the air pressure on the tire is marked on the side of the tire. The air pressure mark on the tire only says the limit value that cannot be exceeded, for example, generally it does not exceed 34KPA, which is 3.4BAR.

Tire identification means that the production number, manufacturer's trademark, size and specification, grade, maximum load and corresponding air pressure, Chinese phonetic code of carcass cord fabric, installation requirements and driving direction marks should be marked on both sides of the tire according to national standards.

characteristics of main parts of tire

(1) toe

The rigid part used to fix the tire on the rim but not easy to stretch is called toe, which can firmly fix the tire on the rim and resist the force that makes the tire separate from the rim when the vehicle is running. In order to make the toe stable and form a rigid transition from the bead to the sidewall, the triangle rubber used for filling has a large hardness and is not vulcanizable, so the toe is irreparable.

(2) Sidewall

The rubber covering layer attached to the sidewall of the carcass to prevent the carcass from mechanical damage and other external effects (such as mud, water, etc.) is called sidewall. The difference between the sidewall and the tread is that it does not bear large stress and is not in contact with the ground, so it is not worn. The sidewall mainly works in a state of flexion and flexion, so the thickness of the sidewall can be slightly thinner. However, it must bear large mechanical deformation, and it is easy to crack under the action of ozone.

Therefore, the sidewall should have low tensile strength and excellent fatigue resistance and ozone resistance. Sidewall is the most prone to zipper puncture. Main reasons:

① insufficient air pressure. When radial tire is used after the tire is installed, the standard air pressure must be guaranteed. If the tire is deflated, the steel wire on the tire side will be excessively buckled and the steel wire structure will be loosened, and the pressure resistance will be reduced when it is inflated again, and a zipper puncture will occur.

② overload.

(3) Shoulder

Shoulder is located between the crown and sidewall and is the thickest part of the tire structure. It is also the part with the highest tire temperature when the vehicle is running, which is easy to cause rubber cracking. Such a wound should be checked and repaired in time to avoid the internal steel wire rusting caused by water seepage.

(4) Crown

The crown of the tire should be in direct contact with the road surface. Therefore, it has good wear resistance, low rolling resistance and noise, and excellent heat resistance and stab resistance. In addition, the tire crown bears a large load, especially on poor roads, so it must have good elasticity, fatigue resistance and high aging resistance.