Exam 16: Maintenance and Reliability

What is the primary concept of total productive maintenance (TPM)? Identify the four elements that productive maintenance includes.

Twenty high-intensity bulbs are tested for 100 hours each. One failed at 80 hours; one failed at 90 hours; all others completed the test. Calculate FR(%) and FR(N).

Simulation models and expert systems are useful tools for improving total productive maintenance.

Great Southern Consultants Group's computer system has been down several times over the past few months, as shown below. Each time the system is down, the firm loses an average of $500 in time and service expenses. They are considering signing a contract for preventive maintenance. With preventive maintenance, the system would be down on average only 0.5 per month. The monthly cost of preventive maintenance would be $400 a month. Which is cheaper, breakdown or preventive maintenance?

Explain carefully how redundancy improves product reliability.

What is the impact on system reliability of adding parts or components in parallel?

________ is the failure rate early in the life of a product or process.

Why is it that many cost curves associated with maintenance rarely consider the full cost of a breakdown?

While breakdowns occur randomly, their frequency is somewhat predictable through such tools as the product failure rate, MTBF, and the breakdown costs model.

________ is the probability that a machine part or product will function properly for a specified time under stated conditions.

Which of the following is a reliability tactic?

The Everstart is a battery with an intended design life of 72 months. Stephanie Bradley recently put five of these batteries through accelerated testing (the company couldn't wait six years) to simulate failure patterns. The test results had one failure at 26 months, one failure at 32 months, one failure at 50 months, and one failure at 62 months. Calculate FR(%), FR(N), and MTBF.

At the Orlando Utilities Commission, overhauls are scheduled for summer and winter.

Why is it that many cases of infant mortality of products are not due to product failure?

Suppose that a three-stage process in a nuclear reactor had reliability ratings of .98 at each station and that only one stage needed to be successful for the process to work. If the plant wants to establish 6-sigma standards (≤ 3.4 defects per million), what % reliable redundant controls need to be added to each station?

Maintenance includes all activities involved in maintaining capability of the system.

Which of the following is NOT part of total productive maintenance?

An optimal maintenance policy strikes a balance between the costs of breakdown and preventive maintenance so that the total cost of maintenance is at a minimum.

The reliability tactics include implementing or improving preventive maintenance as well as increasing repair capabilities or speed.

Preventive maintenance implies that machine sensors to detect variations from normal are inadequate.