R
Robert O'Brien
I have conflicting references on the formula for calculating part variation (PV) on a gage R&R study. The formula given in the CQE handbook is as follows:
PV = grand average range/d2
Grand average is obviously the average range among all appraisers and d2 (which I’m slightly confused by) is from the constants for control charts table. Is this correct?
My second conflicting resource is as follows:
PV = grand average range x K3
I’m not sure where K3 comes from. I’m guessing it is obtained from the MSA manual, which unfortunately I do not have.
Can anyone provide me some insight on the correct formula for calculating PV?
Best regards,
Rob O'Brien
PV = grand average range/d2
Grand average is obviously the average range among all appraisers and d2 (which I’m slightly confused by) is from the constants for control charts table. Is this correct?
My second conflicting resource is as follows:
PV = grand average range x K3
I’m not sure where K3 comes from. I’m guessing it is obtained from the MSA manual, which unfortunately I do not have.
Can anyone provide me some insight on the correct formula for calculating PV?
Best regards,
Rob O'Brien