Failure reason analysis of automobile brake drum

1. Failure reason of cracking

Automobile brake drum will be affected by various forces in the normal operation process, mainly including the normal pressure of horseshoe, rotation and the shear force of the splice of the shoe. The two forces complement each other, and if the normal pressure does not exist, the tangential force will disappear. However, in the normal operation process, there will be friction and heat generation between the two, at which time the brake drum temperature will continue to rise, and the friction between the two is a speckle contact friction, so the contact surface will also undergo a phase transition phenomenon when subjected to friction heat generation, and finally produce phase transition stress. The phase transition stress will lead to uneven force on the brake drum, which will lead to regular cracks under the frequent braking load of automobile brake drum.

2. Analysis of cracking failure causes

Brake drum cracking also covers two layer causes. Firstly, the brake drum will be affected by the difference in material strength, leading to cracking. Secondly, after the brake drum cracking problem occurs, the brake drum will have local phase change under the interaction of thermal stress and phase transition stress, leading to a decrease in strength. At this time, the brake surface crack will continue to expand, leading to cracking phenomenon.

3. Cause analysis of bottom failure

In the automobile brake drum does not appear under the premise of cracking and direct cracking, this is the bottom failure, it will lead to the brake drum direct failure. Specifically, it also includes two points: firstly, the brake drum material strength is not good, secondly, under the action of some unreasonable abnormal external forces, the brake drum will also be affected by torsion force and indirectly occur cracking phenomenon, at this time the brake drum flange layer will appear crack cracking phenomenon, finally causing the bottom problem.

4. Excessive wear and the wear failure of the original analysis wear costs too much and wear can easily lead to automobile brake drum thoroughly failure, said first wear is too large, it refers to automobile brake drum work in the channel with braking effect under the action of the brake drum working this rare variant geometric size bigger and bigger, wall thickness is more and more thin, directly to the brake drum brake effect is a negative impact. Look at the abnormal wear failure, when the brake drum working face in the shoe and other hard things under the action of external forces, its due to friction contact groove will appear, to a certain extent is due to the automotive brake drum hardness caused by insufficient!

In a word, automobile brake drum crack failure reasons are various, it is generally produced by the brake belt working face as the beginning, with the increasing brake working strength, the brake surface will crack, leading to the failure of automobile brake drum.