Radial Tires, Construction

Cross-Section of a Radial Tire 

Fig 1: Identifying Cross-Section Of A Radial Tire

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

1. Tread Block 
2. Tread Groove 
3. Tread 
4. Nylon Ply 
5. Belt Layers 
   • Consists mostly of steel.
6. Bead Bundle 
   • Consists of steel wires vulcanized into rubber.
   • Make sure secure seating of the tire on the rim.
7. Bead Filler 
8. Wheel Flange Protection 
   • Protects the rim and tire from abrasion due to, for example, contact with the curb.
   • Tires with flange protection are designated by the abbreviation MFS.

The nylon ply -4-, belt layers -5-, bead bundle -6- and bead filler -7- form the carcass. The carcass is the "load-bearing structure" of the tire.