Self-locking threaded fastening element - with local flame-sprayed brass layer on threads

摘要

A screw or bolt can be made self-locking by flame spraying over a small rectangular area of the threads a metal layer of porous consistency. The metallic matl. of the sprayed layer has pref. a lower modulus of elasticity than the parent metal of the fastening element. This is a simple method of ensuring a self-locking feature. A high torque is required to unscrew an element even after many times repeated disconnection. The porous layer partly absorbs any lubricant.