What is the principle behind the locking mechanism of a jam nut?

Machine Design MCQs for PPSC, FPSC, NTS, and Pakistan government job tests. Select an option below, then read the explanation.

PPSCFPSCNTSPakistan govt jobs
Subject
Machine Designmechanical-engineering-mcqs › machine-design
Published
26 Jan 2019
Last updated
28 May 2026

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Explanation

A jam nut works by placing a smaller nut on top of the main nut, then tightening the main nut against the smaller one by slightly loosening it. This action creates friction between the two nuts, preventing them from loosening. The other options describe different locking methods such as slotted nuts, nylon inserts, and cotter pins.

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