The fill time is not expected to vary much form shot to shot. Typically, large variations indicate a parameter change or a change in machine performance.
Question: We are using fill time as one of the process outputs for monitoring the process consistency. There is hardly any change which is showing variations. My Question is it a right approach to monitor the fill time data with variation of only + 0.04 seconds.
My Response: The lack of variation implies accurately functioning machinery. The purpose of monitoring fill time is to indicate a significant change. This might be a machine variation, pressure limited process, or a parameter change that affects 1st Stage Injection. Typically limits of + 0.5% will identify such changes when they occur.