The tire sidewall is a relatively fragile part of the tire. Some daily misconduct may cause side damage. Many articles say that the side-side damage should be replaced, but if the tire is damaged by a small injury, it can't be replaced by many owners. Then the sidewall damage should not be changed. What kind of damage can continue to be used?

All manufacturers do not recommend users to repair the tire sidewall. Taking Michelin as an example, their point of view is that after the tire sidewall is damaged, the carcass cord has been broken, and the tire has a bulging danger, so it is necessary to replace the new tire as soon as possible.

Although tire manufacturers do not recommend repairing the sidewalls, there is still a service for repairing the sidewalls. At present, the methods for repairing the sidewall are mainly cold-filled (stick rubber), hot-filled (hot-melt rubber) and mushroom nail repair.

The rubberized operation is simple and can repair large wounds, but it is not durable enough. After a long time, the rubber stuck on the wound will gradually fall off, and the wound will leak again.

The hot supplement is to attach a special rubber rubber to the wound, and then use the baking machine to bake the wound until the raw rubber and the tire are completely fitted. However, the heat supplement easily damages the ply in the tire, causing the consequences of collapse, which in turn increases the risk of tires. Therefore, hot supplement is not suitable for sidewall repair.

For some small sidewall wounds, there is still a repair value because there is no serious damage to the ply, for example, the sidewall is pierced by a sharp object. This type of perforation usually does not break the cord on the ply, which is equivalent to the case where the needle is passed through the sheet without damaging the curtain, so that it can be repaired.

For this small area of the sidewall wound, the professional tire service shop will use a tire-side special steel needle plug (commonly known as 'mushroom nail') for repair. The entire repair process takes about 7 minutes, and the price depends on the size of the tire and the material of the tire. The price ranges from 60 yuan to 200 yuan. The advantage of using a mushroom nail to repair the sidewall is that it can repair the inner liner and fill the carcass at the perforation to ensure a more durable repair.

If the tire is not leaking, the missing or cracked rubber in the shallow side of the sidewall can also be repaired. In this case, since the tire does not have a penetrating flaw, but the surface rubber is damaged, the sidewall rubber surface can be repaired by a heat compensation method.

The occurrence of the bulge on the sidewall is the result of severe breakage of the curtain cord inside the tire. When this happens, the tire has been sentenced to “death penalty” and there is no value for repairing. New tires must be replaced. If it is barely repaired, the repaired tire can only be a dangerous product that may have a puncture at any time.

The so-called 'severe damage' refers to the case where the sidewall rubber is completely cracked. Rubber cracking means that the inner layer of the tire, the ply, the protective layer and other structures have been completely destroyed, and the tire can only be scrapped.

Although it can be repaired when the sidewall damage is not serious, the repaired tire has lost its original durability and safety and cannot continue to be the main force. For safety reasons, this repaired tire on the sidewall can only be used as a spare tire.

It should be noted that when using the tires that have been repaired on the side of the tire as a spare tire, it is necessary to strictly control the speed of the vehicle (recommended to maintain the speed of 80km/h) to ensure safe driving.