Jiaozuo brake

Fault Detection and Solution of Disc Brake

During the use of the disc brake, there are problems such as insufficient braking force, noise during braking, etc., which affect the normal use. We need to find the causes of the problems and solutions in a timely manner, and quickly eliminate the impact of the problems on the machine.

Reason:

(a) Brake oil leakage;

(b) There is air in the brake oil circuit;

(c) The oil seal of the wheel hub is damaged, and there is oil stains on the clamp plate;

(d) Severe brake wear and burning of the friction surface;

(e) The air pressure adjustment of the air circuit is too low.

Solution:

1. By changing the brake pad material, a slightly softer brake pad material can be used to improve the friction coefficient and increase the braking force.

2. Remove foreign objects from the debris discharge groove of the brake pad. If the debris discharge groove of the brake pad is covered by foreign objects, it will lose its function of removing dust and moisture during braking, resulting in a decrease in braking force.

The disadvantage of the disc brake is that the friction plate acts directly on the disc, without automatic friction amplification, and the braking efficiency is low. Therefore, if the brake actuating pipeline pressure required for the hydraulic braking system is high, additional power auxiliary devices must be installed; When also used for parking brake, the added parking brake transmission device is more complex than the drum brake, so its application on the rear wheels is limited.

Friction plate wear

Many disc brakes are equipped with a wear indicator. When the friction plate is worn to a predetermined thickness, the indicator will contact the brake plate and generate a high-frequency squeal. Therefore, if the above fault is found in the inspection, the friction plate must be replaced in time. (Note: Some countries may have regulations regarding the replacement of friction discs before they reach a small thickness, so the wear indicator should be calibrated according to their own requirements.)

If the wear indicator has been deformed, it is easy to replace it because it is difficult to correct its position from behind. If it is found during the inspection that the friction plate has peeled off, separated, cracked or severely damaged, or brake fluid has flowed out, the friction plate should be replaced.

SB brake usage diagram

Brake caliper 1 is generally designed to move axially relative to brake disc 4. There is a hydraulic oil cylinder 9 on the inner side of the brake disc, and a fixed brake block 5 on the outer side is attached to the caliper body. When braking, the brake fluid is pressed into the oil cylinder, and under hydraulic pressure, the piston moves to the left, pushing the movable brake pad to move to the left and press against the brake disc. Therefore, the brake disc gives the piston a reaction force to the right, causing the piston and brake caliper body to move to the right along the guide pin 2, until the fixed brake pad 5 on the left side of the brake disc is also pressed onto the brake disc. At this time, the brake pads on both sides are pressed on the brake disc, and the brake pad brake disc generates Friction torque to prevent the wheel from rotating, so as to achieve braking.

The brake disc 1 is fixed to the wheel hub, and the brake caliper 5 is fixed to the axle, which cannot rotate or move axially along the brake disc. The brake caliper is equipped with two brake wheel cylinder pistons 2, which press against the brake pads 3 on both sides of the brake disc. When the driver steps down the brake pedal to brake the car, the brake fluid coming from the master cylinder is pressed into the brake wheel cylinder, the hydraulic pressure of the brake wheel cylinder rises, the pistons of the two wheel cylinders move to the brake disc under the hydraulic pressure, press the brake block against the brake disc, and the brake block brake disc generates Friction torque to prevent the wheel from rotating, so as to achieve braking.

Damaged brake parts

When adjusting the brake caliper and friction plate of the disc brake, the installed parts (such as springs, gaskets, keyways, clamps, pins, bushings, etc.) may have been worn, loosened and aged. If they continue to be used, they may produce eccentric noise. In addition, eccentricity can also cause hot spots and glaze quality on the rotor surface, so when repairing the brake, the parts should be inspected and replaced if there are any problems.