Practical Reliability Engineering, 5th Edition

12

Reliability Testing

12.1 Introduction

Testing is an essential part of any engineering development programme. If the development risks are high the test programme becomes a major component of the overall development effort, in terms of time and other resources. For example, a new type of hydraulic pump or a new model of a video recording system will normally undergo exhaustive tests to determine that the design is reliable under the expected operating environments and for the expected operating life. Reliability testing is necessary because designs are seldom perfect and because designers cannot usually be aware of, or be able to analyse, all the likely causes of failure of their designs in service. The disciplines described in earlier chapters, when systematically applied, can contribute to a large extent to inherently reliable design. They can also result in fewer failures during testing, and thus reduce the time and cost of the test programme.

Reliability testing should be considered as part of an integrated test programme, which should include:

1. Functional testing, to confirm that the design meets the basic performance requirements.
2. Environmental testing, to ensure that the design is capable of operating under the expected range of environments.
3. Statistical tests, as described in Chapter 11, to optimize the design of the product and the production processes.
4. Reliability testing, to ensure (as far as is practicable) that the product will operate without failure during its ...