The cords of bias tires are arranged diagonally across, hence the name. It is characterized by high strength of the tread and sidewalls, but the sidewalls have greater rigidity and poor comfort. Due to the large movement and friction between the plies at high speeds, they are not suitable for high-speed driving. With the continuous improvement of radial tires, bias tires will basically be eliminated. The cord arrangement direction of a radial tire is consistent with the tire meridian section, and its ply is equivalent to the basic skeleton of the tire. Because the tires have to withstand greater tangential forces during driving, in order to ensure the stability of the cord, there are several layers of belt layers (also called tightening layers) made of high-strength, non-stretchable materials on the outside. , The cord direction and the meridian section present a larger angle of intersection. In terms of design, bias tires have many limitations. For example, due to the strong friction of the crossed cords, the carcass is prone to heat, which accelerates the wear of the tread pattern, and its cord layout cannot provide excellent quality. The maneuverability and comfort of the radial tire; the steel belt in the radial tire has better flexibility to adapt to the irregular impact of the road surface, and it is durable. Its cord structure also means that it is smaller than the diagonal line in the car. Much more friction, so as to obtain a longer tire tread service life and better fuel economy. At the same time, the characteristics of radial tires make it possible to have tubeless tires. Tubeless tires have a recognized advantage, that is, when the tire is punctured, it does not burst like a bias tire with an inner tube (which is very dangerous), but allows the tire to maintain air pressure for a period of time, which increases the car Driving safety. In addition, compared with bias tires, radial tires have better grip. Compared with ordinary diagonal tires, radial tires have greater elasticity, good abrasion resistance, low rolling resistance, good adhesion, good cushioning performance, large load-bearing capacity, and are not easy to puncture; the disadvantage is that the sidewall is easy to crack due to large lateral deformation. , Resulting in slightly worse lateral stability of the car, high manufacturing technology requirements, and high cost.
