Date: Wed, 31 May 2000 13:34:59 -0400
Subject: GAGE STABILITY AND LINEARITY
I have been requested by our QS9000 registrar to begin performing Gage Stablility and Linearity Studies. I have performed Gage R&R studies but never linearity or stability studies. Can anyone give me some detailed information on what type of data collection is needed to perform these studies and how to perform these studies? I have software (Gagetrak 4.0) for analyzing the data but it doesn't really specify exactly how and what type of data is needed.
Thank you.
Date: Mon, 5 Jun 2000 07:10:35 -0400
Subject: Re: GAGE STABILITY AND LINEARITY
Gage Linearity studies are performed by calibrating a series of points over the entire operating range of the M&TE (measuring and test equipment). You can then determine if the bias error is linear, or not, and whether the M&TE is in calibration across its entire range, or not.
Gage Stability studies involve an overtime comparison of the bias results. The simplest construct is to calibrate the same points each time. Then over time you can see if there are trends, etc. When you have enough points, you can calculate a control chart and determine if your M&TE is in control or not, statistically. Gage stability studies assist in determining calibration intervals, since you can see historically how long the piece of M&TE remained in calibration and predict when it will go out.
Date: Fri, 09 Jun 2000 09:08:32 -0400
Subject: Re:GAGE STABILITY AND LINEARITY re1
So does this mean I can use actual calibration data from gage block measurements I've performed for past calibrations for both linearity and stability? I' just confused on what kind of actual data I need to use.
Date: Sun, 11 Jun 2000 19:17:35 -0400
Subject: Re: GAGE STABILITY AND LINEARITY
Yes. Stability requires over time data, so past data is fine. For linearity, you typically use current data, and past data could be used as another stability check.