9/20/2008 - Importatnt facors for steering ystem

Thee are  important alignment factors are as under:-

Ø  Caster.

Ø  Camber.

Ø  Toe-in

Ø  King pin inclination

Ø  Toe out or steering geometry

Ø  Tracking.

ü  Caster: it is backward tilt of the king pin and axle at the top. The purpose of caster is to give the vehicle directional stability or ability to travel straight ahead with a minimum of actual steering by the driver. This is accomplished by the fact that the projected centre line of king pin strikes the road ahead of the contact point of the tyre. This has a tendency to lead or drag the wheel behind it giving the vehicle directional stability. 

ü  Chamber: it is outward tilt of the wheels at the top. It is to allow the load to bear more directly down through the king pin there by relieving any binding action of pivots in their bearings.

ü  Toe-in: the adjustment for gathering the wheels inward at the front is known as toe-in. it means that the distance between the front wheels at the front is less than the distance at the back.

ü  King-pin inclination: it is inward tilt of king-pin at the top. It tends to keep the stub axle pointed outward in line with the axle just as caster tends to keep the wheels pointed ahead.

ü  Toe-out or steering geometry: the difference in angles between the front wheels and the chassis frame during turns is known as toe-out or steering geometry. It is toed out position the front wheels assume when making  a turn.

ü  Tracking: rear wheels should follow I the tracks of front wheels in a parallel position. Tyre scuffing and hard steering are caused by improper tracking which is due to bent chassis frame.

9/20/2008 - Factors affecting steering

There are six types of factors affecting in steering are as follows:

1.      Steering gear ratio and back lash.

2.      Steering linkage connection.

3.      Type pressure.

4.      Condition of king pins and bushings.

5.      Wheel alignment.

Ø  Steering gear ratio: the steering gear provides mechanical advantage for the driver to guide the vehicle by exerting only a small amount of physical effort at the steering wheel. Steering gears usually have a mechanical advantage of 12 to 1and higher.

Ø  Steering linkage connections: They must provide free movement of the linkage to transmit driver’s effort at the steering wheel to the knuckles. If there is more play in the joints, most of the efforts shall be going waste and if there is less play, hard steering would result in.

Ø  Type pressure: It should be as per specifications. less or uneven pressure of air in the wheels shall result in hard steering and more tyre pressure shall lead to wobbling.

Ø  Play in wheel bearings: The wheel bearing should be properly adjusted. Less play shall result in hard steering and more play shall effect wheel alignment and lead to wheel wander.

Ø  Condition of king pins and bearings: The front portion vehicle load acts through the pins. If the pins. If the pins are tight in the bushes, hard steering shall result in and if there is more play, wheel alignment shall be affected, which has great influence on the steering operation.