total cost of ownership when purchasing machines, so that service and maintenance are included in the cost ¨ Developing preventive maintenance plans that utilize the best practices of operators, maintenance departments, and depot services ¨ Training workers to operate and maintain their own machines Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -33 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

A Key To Success High utilization of facilities, tight scheduling, low inventory and consistent quality demand reliability - total preventive maintenance is the key to reliability. Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -34 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458

Techniques for Establishing Maintenance Policies ¨ Simulation - enables one to evaluate the impact of various maintenance policies ¨ Expert systems - can be used by staff to help diagnose faults in machinery and equipment Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5 e, and Operations Management, 7 e 17 -35 © 2004 by Prentice Hall, Inc. , Upper Saddle River, N. J. 07458