Crank Shaft

The main function of the crankshaft in an excavator is to convert the thrust transmitted by the connecting rod into rotational torque, thereby transforming the linear reciprocating motion of the piston into the circular rotational motion of the crankshaft. In addition, the crankshaft also transfers the engine’s torque to the transmission system through the flywheel, and drives the engine’s valve mechanism and other auxiliary equipment. The crankshaft is a critical component of the engine, responsible for converting the force from the connecting rod into torque output to drive other accessories on the engine. Due to the combined action of centrifugal force from rotating mass, the cyclical inertia forces of gas, and the reciprocating inertia forces, the crankshaft needs to withstand bending and twisting loads. Therefore, it requires sufficient strength and stiffness, and the surface of the journal needs to be wear-resistant, work uniformly, and have good balance.