Analysis of cracking reason of brake drum

Automobile brake drum is an important functional part of the automobile, is also the main part to measure the safety performance of the automobile, but also the first part to be inspected in the daily maintenance, the relevant data show that the brake drum failure mainly has five forms: cracking, cracking, falling, excessive wear, abnormal wear. A major cause of the first two forms of fracture is discussed below -- thermal fatigue fracture caused by high temperature chilling.

Sampling plan and inspection basis

Source of the brake drum in the sample of the product is the replacement for the garage scrap products, from shijiazhuang, the city of chaff, and positive definite three areas of six repair shop purchase 30 samples, the choice of the garage are relatively large, the vehicles involved sort is more, the product model is more, and the repair shop service object is all over the country, so the purchase of samples have certain representativeness.

The location and degree of damage of the sample are different, which enables the analyst to have a more comprehensive grasp of the quality of the sample.

Samples from the sample appearance analysis, most of the damage location of friction surface crack, and brake drum causes of crack is, vehicles running down the hill too long can produce high temperature brake drum, if wade, immediately after the downhill brake drum with water and a sharp contraction, so the friction brake drum surface cracks along axis direction, this kind of crack extension with continue to brake, brake drum rupture. Some brake drums in the warranty found that the friction surface shows a piece of shiny spot, which is the brake drums in high temperature and water caused by.