 Converted into the rotating motion of the crankshaft to be connected to the linear energy of reciprocating piston engine parts

 Endure compressive strength, tensile, and bending  Need strength, stiffness and reducing weight  Used chrome-molybden steel, through the description of the above

 Raw material  Impression-die forging  Annealing  Rolling(Flat, Structural shape)  Machining  Heat treatment  Grinding

 Steel(Carbon 0.25~0.35%)  Chrome : 0.8~1.1%  Molybden : 0.15~0.25%  Manganese : 0.4~0.6%

 Flat rolling  Structural shape rolling

 Machining & Grinding Reduce surface roughness Increase accuracy  Heat treatment(Tempering) Quenching is increase strength but occur brittleness Tempering over 200˚C reduce brittleness