The integrated application of acceptance sampling in the quality control of manufacturing process and quality assurance of shipment product

Abstract

In this work, the authors propose the integrated application of CSP-1 plan and Dodge-Romig rectifying inspection plan with expected inspection cost, expected replacement cost, expected warranty cost, expected quality loss for conforming product, and expected quality loss for non-conforming product per item. The quality characteristics of product is considered as the normal distribution with nominal-the-best and symmetric quadratic quality loss function.

The CSP-1 plan is firstly applied in the process control. The optimal combination of parameters is obtained from the minimum expected total cost per item produced under the specified average outgoing quality limit (AOQL) protection. One needs to have the optimal clearance number, sampling frequency, and specification limit coefficient. Then Dodge-Romig rectifying inspection plan is applied in the product improvement. The optimal sample size, clearance number, and quality investment are obtained by minimizing the expected total cost per lot under the specified consumer’s risk.

Subject Classification: (2010):

• 60 Probability theory and Stochastic processes

Keywords:

• Type I continuous sampling plan (CSP-1 plan)
• Dodge-romig rectifying inspection plan
• Average outgoing quality limit (AOQL)
• Consumer’s risk
• Quadratic quality loss function
• Specification limit coefficient
• Quality investment