The small iron block on the wheel hub of a car is the tire balance block. Tire balance block is a counterweight component installed on the wheel of a vehicle. The function of the balance weight is to keep the wheels in dynamic balance at high speed. In the case of static and low-speed rotation, uneven mass will affect the stability of object rotation. The higher the rotating speed, the greater the vibration. The function of the counterweight is to reduce the mass gap of the wheel as much as possible and achieve a relatively balanced state.

The wheel of a car is a whole composed of tires and wheels. However, due to manufacturing reasons, the mass distribution of all parts of the whole can not be very uniform. When the automobile wheels rotate at high speed, it will form a dynamic imbalance state, which will cause wheel jitter and steering wheel vibration when the vehicle is running.

In order to avoid or eliminate this phenomenon, it is necessary to correct the balance of each edge part of the wheel by adding counterweight under dynamic conditions. This correction process is usually called dynamic balance. That is, what is usually called adding a balance weight; Made of lead alloy, there are 5g,10g,15g, etc. Don't think that the weight is small, and the wheel will produce great centrifugal force when it rotates at high speed. There is a steel hook on the counterweight, which can be embedded on the rim.

Extended data:

Tires should be regularly checked for dynamic balance and checked with a dynamic balance tester. Wheel balance can be divided into dynamic balance and static balance. Dynamic imbalance will make the wheels shake and make the tires wear in waves; Static imbalance can cause bumps and jumps, which often leads to flat spots on tires. Therefore, checking the balance regularly can not only prolong the service life of tires, but also improve the stability of cars when driving, and avoid traffic accidents caused by the tire swinging, jumping and out of control when driving at high speed.

Need to do dynamic balance.

1, after replacing a new tire or repairing a collision accident;

2. Unilateral eccentric wear of front and rear tires;

3. The steering wheel is too heavy or floats and shakes when driving;

4. When going straight, the car deviates to the left or right;

Although there is no such situation, for the purpose of maintenance, it is suggested that the new car should be driven for three months, once every six months or ten thousand kilometers.

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