Cast iron brake drum for car: cast iron
The scientific name of the brake hub is the brake drum, which is the main component of the drum brake system. The friction between the inner surface of the brake drum and the brake pads during the braking function. The brake drum is a cast iron piece shaped like a tambourine, which is fixed to the tire and rotates at the same speed.
High quality auto spare parts include brake system brake drum for European and American market,and also including Asia,middle-east market,south america in various quality;
Integral casting The brake drum is integrally cast from high-strength gray cast iron or alloy cast iron containing Cr. This brake drum has a simple structure, convenient processing, and large heat capacity, but has a large mass, and is mostly used for medium and heavy vehicles.
Combination of steel plate and cast iron The brake drum is composed of a steel plate stamped drum plate and a cast iron drum ring, which has a small mass and is mostly used for cars and light cars.
Combination of light alloy and cast iron The main body of the brake drum is a light alloy material (such as aluminum alloy), which is lined with a cast iron ring. This kind of brake drum is not only small in weight, but also good in heat dissipation, and is mostly used in cars.
The brake drum is an important component of the drum brake system. The inner surface of the brake drum of the drum brake is where the braking device generates a braking torque. With the same braking torque, the diameter of the brake drum of a drum brake device can be much smaller than that of a disc brake. Therefore, in order to obtain a powerful braking force, a large vehicle used for loading can only install a drum brake in a limited space of a rim. Drum brake systems are typically installed on the rear wheels of large vehicles.
The brake drum is improperly designed and will change easily when heated; the brake drum is not balanced and mechanical deformation will occur, which will cause poor contact between the shoe and the drum, resulting in increased pedal force and stroke; When it is large, it may cause self-locking and generate vibration and noise. Therefore, the brake drum should have sufficient wall thickness, and cast circumferential or axial stiffeners on the outer surface near the opening to improve strength. These stiffeners also play a role of heat dissipation, which can reduce the temperature of the friction surface, shorten the brake cooling time, and increase the energy capacity by 35% to 40%.
The working surface of the brake drum is generally finished after being assembled with the wheel hub by positioning the bearing holes. Mini cars require roundness and concentricity tolerances of the working surface ≤ 0.03mm, radial runout ≤ 0.05mm, and static imbalance ≤ 1.5N · cm.