Process Control Methods FAQ

Process Control Methods

Process Control Methods Subject Matter Interest Group

Process Control Methods Subject Matter Interest Group Frequently Asked Questions



Do I have to use the Scoring Guidelines in RM13006 if we have our own scoring guidelines established over many years?  No, provided that the customer has accepted that the criteria that you are using is acceptable to them then it is acceptable to use your own. 
What does any feature classified as a “Key Characteristic (KC)” require relative to process control?  Always understand directly what your Customer requires.  As far as AS13100, a KC is a feature classified as such as it can potentially impact any of the following: Form, fit, function, safety, performance, reliability and service life.  Therefore, it is important to account for KC’s in the Product Flow Diagram, PFMEA and Control Plan per RM13004.  RM13006 defines nine specific process control methods.  For KC’s, the common control method is the use of Variable Control Charts when the KC is a variable feature.  This would require a Gage Repeatability & Reproducibility Study for the measurement system used to evaluate the KC.  RM13006 also describes the use of Attribute Control Chart methods for attribute features, not as commonly used.  It is recommended when controlling a KC using non-statistically based methods described in RM13006 that the user first complete a process capability study with at least 25-30 measurements along with a Control Chart.  The control chart will allow the producer to see the time ordered consistency of the process while the process capability analysis (i.e., Cp & Cpk) will evaluate the ability of the process to meet the engineering specification 100% of the time.