Drum Brake Has Stronger Braking Force. Why Do You Still Pursue Disc Brake(2)?
In fact, there is a common prejudice against drum brakes. For example, many people think that disc brakes are used in racing cars and luxury cars, and the heat dissipation of drum brakes is worse than that of disc brakes. Therefore, disc brakes are definitely better than drum brakes.
First of all, the heat and water resistance of the drum brake is worse than that of the disc brake. That is to say, when the temperature of the brake system rises or rain enters the brake drum, the braking performance of the drum brake will decline. As the brake disc is always exposed to the outside, the heat generated in the braking process will be quickly dissipated by the brake disc, so the braking performance of the disc brake is better than that of the brake disc.
But I thinks that in the actual braking process, people ignore another key factor that affects the braking force, that is, braking
Generally speaking, the higher the equilibrium reflux boiling point of the brake oil (that is, the boiling point of the brake oil), the better the braking effect of the car. However, because the brake oil will be mixed with a certain amount of water after a period of use, the wet equilibrium reflux boiling point of the brake oil will also determine the braking performance of the vehicle in the process of driving.
And the thermal attenuation of the brake force of the drum brake is not as fast as we think. Generally, when the temperature of the brake drum reaches 400 ℃, the thermal attenuation of the brake system is still relatively small. Only when we brake for a long time and frequently in the process of driving, the braking effect of drum brake in this high temperature environment will weaken.
For example, when we drive a racing car, the frequency of brake and accelerator is much higher than when we drive a passenger car normally. In this case, if we use the drum brake system, all the weaknesses of the drum brake will be exposed. In our daily driving process, the braking effect of drum brake is not worse than that of disc brake, even stronger.
To sum up, this paper introduces in detail the limit value that the passenger car disc brake can bear, the inherent advantages of the drum brake in structure, and some performance characteristics of the drum brake and the disc brake. Therefore, in the field of passenger cars, the old drivers think that the braking effect of the disc brake will be better than the drum brake. This conclusion is one-sided.