As the only part that touches the ground, tires provide not only lateral and longitudinal grip, but also shock absorption and impact resistance. From the appearance, the tires are all rubber products. But in fact now the tire is a high-tech products, including a variety of advanced technology and complex structure. Let us understand the basic structure of the tire and how to properly use the tire.

Structure analysis of tires:

The cross section structure of tire can be divided into four parts: tread, shoulder, edge and ring. Each part has its own function. Tread mainly contact with the ground, tire shoulder and edge play a supporting role, tire ring and wheel ring contact play a sealing role.

The tire is not just a mass of rubber, the tire is actually composed of multiple layers of different materials superimposed together -- tread pattern, covering layer, steel wire bundle layer (2 layers), stress absorption rubber strip, tire cord fabric layer, air tightness layer. First of all, we talk about the "steel belt bundle layer", this layer is made of two layers of steel wire layer, the steel wire of two layers of steel wire layer into a certain Angle, the role is to improve the tread rigidity, so that the tires can cope with uneven road impact. In order to prevent corrosion of the steel wire, there will be a "covering layer" outside the steel wire layer. "Tire body cord layer" runs through the section of the entire tire, providing support for the tire. The "air tight layer" is located inside the tire and extends to the tire ring position.

As for the commonly heard aspect ratio, we can clearly understand how each parameter is obtained from the diagram above. The smaller the aspect ratio, the thinner the tires look. The small aspect ratio of tires is the trend, the reason for which is to adapt to the high torque output of new models of cars.

For the general user, we only need to care about the tire size parameters in terms of tire identification. For example :225/40 R17 94Y, 225/40 refers to the aspect ratio (also called flat ratio), R refers to the radial tire, 17 refers to the outer diameter of wheel rim, 94 refers to the load index, and Y refers to the speed grade. The specific values of load index and speed class can be obtained from the relevant tables.