The camshaft is a component of the piston engine. Its role is to control the opening and closing of the valve. Although the speed of the camshaft is half of the crankshaft in a four-stroke engine (the speed of the camshaft is the same as that of the crankshaft in a two-stroke engine), usually its speed is still high and it needs to withstand a lot of torque, so the design is correct. Camshafts are highly demanding in terms of strength and support, and are generally made of high quality alloy steel or alloy steel. Since the law of valve motion is related to the power and running characteristics of an engine, the camshaft design plays an important role in the design process of the engine.