Maintenance System Performance, Productivity, and Continuous Improvement

Abstract

Productivity and continues improvement of maintenance systems is the subject of this chapter. Continuous improvement of maintenance systems may be achieved using three approaches. The first approach is to use performance measures and the second approach is to conduct periodic auditing of the maintenance system. The third approach is to combine both approaches. In the first approach performance measures for the maintenance system are defined and computed on periodic basis. Targets are set and based on the system performance and the targets improvement programs are developed and implemented. In the second approach the regular audits are used to identify areas to improve the system. In this chapter a set of input, output and within the system measures together with the balanced scorecard are presented. Maintenance indices for administration, effectiveness, and cost followed by metric comparisons are provided. Then the chapter focuses on maintenance auditing and root causes analysis for developing corrective and preventive actions that is expected to result in continuous improvement. The chapter is concluded by a case study on maintenance, followed by benchmarking techniques.

Exercises

• 1. Define the term mean time between failures (MTBF) and suggest two ways of computing it.

• 2. A steel plant was scheduled to operate for 330 days last year. It had 8 unscheduled breakdowns that resulted in 240 h of downtime. The plant had 96 h of preventive maintenance during these 330 days. The plant was shutdown for 120 h due to lack of feed. Process was slow for 60 h at 80 % rate and wet feed slowed the process also for 48 h at 50 % rate.

  The production rate at 100 % capacity is 1000 tons per 24 h. In this period, 3000 tons was rejected and 5000 tons was classified as a second-quality product and sold at 50 % value.

  • (a) Compute the plant availability , A.

  • (b) Compute the process rate, PR.

  • (c) Compute the quality rate, QR.

  • (d) Compute overall equipment effectiveness (OEE) .

  • (e) Compute the productivity capacity.

  In order to improve the productivity capacity which factor should management focus on and why?

• 3. List the factors that constitute the maintenance scheme .

• 4. List the most important three factors in the audit scheme. Justify your answer.

• 5. Use the analytic hierarchy process (AHP) to estimate the weight of each factor listed in Question 1.

• 6. Why ABC analysis is needed in the continuous improvement program?

• 7. List possible corrective actions for the factor engineering and condition monitoring, if found deficient from the audit program.

• 8. Locate an organization nearby, conduct a detailed audit program, and use the approach suggested in the plan given in this chapter to suggest improvements.