1 Maintenance Management

2 Equipment Malfunctions l Equipment malfunctions have a direct impact on: l Production capacity l Production costs l Product and service quality l Employee or customer safety l Customer satisfaction

3 Maintenance Departments l A maintenance manager typically is a plant engineer who reports to a plant or manufacturing manager l Maintenance departments are usually split into two groups: l Buildings and Grounds l Equipment

4 Maintenance Activities l Repairs l Repair activities are reactive. l Breakdowns and malfunctions typically occur when equipment is in use. l Standby machines and parts can speed repairs. l Preventive Maintenance (PM) l Regularly scheduled inspections are performed. l PM activities are performed before equipment fails. l PM is usually performed during idle periods.

5 Tradeoff Between Repairs and PM l At minimum level of PM, it is a remedial policy l fix machines only when they break l the cost of breakdowns, interruptions to production, and repairs is high l As the PM effort is increased, breakdown and repair cost is reduced l At some point, the total maintenance cost (PM, breakdown, and repair) reach a minimum

6 Tradeoff Between Repairs and PM Annual Cost ($) Degree of Preventive Maintenance Minimum Total Maintenance Cost PreventiveMaintenanceCost Breakdown and Repair Cost TotalMaintenanceCosts Minimum Level of PreventiveMaintenance

7 Reduces Reduces Reduces Reduces Maintenance Policy Frequency Severity Emphasize preventive maintenance XX Provide extra machines X Replace machine parts early X Involve operators in maintenance XX Overdesign machines X Design machines for maintainability X Enhance maint. dept.’s capability XX Increase spare parts supply X Increase standby machines X Increase in-process inventories X Maintenance Policies that Reduce Frequency and Severity of Malfunctions

8 Repair Programs l Objectives l Get equipment back into operation as quickly as possible. l Control cost of repairs crews. l Control cost of the operation of repair shops. l Control the investment in replacement spare parts. l Control the investment in standby or backup machines. l Perform the appropriate amount of repairs at each malfunction.

9 How Speedy Should Repairs Be? Cost ($) Speed of Making Repairs 0 Minimum Total Cost of Repairs Cost of Repair Crews & Shops, Spare Parts, and Standby Machines Cost of Interruptions to Interruptions toProduction Total Costs of Repairs SlowFast

10 Breakdowns Trigger Repairs and Corrective Actions An equipment breakdown should trigger two actions: l Fast repair of the malfunction equipment l Development of a program to eliminate cause of the malfunction and need for such repairs in the future l Modification/redesign of malfunctioning machine l Modification/redesign of part or product being processed l Training of operators to improve machine care l More frequent preventive maintenance/inspection

11 Extent of Repairs l Do just enough repairs to get equipment running again. l Repair the malfunction and replace some parts that are worn. l Perform a major overhaul of the equipment. l Replace the old equipment with new.

12 Decision Analysis in Repair Programs l Determining the size of repair crews l This is one repair-capacity decision l Queuing analysis is often used l Computer simulation is used when the assumptions of queuing formulas do not apply l Determining the number of standby machines to have l Trade-off between cost of lost production time and cost of machine storage, handling, ….

13 Reasons for a PM Program l Reduce the frequency and severity of interruptions due to malfunctions l Extend the useful life of equipment l Reduce the total cost of maintenance by substituting PM costs for repair costs l Provide a safe working environment l Improve product quality by keeping equipment in proper adjustment

14 PM and Operations Strategies l PM program is essential to the success of a product- focused positioning strategy l On production lines, there are little if any in-process inventories between adjacent operations l If a machine breaks down, all downstream operations will soon run out of parts to work on

15 Secondary Maintenance Responsibilities l Housekeeping, groundskeeping, janitorial l New construction, remodeling l Painting l Security, loss prevention l Pollution control l Waste recycling l Safety equipment maintenance l Public hazard control

16 Trends in Maintenance l Production machinery is becoming more and more complex and maintenance personnel must keep pace l Special training programs to maintain worker skill level l Subcontracting service companies l Production workers maintain own equipment l Computer assistance in maintenance

17 Maintenance Issues in Service Organizations l Maintenance issues are not limited to manufacturing l Transportation firms (airlines, trucking companies, package delivery services, railroads) must keep their vehicles in top operating condition l Highway departments must maintain roadways l Office personnel are reliant on copiers, printers, computers, and fax machines working properly l As services become increasingly automated, service firms face more and more maintenance issues

18 Wrap-Up: World-Class Practice l Empower workers so they “own” their machines l Implement JIT to help reduce inventories and cycle time l Invest in factory and service automation projects l Utilize automated process sensing and control systems l Use computers in maintenance management