Failure Analysis And Technical Improvement Of The Internal Gear In Drive Axle For A Certain Type Of Wheel Loader

The internal gear of driving axle is one of the important parts in the walkingmechanism of wheel Loader, mainly used to transfer motion and dynamic. A certain typewheel loader in service process, the internal gear of driving axle often appear failure, it notonly affects the normal use of the machine, and brought a certain economic loss to the userand enterprise. Failure analysis is an important part of the reliability engineering, and it isone of the effective ways of improving product quality. Through failure analysis of thefailure parts, find out the reasons of the failure, pointed proposed suggestions forimprovement and preventive measures, improve product quality and prolong the servicelife, and enhance the safety and reliability of the loader service. Therefore, the reasonablefailure analysis of the failure gears has an important sense.This article through to collect, statistics and induction of the failure products, andconcluded that the failure mode of internal gear are fatigue fracture of the tooth root andpinion gear knife along the back of the fracture in the groove. Through the experimentalmeans, with the aid of hardness tester, spectrum analyzer, metallographic microscope, semand other testing equipment, test and analyze the macroscopic and also systematicallyanalyzes and summarizes the quality of raw material, and heating quality, machiningquality of internal gear, and then find out the early fracture failure reasons of the gear.According to the cause of the failure, puts forward a series of technical measures toimprove this, and effectively control the quality of the internal gear that in the productionprocess, and prevent the occurrence of early failure destruction.This paper use VDI2737-2005standard check the safety coefficient of annular gearand get that the bending fatigue strength safety factor of the annular gear is too low, thenuse finite element analysis software Ansys verify the correctness of the theoreticalcalculation. Basis on this, analyze the entire structure of the internal gear with ansys andconclude that the bending fatigue strength safety factor of the annular gear is too low，cannot meet the safety coefficient of standard gear design, this was one of the main reasons ofthe internal gear fracture from tooth root. Take improve the bending fatigue strength safetyfactor as the main target, and promise not to influence the drive axle of the structuredesign and planetary gear system structure, used VDI2737-2005standard calculate thechanges of the tooth root bending fatigue strength safety coefficient with different toothroot fillet radius and different thickness rim. put forward the suggestions of improve thestructure of internal gear, and use the finite element analysis software for furthersimulation analysis, verify the rationality of the structure.