Wheel Brake Cylinder - BWH399 TRW

The main work in the braking system of a car is assigned to the brake cylinders. It is on their proper operation that the effectiveness of slowing down or stopping the machine depends. The working (wheel) cylinder is the executive doing the brake system. They are installed between the brake pads and provide their expansion and compression. The design of the working TRW brand Wheel Brake Cylinder is simple: they consist of a cast iron body with two pistons, between which there is a cavity for the brake fluid. Outside, the wheel brake cylinders have fasteners for connecting to the brake pads and the brake master cylinder.

1. GOLF III (1H1)
2. GOLF Mk III (1H1)
3. GOLF III Variant (1H5)
4. GOLF Mk III Estate (1H5)
5. GOLF III Estate (1H5)
6. JETTA IV (162, 163, AV3, AV2)
7. JETTA VI (162, 163, AV3, AV2)
8. JETTA / CLASICO VI (162, 163, AV3, AV2)
9. BORA IV (162, 163, AV3, AV2)
10. BEETLE (5C1, 5C2)
11. FUSCA (5C1, 5C2)
12. BJALLA (5C1, 5C2)
13. See more in applications

Principles of the wheel bake cylinder work

If you need to slow down or stop, the driver presses the brake pedal. The mechanical action comes to the vacuum amplifier. After the pressure in the first circuit has arisen, the first piston acts on the second. This creates pressure in the second circuit. The cavities that have been released in the working sections as a result of pressure are filled with brake fluid from the reservoir. The pressure in the circuits drives the working brake cylinders. The pistons of the working cylinders come out of the cavities and press the brake pad against the brake disc.

After reducing the speed to the required level or stopping the pistons, under the action of the return springs, return to their original position.