"How is crank shaft manufactured explain"?

Answer 1

You start with a cast iron casting, a forged steel blank or a steel billet.

The casting or forged blank will be about the correct shape and will require some machining to form the bearing surfaces and the ends and remove "flash" material.

A billet crank is entirely machined from a block of metal. This is the most expensive and suitable only for top level racing.

Oil passages are drilled into the crank.

The crank is balanced by spinning the finished product. Material is removed from the counterweight portion of the crank for balancing.

Answer 2

Small crankshafts can be forged or cast with steel. They are then machined and surface hardened.
But crank shafts of very big and powerful marine engines are of the 'built-up' type. In these, the crank pin, the crank webs and the crank journal are forged separately, and then are joined together by shrink-fitting. A new development is the welded crankshafts, in which these parts are joined by welding.

Answer 3

If a crankshaft is cast, it is usually nodular cast iron not regular cast iton. I believe Henry Ford began this way of making crankshaft when he began making V-8's.

Answer 4

I do not know the answer...

but visit www.howstuffworks.com, you get all the info there