Tyre identification[汽车修理知识]

According to national standards, the production number, manufacturer's mark, size specifications, level, maximum load and corresponding air pressure, carcass cord Hanyu Pinyin code, installation requirements and driving direction signs should be marked on both sides of the tire.
The carcass cord material is expressed in Chinese Pinyin.Such as M-cotton cord, R-rayon cord, N-nylon cord, G-steel cord, ZG-steel radial cordtire.
　　tireThe side is marked with symbols such as "△", "-", "□" or written with "W", "D" and other words, indicating the lightest part of the tire. InstallInner tube, Should beValveAlign the mouth with the symbol and install it to make the weight around the tire average and keep the tire stable when it rotates at high speed. For example, the arrow "" indicates a directional tire. Install in the direction of the arrow as the direction of rotation.
High-pressure tires are represented by D5B, where D represents the nominal outer diameter of the tire, and B is the cross-sectional width of the tire, in inches. "X" stands for high-pressure tires.
Low-pressure tires are represented by Bd, B is the tire section width, d is the rim diameter, and "-" represents low-pressure tires. Since the section B is approximately equal to the section height H, the installed rim size d can be calculated as d=D-2B. For example, Audi cars use tires of type 185/80R1490S.
Tire section width and height ratio (aspect ratio) are two important indicators to describe tire size.
The cross-sectional width of the tire refers to the maximum distance between the two outer sides after the tire is inflated according to the regulations. It is generally divided by 5mm as a unit, but the cross-sectional width tolerance of the new tire is 63%. The section width refers to the half of the difference between the outer diameter of the tire and the nominal diameter of the rim after the tire is inflated. Tire aspect ratio (H/B) is the ratio of tire section height H to section width B, expressed as a fraction after the diameter is rounded. Generally it is a multiple of 54. For example, car radial tires are divided into 60, 65, 70, 75, and 80 series. The figure below shows the maximum travel speed of different tire structures.
Tire structure Speed ​​level The maximum driving speed of tires with different nominal diameters (hm/h)

Tire structure Speed ​​level Maximum driving speed of tires with different nominal diameters (hm/h) 10 12 /13 　 　 120 135 150 Radial tire Q 135 145 160 Radial tire S 150 165 180 Radial tire H - 595 210

The specifications of foreign tires are diversified, and the specifications of Chinese tires are mainly divided into British and metric specifications.