In order to effectively manage variation of any process and The Measurement Process, there needs to be knowledge of:
What the process should be doing
What can go wrong
What the process is doing
Specifications and engineering requirements define what the process should be doing.
The purpose of a Process Failure Mode Effects Analysis of the (PFMEA) is to define the risk associated with potential process failures and to propose corrective action before these failures can occur. The outcome of the PFMEA is transferred to the control plan.
Knowledge is gained of what the process is doing by evaluating the parameters or results of the process. This activity, often called inspection, is the act of examining process parameters, in-process parts, assembled subsystems, or complete end products with the aid of suitable standards and measuring devices which enable the observer to confirm or deny the premise that the process is operating in a stable manner with acceptable variation to a customer designated target. But this examination activity is itself a process.
Knowledge is gained of what the process is doing by evaluating the parameters or results of the process. This activity, often called inspection, is the act of examining process parameters, in-process parts, assembled subsystems, or complete end products with the aid of suitable standards and measuring devices which enable the observer to confirm or deny the premise that the process is operating in a stable manner with acceptable variation to a customer designated target. But this examination activity is itself a proce.
Unfortunately, industry has traditionally viewed the measurement and analysis activity as a “black box”. Equipment was the major focus – the more “important” the characteristic, the more expensive the gage. The usefulness of the instrument, its compatibility with the process and environment, and its usability was rarely questioned. Consequently these gages were often not used properly or simply not used.
The measurement and analysis activity is a process – a measurement process. Any and all of the management, statistical, and logical techniques of process control can be applied to it.
This means that the customers and their needs must first be identified. The customer, the owner of the process, wants to make a correct decision with minimum effort. Management must provide the resources to purchase equipment which is necessary and sufficient to do this. But purchasing the best or the latest measurement technology will not necessarily guarantee correct production process control decisions.
Equipment is only one part of the measurement process. The owner of the process must know how to correctly use this equipment and how to analyze and interpret the results. Management must therefore also provide clear operational definitions and standards as well as training and support. The owner of the process has, in turn, the obligation to monitor and control the measurement process to assure stable and correct results which includes a total measurement systems analysis perspective – the study of the gage,procedure, user, and environment; i.e., normal operating conditions.
source : Analysis of measurement systems
