The Improvement Of Drum-Brake Quality Based On Finite Element Analysis

According to statistical analysis of the vehicle’s claim records, the amount of brake drum’s claim stand first on the list among the dump truck’s claim. claim for compensation is huge. Especially in Sichuan, Yunnan, Guizhou, the number of that is bigger other regions. Even some users request returning vehicle cars because of frequent brake drum’s burst, therefore we have to provide services many times in the above areas. Through investigating the spot and visiting, We find that all above regions are located in the mountain areas, the mountain roads and the long slope become the most diffcult problem of freight, though mostly among the highway. Yunnan has 19 kilometers long-slope continuous highway, In order to maintain proper speed, vehicles need a continuous braking while auxiliary brake on braking performance is poorer, so service brake system plays an important roles, the brake drum’s temperature rises highly, the temperature of brake drum reaches more than 300 degrees Celsius, vehicle braking system declines seriously. Actual failure mode of the brake drum, such as bursting, off the bottom, cracking and et., High disaster frequency is an important factor which causes the amount of brake drum’s claim stay in a high position without going down. It is the important point for reducing brake drum’s claim, that’s the primary task in the work of commerical vehicle’s product development and quality improvementThis article study on the dump truck’s brake drum, We focus on studying actual failure mode and design optimization for the brake drum, the finite element analysis model is established for drum-brake by ABAQUS software. 20 times braking under normal road conditions and hot crack conditions are mostly analyzed. Under these two conditions, the boundary conditions are defined, the temperature and strength of the brake drum are calculated, we analyze the reasons for the failure of brake drum, the number of failures and position on the brake drum are forecasted.In order to verify the correctness of the finite element method(fem), We design the bench test, develop the test preparation with the test equipment and complete three sample’s bench test. First we have obtained the brake drum’s temperature after measuring 20 times braking under normal road conditions. Through the comparison of three samples, We have found that the bench test is consistency, the temperature trend is consistent, comparing with the finite element calculation results, the temperature variation regularity or the last temperature result, That of the bench test’s coincide with the finite element results. The same three samples have been tested after carrying on the brake drum’s hot crack condition test, measuring the brake drum’s temperature and cracks on the surface of the brake drum. We find that the micro cracks appear in all the brake drum after 30 times brake, After extending the micro cracks cause the failure of the brake drum, comparing with the finite element calculation results, the number of cracks in the brake drum is highly consistent. The test results of normal road conditions and hot crack conditions validate the correctness of the finite element model.From the finite element calculation results and the brake’s test results can be seen the weak spot location of brake drum, after the 30 th thermal fatigue test of brake drum, the thermal fatigue cracks will appear; In order to improve the service life of brake drum, the improved scheme of the brake drum is proposed: We have optimized the structure of weakness region and improved designment on the pitch of slope for the brake drum through the finite element model calculation prediction, The brake drum’s service life have been improved significantly.