Some people said that the development of the world automobile industry cannot be separated from the revolution of automobile tires. The invention of the radial truck tyre in 1946 by Michelin Tyre Company brought an epoch-making revolution to the tyre field. The advent of the radial truck tyres not only has a decisive impact on modern transportation, but also brings bright colors to human life. Up to now, it has occupied the absolute mainstream of domestic and foreign tyre markets.
The plies of the radial truck tyre are arranged at an angle of 90° or about 90° with the center line of tyre treads, which is consistent with the radial planes of the ply tyre. It is very similar to the meridian on earth, so it is also called the radial truck tyre. This arrangement of the plies contributes to a 40%-50% decrease in ply amount of the radial truck tyre compared with the ordinary bias tyre. The radial truck tyre is only connected by rubber in the circumferential direction. Therefore, it has a belt layer similar to a buffer belt that has a large angle between several ply lines and radial planes（the included angle is 70-75), high strength and low extension for withstanding the large tangential force that generated during driving and improving the rigidity of tyres. The belt layer is usually made of fabric cords (such as glass fibers, polyamide fibers) or steel cords with high strength and small tensile deformation.
The simple way to distinguish the tire specification is by the code. For example: 185/60 R 15 84 H is a code of tyres, and "R" stands for the radial truck tyre.