Calibration Label issues

[dwperron]

"So for most of us, why be concerned about growth?"

Maybe this doesn't apply to "most", especially if your tolerances are in the thousandths.
But for those of us operating at higher precisions - microinches - it can bring gauges out of tolerance.
We also see the growth of pin and plug gauges occur after they age, and it is fascinating to see how multiple pins in a set will "grow" at the same time.

 

[BradM]

Good morning!!

Your first post was incredibly detailed and well laid out. It makes for a much more interesting discussion.

I faced a similar situation. Techs in a hurry or whatever, and we had sticker problems.

Question... do you happen to know the main cause of these sticker failures? You have... a label/ sticker missing, and/or an improperly completed sticker. By what you indicated (some kind of punch-out sticker...I like that idea by the way), I mean... is it too easy to make a mistake with them? Is June/July way too close together on the sticker?

Have you been able to have a decent conversation with the techs? I know... this is hard. They may feel you're accusing them of failure or whatever. But maybe they have a hard time punching the things out.

Do they know precisely where (calibration sheet, database, whatever, the exact line) to get the date to punch out?

The mfg. of the labels... have you asked them if their other customers have problems?

Do the techs feel so rushed and overwhelmed they get in too big of a hurry and make mistakes completing the labels?

I'm just assuming by what you have typed... you're gonna have to use calibration labels for a while. So I would buy some folks some pizza and drinks at lunch, tell them you really need their help, and dig in and try to find out why this is occurring.

 

[Scanton]

You should come visit my lab and see how we have gauges - pins, plugs, and rings especially, that change size without being used. It is a reality based on the crystalline structure of the steel degrading with time. You just can't assume they will always be the same size just because they aren't being used:

At the level we use this sort of gauge, any growth would have negligible affect on gauge use and/or reliability.

Incidentally, we use pre-plate gauges even though the components are not plated to keep production away from the top end of the spec.
This has worked very successfully for a couple for decades now, with no thread or hole/bore defects.

If a bore tolerance is below 50µm we use an air gauge, as an actual measurement is always better at keeping things "mid limit" than an attribute pin/plug gauge.

 

[Scanton]

I'm just assuming by what you have typed... you're gonna have to use calibration labels for a while. So I would buy some folks some pizza and drinks at lunch, tell them you really need their help, and dig in and try to find out why this is occurring.

This is a great idea, I used to invite the key people to a pre-arranged (paid for) working lunch. Lay out the food and drink in a meeting from and work through your issues with them with a flip chart or whatever. Let them know what the problems are and let them come up with solutions while filing their faces with free food and drink (soft drinks). The output is usually the most obvious solution, and they may even come up with something out of left field that is very clever, but whatever it is will be their idea, so you will already have the buy in and support.

 

[Randy]

I've found requiring calibration labels/stickers to become a self inflicted wound

 

[gmeaders]

Good day @SGCalLab ;
Simple reminder.

There is no need to have a "calibration sticker". It is reasonable/acceptable to simply have an id/discrete identifier (e.g. serial number). on each device that is linked to/traceable to your calibration status tracking. It is simply not feasible to place/retain "stickers" on all types of devices in all types of situations.

Hope this helps.
Be well.

Hello everyone,
If the equipment is calibrated but has a label with a different expiration date than the certificate, how would you treat this if you were auditing it?

 

[gmeaders]

What are the "requirements" for weight sets for the scale?

 

[mhannon]

Hello everyone,
If the equipment is calibrated but has a label with a different expiration date than the certificate, how would you treat this if you were auditing it?

Depends on why the dates differ. Are they supposed to match, or does your process allow variation?
Our documented process for calibration is that we have until the last of the month until the item is past due.
If the item was calibrated today 1/24/2023, the item is due by 1/31/2024.

The calibration certificate from the 3rd party lab may say it is due 1/24/2024, but our documented guidelines in our QMS override that. I would scan that cert into our calibration database, however I would make the due date in the software the 31st. Calibration due dates by manufacturers are suggestions, and the user determines the actual frequency/interval. This has never been an issue in our AS9100 audits. You just have to be able to back up your reasoning.

If the calibration was done internally and somebody generated a calibration certificate and those dates don't match the sticker, that may be an issue.

 

[mhannon]

What are the "requirements" for weight sets for the scale?

This question may depend on what standards or certifications you subscribe to.
Obviously, you cannot put a calibration sticker on a calibrated weight or it will most certainly push the weight out of tolerance. We put a calibration sticker on the outside of the case that holds the weights. Our weights came with serial numbers laser marked on them. Those serial numbers are listed on the calibration certificate.

If your weights are unmarked you could use a removable hang tag, or if they are small <1g., you could put them in tubes or vials with labels on the outside.

Side note: I did try an experiment a while back. I wanted to use our laser engraver to mark our weights with our asset# that is in the calibration database. I figured since you can see smoke coming off of parts being marked, you are vaporizing some amount of material off of the part. Question was how much and would it be within the tolerance of a class 2 calibration weight.
I marked some scrap stainless steel and found that even a small light four digit number made the pieces 0.5 - 1mg. lighter. Definitely too much for a class 2 weight.

 

[Jen Kirley]

Hello everyone,
If the equipment is calibrated but has a label with a different expiration date than the certificate, how would you treat this if you were auditing it?

If both labels and certificates are issued as part of a calibration process, I consider certificates to be retained documents (records) and labels to be maintained documents (informative but not actual records). There are many reasons for this, but primarily the certificates contain evidence of the gages being within tolerance at time of calibration - this is a critical piece of information.