1. When can tires be mended and when can they not be mended?

If the front tread of the tire is punctured, and only one place is punctured, and the wound area is less than 6 mm, in this case, the tire can be repaired. If the tire sidewall or shoulder area is punctured, it is not recommended to repair the tire. It is best to change the tires directly.

Automobile tire is composed of several parts, the main visible parts are tread, shoulder, sidewall and bead, and the interior is composed of nylon crown belt, steel belt, cord and airtight layer in turn from outside to inside, and the functions of each part are unique.

1. The sidewall is the most fragile area on the tire surface, which is mainly used for supporting the tire and damping. When the car is running, the tire wall is stressed heavily, but it is generally thin, lacking the protection of nylon crown belt and steel wire belt.

Therefore, if the tire wall is punctured, it can be repaired, but once it is subjected to a large load, it is easy to cause the original mouth surface to rupture and leak. If the load is too large, it may be deformed by the standing wave when the situation is serious, and then the tire will burst, which is very dangerous.

2. The shoulder is the part connecting the tread and the sidewall, which is what we call the tire tread edge area. In the scene of cornering and extreme driving, the shoulder needs to land, and its design directly affects the handling performance of the car to some extent. This part is also the stress area. Similar to tread, it is not recommended to repair a flat tire.

If the tire is bulging, don't mend it. When the tire is strongly impacted during driving, the impact object and rim will easily cause the sidewall cord to break, and the air pressure inside the tire will lift the tread from the broken cord. This process is irreversible, that is, the tire can not return to normal, thus forming a bulge, which is a potential puncture hazard.

4. When the service life of tires reaches the limit, new tires need to be replaced.

With the increase of time and driving distance, the tread rubber gradually ages, and the tread becomes thinner and thinner due to wear. If the tire pattern or tread cracks or reaches the "wear mark", it is time to replace the tire.

Remarks: "Wear limit sign" is generally located at the bottom of the groove of tread pattern, and the protruding part inside is the wear limit sign. Generally speaking, new tires can be used for 4-6 years or driven for about 40-70 thousand kilometers under normal vehicle environment, depending on the quality, performance, driving habits and vehicle environment of the tires.

Second, the common methods and means of tire repair

1, rubber strip tire repair

This method does not need to disassemble the car tires. First find the punctured place, take out the hard object, and insert the tire patch into the wound with a conical file to make it closely combine with the tread.

Then the taper file is pulled out, and the excess tape can be cleaned or not, which is quick, convenient and time-saving. Every day, car owners can prepare a set of simple tools for quick repair in case of emergency.

This is a simple and quick way to mend tires. For example, if a tire is punctured by a small nail, it can be used temporarily and urgently. This method is not recommended if the wound area is slightly larger. Under the action of large extrusion pressure, it is easy to leak air again or enter water for a long time, which is not durable.

2, cold tire repair

The cold patch tire needs to be disassembled first, and then the airtight layer on the inner wall of the tire should be properly polished to make the airtight layer slightly rough. Then, a special cold patch adhesive is coated on the polished airtight layer, and then a cold patch film is attached, so that the cold patch film and the tire airtight layer are closely attached together with tools.

Cold patching is relatively fast, cheap and no problem in daily use, but it is not recommended to use this method in the case of a slightly larger wound area, and its durability is not as good as hot patching and mushroom nails.

3. Hot tire repair

The method of hot patching is similar to that of cold patching, except that a special hot patching film is used, which requires a little more procedures and needs to be polished to the steel wire layer. The hot repair tool is used to heat the film and make it closely combined with the tire airtight layer and steel wire layer.

This tire repair method is completely durable, and there is basically no need to worry about air leakage. This is one of the commonly used tire repair methods in many auto repair shops, but it requires a certain skill and experience of the tire repair master, and the time and cost will naturally be slightly expensive.

4, mushroom nail tire repair

When you hear this name, you probably know its material, that is, the mushroom-shaped special patch. This tire patching method needs cold patching, and the airtight layer needs to be polished first, but it does not need to be polished to the steel wire layer, and then cold patching glue is used first.

After that, mushroom nails are installed from the inside out, so that the steel needles of the mushroom nails pass through the whole tire composite layer, and the outer side of the tire tread is clamped and pulled out with pliers to make it closely fit with the tire, and then the tool is used for running-in.

