Calibrating Taper Sleev/Plug Gauge

fahimk

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Hello,

I am looking for calibration procedures of the following:
1) Taper Sleev Gauge
2) Taper Plug Gauge

Can anybody help me identify the sources? Would appreciate if shared relevant guides...

Thanks.
 

Jayfaas

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bump. I would like to know this as well. From what I can gather, the tapered master plug gauges are created based off of a spec, but there is no tolerancing set for the different points along the taper. I noticed that sending it back to the manufacturer, they would measure it and certify it, but my question is to what tolerance limits? My thoughts are....in order to be a successful calibration, especially for a plug gauge, you have to have some sort of tolerancing. These are being used to essentially calibrate other non-variable gauges. At the very least, I would think you set an inside line and outside line tolerance and allow for wear, or put some kind of tolerance on the worn line to make sure that whatever you are checking would still atleast be in spec. I would love to see how other people in the industry handle this.
 
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dwperron

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bump. I would like to know this as well. From what I can gather, the tapered master plug gauges are created based off of a spec, but there is no tolerancing set for the different points along the taper. I noticed that sending it back to the manufacturer, they would measure it and certify it, but my question is to what tolerance limits? My thoughts are....in order to be a successful calibration, especially for a plug gauge, you have to have some sort of tolerancing. These are being used to essentially calibrate other non-variable gauges. At the very least, I would think you set an inside line and outside line tolerance and allow for wear, or put some kind of tolerance on the worn line to make sure that whatever you are checking would still atleast be in spec. I would love to see how other people in the industry handle this.


Here are a couple of links to resources regarding tapered thread tolerances:

NPT Thread Dimensions: A Complete Guide - EngineerExcel

National Pipe Thread (NPT): Dimensions& Formulas
 

DietCokeofEvil

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Your equipment is vaguely stated, which is why I assume you are not getting answers. Are you talking about plain tapers or NPT gages?
 

Jayfaas

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I am referring to tapered spline gauges used for checking the wear on spline ring gauges. There are 3 lines along the taper for measuring wear, but no tolerances are given and even when I got with the company about this concern, there was alot of back and forth and didnt really get a good answer. My issue is that I can send one back to them and they will certify it, but to what? They stopped putting “passed” on their certs, and this is probably why. We do our spline gauge verifications internally using a CMM and gear software, but if you dont have tolerances, you dont know.

At the very least if I knew what the tolerances were at the new and replace lines, I could maybe make an argument that it measures within the window, but I cant because I dont know. The measurements on the print and original cert are the measurements they got at those locations, and thats it.
 

Jayfaas

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Jim,
Thank you for the link. Unfortunately I do not have access to that. I believe that it would help with tolerances for regular splines, but since these are tapered, I am trying to understand how they are supposed to be verified. I assume the gauge maker creates them with the 2 of the lines on the spline indicating the spec limits and the 3rd in the middle indicating the wear. However, because the dimensions at those lines from the original certificate are just the initial verification readings after being manufactured, who knows? There are no tolerances, and with that, how are you supposed to verify a gauge? They are used to check spline ring wear, but there has to be something in place that will eventually trigger the thought that maybe the tapered plug is finally worn out.
 
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