Because the working mode of the piston rod is the reciprocating mode, in order to increase the life of the piston rod and reduce the wear haze of the piston rod, the blank is made of alloy structural steel of 38CrMoAlAn.

Because the piston rods are selected for small batch production, in order to improve the production power, free forging blanks should be used.

Blank shape and scale determination

(1) Blank shape

According to some machining precision requirements of the part drawing, the dimensional tolerance level of the forging is 8-12. Also, because the piston rods are selected for small batch production, consider selecting cylindrical blanks. (2) rough wood scale

Because the blank is made by free casting, according to the scale requirements of the piston rod parts drawing and the practical processing requirements, the dimensions after casting are: diameter 62mm, length 1150mm, check the technical manual, and determine the dimensions of the blank: diameter 80mm, length 760mm.