Attribute Gage R&R MSA (Measurement Systems Analysis) on Pin Gages

J

joptak

MSA on Pin Gages

Hi Everyone,

TS 7.6.1 says "Statistical studies shall be conducted to analyse the variation present in the results of each type of measuring and test equipment system. This requirement shall apply to measurement systems referenced in the control plan".

We reference go/no-go pin gages on our control plans but currently do not perform any kind of MSA activity on these types of gages aside from the occaisonal attribute study during PPAP. We are TS certified but our auditors have not directly questioned us on pin gages because most of our control plans previously referenced micrometers. In an effort to improve the relationship between our control plans, inspection sheets, and actual inspection techniques, we've made the switch to referencing pin gages on our control plans. I'm curious as to how others have handled pin gages in regards to MSA and what questions auditors have posed regarding pin gages and MSA.

Any guidance, advice, or suggestions would be greatly appreciated.

Thanks,
Joe.
 

Geoff Cotton

Quite Involved in Discussions
Re: MSA on Pin Gages

Joptak,

We carry out simple attribute GR&R studies to a schedule on our pin gauges, never had a problem from an audit point of view.
 
J

joptak

Re: MSA on Pin Gages

Hi Geoff,

Thanks for the reply. Do you do attribute studies on all your pin gages? If not, what's the critiera for being "study-worthy". Also, at what frequency do you conduct these studies? If you did a study this month, when would the next study be performed on that gage?

Thanks,
Joe.
 

Geoff Cotton

Quite Involved in Discussions
Re: MSA on Pin Gages

We do not have too many pin gauges these days but in years gone by we used to have hundreds. Reviewing the results of the previouse studies we concluded that there were no major issues and now only carry out a study on a yearly basis.

Not every pin guage is studied, we do a random selection of one or two guages but avoid selecting from the same manufacturing location where we can, of course we eventually go full circle back to the start location.

What we do insist on is that every new starter is put through the MSA procedure and studied usingthe guages nominated on their control plan(s). This is done as part of their induction program.
 

The Taz!

Quite Involved in Discussions
Re: MSA on Pin Gages

Hey gang,

Attribute gage studies are acceptable for pin gages (AIAG MSA Manual). We only did the MSA studies for attribute gages called out on Control Plans. This way we satisfy using the gages in the application for which they are specified. . . parts, operators, environment. . etc.

IMHO, Yearly calibration is usually sufficient but beware of tight parts wearing the pin gages. This should be considered and a reasonable frequency established.

Our usual practice was to narrow limit the gaging specs. so that we would not reach the tolerance limit in production. Full gage spec. was used as a referee for final acceptance.

Hope this is of some help.
 
B

Bill Ryan - 2007

Re: MSA on Pin Gages

We are a small/medium die cast / machine / light assembly facility (2 buildings). We have, literally, hundreds of pin/plug gages in use. We take five pins per year and perform the short attribute gage R&R (we are going to move it out to two years in the near future, I believe). These five pins span the range of pin sizes we have. These studies are what we include in PPAP submissions.

Typically, we use pins for holes/cores/slots that have +/-.005" tolerances, minimum (a couple of parts may have +/-.003"). As long as the pin is calibrated (each one!!), and the operator trained, I'm not too concerned with an R&R on each pin. However, if my customers would begin changing their minds and drawing the "line in the sand" stating each gage SHALL have an R&R, I'm sure they would be willing to pay for the, in my mind, non-value added activity :vfunny: .

BTW - Welcome :bigwave: and good question!

Bill
 
T

Tulman

Gauge R&R

Bill Ryan said:
However, if my customers would begin changing their minds and drawing the "line in the sand" stating each gage SHALL have an R&R, I'm sure they would be willing to pay for the, in my mind, non-value added activity :vfunny: .

BTW - Welcome :bigwave: and good question!

Bill

I work for a automotive component manufacturing company and more and more customers are requiring that EACH gauge for critical char. identified either by the customer or the suppler SHALL have a MSA. During our upgrade to TS we had a finding for this from Borg and Ford CSR (customer specific requirements).
 
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Dave Dunn

In regards to pins being used for dimensional measurement, I would consider the complete set your "gage". What you're really doing is GR&R on the measurement system, which includes the part dimension, operator, and gage. Just as you would not do GR&R on each possible digit of resolution of a micrometer, you wouldn't do GR&R on each individual pin.

What this does mean though, is that every part and dimension that requires MSA must have its own GR&R. If you have multiple parts or diameters that are critical and require MSA, you need to do GR&R for each part and diameter. I don't believe you can just perform a GR&R study on a generic feature and part and call it a GR&R for gage pins and thereafter use it to validate similar measurement systems. A different part or different feature creates a different measurement system, which needs to be evaluated on its own.
 
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