Hysteresis in threaded connections

Scattering of energy in the threaded connections influences general level of damping the dynamic processes. Therefore, the investigations of the energy scattering have been performed. Scattering of energy due to work of friction forces and formation of hysteresis loop during thread turn slip is studied. It has been shown that total seizure of all threaded connection does not occur at unloading step. Hysteresis loop have no section where variation of force is not accompanied by bolt displacement with respect to nut. Computational dependences obtained on basis of assuming the presence of such sections lead to significant overestimating of structural damping evaluation.