The Clutch lining or friction materials of the clutch are the adhesive components attached to the clutch plates for frictional engagement of the clutch so that the power transmits from engine to the gearbox.
Types of Clutch Friction material
The friction linings of the clutch plate are generally of 3 types:
- Mill-board type.
- Moulded type.
- Woven type.
Mill-board type friction materials mainly include asbestos sheets treated with different types of impregnants. They are cheap as well as quite satisfactory in operation.
Moulded type friction materials are made from a matrix of asbestos fibre and starch or any other suitable binding materials. They are then heated to a certain temperature for moulding in the dies under pressure. They are also made into sheets which are rolled, pressed and baked till they are extremely hard and dense. Metallic wires are also inserted sometimes to improve wearing qualities. In comparison to the other types, they can take heavier working loads. The only disadvantage of this type of friction materials is that each clutch facing has to be moulded separately.
Woven type friction materials are made by impregnating a cloth with a certain type of binders or by wearing of threads of copper or brass wires covered with long fibre asbestos and cotton. The woven sheets treated with a binding solution is baked and rolled.
The woven type friction materials are further classified into two types: laminated type and solid woven type. The laminated type of friction material is prepared by holding one layer over the other with a binder between them. In the solid woven type, the cloth is woven just to the required thickness.
For more information about different types of friction materials watch the video below :
The most common friction materials are as follows:
- Leather. Co-efficient of friction 0.27.
- Cork. efficient of friction 0.32.
- Fabric. Co-efficient of friction 0.40.
- Asbestos. Co-efficient of friction 0.20.
- Raybestos and Ferodo. Co-efficient of friction 0.20.
They are almost universally used for clutch lining.
PROPERTIES OF GOOD CLUTCH LINING
- Good wearing properties.
- High coefficient of friction.
- High resistance to heat.
- The good binder in it.
- Cheap and easy to manufacture.