(1) The tire has good wear resistance and high mileage
The crown parts of radial tires are all made of high-performance steel cords as the skeleton material, the rigidity is increased, and the mobility of the tread is relatively reduced when the ground is on the ground. Well, the mileage is high.
(2), small rolling resistance, low heat generation, fuel saving
The carcass of the radial tire is radially arranged, and the cords with high strength and good rigidity are used to fully exert the function of the tire under load. When the tire is rolling and deformed, the carcass is not subjected to high shear deformation like the multi-layer ply of the bias tire, and the stress and strain at the crown part are much smaller than that of the bias tire. Therefore, the hysteresis loss caused by internal friction is greatly reduced, the slippage during rotation is reduced, the heat generation is low, and the rolling circumference is large at the same time, which reduces the fuel consumption of the car.
(3), large turning ability
The carcass of radial tires is radially arranged, with high rigidity, and the ability to withstand lateral force is improved. The size of lateral force is also related to the material of the belt layer. The selection of steel cord can increase by 70%.
(4), can drive at high speed
Without the revolution of automobile tires, there would be no development of the world automobile industry, and the revolution brought to the field of tires by the radial tire invented by Michelin in 1946 was epoch-making. The advent of radial tires not only had a decisive impact on modern transportation, but also brought bright colors to human life.
First of all, from the perspective of speed, the speed of a car mainly depends on the engine, and the tires shoulder the sacred responsibility of completing this mission. Lewis, the famous American sprinter, his own quality is like the engine of a car, and the sports shoes on his feet are like the radial tires of the car. If Lewis wears ordinary leather shoes instead of sports shoes, then others will not take doping Also run faster than him. Although this is a joke, it illustrates the importance of radial tires in improving the speed of cars.
You may have seen pieces of rubber thrown off the tires on the road. This situation is caused by the accumulation of a large amount of heat inside the tires because the driving speed of the tires exceeds its critical speed. So, what is the relationship between speed and glue rejection? Before introducing their relationship, let me first introduce a phenomenon that occurs when tires are running at high speeds – “standing waves”.
When the tire is running, the contact part between the tire and the ground bends due to the load. When the tire rotates away from the ground, the curved part returns to its original shape with the pressure inside the tire. However, if the tire pressure is insufficient or the speed is too fast, the curved part will not have time to return to its original shape, and the tire will produce wavy deformation near the rear semicircle of the tire and the ground contact, commonly known as “standing wave”. When the “standing wave” occurs, the rolling resistance of the tire rises sharply, and the tire absorbs standing wave energy in a short time, causing the temperature to rise sharply. At this time, if you continue to drive at a high speed, the phenomenon that the tread rubber mentioned above will be thrown off will occur, which in turn will cause the tire to burst.
It can be seen from the above analysis that “speed-standing wave-heating-degumming-burst” is a line connected together. The radial tire has a strong belt layer outside the ply, so even when it rotates at high speed, it is not easy to have a “standing wave” phenomenon, so the radial tire can run at high speed, but the bias tire cannot. But everything has its limit, especially tires. Because the critical speed of the tire has been specified when it is designed and produced (of course, the speed of the tire of this structure is much higher than that of the bias tire). If the driving speed exceeds the critical speed of the tire, the above situation will also occur. Therefore, every driver should know the speed level of the tires used in his car and drive in strict accordance with the specified level, so as to avoid the occurrence of tire blowout and rollover accidents as much as possible.
(5), not easy to be punctured
Because the crown part of the radial tire has a belt layer, it is not easy to be punctured by sharp and hard objects such as iron nails (relatively speaking). Experiments have proved that to drive a nail with a diameter of 2mm from the tread, only 196N of force can be penetrated by bias tires, while 980N of force can be penetrated by radial steel wire tires. That is to say, comparing steel wire radial tires with bias tires, the steel wire radial tires that drive the same nails into the tread require 5 times as much force as bias tires.
(6), strong safety performance
The tread of radial tires is generally relatively wide, so it has strong grip, good braking performance, and good handling and stability. In addition, it has been introduced earlier that temperature is a major cause of tire problems, and radial tires have low temperature rise and fast heat dissipation during driving because of their thin sidewalls. Under normal circumstances, the temperature of radial tires is 100°C when they are continuously driven at a speed of 110km/h, while the temperature of bias tires is as high as 120°C when they are continuously driven at a speed of 69km/h. So radial tires can run on the highway safely and at high speed. In addition, radial tires also have notable features such as soft sidewalls, good shock absorption, comfortable riding, and low noise.
Tests have shown that compared with bias tires, radial tires have improved wear resistance by 50% to 100%, lower rolling resistance by about 30%, saved fuel by 8% to 10%, increased traction capacity by 10% to 20%, and improved lateral force. 50% to 70%, the puncture resistance is 5 times that of bias tires. However, because the sidewalls of radial tires are thinner, they are not as resistant to impact as those of bias-ply tires. The curbs and gravel can easily cut the sidewalls, causing the tires to be fatally injured and scrapped. In addition, due to the complex production process of radial tires, strict production technology requirements, advanced equipment and various expensive raw materials, the production efficiency of radial tires is not as high as that of bias tires, and the price is more expensive. Even so, along with the continuous development of highways, radial tires have become more and more popular among drivers. At present, Western Europe has fully realized the radialization of tires, the United States has reached 89%, and Japan has reached 78%. In most countries such as my country, the radialization of tires has also reached about 30%. It can be expected that with the passage of time, the proportion of radialization of tires will increase, and it is only a matter of time before all radialization is achieved.