Based on how they are manufactured, crankshafts can be classified into three types: cast, forged or billet. In the automotive industry, casting and forging are more prominently used.
A crankshaft is a mechanical part of a car's engine that functions by transforming the straight line movement of the pistons into a circular motion to drive the vehicle forward. This device is commonly designed with bearing journals, counterweights, a throw, a crankgear, a power-take-off and a crankpin journal.
The process involved in constructing crankshafts often determines their durability and performance level. A standard technique called casting entails pouring molten iron or steel into a crankshaft mold. Manufacturers generally favor the use of cast crankshafts in their vehicles due to the economical advantage in producing this type of crankshaft.
The forging method requires the application of extreme temperatures to liquefy a cylindrical piece of metal. Subsequent processing involves compacting the material into a hardened state through the use of pressure devices. While forged crankshafts are more heavy-duty compared to their cast counterparts, the forging machinery is more expensive than the tools used in casting.
Billet crankshafts use the same materials and undergo a similar process as forged crankshafts. The main distinction between the two types is the level of compaction. Billet crankshafts are less densely packed compared to forged crankshafts and they are the costliest among the three types of crankshafts.