Do Tires Have Metal In Them?

‍Internal Structure of a Tire

Tires are built to withstand plenty of weight and loads, on a cushion of air. Also, they have to maintain decent contact with the road surface, while providing adequate grip and traction. To achieve all these goals, tires have to be solidly built, using a combination of the right materials. Let’s take a closer look at the different parts that make up a tire’s structure.

Plies

Plies form a tire’s basic structure. They usually feature polyester and a combination of other fiber cords, which have been wound together. These materials are normally sandwiched between different rubber layers.

Tires contain two types of plies. These are radial plies and bias plies. Radial plies are positioned perpendicular to the tire’s spin, thus their name. Bias-plies, on the other hand, run at overlapping angles.

Tire manufacturers use fiber cords to form the plies since they are quite flexible. However, these cords are inelastic. As a result, the tire will be able to flex without losing shape or deforming under pressure.

Sharp objects and abrasive elements can cut or damage plies. And when this happens, the tire’s rubber will not be able to withstand high air pressure, and the tire will need to be replaced.

Steel Belts

Steel or belts are positioned circumferentially around the tire’s circle. As their name suggests, they are made of high-quality, thin steel wires, which have been woven together to form thick cords. The cords are then woven together to form large braided steel sheets.

Just like the fiber cords, the steel sheets are also sandwiched between the rubber layers used to make the tire. Most of the passenger touring tires on the market come with around two to three steel belts.

Cap Piles

Cap piles are usually placed above the steel belts. Their structure resembles that of steel belts. The only difference is that they are made of woven fibers. Kevlar and nylon are the two most popular fibers used to make the cap piles.

Cap piles play a vital role in helping to maintain the tire’s shape. Also, they help to enhance its stability at high speed. Hence, the number of cap piles present in a tire will depend on the tire’s speed rating.

Most modern tires now feature jointless cap piles and steel belts. With this design, the cap piles and steel belts are seamlessly connected or woven together, as opposed to the traditional method, which entails clamping them together.

Tires with the jointless construction method tend to eliminate the roundness irregularity that older tires come with, resulting in smoother-running tires. Also, tires that feature this method also tend to deliver better fuel efficiency, compared to the older ones with the jointed construction.

Beads

Beads refer to the part of the tire that holds it to the rim. They are usually made of brass and copper. Some tire manufacturers also use bronze-plated high-tensile steel wires. Beads play an important role in keeping the tire firmly attached to the wheel especially when it’s rolling.

The Exterior of a Tire

Now that you have an idea of a tire’s internal construction and the different materials that make up its structure, we will now take a closer look at its exterior. Here are the different parts that form a tire’s exterior.

Sidewall

As its name suggests, sidewalls form the sides of a tire. Sidewalls are made of a sturdy rubber compound, designed to resist damage that may be caused by cuts, snags, and ozone damage. The tire’s information is usually printed on the sidewall, This may include details like speed rating, load index and size.

Tread

The tread is the part of the tire, which comes into contact with the surface. A tire’s tread compound as well as the design will have to balance traction, wear, handling, rolling resistance, and fuel economy.

Also, the tread compound and design will determine the tire’s application. For instance, winter tires will have a different tread compound than summer or all-season tires. At the same time, all-terrain tires will have a different tread design, compared to all-season tires.

Grooves and Sipes

A tire’s tread area is usually separated into different tread blocks. And this is usually done by grooves. Grooves form deep channels on the tire. These grooves help to evacuate water from the tire’s tread area, thus helping to prevent aquaplaning.

If you take a closer look at a tire’s tread, you will notice it has a series of small cuts on the tread blocks. These are known as sipes. Sipes help the tire’s tread blocks to both flex and suck up water. They also provide additional biting edges for a tire, especially on ice-covered and snow-covered roads.  

Wrapping It Up

As you can see, different types of metal in different areas. The metal used in a tire plays vital role in providing solidity, stability and sturdiness. And as a result, the tire will be able to handle heavy loads without deforming.