FORMULATION OF A CRITERION FOR PREVENTING SELF-LOOSENING OF THREADED FASTENERS DUE TO CYCLIC TRANSVERSE LOADING

摘要

In the paper, a novel criterion is developed for preventing the self-loosening of preloaded threaded fasteners under cyclic transverse loading. For a known cyclic excitation, the system parameters are used in the formulation of a closed form solution for the minimum fastener preload required for preventing self-loosening. The effect of several key variables is investigated; this includes bearing and thread friction coefficients, bolt grip length, thread pitch, material, and the cyclic amplitude of the transverse excitation. An experimental setup and test procedure is established. Comparison between the experimental and analytical clamp load variation results shows that the proposed criterion can accurately predict the requirements for preventing self-loosening.