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How to Purchase a Thread Plug Gauge

Thread plug gauges are essential for checking screw threads and calibrating gauges. By using them, your company will have greater uniformity and will be able to meet quality control standards. The class of fit for the gauge measures the tolerance that is allowed for the class. Class 1a has the widest range of tolerances and is great for when the parts need to be assembled quickly, while the other classes are ideal for when a more specific calibration is needed. There are many thread plug gauges that are available on the market, and there are many companies from which these thread plug gauges can be purchased from.

Reversible Thread

Reversible thread plug gauges are helpful because they allow for one of the ends to be rotated. This allows for there to be two gauges in one. The thread gauge head that has been worn out can be used again by reversing the gauge. This is beneficial for high volume applications. These thread plug gauges come with a chrome coating that extends the life of the thread plug gauge.


Taperlock thread gauges use high quality, oil hardened tool steel. They use chip grooves on all larger sizes. These gauges are sometimes chosen because they are less expensive than reversible thread plug gauges.


A trilock style gauge is like the reversible thread plug gauge in that there is more than one side on the gauge that can be used. Like with reversible thread plugs, it provides two gauges in one. These gauges check internal threads to make sure that they are designed inside a tolerance limit.


Taperpipes are used to check the functional size or the tight engagement of the couplings. These gauges check the crest truncation and profile of internal threads that are used in conjunction with a L1 plug.

There are many other options to choose from, including the:

  • Variable
  • Straight pipe
  • Truncated setting
  • Helical coil

Determine which type would best fit your applications, and then look for the right company to purchase one.

Finding The Right Company

The best companies to purchase thread plug gauges from are those that provide customer support to those who are having technical issues with their thread plug gauges. Choose thread plug gauges that are precision hand-lapped and polished. This will ensure that the product has better accuracy. The gauges should come with an NIST certificate of accuracy for all gauges. Ideally, it should have go or no-go members.

For more information, contact a company like WESTport.

8 March 2017

WESTport Manufactured Products. 24th Anniversary Servicing Industry Worldwide (1989-2013)