Difference between Test Method Validation and Gage R&R

[deepikanegi]

Hello ALL,

What is the difference between Test Method Validation and Gage R&R?

 

[William55401]

TMV is a broader term where GRR is a specific method to show a measurement method is effective. HTH.

 

[deepikanegi]

Thanks for quick response. Could you please explain with an example?

 

[Ninja]

Test Method Validation is a broader term.
Some ways of performing a Test Method Validation include (but is not limited to):
- GR&R
- Customer approval
- ASTM directed test with quantified, verified output

In short, GR&R is one method of TMV...but not the only one available.
FWIW, GR&R is by far the most commonly and easily accepted one in my experience.

 

[William55401]

Another example. Attribute TMV involves challenging a test method with known bad units. Does it detect them? I don't consider this a pure GRR approach. One more. Don't get so wrapped up in labeling something (GRR vs TMV for example). Spend more time thinking about how to demonstrate a particular method is effective.

 

[Frypot]

I have been asked by a customer to validate our test method for seal strength (as in ASTM F88) I have no 'known value' standards, the customer also wants me to compare the method at two different sites (i.e. two different tensile machines) I can produce plenty of samples for testing though they have quite a lot of variability due to the materials (grid lacquer paper as a 4SS pouch).
Any suggestions?

 

[Ninja]

Howdy,
Typically a tensile tester "known value" is just calibrating the load cell.
I know of no "known value" destructive standards for this type of test...

If it helps, you can send out some samples to an outsource lab, then compare sample means to show that your equipment is giving nominally similar values. If your customer also does this test...you may have more overall benefit sending to them, and thus correlating your sites with the customer as well (and it would be free).
HTH

 

[chris1price]

I know this is a bit short notice...... but Westpak, a specialist packaging test lab have a webinar on Test Method Validation for packaging on 1st April. It might be worth attending.

https://www.westpak.com/resources/webinars/?nonitro=1

No connection, but I have used them in the past.

 

[Frypot]

Well so far what I've done is to use a t-test on ~ 50samples to get a measure of repeatability the had another 50 samples tested on our other site, done a t-test to tick the reproducable box. Hopefull the customer will be happy with it, the machines are, calibrated externally and within calibration period.
Thanks for the responses!

 

[Bev D]

A t-test cannot give you information on repeatability.