Why Do Tire Sidewalls Bulge?
4 Answers
Tire sidewalls bulge because one or more steel wires inside the tire have broken, causing the rubber to be unable to withstand the internal pressure of the tire, leading to bulging. It is necessary to replace the tire promptly to prevent continued use from resulting in a tire blowout. Tires are circular elastic rubber products assembled on various vehicles or machinery to roll on the ground, mounted on metal rims to support the vehicle body. The maintenance methods for tires are: 1. Avoid curbs and potholes to prevent the sidewall cords from breaking and causing tire bulging; 2. Regularly remove debris from the tread to avoid blowouts; 3. Check the tire wear and replace them in time; 4. Regularly check the tire pressure, which should not be too high or too low.
Last time I got my car repaired, I noticed a bulging tire. A sidewall bulge is mainly caused by damage to the tire's carcass layers. Inside the tire, there are multiple layers of carcass fabric, which act like the skeleton supporting the entire tire. If you accidentally drive quickly over potholes or hit a curb, the sidewall of the tire can be instantly compressed, causing the inner cords to break. When this happens, the rubber loses its support and bulges outward under air pressure. Another scenario is prolonged underinflation, where excessive tire deformation causes the cords to repeatedly bend and eventually fatigue and break. Once, during an inspection, I found a bulging tire and had to replace it immediately because it could have burst at high speeds, which is extremely dangerous. It's better to slow down when driving on bumpy roads, and checking tire pressure monthly can help prevent such issues.
I've had personal experience with tire bulging, which is mostly caused by external impacts. The sidewalls of tires are particularly thin, and their strength mainly relies on the internal cross-woven cord layers. If you drive too aggressively, such as going over speed bumps at high speed or scraping against curbs while parallel parking, the impact on the side can break the cords. This is especially true for low-profile performance tires, which have a higher risk of bulging. Last time, the tire on my car bulged because I didn't pay attention while parking and the wheel tilted onto the sidewalk. Additionally, as tires age, the rubber becomes harder and more brittle, making them more prone to bulging when encountering bumps. So, when parking, make sure the tire is facing straight and avoid scraping the sidewalls. If you notice a bulge, replace the tire immediately—don't risk a blowout to save a little money. Regularly checking tire condition is really important.
There are two common causes of tire bulges: severe impact or prolonged low tire pressure. The sidewall of a tire contains layers of cords, and a severe impact can cause these cords to break, leading to a bulge in the rubber. When tire pressure is too low, the tire deforms excessively, and prolonged bending can fatigue and break the cords. Additionally, aging tires can become hard and lose flexibility. A bulging tire must not be used further as it poses a risk of blowout. Replacing the tire promptly is the only safe option.
