R
rderoeck - 2006
Can somone explain to me what the P/t ratio (Precision/Tolerance) =RR/(USL-LSL) tells me about my gage study? Is there some magic number that needs to be met?
Thanks,
Rich DeRoeck
Thanks,
Rich DeRoeck
Welcome to the Coverderoeck said:Can somone explain to me what the P/t ratio (Precision/Tolerance) =RR/(USL-LSL) tells me about my gage study? Is there some magic number that needs to be met?
Thanks,
Rich DeRoeck
Well, more precisely, it's a different way of looking at it that takes the 3-sigma magnitude of R&R into consideration.rderoeck said:So......this is diferent than the % R&R requirement of <10%. Do I have this right?
Rich
rderoeck said:Someone showed me a GRR study using JMP software. It printed out the following summary:
10.3334 % Gage R&R=100*(RR/TV)
0.16857 Precision/Tolerance Ratio=RR/(USL-LSL)
So the first one is comparing the percentage of measurement variance to process variance (as determined by the study data) while the second one is comparing the proportion of measurement error to the part tolerance.
Can you then say that the percentage of P/t is 16.857%?