Optimal Design of Reliability Acceptance Sampling Plans for Multi-stage Production Process

One of the goals in manufacturing industry is to follow manufacturing standards which ensure that the manufactured products meet expectations of consumers. An Acceptance sampling plan is a tool to ensure that quality of products meet the minimum expected standards. In this chapter, an attempt is made to derive lot acceptance single and double sampling plans based on type ii censored data. The units in the lot have multiple quality characteristics and are processed through multi-stage process. We assume that the quality characteristics of units follow the exponential distribution. The acceptance criterion for the given lot is derived based on mean-life of units in the sample at every stage. Further, two non-linear optimization problems, which minimize the expected total testing cost at the acceptable quality level, are solved. In addition, sensitivity analysis studies are also conducted to assess the behavior of total testing costs with respect to change in producer’s and consumer’s risks and sample sizes. Several numerical examples and two case studies are presented to illustrate our resulting sampling plans.