4.7 What is Product Control?
As a definition:
Product control involves the control of products at the source of production and through field service so that departures from the quality specification can be corrected before defective or nonconforming products are manufactured and the proper service can be maintained in the field to assure full provision of the intended customer quality.
There are three phases in product control
1. Control of machining or processing of components
2. Control of assemblies and packaging of batches
3. Control of customer product service
Techniques used in product control include implementation of a complete quality plan for in-process quality control and final product acceptance; process-capability studies; process sampling: nondestructive testing: control chart technique; tool, jig, and fixture control; calibration of quality information equipment; quality audit: operator instructions and training, analysis of com- plaints; and analysis of quality costs for their optimization and field service quality techniques. Product control is treated in detail in Chapter 20.