IATF 16949 Cl. 7.1.5.2.1 - Gauges (Measuring Jigs) Calibration/Verification Records

[joe visava]

In 7.1.5.2.1 calibration / verification records: Are all gauges(measuring jigs) in manufacturing calibrated or verified?
What is criteria of calibration or verification for each guage(measuring jig)?

 

[Rich Shippy]

Re: IATF 16949 Cl. 7.1.5.2.1 - Gauges (Measuring Jigs) Calibration/Verification Recor

I would suspect every dimension and tolerance that gage measures, has to be verified . Typically these are done by an accredited internal or external source, and calibration certificates retained as records.

 

[Marc]

Re: IATF 16949 Cl. 7.1.5.2.1 - Gauges (Measuring Jigs) Calibration/Verification Recor

In 7.1.5.2.1 calibration / verification records: Are all gauges(measuring jigs) in manufacturing calibrated or verified?
What is criteria of calibration or verification for each guage (measuring jig)?

It will be like any other measurement device used for acceptance, whether in-process or final inspection. It should be in your calibration database with a scheduled frequency, etc.

You may call it a "jig", but it is a measurement device.

 

[QChas]

Re: IATF 16949 Cl. 7.1.5.2.1 - Gauges (Measuring Jigs) Calibration/Verification Recor

We do this with numerous jobs. Steps are as follows:
1) Create a drawing for the gauge identify what dimensions need checked (Jig)
2) Assign an ID to the gauge (for example Jig-123)
3) Check dimensions with calibrated gauges. Be sure to reference gauges used
4) Put in you calibration database with calibration interval
5)In our case each year check the gauge, document results, new due date

 

[Ron Rompen]

Re: IATF 16949 Cl. 7.1.5.2.1 - Gauges (Measuring Jigs) Calibration/Verification Recor

Just to add one more item to QChas's response, ensure that the gauges you use to VALIDATE/CALIBRATE your 'jigs' are also properly calibrated, and that the calibration is traceable to the appropriate national standard.

 

[GilesBee]

Re: IATF 16949 Cl. 7.1.5.2.1 - Gauges (Measuring Jigs) Calibration/Verification Recor

Hi,

I got an NCN in my transition audit in 7.1.5.2.1 for
The organization shall ensure that calibration/verification activities and records shall include the following details:
.
.
.
f) statements of conformity to specification after calibration/verification;
ie we had no process for accepting a gauge after calibration. Our auditor stated that if measurement uncertainty is quoted on a calibration certificate then this should be used to determine whether the gauge is still suitable for use. Does anyone know if there are any rules / calculations that can be used for this? All help gratefully received

 

[dwperron]

Re: IATF 16949 Cl. 7.1.5.2.1 - Gauges (Measuring Jigs) Calibration/Verification Recor

Looking at this I would say that two issues are being confused here.

7.1.5.2.1.f) is a requirement that the calibration record states conformity to the specification (in or out of tolerance) after calibration. I am pretty sure your calibration certificates include that.

As for how to handle the measurement uncertainty in determining the conformity, that is what is called a "decision rule". ISO 17025 covers that calibrations for IATF 16949, and that states in 5.10.4.2:

"When statements of compliance are made, the uncertainty of measurement shall be taken into account."

Therefore, the calibration determination of in / out of tolerance should already take measurement uncertainty into account by the calibration lab.

Concerning whether or not the gauge is suitable for use, that would be better covered in IATF 16949 7.1.5.1.a):

"The organization shall ensure that the resources provided:
a) are suitable for the specific type of monitoring and measurement activities being undertaken"

Therefore when a tool is chosen for a particular measurement the measurement uncertainty of the calibration must be accounted for to assure the tool is "suitable". In most cases the measurement uncertainty is small and will not be a significant contributor. In some cases it can be very significant. Here is an example:

A digital caliper is used in measuring a test jig. The tolerance for the measurement is 10.000 ±0.005 in. You use a caliper with 0.001 resolution, thinking it should be good enough. The specification for the caliper is ±0.002 in, and the measurement uncertainty on the certificate is 710 µin (or 0.00071 in). You need to add the uncertainty to the tolerance so the uncertainty is "taken into account" (± 0.00271 in), and thus determine if the tool is "suitable for use".

A challenge in complying with this finding is determining what your organization's rule is for "suitable for use" (a 4:1 or a 10:1 ratio rule is typical). It needs to include the measurement uncertainty to be valid.