Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-1
Operations Operations ManagementManagement
Maintenance and ReliabilityMaintenance and ReliabilityChapter 17Chapter 17
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-2
OutlineOutline GLOBAL COMPANY PROFILE: NASA THE STRATEGIC IMPORTANCE OF
MAINTENANCE AND RELIABILITY 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-3
Learning ObjectivesLearning 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-4
Learning Objectives - continuedLearning 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-5
NASANASA Maintenance of space shuttles Columbia:
86,000,000 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-6
All activities involved in keeping a system’s equipment working
Objective: Maintain system capability & minimize total costs
© 1995 Corel Corp.
Maintenance ManagementMaintenance Management
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-7
The Strategic Importance of The Strategic Importance of Maintenance and ReliabilityMaintenance 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-8
Maintenance Procedures
Employee Involvement
Maintenance PerformanceMaintenance Performance
© 1995 Corel Corp.
© 1995 Corel Corp.
Maintenance PerformanceMaintenance Performance
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-9
Good Maintenance & Reliability Good Maintenance & Reliability StrategyStrategy
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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-10
Employee InvolvementEmployee Involvement
Information sharing Skill training Reward system Power sharing
© 1995 Corel Corp.
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-11
Maintenance & Reliability Maintenance & Reliability ProceduresProcedures
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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-12
Lower operating
costs
Continuous improvement
Faster, more dependable throughput
Higher productivity
Improved quality
Improved capacity
Reduced inventory
Maintenance
Maintenance BenefitsMaintenance Benefits
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-13
Tactics forTactics for Reliability and Maintenance 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-14
System Reliability -System Reliability - Components in Series Components in Series
Average Reliability of all Components (Percent)
Relia
bility
of t
he S
yste
m (P
erce
nt)
100
80
60
40
20
0
100 99 98 97 96
n=1
n=10
n=50
n=100
n=200
n=300n=400
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-15
Reliability ofReliability of Components in Series Components in Series
R = R1 * R2 * R3 * ...
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-16
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
Evaluating MaintenanceEvaluating Maintenance
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-17
Failure Rate (%)Failure Rate (%)
Number of failures FR(%) = * 100% Number of units tested
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-18
Lifetime Failure RatesLifetime Failure Rates
Infantmortality
andimproper use
failure
“normal” failure Wearoutfailure
Failurerate
Lifetime
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-19
Failures Per Operating HourFailures Per Operating Hour
Number of Failures FR(n) = Operating Time
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-20
Mean Time Between FailuresMean Time Between Failures
1 MTBF = FR(N)
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-21
Providing RedundancyProviding Redundancy
Probability of first
component working
Probability of second component working
+
Probability of needing second component
* = P(R)
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-22
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
Maintenance DecisionsMaintenance Decisions
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-23
Preventive Breakdown
Routine inspection & servicing
Prevents failures Bases for doing
Time: Every day Usage: Every 300 pieces Inspection: Control chart
deviations
Non-routine inspection & servicing
Remedial Basis for doing
Equipment failure
Types of MaintenanceTypes of Maintenance
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-24
Mean Time Between Failure and Mean Time Between Failure and Preventive MaintenancePreventive Maintenance
Frequencyof failure
Mean Time Between Failure
Candidate for preventivemaintenance will have
distribution with lowvariability
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-25
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
Organizing theOrganizing the Maintenance Function Maintenance Function
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-26
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
Operator-Ownership ApproachOperator-Ownership Approach
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-27
A Computerized Maintenance SystemA Computerized Maintenance System
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-28
Maintenance Commitment
Cost
Preventive Maintenance CostTotTotal Maintenance Cost
Breakdown Cost
Optimal
Maintenance CostsMaintenance CostsTraditional ViewTraditional View
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-29
Maintenance CostsMaintenance CostsFull Cost ViewFull Cost View
Maintenance Commitment
Cost
Optimal
Total costs
Full cost of breakdowns
Preventive maintenance costs
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-30
Contract for Preventive Contract for Preventive MaintenanceMaintenance
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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-31
Increasing Repair Capabilities:Features Increasing Repair Capabilities:Features of A Good Maintenance Facilityof 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-32
Operations Manager Must Determine Operations Manager Must Determine How Maintenance Will be PerformedHow Maintenance Will be Performed
Operator Maintenance Department
Manufacturer’s field service
Depot Service (return equipment)
Competence is higher as we more to the rightPreventive maintenance costs
less and is faster as we move to the left
Transparency Masters to accompany Heizer/Render – Principles of Operations Management, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-33
Total Productive MaintenanceTotal 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-34
A Key To SuccessA 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, 5e, and Operations Management, 7e
© 2004 by Prentice Hall, Inc., Upper Saddle River, N.J. 0745817-35
Techniques for Establishing Techniques for Establishing Maintenance PoliciesMaintenance 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