Inspections and Assembiels When two negative effects turn positive

Abstract

Abstract-No process is perfect and defective items are produced in any process, but in commercial operations there are sales targets and/or orders to deliver. Therefore, a very basic rule is the compensation principle: a compensating unit must be produced for any defective unit. A common method for coping with defective items is to perform cleaning -inspect the items and remove defective units. Inspections however are error prone and the destructive effect of false rejections in serial processes is presented. In assemblies, there are mutual relationships among the components and the yield -the ratio of the number of conforming units to the total number of units diminishes very rapidly in the presence of defective components. Yet, it turns out that cleaning of defective assembly components prior to the assembly, improves quality and reduces waste simultaneously.