Process for forging end head of electric upset steel pull rod

Abstract

The invention discloses a process for forging an end head of an electric upset steel pull rod. The process comprises the following steps of: (a) pouring a steel ingot, wherein the steel ingot comprises the following chemical components in percentage by weight, more than and equal to 0.086 and less than and equal to 0.150 percent of C, more than and equal to 1.30 and less than and equal to 1.40 percent of Si, more than and equal to 1.20 and less than and equal to 1.30 percent of Mn, more than and equal to a trace amount value and less than and equal to 0.033 percent of P, more than and equal to the trace amount value and less than and equal to 0.0260 percent of S, 0.11 to 0.22 percent of Li, more than and equal to 11.50 and less than and equal to 13.50 percent of Cr, more than and equal to the trace amount value and less than and equal to 0.0018 percent of B, and the balance of Fe and inevitable impurities; and (b) forging, namely (1) placing a to-be-upset end of the steel pull rod on an electric upsetting machine, (2) clamping a ball upsetting electrode which faces the end head of the to-be-upset end at the to-be-upset end, (3) applying current to the electrode so as to heat the to-be-upset end, and (4) applying axial upsetting force to the to-be-upset end in the axial direction of the steel pull rod so as to upset a workpiece. By the method, the end head is beneficial to large-scale industrialized production, phenomena that when the end head is forged, dirt appears, and the end head is insufficiently charged are avoided, mechanical performance of products is further improved, using materials of the products are saved, and the service life of molds of the products is prolonged.

Description

technical field [0001] The invention relates to a forging process for the end of an electric upsetting steel tie rod. Background technique [0002] The steel tie rod is an important part of the engine. Its material is made of carbon structural steel or ductile iron. There are two important parts: the main journal and the connecting rod journal. The main journal is installed on the missing body, the connecting rod neck is connected with the large end hole of the connecting rod, and the small end hole of the connecting rod is connected with the cylinder piston, which is a typical slider crank mechanism. [0003] As an important moving part, engine steel tie rods have high design requirements. At the same time, due to the extremely harsh working conditions of steel tie rods, the requirements for steel tie rod materials, steel tie rod dimensional accuracy, surface roughness, heat treatment and surface strengthening, and dynamic balance are very strict. Under the conditions of...

AI Technical Summary

Problems solved by technology

Under the condition of mass production, the traditional technology can no longer meet the current design and production needs. Under long-term and high-speed operation, the steel tie rod is very easy to fail or break prematurely, which seriously affects the life of the steel tie rod and the reliability of the whole machine.

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