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New Thread Check Catalog

Thread Check Inc., is proud to announce the release of our 2016 Precision Gage Solutions catalog with over 180 pages of precision gages, measuring instruments and technical information. Our new catalog is available for download or in an electronic book format for easy use. The new catalog has links to where our customers can shop on line, request quotes and view hundreds of technical articles. Use the table of contents to quickly turn to the product selection of your choice. Use electronic book marks for the pages you visit frequently. The new electronic catalog works across all platforms including tables and smart phones.

Thread Check Catalog 2016 Cover




Thread Gaging Product acceptability

System 21

System 21 specifies for interchangeable assembly with reference to functional size only. System 21 specifies that functional size must be measured at the maximum material limit within the length of standard gaging elements. System 21 requires that the NO GO functional diameter must also be verified. This can be accomplished by using a fixed limit gage such as a GO/ NO GO thread plug gage or a variable gage with functional elements such as thread rolls

System 21A

Metric threads per ANSI B1.18M

System 21A specifies for interchangeable assembly with functional size verified at the maximum material limit using standard length gaging elements. This can be performed by using fixed limit gaging such as GO/NOGO thread plug gages or with variable gaging through the use of functional elements. System 21A also requires that the minimum pitch diameter (minimum material limit) be verified by inspecting two thread flank location over the length of the thread. This can be performed with a variable gage or a thread roll snap gage with pitch diameter elements.

System 22

System 22 specifies for interchangeable assembly with functional size verified at the maximum material limit using standard length gaging elements. This can be performed by utilizing fixed limit GO/NOGO gaging or variable gaging with functional diameter elements. In addition System 22 requires the verification of the minimum pitch diameter (minimum material limit) over the full length of the thread. This can be performed by using variable gaging such as pitch diameter elements.

System 23

System 23 specifies for interchangeable assembly with functional size verified at the maximum material limit using standard length gaging elements. Minimum pitch diameter (minimum material limit)  must be verified over the full length of the thread. System 23 includes all the requirements of System 22 as well as the independent verification of lead, flank angle, taper and roundness.
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Functional Size Thread Inspection

Functional size thread inspection is fast, easy to use, affordable, and versatile for inspecting threads. The Gagemaker PG-6000 and RG-7000 functional gages use two precision ground thread rolls that seat into the thread form and contact the thread at the pitch line. The gages are zeroed at a preset calculated thread size. Deviations from nominal size are read on the indicator. Thread rolls are able to determine variations in form, lead, taper, and height all simultaneously just as the thread plug and ring gages do. The PG-6000 and RG-7000 are set using gage blocks, micrometers, or Gagemaker’s MIC TRAC measurement center. Thread ring and setplug masters are not required.

The PG-6000 Series gages inspect diameters of internal threads. The RG-7000 Series gages measure diameters of external threads.

Common pitches ranging from 4 TPI to 20 TPI of the UN Series, ACME, and Stub ACME, and 1.5mm to 4 mm of the ISO Metric thread rolls are in stock. Whitworth and 7° X 45° Buttress thread rolls are available with short lead time.

With the PG-6000 and RG-7000, thread diameters up to 24 inches can be easily and accurately measured.

Functional Size Thread InspectionFunctional Size Thread InspectionThread Inspection

Thread Inspection


Gagemaker Distributor Conference 2012

Gagemaker Thread Gages

Thread Check Inc. attended the Gagemaker 2012 Distributor conference in Houston Texas this past week. Thread Check was represented by its President Bart Kipnes, VP of Sales Mark Koszyk, and General Manager Glenn Belmonte. The conference included training and workshops that covered Gagemakers core group of products including Straight Thread Inspection, Tubing and Casing Inspection,, Rotary Shouldered Connection Inspection, Mud Motor Power Inspection, and Measurement and Calibration.

Gagemaker's products are ideally suited for large diameter inspection as well as accurately inspecting all the critical elements of a thread including lead taper, thread depth, profile, functional diameter and pitch diameter. Inspection Kit packages are available that make implementing a quality thread inspection fast and easy.



Calibrating Thread Comparators

Regarding calibration of internal and external thread comparators:

For the Internal Thread Comparator, calibration requires ispecting for wear only. The segment fingers are made as a unit then cut in half. The only element that can be measured is the form of the thread, and the only issue that would make these unusable would be wear on the thread form.

In regards to the Tri-Roll Thread Comparator, the thread measuring rolls are required to spin so this should eliminate the possibility of wear. Recalibration covers evaluating for wear and damage do to misuse and neglect.

It is important to make sure rolls are not locked down during use.

Recalibration covers inspecting both segments and rolls to original manufacturing specifications

Original manufacturing specifications are proprietary and not for release or publication.


Contact Thread Check Inc with with questions or comments.