Construction of the tyres:

You will certainly be aware of the fact that tyres do not just consist of rubber and nothing else. A very important factor for the safety of a tyre is its interior construction. The so-called fabric carcass is a mesh of steel wires, cotton and nylon, which is interlaced in such a way with the rubber that maximum stability, driving comfort and safety are guaranteed.

In principle, there are two different ways of construction: Construction of a diagonal ply tyre: this tyre is called diagonal ply because the individual cords of the substructure run diagonally with respect to the tread of the tyre and in a criss-cross pattern from bead to bead. The number of these fabric layers depends on the size and on the desired load-bearing capacity of the tyre.

Radial ply tyre: the construction of this tyre basically consists of 2 components. In the lower part, the cords of the carcass layers run the shortest way, meaning across (radial) from bead to bead. A stabilising steel belt encloses the relatively thin, elastic carcass. The belt in the upper part of the tyre consists of several layers of gummed steel mesh (hence the name steel belt tyre). The wires within these belt layers run in an acute angle to each other. This feature provides the tyres with stability, high-speed suitability and durability. In addition, further fabric layers are inlaid in different ways – depending on the application area of the tyre – in the flanks and on the topside of the tyre.

Today, nearly all passengers cars have wheels fitted with radial ply tyres in order to save fuel, permit higher speeds by increased road adhesion and improve the driving comfort. Diagonal ply tyres are used for vehicles with low maximum speed which have to carry heavy loads. The fabric carcasses of tyres are constructed in different ways depending on the intended application area of the tyres. Tyres for, say, racing cars contain a much higher portion of steel fabric within their carcasses compared to other tyres, in order to achieve higher stability.