This kind of tire repair method can repair both inside and outside, and has the effect of repairing the tire airtight layer to the whole composite layer of tread, and the overall durability is good. Of course, the cost is higher than other methods.

To sum up, rubber strip tire repair is only suitable for emergency tire repair and is generally not recommended. Cold patching takes a short time and has high efficiency, but its durability is not as good as that of hot patching and mushroom nailing.

Last but not least, if the front wheel is patched, try to replace the patched tire on the rear wheel. Similarly, if it is a rear-drive vehicle, the repaired tire should be replaced at the front. At the same time, in order to ensure the stability of daily driving, it is best to calibrate the dynamic balance of the vehicle.

Third, how to choose household tires?

There are many kinds of tires, such as performance tires, silent tires, snow tires, off-road tires and so on. The tires of family cars mainly consider safety performance, wear resistance, comfort and economy. Generally, tires with good reputation in the market can basically meet the requirements, such as Pirelli, Michelin, Mapai, Bridgestone, Goodyear and Deng Lupu.

If there are too many vehicles in the city every day, the road environment is good, or you often run at high speed, and you need tires with comfortable and quiet performance preference, you can consider Michelin and Mabai, but their prices are slightly more expensive;

Pirelli and Bridgestone are slightly obvious in wear resistance, and Goodyear has good grip and wear resistance. If economy is considered and comprehensiveness is emphasized, Deng Lupu and Bridgestone can be considered, with moderate comprehensive performance such as wear resistance, silence and comfort.

Rubber tires have long service life. Considering the safety of the vehicle, it is necessary to replace a new tire after driving for 40-70 thousand kilometers or 4-6 years. Generally, new tires will age in different degrees after 3 years, and their service life will continue to decline.

The average life span is about 4-5 years, while the average annual mileage of family cars is about 1- 1.5 thousand kilometers, which means that the total mileage in four years has reached 50-60 thousand kilometers, and the wear resistance is basically negligible.

Fourth, how to deal with the puncture on the expressway?

First of all, I would like to say that puncture is rare, and it will only happen under certain circumstances, such as the tire itself aging and bulging, and the tire is strongly hit.

Under normal circumstances, tires will not burst easily. In daily driving, the tires are punctured by nails and hard objects on the road. In this case, the tire will not burst, and the gas inside the tire will slowly leak. There is a time course for air leakage, and the tire will not deflate immediately. Of course, according to the puncture area and other conditions.

Therefore, in daily driving, you don't have to worry about flat tires. If you have a flat tire under special circumstances, don't panic at first. Grasp the direction with both hands, step on the brakes appropriately to slow down, and remember not to hit the direction in a hurry and stop stepping on the brakes.

Nowadays, cars are generally equipped with ESP and ABS systems. What we need to do is to correct the direction moderately, then observe the road conditions, turn on the double flash and drive to the emergency lane to stop.

On the expressway, you can stop in the emergency lane to refuel or replace the spare tire without affecting other vehicles and ensuring your own safety, but you need to take safety measures to avoid being penalized.

For example, if the vehicle stops in the emergency lane, try to get close to the guardrail, turn on the double flashing, put a triangle warning sign at the appropriate position behind the vehicle 150 meters, and evacuate other personnel to a safe area outside the guardrail.

When replacing the spare tire, people and things should not exceed the emergency lane line, and it should not affect the coming car. Replace the left wheel, because it is close to the carriageway, which is risky. Be sure to pay more attention and try to find a place with broad vision and good road conditions to replace the spare tire.

After a flat tire, it will affect the direction and the vehicle will run off. Nowadays, cars generally have body stabilization functions such as ESP. At this time, the vehicle driving computer will automatically activate ESP to automatically correct the direction according to the data such as vehicle speed and directional force, and stabilize the vehicle body. If you slam the direction in the opposite direction and the direction is not corrected properly, it will be counterproductive and dangerous.

Similarly, vehicles generally have ABS system, which will start automatically in case of emergency. At this time, the vehicle will automatically brake according to the situation. If you step on the brakes again, it is easy to cause the wheels to lock. In addition, the vehicle inclines and deviates from the direction, which is prone to rollover and other dangers.

In a word, automobile tires are consumables, which directly affect driving safety. Therefore, it is necessary to pay close attention to the tire pressure or manually check the tire condition to eliminate hidden dangers.