Characteristics of Threaded Joints in Ultrasonic Vibrating System

Abstract

In order to develop the most suitable design method of the threaded joints in an ultrasonic vibration system, the effects of dimensions of threaded joint, form accuracy of bearing surface and tightening force on the characteristics of transmitting ultrasonic vibration are investigated experimentally and theoretically. The obtained results are as follows: 1) The methods, which evaluate the characteristics of the threaded joints in the ultrasonic vibration system by detecting the critical stress amplitude at bearing surface and the motional admittance, are proposed. 2) In the case o high accuracy of bearing surface the critical stress amplitude is approximately equal to the mean stress on contact surface and the mechanical resistance is close to that of solid bar. In the case of low accuracy of bearing surface the critical stress amplitude is much lower than the mean stress on contact surface and the mechanical resistance is larger than that of solid bar.