Radial tire is a structural form of tire, which is different from bias tires, arched tires, pressure-regulated tires, etc. The international code for radial tires is "R", which means steel wire tires.
Tire structure
The structure of the radial steel tire: the carcass is composed of a layer of radial steel wire plies. The tread crown is fixed by multiple layers of steel wire belts, and the functions of the sidewall and tread pattern are relatively independent.
Tire cord arrangement direction
The layers of carcass cords are arranged parallel to each other in a radial direction, forming an angle of 90° circumferentially with the centerline of the crown. The stress on the radial tire belt cord caused by internal pressure is not uniform across the belt width. Since the edge end lines of the belt layer are not fixed, the initial stress in this part is equal to zero, while the center part reaches the maximum value. As the belt tightens the carcass, the carcass cord stress decreases and the crown center becomes the smallest.
Tire crown
The role of the belt layer is to restrain the circumferential deformation of the carcass. The angle of the steel cord is close to the circumferential direction, forming an angle of approximately 12° to 25° with the crown centerline in the circumferential direction. Because the belt cords are arranged almost circumferentially, their length remains virtually constant. Therefore, the belt determines the shape of the tire and the initial stresses in the tire components caused by internal pressure. Withstand stress 60%~75%.
