The Process capability index rule type monitors the stability of a process. The rule type calculates the C pk of normally distributed data. An event is triggered if the calculated C pk violates the configured limits of the Cpk.
The process capability index is calculated as follows:
The values are distributed normally.
Example
The quality tolerance of a rotation is used to define the upper and lower specification limits.
If the observed Cpk value is less than the configured Cpk value, an event is triggered. The C pk value drops when the diameter values fluctuate.
