Tire marking refers to the production number, manufacturer's trademark, size specification, layer, maximum load and corresponding air pressure, Chinese pinyin code of the carcass cord, and installation on both sides of the tire according to national standards. requirements and driving direction signs, etc.

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 cord tire.

The side of the tire is marked with symbols such as "△", "-", "□" or words such as "W" and "D", indicating the lightest part of the tire. When installing the inner tube, it should be The valve is installed in alignment with the mark to even out the weight around the tire and keep the tire stable when rotating at high speed. The arrow "" indicates directional tires. Install in the direction of the arrow for rotation.

High-pressure tires are represented by D5B, D represents the nominal outer diameter of the tire, and B is the cross-sectional width of the tire in inches. "X" indicates high-pressure tires.

Low-pressure tires are represented by B-d, B is the tire section width, d is the rim diameter, and "-" represents low-pressure tires. Since section B is approximately equal to section height H, the size d of the installed rim can be calculated as d=D-2B. For example, Audi cars use tires of the 185/80R1490S type.

Tire section width and height ratio (aspect ratio) are two important indicators for describing tire size.

The tire section width refers to the maximum distance between the two outer sides of the tire after it is inflated according to regulations. It is generally divided into units of 5mm, but the section width tolerance of new tires is 63%. Sectional height refers to half the difference between the outer diameter of the tire and the nominal diameter of the rim after the tire is inflated. The tire aspect ratio (H/B) is the ratio of the tire section height H to the section width B, expressed as a fraction after the diameter is rounded. Generally it is a multiple of 5. For example, car radial tires are divided into 60, 65, 70, 75 and 80 series. The graph below shows the maximum driving speed for different tire constructions.

Tire structure speed level Maximum driving speed of tires with different nominal diameters (hm/h)

10 12 /13

120 135 150

< p>Radial tires Q 135, 145, 160

Radial tires S 150, 165, 180

Radial tires H-595 210

Diversified foreign tire specifications , China's tire specification marks are mainly divided into imperial and metric specification marks.

Imperial specification mark

Generally, this mark is used for ordinary section truck tires and bias ply tires for cars. It is mainly expressed as the following part.

A Nominal section width of tire, unit is in

B Tire structure mark

C Nominal diameter of rim, unit is in

D Layer

The structural mark of radial tires is represented by "R", and the structural mark of bias tires is represented by "-". The ply refers to the specific strength mark of the tire withstanding the maximum load. It does not necessarily represent the actual number of ply layers. For example, a 9.00 specification 12-ply tire can have several actual ply numbers, but the maximum load is 2050kg.

Metric specification mark

Generally, radial car tires use this representation, which includes the following content:

A The nominal section width of the tire, in mm

B Nominal tire aspect ratio

C Speed ??symbol

D Tire structure symbol

E Nominal rim diameter in inch

< p>The nominal aspect ratio of the tire refers to the ratio of the cross-sectional height to the cross-sectional width of the tire installed on the theoretical rim.