During this step, we study the drawings, standards, and actual equipment and materials intending to identify the 4-M conditions (relating to materials, machinery, methods, and checks) under which the defect modes in each of the individual steps in the QA matrix would not occur. As Table “Example of QA Matrix” illustrates, we identify the conditions that must be observed for no defects to be produced and work out where they are deficient by assessing whether there are clear standards for them, whether these standards are being followed, and whether any necessary standards have been omitted. It is generally found that required conditions and/or standards have not been specified at all or are unclear and are left to the subjective judgement of the operators who are supposed to implement them.
4-M analyses of defect modes of medium process feeds indicate that many X, Y and Z instances occur in machinery and methods (people), so solutions to abnormalities are needed in these areas.
4M Analysis Process
The purpose of this procedure is to define the steps to do a 4M …
