Automobile Tyres / Tires

Tyre is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground.

A tyre is a cushion provider with an automobile wheel. It consists of mainly the outer cover i.e. the tyre and the tube inside. The tyre-tube assembly is mounted over the wheel rim. It is the air inside the tube that carriers the entire load and provides the cushion.

Tyres play a very important role in the running of an automobile. In fact, tyres are the components in a vehicle which are in constant contact with the travel surface. They experience the road shocks first before they are absorbed and damped by the suspension. It can be said that tyres, being flexible members absorb some portion of the road shocks and impact loads before the loads reach the actual suspension system. [1]

Tyres have to possess two contradictory qualities. They have to be strong, hard and rigid to be able to resist all the loads corning on the vehicle. On the other hand, they have to be flexible to produce cushioning effect in the first place to avoid a rough ride. [1]

The tyre performs the following functions  [1]

1. Supports the vehicle load
2. Provides cushion against shocks
3. Transmits driving and braking force to the road
4. Provides cornering power for smooth steering

A tyre is made of three basic elements viz. thread, body and beads. These elements are composed of three incompatible materials - rubber, fabric and steel. The tread is meant to take load, the beads provide a firm footing for the tyre one, the rim and the body is a joining link between tread and the beads. The constructional detail / skeleton of a typical heavy-duty vehicle is as shown in figure below.

Radial-tyre (Heavy-duty)_Bridgestone Americas

A tyre tread’s design is composed of five basic elements; tread blocks, grooves, sipes, cross slots and ribs. And have different thread patterns according to the purpose of application or use. To know more about tyre thread pattern, we discuss on the article "Tyre thread patterns or design" to learn more.

The fundamental materials of modern tyres are synthetic rubber, natural rubber, fabric and wire, along with other compound chemicals. They consist of a tread and a body. The tread provides traction while the body ensures support. [2]

Tyres are made up of a naturally white rubber in which carbon black (pigment) is added to increase the strength and durability of the rubber. It also resists hot spots on the tyres. Also, tyres constitute various metals such as titanium and cobalt along with fabrics such as nylon, rayon, and polyester. [2]

Generally, there are two major types of tyre we well known, they are; tyre with tube, and Tubeless tyre. But according to manufacturing methods (or type of ply fabric layout/construction), tyres have much more complex element and their versions are Cross-ply or Bais angle, Bais belted ply, and Radial ply construction tyres.

Next Article: "Types of Tyres"

Feature Post: "Tyre Construction and Constitutes"

References:

[1] Automobile Engineering By Kamaraju Ramakrishna.

[2] Trade of Motor Mechanic: Module 7: Unit 1: “Wheels & Tyres” by SOLAS, In cooperation with: Subject Matter Experts; Martin McMahon & CDX Global Curriculum Revision 2.2 16-01-07 © SOLAS 2013.