IATF 16949 7.1.5.1.1 Measurement System Analysis (MSA - Die casting)

[Slim Pickins]

"Statistical studies shall be conducted to analyze the variation present in the results of each type of inspection, measuring, and test equipment system identified in the control plan."

I work with molten aluminum. (Die casting) We have melting and holding furnaces in which we monitor the temperature (~ 1200 - 1300 f) and have ranges called out on the control plan. They are all digital readouts and are calibrated. I received a non-conformance for not having GRR's on them. How do I do a GRR on a piece of process monitoring equipment which I cannot remove from the system and have no way of knowing a true "known" value for to try to do something in place?

Thanks in advance!

 

[Golfman25]

I would say start with a bottle of Vodka and then put your head in a vice.

Other than that, I have no clue. I think it is an overreach, but according to the letter of the law I don't think you have a prayer. It's completely frustrating. Good luck.

Is there any way you can take it "off" the control plan?

 

[Sebastian]

Measurement variation is limited only to gauge? No human impact at all?
If so, measurement system variation could be identical to measurement error determined during calibration, I think.
Calibration without removing? Interesting to know what was a master gauge then.

 

[Slim Pickins]

The system is basically a thermocouple in a bath of liquid aluminum with a digital readout on a controller which cycles the heaters on and off and alarms when out of range. No human interaction unless alarmed. Calibration is performed by applying a "simulated" temperature output from a calibration device. I could input a resistance or current that simulates a temperature and have 3 people read the numbers, but that seems like a waste of time and energy for less than zero gain.

I have already bought out the local liquor store since IATF audit. My auditor has no room for interpretation other than his. I could move it to a work instruction, but by extension it is still in the control plan; and still a process control.

 

[Golfman25]

Maybe this will help (I just skimmed it)

Calibration and R&R Practices for Temperature Measurements

 

[Sebastian]

More or less I know how thermocouple might be calibrated and it is two stage process focused on measuring and displaying portion of this system. So usually thermocouple was removed and verified in master heat chamber. Ok, so what is a measurement error of this particular thermocouple or sets of thermocouples? Did you use it as input for considering tightening of process specification?