Pin Gage Use vs. Calibration Frequency

K

kgriff

I have a dilemma that I've been trying to overcome for many years and, for some reason, just now thought to post here.
We have many library pin gage sets. These are mostly 0.061-0.750 sets. Class Z and ZZ.
The pins are identified by set using paint on each end of the pin. Most of our pin sets, based on their usage and criticality are on 2 year intervals. (For key feature measurements we use X Class, Air Gages, or Bore Gages.) The pins are primarily for setup, so it is important that they be "close" to the marked size, but as they are not used for final part inspection it is not critical.
I have tried to come up with a fairly fool-proof way of identifying pins so that, when it is time for calibration, pins that have been used are obvious and require calibration. Pins that do not get used would have an extended calibration interval.
We have tried sign-out sheets which, obviously, doesn't work. We have tried dip-sealing the exposed end of the pin with the intent that the dip-seal be removed when the pin is used. This has also not worked. As often as not, the dip seal is used as a "handle" when the pin is removed from the drawer, then the pin is replaced with the dip seal intact.
Does anyone have any ideas of how to accomplish this? Or has anyone done anything like this with any degree of success?
Whatever I do, it has to be rigorous enough to "ensure" that a pin cannot be used without the usage being obvious, such that the pin will be calibrated at the next due date.
And yes, we could argue that my use of the term "calibration" should instead be "verification", but that is a semantic discussion. For the purpose of the paragraphs above, I would not technically be "calibrating" any pin, since adjustment is impossible.
 
C

Curtis317

Just a thought.... you might want to use different colors for the ends of the pins. Green for January calibration, Blue for Feburary or some logical color scheme on the ends of the pins. That way for a given month (or before that month) you gather up those pins for calabration.
 
H

Hanr3

We also have calibration intervals based on useage. We control the usage via gage lab personnal. They check out the gage and record the number of day the gage was checked out. We use a software program to control calibration records. When our predetermined interval approaches, we send them out for calibration.

Any time you have open access, you cannot control the system. You could restrict access numberous ways. Supervisor or team lead has a key and is responsible to log out the gages. You will also need a system to ensure the gages get returned after usage. Otherwise they will remain on teh floor, subject to damage. After usage- could be after the job is complete, or after the physical usage, up to you to define based on how your business operates.
 

Michael_M

Trusted Information Resource
We use a 'calibrate prior to use' system for our gauge pins. Can you forgo the calibration and use a calibrated Micrometer to 'verify' the pin diameter before each use?

If the pin is worn, remove and replace.

I don't know if this will work for the standard you are following.
 
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Mikishots

Trusted Information Resource
I have a dilemma that I've been trying to overcome for many years and, for some reason, just now thought to post here.
We have many library pin gage sets. These are mostly 0.061-0.750 sets. Class Z and ZZ.
The pins are identified by set using paint on each end of the pin. Most of our pin sets, based on their usage and criticality are on 2 year intervals. (For key feature measurements we use X Class, Air Gages, or Bore Gages.) The pins are primarily for setup, so it is important that they be "close" to the marked size, but as they are not used for final part inspection it is not critical.
I have tried to come up with a fairly fool-proof way of identifying pins so that, when it is time for calibration, pins that have been used are obvious and require calibration. Pins that do not get used would have an extended calibration interval.
We have tried sign-out sheets which, obviously, doesn't work. We have tried dip-sealing the exposed end of the pin with the intent that the dip-seal be removed when the pin is used. This has also not worked. As often as not, the dip seal is used as a "handle" when the pin is removed from the drawer, then the pin is replaced with the dip seal intact.
Does anyone have any ideas of how to accomplish this? Or has anyone done anything like this with any degree of success?
Whatever I do, it has to be rigorous enough to "ensure" that a pin cannot be used without the usage being obvious, such that the pin will be calibrated at the next due date.
And yes, we could argue that my use of the term "calibration" should instead be "verification", but that is a semantic discussion. For the purpose of the paragraphs above, I would not technically be "calibrating" any pin, since adjustment is impossible.

