Confused about Calibration Tolerances of Plug Gauge, Ring Gauge & Snap Gauge

Dear all person in the Cove,

We use more Plug Gauge, Ring Gauge & Snap Gauge in my production process.
We have calibrated all the gauge, but we confused in applying the tolerances.
We used JIS but we still confused on use it.
When we used IT6, IT7 an so on ...
Does anyone can explain about this .....

thanks
Jhonie

jhoniegudel said:

Dear all person in the Cove,

We use more Plug Gauge, Ring Gauge & Snap Gauge in my production process.
We have calibrated all the gauge, but we confused in applying the tolerances.
We used JIS but we still confused on use it.
When we used IT6, IT7 an so on ...
Does anyone can explain about this .....

thanks
Jhonie

Click to expand...

one quick question...
why can't the IS standards be used.......

quality.shesha said:

one quick question...
why can't the IS standards be used.......

Click to expand...

Thanks Shesha ... but can you tell me the IS number ...

Jhonie

What are the Gage makers tolerance for the plug and ring gages, once you have these tolerances you can wright a procedure and create you own wear limits. for the tolerances you are working too. For example you have a plug gage with a Gage makers tolerance of +.00002 on a plug gage size of .250000, your tolerance on the parts you are checking is +/-.0010, you could specify that the wear limit is -.00004, when you plug reaches .249980 you discrd the plug member and purchase a new member. hope this helps.

jhoniegudel said:

We have calibrated all the gauge, but we confused in applying the tolerances. We used JIS but we still confused on use it.

Click to expand...

When you purchase new thread gages, order the Long Form Certificate with the gage. This certificate will give you the nominal sizes with the tolerances applied for the various features of the specific gage ordered, as interpreted by the gage maker. By comparing the Long Form Certification with the requirements of the JIS standard, you should be in a better position to interpret the JIS standard.