Automotive crankshafts are machine elements that transfer rotational movement into linear. The usage of crankshafts in modern automotive engines enable more engine power along with much higher efficiency rates. Automotive crankshafts are generally connected to flywheels for reducing the pulsation characteristic of the four stroke engine cycle. Along with flywheels, these are connected to the engine blocks using bearings and also to the pistons through their connecting rods.
Automotive crankshafts are an essential part of all automobile engines. Due to increased demand for lighter and more efficient engines, modern day crankshafts are becoming smaller, without compromising on performance. These are manufactured in varying designs, sizes and can be availed at affordable rates.
Construction of Automotive Crankshafts
Automotive crankshafts can be made as a single piece and can also be assembled. Although monolithic or single piece crankshafts are the most commonly used, some very small and also some larger engines do use assembled automotive crankshafts.
Typically, automotive crankshafts are manufactured from either of the two processes. These are forging and casting where the crankshafts are forged from a steel bar generally through roll forging in ductile steel. The other method is machining, where automotive crankshafts are machined out from high quality vacuum remelted steel.
Operating Conditions of Automotive Crankshafts
Crankshafts operate under enormous stress that is potentially equivalent to several tonnes of force.
During their service life, automotive crankshafts continuously experience both torsional load and also bending load.
These also withstand high operating oil temperatures and sometimes improper use of the engine (over-revving).
Due to their dynamic work nature, automotive crankshafts continuously operate under high fatigue levels.
How to Correct Automotive Crankshaft Misalignment
During alignment, if the run out at either point exceeds the service limit, then align the flywheels so that the run out falls within the service limit.
In case of horizontal misalignment, strike the projecting rim of the fly wheel with a plastic, soft lead or brass hammer.
Vertical misalignment can be corrected either by driving a wedge in between the fly wheels or just by squeezing the flywheel rims.
In case of simultaneous horizontal and vertical misalignment, always correct horizontal misalignment first.