Let's talk about the tire wear limit sign first. The tread pattern of each tire is marked with wear marks by rubber blocks or rubber belts. That is to say, the tread wear of the tire is close to the wear mark. Theoretically, when the tire is worn to about 4 mm, it should be replaced. Of course, some over-standard points in actual use are not a problem, but they must not exceed the standard. Let me start with three "T" indicators. The so-called 3t? The index has three words beginning with "T" on the tire side, Treadwear stands for wear resistance index, Traction stands for traction performance and Temperature stands for temperature index. Among them, the wear index is a number, and the higher the number, the stronger the wear resistance. However, it should be noted that the stronger the wear resistance of the tire, the lower the grip performance.
So the wear resistance is not as high as possible. Traction performance is the level of grip strength. It is classified as aa/a/b/C. AA is excellent, C is the highest grade, and C is the lowest grade. The temperature index is also classified as a/b/C, where A indicates that the tire has the strongest high temperature resistance, and B and C are the worst. When the vehicle is running, the friction temperature between the tire and the ground increases obviously, so it is necessary to choose A-class tires. RADIAL, R in specification 225/45ZRF 18 is the abbreviation of radial, which means meridian. At present, domestic automobile tires are basically tubeless, and tubeless tires are also called vacuum tires.
In the specification of 225/45ZRF 18, the letter "Z" indicates that the tire speed grade is greater than W or Y, that is, the speed is greater than 240 km/h. The letter "F" refers to the "quick start", which refers to the tire that can still run under the condition of stopping running, that is, the tire used to supplement the running gas. In m? In s, "m" means mud, and "s" means snow. In snow, m? S means that tires can drive on snow. Where "245" represents the tire tread width of 245 mm. The flattening rate of "45" tire is 45%. According to these two figures, it can be calculated that the tire section height (thickness) is 24545% =110.25mm. "R" means that the tire is a radial tire. "18" means that the inner diameter of the tire is 18 inch. "96" indicates the load index of the tire, and "load index" indicates the maximum load (unit: kg), indicating the maximum weight that the tire can bear when it is normally inflated. The load grade indicates that the maximum load of the tire is 7 10 kg. "W" indicates the speed class and the maximum speed at which the tire can transmit the specified load under the specified conditions. The speed grade mark is SA37. The speed of this tire is 270 kilometers per hour.