With the appearance of automobiles in 1895, pneumatic tires were widely developed. The first samples of automobile tires appeared in France in 1895. This was a single-tube tire made of plain canvas, although it had tread rubber but no pattern. In 1892, Brimeer in England invented the cord fabric, which was used for production in 1910. This achievement not only improved the tire quality and expanded the tire variety, but also made the outer tire possible to be molded. With the improvement of tire quality requirements, the quality of the cord has also been improved. The cotton cord was replaced by rayon. In the late 1950s, the rayon was replaced by nylon and polyester cords with better strength and higher heat resistance. With the development of radial tires, steel cord has strong competitiveness.
In highway transportation, there are two main situations where the tire pressure does not meet the safety requirements. One is that the tire pressure of a freight car is too high, and the other is that the tire pressure of a small car is too low. Both of these situations can easily lead to a flat tire in a moving car. As far as the 900-20 tires commonly used in freight cars are concerned, when the tire load is the maximum allowable value, the internal pressure of the tires is generally required to be seven atmospheres, and freight car drivers generally inflate the tire pressure to 7 atmospheres in order to load more cargo. More than 10 atmospheres, this situation makes the tire in an overloaded state for a long time, just like a balloon filled with too much gas, plus factors such as overloading and road bumps, it is easy to cause a tire blowout.
Car wheels and tires are the places that need to be inspected. During the self-driving tour, because the tires are in contact with the ground for the longest time and wear the most, they are the places that need to be inspected. If the tire is a radial tire, the sidewall is the weakest part, because the whole radial tire has no steel wire on the sidewall, so you must be very careful in use. If you drive at high speed on a section with poor road conditions when traveling, the tire may hit a deep pit or other foreign objects, which will cause serious extrusion deformation of the tire between the impact object and the rim flange, resulting in yarn breakage in the sidewall cord. The air inside the tire will push up from the broken yarn to form a bulge.
If you find a tire bulge, you should replace it in time, otherwise it is easy to cause a tire blowout when driving at high speed. Test the tire pressure to see if it is within the normal range. If it is not normal, it should be inflated and adjusted in time. How can we know that the tire should be replaced? Many riders know the importance of car tires, but they don't know when they should be replaced. If the tire "wear-resistant indicator" in the groove indicates that the depth of the groove is less than 1.6mm, then the tire should be replaced.
The tire wear indicator mark is the protrusion in the groove, and when the tread is worn to 1.6mm, it will be flush with the tread. If you use a tire with a remaining groove depth of less than 1.6 mm, there will be a sudden loss of traction and braking force in rainy days, and there may even be no traction in snowy days. If the tire is replaced before the tire wears down to 1.6mm, there should be no above problems.
In snowy areas, in deep snow, the tire tread should have the ability to compact and throw the snow out of it. Therefore, it is wise to replace the tires before they wear out to this limit.