Design and simulation of an adjustable amplitude vibration system for mechanical linear friction welding equipment

Abstract

This paper reports the design of an adjustable amplitude vibration system for mechanical linear friction welding (LFW) equipment. The system consists of two crank slider mechanisms that are connected by a phase modulator. The amplitude of the vibration system is determined by the average displacement of the two sliders, which can be changed by adjusting the phase difference between the two cranks. When the vibration amplitude is zero, the vibration system stays at a fixed position called positioning point. This study analyses the cause of the small amplitude vibrations of the system about the positioning point and improve the length of the connecting rod to minimize these small vibrations and ensure positioning accuracy. A kinematic and kinetic model under linear friction welding working conditions is developed based on Simulink. The simulation results indicate that after improvement of the mechanism, the system can satisfy the large loads of mechanical LFW equipment (40 kN frictional force) as well as the rapid amplitude adjustment capability and positioning accuracy requirements.