Nowadays we have ring-shaped components on the wheels that we call tires. The purpose of the tire is to transfer vehicle’s load from the axle to the ground through the wheel. The second main purpose of the tire is to provide traction on the surface traveled over.
When the pneumatic tire is mounted on the wheel it supports the rim by two main aspects. First, tension in the cords pulls on the bead uniformly around the wheel, except where it is reduced above the contact patch. Transfer of the net force to the rim through the bead is the second aspect
Before rubber was developed, the first versions of tires were simply bands of metal fitted around wooden wheels to prevent wear and tear. Early rubber tires were solid (not pneumatic). Today many types of vehicles, including bicycles, motorcycles, cars, buses, trucks, heavy equipment, and aircraft use pneumatic tires. Railcars and locomotives still use metal tires. Various non-automotive applications, such as some casters, carts, lawnmowers, and wheelbarrows use solid rubber or other polymer tires.
Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures. When the tire rolls over rough features on the surface it also provides a flexible cushion that absorbs shock. To provide a bearing pressure that will not excessively deform the surface tires have a footprint that is designed to match the weight of the vehicle with the bearing strength of the surface that it rolls over. Natural rubber, fabric and wire, synthetic rubber along with carbon black and other chemical compounds are the main materials of today’s pneumatic tire. They consist of a tread and a body. The tread provides traction while the body provides containment for a quantity of compressed air.
The materials of modern pneumatic tires can be divided into two groups, the cords that make up the ply and the elastomer which encases them. The cords, which form the ply and bead and provide the tensile strength necessary to contain the inflation pressure, can be composed of steel, natural fibers such as cotton or silk, or synthetic fibers such as nylon or kevlar. Composed of steel, natural fibers such as cotton or silk, or synthetic fibers such as nylon or Kevlar, the cords form the ply and bead and provide the tensile strength necessary to contain the inflation pressure The key component of pneumatic tire design is the elastomer, used to form the tread and encase the cords protecting them from abrasion and holding them in place. Composed commonly of styrene-butadiene copolymer the elastomer consists of various composites of a rubber material with other chemical compounds such as silica and carbon black. To reduce fuel consumption in the transportation sector the rolling resistance in the elastomer material optimization is a key challenge.
