Something you should Know about Brake Pads
March 28,2022
The brake pad is the automobile brake lining, which is the friction material fixed on the brake drum or brake disc rotating with the wheel. The friction lining and friction pad bear external pressure to produce friction effect, to achieve the effect of vehicle deceleration or stop.
Therefore, the brake pad is a vital part of the automobile, which is related to personal safety.
Today, let's talk about brake pads in detail.
Main properties of brake pads
The performance of the same brake pad is very different under different temperatures, different speeds, and different braking pressures.
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Braking performance
It refers to the breaking capacity (friction coefficient) of the brake pad under normal braking conditions (relatively low braking temperature).
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Decay performance
Under the road conditions such as downhill and mountain roads, the temperature of the brake rises rapidly after continuous braking, and the temperature of the brake disc may reach more than 400, 500, or even 700 degrees Celsius. The braking capacity of the brake pad will deteriorate and the braking distance will increase. This phenomenon is called "recession".
The decline rate of high-quality brake pads is very small, some even do not decline, while the decline of some fake and shoddy products is very serious, and they almost lose their braking capacity at high temperatures.
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Recovery performance
After high-temperature decay, can the original braking performance be restored as soon as the temperature drops? This is also the importance of measuring the quality of brake pads.
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Brake pad wear
This is the wear of the brake pads when they are in use. The braking effect depends on the formula and process of the friction material. In addition to the wear of the brake itself, the wear of the brake pad should also be considered. In the braking process, the high-quality brake pad will generate a protective film on the friction surface of the brake disc to reduce the wear of the brake disc, while the low-quality brake pad contains a large number of hard spots and impurities, which will pull out many grooves on the surface of the brake disc to accelerate the wear of the brake pad and brake disc.
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Noise
In today's environment-friendly society, this is also a very important indicator. There are many factors causing braking noise, and the brake pad is only one of them. It is generally believed that if the hardness of the brake pad is too high, it is easy to produce noise.
The service life of brake pads
This is not a definite statement. Different cars, different driving habits, and road conditions have different wear on the brake pads.
Generally, the frequency of replacing the brake pads is about 30000 kilometers. If the brakes are not too hard, the brake pads can run 10000 kilometers more. They need to be checked at 30000 kilometers.
If there are no brake pads, it will be very dangerous. Now, most cars have brake pad alarm lights. If the brake pads are worn thin, the instrument lights will alarm.
If the car hasn't worn out after 70000 to 80000 kilometers, the brake pads are too hard and bad for the brake discs. It is recommended to replace the brake pads.
The best time for brake pad replacement
- The thickness of the brake pad is less than the minimum maintenance standard allowed by the vehicle manufacturer;
- The wear alarm switch on the brake pad has given an alarm;
- The brake pad is polluted by oil or grease;
- When the brake pad makes abnormal oil noise when braking, generally, if the thickness difference between the two sides of the brake pad on the fixed brake caliper reaches 1.5mm and the thickness difference between the two sides of the brake pad on the floating brake caliper is 3.0mm, it needs to be replaced. However, it is impossible to accurately determine whether the brake pad is worn only through simple appearance observation. It is best to use a ruler to measure whether the thinnest part of the brake pad is within the allowable range.