Don't get caught up citing semantics, as adjustability has nothing to do with it. Calibration is a comparison between measurements.

Usage is not the only reason for a tool such as a pin gauge to become OOT. It almost seems that the amount of effort being expended in determining which pins need to be checked vs. the ones that are to have their due dates extended outweighs simply performing the check on the set when due. Extended or not, you need to do all of them sooner or later.

Considered outsourcing?
 
O

oldcodger

We have the same dilemma with other gauges (like thread ring gauges). We decided we really need to control/track gauges that are issued and used to calibrate parts. We feel we are spending way too much time and money recalibrating gages that have not been used (or touched for that matter) since the last time they were calibrated. We decided that we need to control and keep specific records of what gage was issued to whom (and for what job). If we do this?keep detailed records, I feel that we will have sufficient evidence to show auditors why gauges were skipped and not recalibrated?if we show specific evidence that the gauge was not used. We are currently using a paper system to do this with varying success. We are actively searching for a software program to help us.
 

Mikishots

Trusted Information Resource
We have the same dilemma with other gauges (like thread ring gauges). We decided we really need to control/track gauges that are issued and used to calibrate parts. We feel we are spending way too much time and money recalibrating gages that have not been used (or touched for that matter) since the last time they were calibrated. We decided that we need to control and keep specific records of what gage was issued to whom (and for what job). If we do this?keep detailed records, I feel that we will have sufficient evidence to show auditors why gauges were skipped and not recalibrated?if we show specific evidence that the gauge was not used. We are currently using a paper system to do this with varying success. We are actively searching for a software program to help us.

If you feel that you're spending way too much time and money recalibrating gauges that haven't been used, it can be assumed that there are a lot of gauges that fall within this category. So now you keep detailed records - paper-based - to keep track of all these items and to provide evidence to an auditor why they were skipped and not calibrated.

Help me understand how this is better. If providing evidence to an auditor is more important to the company than having tools that are verified as fit for use, the process is not being done for the benefit of the customer. This may sound like a great idea to start with, but before you realize it, you're going to have pin gauges from the same set that have many varying calibration dates. So now, instead of identifying a set as calibrated, one has to identify each pin gauge individually.

Time and effort cost the company money as well, not just calibration fees.
 
O

oldcodger

We have thousands of thread ring gauges. We have hundreds "obscure" thread ring gauges that are used infrequently (if ever). Currently, ALL gauges (even the "obscure" ones) are checked for calibration on a regular basis. Our goal is to find an efficient way to manage these types of gauges better and save time. Our goal is to segregate seldom used gauges from the calibration process if they haven't been issued/used. Our plan is to implement a software program that will keep track of gauges that were issued to jobs since the last calibration. We will ensure these gauges are in calibration on a regular basis. If a gauge has not been issued or used, we will leave it in the cabinet in a calibrated state--all thread gauges are currently in a calibrated state. If a gauge has not been calibrated in three years, we ensure it is in calibration before issued to a job. There is nothing in this scenario to suggest we are issuing out-of-calibration gauges. We are also confident this will save time and money.
 
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W

Walleye

We calibrate our Ispection pins every 6 months, common pins are calibrated when they are returned to me. Therefore when we put common pins away they are calibrated and checked before they are used again and can also be verified by operater if needed.
 

Buckyb

Involved In Discussions
I know this post is kinda old but...... what is wrong with the calibration interval being indefinite with a written procedure or process defined to replace damaged or lost pins and gages as needed? If they are very rarely used; why spend the money, time, resources chasing what was and was not used? Where is the value add? The Standard states that "the organization shall maintain MME and define the process employed for............frequency of checks, check method and criteria". If pin gages and gage blocks are purchased with certification, it is likely they will stay in tolerance until damaged or lost. Continued use (unless misuse) is not likely to change the tolerance. I'm just sayin'
 
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