MSA's are not my specialty. But my first instinct would be to take a series of readings using a torque calibrator (one of the digital types with a peak indicator). Follow normal MSA methodology, using the same person for a series of readings, then different people and different shifts (as applicable).
It must be understood that the MSA is on the torque wrench. To understand how repeatable the torque wrench is, MSA must be done via a method that verifies what you tighten in ft-lbs or whatever other force unit is used is tightened repeatably to within acceptable variability. This can only be done by measurement of what the torque wrench has done. The only method I am familiar with is via a torque calibrator.
If you don't have a torque calibrator, there needs to be some method of "reading" the breakover point with something of appropriately higher stability than the torque wrench. It is also necessary that either the torque wrench be sealed at a setting (ONLY if it is used that way), or that the wrench be backed down to zero, and re-tightened to the torque setting at each iteration. If the torque wrench is always used at one setting only, and is left in that setting, leave it. If the torque wrench is used at a variety of settings, use a standard methodology for how the wrench is set up for the specific torque of the MSA, and repeat that exact methodology at each iteration.
If you don't have a torque calibrator, perhaps you could rent a calibrated unit for a few weeks for the MSA, contract a calibration subcontractor to do it for you, or pay a calibration subcontractor for time in their lab using their torque calibrator under their supervision.
The one other suggestion would be to see if the manufacturer has any data on R&R for the particular torque wrench (only if you can't derive the data yourself).
Another question I would have if I were in the situation would be to verify as to whether the torque wrench truly did or did not need an MSA. MSA's are normally done on measurements or controls to process that could impact products ability to meet it's claimed specs. The MSA gives a confidence as to whether or not the product meets that spec. I am sure it is conceivable that torque of a screw could have impact on a product spec. But there are also plenty of other potential areas where a calibrated torque wrench is used on a product, but does not truly impact product specs. I truly don't know which category this falls into. But I would certainly ask the question as to whether or not it is a requirement in the particular case.
PLEASE -- don't take that as a recommendation either way. Only to ask the right questions to determine whether or not it is a legitimate requirement. I have seen many cases over the years where companies calibrate everything in sight because that is an apparently simpler path than justifying on an individual basis whether there is a need or not.
I'm not sure how much help this is. Hopefully it will at least give some food for thought.
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It must be understood that the MSA is on the torque wrench. To understand how repeatable the torque wrench is, MSA must be done via a method that verifies what you tighten in ft-lbs or whatever other force unit is used is tightened repeatably to within acceptable variability. This can only be done by measurement of what the torque wrench has done. The only method I am familiar with is via a torque calibrator.
If you don't have a torque calibrator, there needs to be some method of "reading" the breakover point with something of appropriately higher stability than the torque wrench. It is also necessary that either the torque wrench be sealed at a setting (ONLY if it is used that way), or that the wrench be backed down to zero, and re-tightened to the torque setting at each iteration. If the torque wrench is always used at one setting only, and is left in that setting, leave it. If the torque wrench is used at a variety of settings, use a standard methodology for how the wrench is set up for the specific torque of the MSA, and repeat that exact methodology at each iteration.
If you don't have a torque calibrator, perhaps you could rent a calibrated unit for a few weeks for the MSA, contract a calibration subcontractor to do it for you, or pay a calibration subcontractor for time in their lab using their torque calibrator under their supervision.
The one other suggestion would be to see if the manufacturer has any data on R&R for the particular torque wrench (only if you can't derive the data yourself).
Another question I would have if I were in the situation would be to verify as to whether the torque wrench truly did or did not need an MSA. MSA's are normally done on measurements or controls to process that could impact products ability to meet it's claimed specs. The MSA gives a confidence as to whether or not the product meets that spec. I am sure it is conceivable that torque of a screw could have impact on a product spec. But there are also plenty of other potential areas where a calibrated torque wrench is used on a product, but does not truly impact product specs. I truly don't know which category this falls into. But I would certainly ask the question as to whether or not it is a requirement in the particular case.
PLEASE -- don't take that as a recommendation either way. Only to ask the right questions to determine whether or not it is a legitimate requirement. I have seen many cases over the years where companies calibrate everything in sight because that is an apparently simpler path than justifying on an individual basis whether there is a need or not.
I'm not sure how much help this is. Hopefully it will at least give some food for thought.
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