Question

1. A manufacturer wishes to sample a purchased component used in his assembly. He wishes to reject lots which are 2% defective and he receives the components in lots of 1000. He knows the supplier usually submits lots which are 1% defective or less.   The vendor has agreed to 100% inspect all rejected lots. The cost of inspecting the product is $1.50 and the cost of a defect getting into their system is $20.00. Using ANSI/ASQ Z1.4, recommend a plan.

            How would your plan change if you included the cost of the production supervisor, quality engineer, and purchasing agent? The salaries of all three are $50/hour and the problems usually take 30 minutes, 60 minutes, and 45 minutes respectively.

Answer 1

100% Inspection is time-consuming or destructive. So following up statistics rather than the fixed percentage is recommended. And generally, Normal severity and Level-2 AQL criteria are used for Inspection:

Given details are: At 2% rejection Level:

Single Sampling