1. Automobile
Tyres

2. Contents
Tyre-functions & Properties.
Tyre-Types
 Types of carcass(Tread)
Comparison of radial & bias-ply tyres
Tyre materials & Considerations in tread
design
Tyre designation & Factors affecting tyre
life
Tyre trouble shooting & Tyre
manufacturing

3. Tyre and its functions
Tyre is a rubber member which gives
the cushion to the automobile. It
consists of outer cover i.e. tyre proper
and tube inside.
The tyre-tube assembly is mounted over
the wheel rim and air inside the tube
carries entire load and provides
cushion.

4. Tyre cross-section

5. Functions of tyre
To support the vehicle load.
To provide cushion against the
shocks.
To transmit driving and braking
forces to the road.
To provide cornering power for
smooth steering.

6. Properties of tyres
Non-skidding
Uniform wear
Load-carrying
Cushioning
 Power consumption
Tyre noise
Balancing

7. Types of tyres
Conventional tubed tyre.
Tubeless tyre.

8. Tubed tyre

9. Tubeless tyre

10. Advantages of tubeless tyres
Lesser unsprung weight.
Better cooling.
Lesser rolling resistance.
Comfortable ride.
Slower leakage of air.
Simpler assembly.
Improved safety.

11. Types of carcass(Tread)
Cross ply (or) bias ply type.
Radial ply type.
Belted bias ply type.

12. Cross ply (or) bias ply type.

13. Cross ply (or) bias ply type.

14. Radial ply type

15. Radial ply type.

16. Belted bias ply type

18. Comparison of radial and bias-ply
tyres
Advantages of radial ply tyres:-
 The side walls can be bend readily ,its shock
absorbing capacity is 25% more than bias
ply or cross ply.
 The breaker strips of radial tyres act
independently of the wall plies unlike in
cross ply where there is no breaker strip.
 Lower rolling resistance and hysteresis loss
leads to less fuel consumption.

19.  Longer tread life because of less heat build
in tyre.
 Breaking efficiency on wet roads is better
because of greater sidewall flexibility and
tread stiffness.
 Smaller slip angles and higher cornering
power which results in Better steering
characteristics.
 While taking turns it has less tendency to
distort and lift off the road from one side.
 Larger resistance to punctures ,cuts and
impacts in the tread area.

20. Tyre materials
For carcass:-
 At the time of second world war, staple cotton
was the tyre carcass material and it was
replaced with rayon.
 Then nylon was introduced which is stronger,
more elastic and cooler running than rayon.
 Then terylene was introduced.

21. For cords of stabilizer belts:-
 Rayon ,Terylene ,glass fibre or steel.
Rubber :-
 Rubber used in tyres is blend of natural and
synthetic rubbers to which various
chemicals are added to obtain desired
properties like wear resistance ,reduced
hysteresis, less internal friction.

22. Considerations in tread
design
 Grip
 Noise
 wear

23. Tyre designation

25. Factors affecting tyre life
 Inflation
 Vehicle maintenance
 Manner of driving
 Miscellaneous factors

26. Tyre trouble shooting
 Side wear of tyres
 One side wear of tyres
 Centre wear of tyre tread
 Uneven tyre wear
 Uniform rapid wear
 Rapid wear with feathered edges on the tread
 Tread cracking
 Tread or ply separation
 Loss of tyre pressure
 Radial tyre lead
 Radial tyre waddle

27. Tyre manufacturing

28. Thank you