Standard 12-Point Cap Screws (Steel Alloy), SDH Series

Strainsert fasteners utilize an exclusive internal gaging method (U.S. Patent #2,873,341) to indicate bolt tension due to preload and subsequent service loads with strain gage accuracy. Fasteners provide a means for accurate, independent inspection of an assembled bolt for preload, thereby enhancing the structural integrity and reliability of both the bolt and the assembly.

These 12-point Force Sensing Bolts are available from ¼" diameter up to 1 ½" diameter in many different length configurations. They are 170 KSI high strength alloy steel and can be used in counter bore applications, in place of 12-point, or many socket head bolts, or used where a small bolt flange diameter is desired.

The gaging process consists of the installation of foil type bonded strain gages in a small hole drilled along the longitudinal neutral axis of the bolt. This method compares favorably in accuracy and stability with the best external gage installations, but is vastly superior to external gage installations in mechanical and environmental ruggedness and miniaturization since the internal strain gage installation is self-protecting.

In most bolts, neither the gage or the drilled hole reduce the allowable bolt load in a Strainsert fastener. The hole depth is confined to the shank of the bolt, and the hole diameter is controlled so that the bolt cross-section through the threads is smaller than the section through the shank with the gage hole. Therefore, the gage installation will withstand and accurately indicate high strength loads.

Strainsert - for superior internally gaged force transducers.
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• Product Quality
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• Custom and Standard Designs
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