The fatigue damage evaluation of gear in sugarcane presser using higher order ultrasonic nonlinear coefficients

Abstract

The fatigue damage of gear in sugarcane presser is one of the most common damages, which is very difficult to detect in sugar factory. The nonlinear ultrasonic technique is used to evaluate the fatigue damage of gear in this paper. The perturbation method is applied to solve the nonlinear wave equation, the relationship between relative nonlinear coefficient and higher harmonics is analyzed which the second and third order relative nonlinear coefficients are applied to evaluate the fatigue damage. The gear in sugarcane presser after three years service is the research objective, which thirty-two points at tooth root and sixteen points at tooth centre are conducted the nonlinear ultrasonic experiment. Experimental results indicate different detection points have different damage degree, and the fatigue damage degree of tooth No. 14 and 15 are more serious than other teeth. While for the same tooth, the damage degree of tooth root is much severer than the tooth centre. Therefore, the measured relative nonlinear coefficients could be applied to evaluate the fatigue damage of gear, which provides the practical method for internal damage evaluation of gear in sugar factory. Keywords: Fatigue damage evaluation, Higher order ultrasonic nonlinear coefficient, Gear detection, Nonlinear ultrasonic