Serial Numbers on Gage Blocks?

[gibu2]

Hello, First time posting here.

I have searched the forum and haven't quite found an answer to my question so I thought I would go ahead and post. Sorry if this has allready been answered somewhere.

We are just now implimenting AS9100 and are getting ready to calibrate all the measuring tools in the shop including employee tools. We use a lot of mics and calipers and such. We purchased a calibration set from Long Island Indicator to use just for calibrations exclusivly so we wouldn't be using any Jo Blocks that are used on the floor. This set pretty much only goes up to 1 inch though but every block in the set has it's own serial number. We want to add new blocks to this set to increase the tool sizes we can calibrate with it. A two inch block three inch block, whatever. We are having a rough time finding individual blocks with serial numbers on them however. At least without paying an arm and a leg for them. Our boss would like to just purchase a whole new 81 block set or something for just slightly more then the cost of the individual serial numbered blocks.

My question is, does each block used in calibration have to have it's own serial number? If it doesn't can we number it our selves and add it to the calibration kit we allready have to cut down on the recording of so many numbers?

Thanks

 

[Jerry Eldred]

The key word, I believe, would be traceability (unique block to unique calibration). You should be able to know what specific block calibrated what specific caliper or micrometer.

Whether you buy pre-serialized blocks, or serialize them yourselves should not be an issue.

In the case of replacement blocks, you need to identify the replacements uniquely compared to originals of the same size. In the case of added blocks, you need to create unique identifiers for them. I don't know of a requirement that you must use a manufacturer's serial number; only for unique identification. The manufacturer's serial number allows them unique identification of their shipped product, and is a convenience for the user. In other instruments, I have often had to create a serial number to provide that "unique identification."

The bottom line is that any calibration to a micrometer or caliper needs to trace to an identifiable source. As long as you have a unique idnetification of a specific block (including its correction factors) that is used for a calibration (including unique identification of the calibration to the block), I believe you should be fine.

The above is a simplification - there are other peripheral details not covered for the sake of simplicity and clarity.

 

[gaugefixer]

QUOTE: My question is, does each block used in calibration have to have it's own serial number? If it doesn't can we number it our selves and add it to the calibration kit we allready have to cut down on the recording of so many numbers?

Each block does not need to have it's own serial numbers. If you do add to the set make sure you get the same class and type of gauge block as you already have. When you get the set of blocks calibrated, they will be identified as the block size; ie: .143"; .250"
Your'e probably better off to get a decent 81 pc. set of blocks and use them as your calibration masters set.
One suggestion: Limit the number of people who has access to them and lock them up before you go home. I've found master gauge blocks on the shop floor because people couldn't find the block they needed from 5 sets of shop floor blocks.

 

[Claes Gefvenberg]

I have nothing to add to the good advice already given so I'll just stick to wishing you welcome to the Cove, gibu2

/Claes

 

[Hershal]

Welcome to the Cove, gibu2.....

Individual blocks are not required to have their own s/n.....additional blocks as you mentioned acquiring will benefit from it however, so that the cal house can assure that the cert goes to that block.

Of course, I recommend using an accredited calibration provider.

The 81 pc set may be the better option in the long run though.

I agree with gaugefixer that access should be limited and the blocks controlled.

Hope this helps.

 

[gibu2]

The bottom line is that any calibration to a micrometer or caliper needs to trace to an identifiable source. As long as you have a unique idnetification of a specific block (including its correction factors) that is used for a calibration (including unique identification of the calibration to the block), I believe you should be fine.

Thanks for all the great input everyone, it's very much appreciated. Looks like the larger set may be the way to go. The one question a co-worker had when reading the responses was when Jerry mentioned the blocks correction factors. Wouldn't an 81 piece set just have a tolerence range for the blocks in the set. The calibratin set with individually numbered blocks had the correction for each block listed right on the cert. If we used blocks from a lerger set that didn't have specific correction values would we need to have those blocks cailibrated to find the correction value for the indivdule blocks we will be using? Or would we just use the tollerence range?

Thanks again every one and thanks for the welcome. I'm sure I will have lots more questions to come in the future.

 

[rich.dittmanjr]

Gage Blocks

In our lab we have to order replacement block for our worn or missing blocks from the sets. We order our replacement blocks from Starrett and request that the serial number of the lost, or out of tolerance block be eteched on the block as well as the date. This is in case it was lost block. Of course get the blocks with a certificate of calibration. We found this works great!

Rich