Just one glance at your car tire and you will assume that it is all rubber. Many people think so, albeit wrongly. You would however be very surprised to know that your car tires are not all rubber. They are part rubber, part cloth, part steel and part other materials.
This is the cross section of a car tire
Image source: http://en.wikipedia.org/wiki/Tire
A closer look will reveal that the car tire is more complex than you imagined it to be. Car tires come in different sizes depending on the type of car and the model. The constituents of car tyres are mostly the same but what will differ is the design. While some parts of the car tire are obvious and can be seen, some other parts cannot be seen but play an equally important role in helping the tires function and perform well. Many of the modern tires do not have tubes; instead, they have an inner lining that has replaced the tube. So what is a car tire made up of?
A car tire is made up of the following parts
- Tread
- Bead
- Belt
- Shoulder section
- Cap plies
- Body section
- Others
The tread
The tread is the part of the tire that comes into contact with the road. For this reason, treads have a rough surface engraved with different patterns so that they do not slide on the road. Treads are designed differently from one tire to another. The designs are constantly upgraded to give a firm grip on the ground even under different conditions.
Bead
This part connects the rim of the car to the tire. It usually forms the section of the wall and is made up of a rubber core and beaded wire. Should this section collapse, the tire will be a write-off.
Belt
This ply is immediately below the treads. It is made up of steel and it enhances stability on the road and protects the tube from punctures.
Shoulder section
It is the part of the tire bordering the tread and the sidewall on the two sides of the tire. It helps in heat distribution to prevent the tire from burning up.
The body section
This is made up of two or more plies laid on each other. In most cases, polyester cord is the most used fabric for the plies. They are then coated with rubber so that they can blend easily with the rest of the tire. To gauge the sturdiness of a tire, one will determine that by the number of plies in the tire. In most cases however, car tires are made with two plies only.
This kind of wear is caused by under-inflation
Image source: http://en.wikipedia.org/wiki/Tire
Cap plies
These are mostly found in the performance tires. They are just extra layers of polyester that are used to reinforce all the other parts of the tire and ensure that even during heated runs, the tire holds together when the car is racing fast.
Wear bars
These are put on the bottom of the grooves to indicate the tire wear. If your tire wears down to them, then it means that you should get a new set. by the time your tire gets to these bars, it will have just about 1.6mm of tread remaining, very little indeed.
Different tires will be made differently. For example, performance tires have more reinforcement. Truck tires are made to carry heavy weights and so on. You should buy what best suits your situation.
