D1342 Brake Pads

The friction problem of the auto disc brake pads.

There are many indicators for automotive disc brake pads, and we often hear shear and friction coefficients. The friction coefficient of the friction material is related to the magnitude of its braking force. The coefficient of friction is not a constant, but a value that changes due to factors such as temperature, pressure, friction speed, or surface condition and surrounding medium.

The ideal coefficient of friction should have an ideal coefficient of cold friction and a controllable temperature decay. Since friction generates heat, the operating temperature is increased, resulting in a change in the friction coefficient of the friction material. Temperature is an important factor affecting the friction coefficient. During the friction process, due to the rapid increase of temperature, the general temperature reaches 200 °C and the friction coefficient begins to decrease. When the temperature reaches the resin and rubber decomposition temperature range, the friction coefficient will suddenly decrease. This phenomenon is called "thermal decay". A severe "thermal decay" can result in poor braking performance and deterioration.

Auto disc brake pad structure

The automobile disc brake pad is mainly composed of a back plate, a bonding heat insulation layer, a friction material layer, a sound absorbing sheet and an attachment. The friction material layer is composed of a friction material and an adhesive. When braking, the friction material rubs against the brake disc to generate a braking force, thereby decelerating the vehicle. The bonded thermal insulation layer is composed of a material having a low heat transfer rate for the purpose of heat insulation. Due to the friction between the brake pad and the brake disc, the friction material layer will be gradually worn out, so the friction material layer of the brake pad should be replaced in time after using the limit, otherwise the back plate will directly contact the brake disc, which will not only reduce the braking effect, It even caused damage to the brake disc or malfunction of the brakes.

Auto disc brake pad replacement

When replacing the auto disc brake pads, the brake cylinder must be used to push the brake cylinder back. It cannot be hard pressed with other crowbars. Otherwise, the guide screws of the brake caliper will be bent and the brake pads will be stuck. After replacing the brake pads, be sure to step on the brakes to eliminate the gap between the brake pads and the brake discs to avoid accidents. At the same time, when we check the remaining thickness of the brake pads, we also check the wear state of the brake pads. The degree of wear on both sides is the same. Whether the return position is free or not, it is necessary to deal with the abnormal conditions immediately, and the brake pads must not wait for the friction material. They are all replaced before they are worn.