2. Reduced yield-from machine startup to stable production due to the inability of the machine to operate at proper design conditions.
Maximization of .quipment .fficiency and .ffectiveness
High machine efficiency and availability can be attained by maintaining the health of the equipment. Total performance condition monitoring can play a major part here as it provides early warnings of potential failures and performance deterioration. Figure 21-1 shows the concept of a total performance condition monitoring system.
Pure preventive maintenance alone cannot eliminate breakdowns. Break-downs occur due to many factors suchas, design and or manufacturingerrors, operational errors, and wearing out of various components.Thus, changing out components at fixed intervals does not solve the problems and in some cases adds to the problem. A study at a major nuclear power station indicated that nearly 35% of the failures occurred within a month of a major turnaround. Figure 21-2 shows the life characteristics of a major piece of turbomachinery.
Figure 21-1. Total performance-based condition monitoring system. Figure 21-2. Machinery life cycle characteristics.
Category Start up Failure Chance Failure Wear Out Failure
Cause Design Manufacturing Errors Operational Errors Wear Out
Counter Measures Trial runs at acceptance and startup controls Proper Operation Preventive and Maintainability Improvement
Maintenance Prevention
The goal of any good maintenance program is "".ero Breakdown."" Toachieve this goal, there are five counter measures. These are listed below:
1. Maintaining well-regulated basic conditions (cleaning, lubricating, and bolting).
2. Adhering to proper operating procedures.
3. Total
condition monitoring (performance, mechanical, and diagnostic based).
4. Improving weaknesses in design.
5. Improving operation and maintenance skills.
The interrelationship between these five items is shown in Figure 21-3.
The division of labor between operations and maintenance is shown in Figure 21-4. It is the primary responsibility of the production department to establish and regulate basic operatingconditions, and it is the primary responsibility of the maintenance department to improve defects in design. The other tasks are shared between the two departments.
Figure 21-4. Responsibilities of the operations and maintenance departments.
The successful implementation of total productive maintenance requires:
1.
Elimination of the six big losses to improve equipment effectiveness
2.
An autonomous maintenance program with total condition monitoring
3.
A scheduled maintenance program for the maintenance department
4.
Increased skills of operations and maintenance personnel
5.
An initial equipment management program
Organization Structures for a Performance 8ased Total Productive Maintenance Program
Typically successful implementation of PTPM in a large plant takes three years. Implementation calls for:
1. Changing peoples attitudes
2. Increasing motivation
3. Increasing competency
4. Improving the work environment
The four major categories in developing a Performance Based Total Productive Maintenance program are:
1. Preparation for the PTPM program
2. Preliminary implementation
3. PTPM implementation
4. Stabilization of the program
Implementation of a Performance 8ased Total Productive Maintenance
There are several steps involved in implementation of a PTPM pro-gram.
1. Announcement of decision to implement PTPM. A formal presentationmust be made by top management introducing the concepts,goals, and benefits of PTPM. Management commitment must be made clear to all levels of the organization.
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