Abstract: In order to study fatigue life of rear axle housing of the first Chinese SF33900 mining dump truck, the finite element model of rear axle housing is built. Stress analysis and experimental results are compared, which finds out that the margin of error is acceptable and verifies the accuracy of the model as well. Regarding dynamics analysis results as random load of fatigue life analysis of rear axle housing, fatigue life contours are obtained under normal conditions and the minimum life meets the engineering requirement. For the purpose of studying the sensitivity between load change and fatigue life, the impact of fatigue life under amplitude changes of the three loads is contrastively analyzed, which gets that the load of rear tie rod and suspension have greater impact on fatigue life of rear axle housing. Otherwise, the change of load frequency also plays a great role in fatigue life. The results show that the change of load frequency has a greater influence on fatigue life of rear axle housing than the change of load amplitude.

Key words: Fatigue life, Load frequency, Ming dump truck, Random load spectrum, Rear axle housing, Sensitivity