PLANNING QUALITY INSPECTION OPERATIONS IN MULTISTAGE MANUFACTURING SYSTEMS WITH INSPECTION ERRORS

The management of resources dedicated for the appraisal of critical pr oduct quality attributes is a matter of increasing importance in multi stage manufacturing systems. An interesting quality planning problem l ies in the operational implementation of a quality inspection policy t o select specific locations and machines for inspection activities. In this research, a mathematical model is developed for solving the insp ection allocation and assignment problems in a multistage manufacturin g system. The multistage system here considered processes part types w ith distinctive machine visitation sequences, and inspections can be p erformed on one of the several inspection stations with possible inspe ction errors. The computational process shows that as the problem size increases the number of inspection allocation possibilities and the c omputer system memory required becomes prohibitively large. Thus, thre e heuristic solution methods have been developed and are found to be e ffective in arriving at a near optimal solution with considerable savi ngs in computational effort when compared with the optimization method based on complete enumeration. The heuristic solution methods are fur ther compared with each other to determine their relative strength and weakness. A computer simulation is conducted to evaluate the methods developed.