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How does bolt length affect testing?

A correctly installed bolt in an assembly will be flush or have up to three threads exposed from the nut.

Many sources including the Specification for Structural Joints Using High-Strength Bolts (pdf) state that flush to three threads is the proper amount of bolt stick through for a faster assembly.  This specification should be followed when testing bolts since the goal is to replicate the job site faster assembly as closely as possible.

All adapters and testing units are sold by diameter so knowing what equipment is needed to test a particular bolt diameter is fairly straightforward.  Bolt lengths, on the other hand, require an understanding of bolt testing equipment because there are several different solutions based on the length of a bolt.


Testing equipment related to bolt length

    • Spacer Kits

    • Short Bolt Adapters

    • Torque Reaction Kits


      1. Spacers are added to a bolt testing solution to achieve proper thread stick through.  Watch our video on spacer usage for more information.







      2. Short bolt adapters are sometimes needed to test shorter lengths on a Model MZ or the Model HS.  Please review our Minimum Bolt Length chart to see if short bolt adapters are needed.





      3. A torque reaction kit is required for all tightening tools with reaction arms.  If your tool utilizes a torque reaction arm please use our Quote Request Form to give us the information needed to provide the correct testing solution.



      Bolt length is important because it determines whether or not the bolt is considered acceptably engaged within a faster assembly.  If you have any questions related to bolt length or bolt testing in general please don't hesitate to contact us and we will get you the information you need right away.


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