|Rubber (Natural and synthetic)||38%|
|Fillers (Carbon black, silica, carbon chalk)||30%|
|Reinforcing materials (steel, rayon, nylon)||16%|
|Plasticizers (oils and resins)||10%|
|Chemicals for vulcanisation (sulphur, zinc oxide, various chemicals)||4%|
|Chemicals as antioxidents to counter ozone effects and material fatigue||1%|
Basic Overview of Tyre Building
Process Stages of Building a Modern Radial Tyre
The major steps in tyre manufacturing
Extrusion – Preparation of Treads and Sidewalls
Tyre Assembly Machine
Curing Press / Mould
Bead wires are set at the applicators. Bead joint has to be in the right place to avoid tyre imbalance.
Inner liner is set at the drum and rotated around the drum at one turn. The joint is cut with a hot knife. Inner liner is set end to end so that the diagonal cutting seam is at the top. The ends are joined manually.
Body Ply: Mounting
Cord ply ends are set at the drum and rotated around the drum at one turn. The cord is cut by hand with a join of 2-5 overlapping wires. The join is pressed carefully together at the edges.
Bead Wire Mounting and Turn-Up
Bead wire mounting and turn-up is done automatically. Bead wire applicators bring the beads to the carcass. Edges are turned up with bladders over the beads and stitched tightly.
Sidewall Mounting and Joining
Sidewall ends are set at the drum and rotated around the drum at one turn. Sidewall is set end to end and the seam is fastened together manually.
Steel belt tables go down on the drum automatically. Steel belt is joined by cutting it with a hot knife and setting the ends together.
Cap Ply: Mounting and Joining
The ends of the nylon cap ply, is set at the drum in the middle of the steel belts. Bandage is wound on top of the steel belts 1-2 times. The bandage is cut with scissors.
Tread is pulled onto the drum automatically. Tread is set end to end and joined automatically.
First and Second Stage Coupling
Carcass (1st stage) and tread (2nd stage) packages are joined automatically. The carcass is set at the flanges of the carcass drum, pressurised, fastened to the tread package and stitched together.
After building the green tyre it is transferred to the painting machine, where anti-blemish chemicals are applied.