Novel method for producing high-grade alloy steel seamless steel tube

Abstract

The invention relates to a novel method for producing a high-grade alloy steel seamless steel tube, which comprises the following steps: A. manufacturing an alloy steel hollow pipe blank; B. inserting a common carbon steel core material into the hollow pipe blank so that the hollow pipe blank is changed into a compound blank with the carbon steel core material; C. carrying out pressure processing on the compound blank till the size conforms to the set requirement; D. pulling out the compound blank after pressure processing, integrally pulling out the common carbon steel core material in the compound blank after the pressure processing and processing the compound blank into a pipe conforming to the requirement; and E. carrying out heat treatment, heat and tail cutting and finishing on the pipe to manufacture the finished pipe. Because the common carbon steel core material is added into a pierced pipe, the method provides a new opportunity for carrying out more reasonable and concise forging-rolling deformation by a centrifugal casting blank and other hollow blanks, can greatly save valuable alloy metal, improve the yield of finished products, reduce the material cost and improve the product quality; the processing process flow is shortened, and the tonnage requirement of equipment is shortened, thereby saving energy, reducing consumption and processing and operating cost and improving the production efficiency; the pressure processing of the pipe is converted into the pressure processing of a bar, thereby reducing the technical difficulty of process and quality control.

Description

technical field [0001] The invention relates to the manufacturing technology of seamless steel pipes, in particular to the manufacturing technology of high-end seamless pipes made of high-grade alloy steel with medium and large diameters, medium and thick walls, and difficult to process. Background technique [0002] Steel has good comprehensive performance, can bear the required load and have the required service life cycle under different working conditions, and has good process performance. It is an indispensable and important basic material for national economic construction. Generally speaking, carbon-iron alloys with a carbon content of 0.02%-2% are called steel, and carbon-iron alloys with a carbon content greater than 2% are called cast iron. According to different classification standards, steel can be divided into different categories. According to the chemical composition of steel, it can be divided into carbon steel and alloy steel: [0003] In addition to iron...

AI Technical Summary

Problems solved by technology

Once a defect occurs, not only cannot be eradicated in the subsequent processing process, but will continue to expand, which may have a serious adverse effect on the quality and yield of the finished product;

This method, because alloy steel is difficult to machine, not only requires high machining equipment, but also has extremely low production efficiency, and seriously wastes precious alloy steel metal;

[0009] In addition, the pressure processing of pipe fittings with a mandrel is limited by factors such as processing equipment, tooling and mold manufacturing and transportation, and deformation temperature control. There are many processing passes, complex auxiliary processes, and difficult quality control, resulting in medium and large diameters. The difficulty of high-end pipe processing has increased sharply

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