Optimization Study Of Process Quality Inspection Plan Considering Two Types Inspection Errors

Process inspection is one of the common types of quality inspection.It is an important tool for enterprises to control product quality and monitor production process.It can provide important reference information for production process control and quality cost management.Good process inspection can sensitively identify defective products and reduce the risk of those products flowing into subsequent stages or even into downstream customers,and timely transmit information to enterprises before greater economic losses and reputation losses occur and warn enterprises to take relevant measures;On the contrary,if the company could not do process quality inspection work well,unqualified semi-finished products or parts will flow into the subsequent stages,which can directly or indirectly lead to an increase in the final product failure rate,and also increase the risk defective products flowing into customers,and lead to a negative influence on the company's economic performance and its brand reputation.Good process inspection has become an important support for enterprises to maintain their brand image and achieve ideal performance.Quality cost is an important carrier for quality inspection to affect the economic indicators of enterprises.In the process quality inspection,different quality inspection strategies and different quality inspection plans will expend different quality costs.Manufacturers always want to know which quality inspection strategy is suitable for them and which combination of those parameters for the quality inspection plan can achieve the lowest cost.In order to solve those problems,this paper establishes a process inspection quality cost model considering factors such as two types of inspection errors,and studies the relationship between each parameter in the model and the process inspection quality cost of each component.This research finds that the probability of product batch acceptance of the out-process inspection is negatively correlated with the inspection cost of the out-process inspection and the loss cost of defective products found in the out-process inspection,and is positively correlated with the potential loss cost of the defective product flowing into the subsequent stagesIn addition,this paper also studies the relationship between inspection errors,the process qualification rate and the process inspection quality cost components.This paper finds that the type II error parameter of in-process inspection is positively related to the inspection cost of in-process inspection and the loss cost of defective products found in the in-process inspection while the type I error parameter of in-process inspection is negatively related to the inspection cost of in-process inspection and the loss cost of defective products found in the in-process inspection.Additionally,this paper also finds that when the sum of two types of inspection errors of out-process inspection is greater than 1,the process failure rate is positively correlated with the inspection cost of the out-process inspection and the loss cost of defective products found in the out-process inspection,while when the sum of two types of inspection errors of out-process inspection is less than 1,the process failure rate is negatively correlated with the inspection cost of the out-process inspection and the loss cost of defective products found in the out-process inspection.Based on the process quality cost model constructed in this paper,this paper carries out the optimization research on the quality inspection plan,and discusses the optimization of the quality inspection in two cases;these two cases correspond to the practice in two occasions,it can solve the problem of quality inspection strategy optimization and optimization of inspection plan when the quality inspection strategies of in-process and out-process are uncertain,and quality inspection strategy of one of them is determined.The development of quality inspection programs provides a certain reference.