jam nut

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Last updated

June 29, 2026

Quick Summary

A jam nut is a type of locknut used to prevent a standard nut from loosening or unscrewing. It is a thin nut that is tightened against a standard nut, providing a locking mechanism. This method of locking is one of several ways to secure fasteners, alongside options like castellated nuts with cotter pins or nuts with fiber inserts.12

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…a thin nut called a jam nut against a standard nut. Another locknut contains a fibre or plastic insert near the top of the nut; locking occurs when this insert interferes with the bolt threads as the nut is tightened. The wing nut is used in applications in which frequent…
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…a thin nut called a jam nut against a standard nut. Another locknut contains a fibre or plastic insert near the top of the nut; locking occurs when this insert interferes with the bolt threads as the nut is tightened. The wing nut is used in applications in which frequent…
Read More