Camshaft materials and technology

The oval shape of the cam lobe determines the lift ( Displacement ) of inlet and exhaust valves. The
valve itself has an inertial mass. If the curved shape of the cam lobe surface is not designed appropriately, then the valve cannot accurately follow the contour and this will result in irregular motion.

The camshaft material should combine a strong
shaft with hard cam lobes.The most widely used
material for camshafts at present is chilled cast
iron Chilled Cast iron ,hardenable cast iron or
JIS-SCM420 forging followed by carburizing for
Improving Wear resistance of the cam lobe .

Lighter moving parts in The valve train will enable
high-speed revolutions.Increasing the tension of
The valve spring will increase reactive force, help
to prevent irregular motion of the valves.However
,the high reactive force will result in high contact
pressure on the cam lobe ,so the cam lobe should
have high wear resistance.

It is essential to supply adequate amounts of
Lubricating oil to the cam lobe.

The contact between the curved surface of the cam lobe and the flat face of the valve lifter ( bucket tappet ) generates high stress,and therefore both parts require high wear resistance where contact occurs.