Natural rubber is acquired from the sap of rubber trees. Synthetic rubbers are man-made materials with similar properties. Fabric is used to give the tire strength.
Other materials that are used to make tires include carbon black, sulfur and chemicals, such as accelerators, softeners and antioxidants. Carbon black is the most important non-rubber material used in the manufacture of tires. It provides strength, abrasion resistance and UV protection. Sulfur is used to vulcanize the rubber, which makes the rubber stronger and more durable. Accelerators speed up the vulcanization process, while softeners make the rubber more flexible. Antioxidants protect the rubber from deteriorating over time.
Tires are made by a process called tire building. The first step in the tire-building process is to lay the fabric plies on a flat surface. The rubber tread strips are then applied over the fabric. Next, the tire is shaped in a tire-building machine. The beads, which are metal wires, are then inserted into the tire. The tire is then removed from the machine and inflated to its proper size.
After the tire has been inflated, it is put through a process called curing, where the tire is subjected to heat and pressure. This hardens the rubber and makes the tire more durable. The last steps in the tire-making process are to inspect the tire for defects, trim off any excess rubber, and mount the tire on a rim.
