Forging method for six throw crankshaft

Abstract

The invention discloses a forging method for a six throw crankshaft, comprising the step of pouring cylindrical blank. The cylindrical blank comprises the following chemical compositions in percentage by weight: 0.12-0.40 percent of C, 0.42-2.0 percent of Mn, 0.7-1.5 percent of Si, 0.09-0.15 percent of V, 0.11-0.22 percent of Ti, 0.4-1.4 percent of Cr, 0.4-1.5 percent of Ni, 0.15-0.30 percent of Mo, 0.4-0.8 percent of Li, 0.04-0.08 percent of Nb, 0.15-0.20 percent of Al, 0.15-0.50 percent of Mg, wherein the weight percentage of P is less than or equal to 0.030 percent, the weight percentage of S is less than or equal to 0.030 percent, and Fe accounts for the rest amount. According to the forging method for the six throw crankshaft, the defects in the prior art are overcome, energy sources are saved, the quality of heat treatment is improved, the production cycle is shortened, the production cost is reduced, and the radiation pollution to the workshop environment is reduced.

Description

technical field [0001] The invention relates to the processing field of positioning hooks, in particular to a forging method of a six-turn crankshaft. Background technique [0002] The six-throw crankshaft includes several sections, the crankshafts are 120°, and the included angles are evenly distributed. Large multi-turn crankshafts are mainly used in large engines. Its main function is to convert the force transmitted from the connecting rod into torque. It is the core part of the engine and is widely used in engines in large machinery, chemical industry, locomotives, ships and other industries. Its forging methods include fully assembled, semi-assembled and integral forging methods. Due to the integration of the crankshaft and the curved diameter and the continuous forging fibers, the overall forging is difficult and the quality of the forgings is high, so the forging is difficult, the shape is complex during the forging process, and quality problems are easy to occur (...

AI Technical Summary

Problems solved by technology

Due to the integration of the crankshaft and the curved diameter and the continuous forging fibers, the overall forging is difficult and the quality of the forgings is high, so the forging is difficult, the shape is complex during the forging process, and quality problems are easy to occur (such as folding 120 ° included angle offset, etc.)

At present, when the overall forging of multi-turn crankshafts is carried out in China, misalignment and angle presets are adopted. Most of the crankshafts are forged from a circle to a hexagon or from an octagon to a hexagon. The forging process requires many fires, the deformation process is complicated, and the pass rate is low.