CN-121972606-A - Forging method for improving shrinkage cavity of electroslag ingot

CN121972606ACN 121972606 ACN121972606 ACN 121972606ACN-121972606-A

Abstract

A forging method for improving shrinkage cavity of electroslag ingot comprises 1) flaw detection of an electroslag ingot to determine the depth H of the bright shrinkage cavity, dark shrinkage cavity or severe porosity of the head of the electroslag ingot, 2) heating the electroslag ingot to forging heating temperature, 3) standing the electroslag ingot with the tail facing downwards and the head facing upwards, 4) pressing and deforming the head side of the electroslag ingot within the range of 0.1-0.45D from the edge of the head, D is the diameter of the head of the electroslag ingot, the pressing height is H, one side of the head of the electroslag ingot after pressing and deforming is pressed, the center position of the head of the electroslag ingot corresponds to the bright shrinkage cavity, dark shrinkage cavity or severe porosity area of the side of the head of the electroslag ingot to be raised relative to the periphery of the head, 5) rotating the electroslag ingot by 90 ℃ along the axis of the head of the electroslag ingot to perform step 3), step 4) repeatedly operating, pressing and deforming the head of the electroslag ingot by pressing for a circle, and cutting the bright shrinkage cavity, dark shrinkage cavity or severe porosity area of the center position relative to the periphery of the head of the electroslag ingot by a circle, and 6) cutting the raised position by a rapid forging machine.

Inventors

TANG ZAIXING
ZHAO HAIPING
JIN CHENG
YU ZONGYANG
ZHANG SHAN
SUN QIANG

Assignees

宝武特种冶金有限公司

Dates

Publication Date: 20260505
Application Date: 20260303

Claims (3)

1. The forging method for improving the shrinkage cavity of the electroslag ingot is characterized by comprising the following steps of: 1) Flaw detection is carried out on the cold ingot of the electroslag ingot so as to determine the depth H of the bright shrinkage cavity, the dark shrinkage cavity or the severe loosening of the head of the electroslag ingot in mm; 2) Heating the electroslag ingot to a forging heating temperature, and preserving heat until the temperature in the electroslag ingot is uniform; 3) Standing an electroslag ingot, placing the tail of the electroslag ingot downwards, placing the head of the electroslag ingot upwards, and placing the tail of the electroslag ingot on a forging platform; 4) Carrying out local pressing deformation on one side of the head of the electroslag ingot within the range of 0.1-0.45D from the edge of the head of the electroslag ingot by utilizing a flat anvil on a rapid forging machine, wherein D is the diameter of the head of the electroslag ingot, the pressing height is H, and H is the apparent shrinkage cavity, the dark shrinkage cavity or the severely loose depth of the head of the electroslag ingot; 5) Rotating the electroslag ingot by 90 degrees along the axis of the electroslag ingot, and repeating the steps 3) and 4), wherein the other side of the head of the electroslag ingot is pressed down to enable the center position of the head of the electroslag ingot to correspond to the bright shrinkage cavity, the dark shrinkage cavity or the severe loose area of the side to be protruded relative to the periphery of the head; 6) And cutting off the raised part, namely the exposed shrinkage cavity, the hidden shrinkage cavity or the serious loose part, at the center of the head of the electroslag ingot by using a hot cutting knife of a rapid forging machine, so that the exposed shrinkage cavity, the hidden shrinkage cavity or the serious loose part on the electroslag ingot is completely removed.
2. The forging method for improving shrinkage cavity of electroslag ingot as recited in claim 1, wherein the step 4) uses a flat anvil on a rapid forging machine to simultaneously press and deform both sides of the head of the electroslag ingot within a range of 0.1-0.45 d from the edge of the head of the electroslag ingot, so that the bright shrinkage cavity, dark shrinkage cavity or severely loose area on both sides of the central position of the head of the electroslag ingot are raised relative to the periphery thereof.
3. The forging method for improving shrinkage cavity of electroslag ingot as set forth in claim 1, wherein the forging heating temperature is 1000-1300 ℃.

Description

Forging method for improving shrinkage cavity of electroslag ingot Technical Field The invention relates to the field of forging processing, in particular to a forging method for improving shrinkage cavity of an electroslag ingot. Background With the increasing requirements of aerospace, national defense and military industry, energy equipment, high-end mould manufacturing, heavy machinery, petrochemical industry and other industries on the quality of special steel materials, the electroslag steel is used as a high-quality special steel material, the application range of the electroslag steel is wider and wider, the electroslag steel is gradually developed in a large-scale direction, the ingot weight of the electroslag steel ingot is heavier, and the diameter of the electroslag ingot is larger. Along with the increasing diameter of the electroslag ingot, the electroslag ingot is often provided with obvious shrinkage cavities, dark shrinkage cavities or serious looseness at the final solidification end, namely a riser end, so that the forging quality and the material utilization rate of the electroslag ingot are seriously prevented from being improved, and huge quality loss and rapid production cost increase are caused. When the electroslag ingot is forged by a forging factory, a forging heating process, a forging deformation process, a cooling annealing process after forging and the like are formulated according to the chemical components of the electroslag ingot, the ingot size of the electroslag ingot, the external dimension, the tissue performance and other requirements of a user on materials. The electroslag ingot heating process generally adopts two to three steps to slowly heat to the forging heating temperature, then carries out heat preservation for a certain time according to the size of the steel ingot and the characteristics of the steel grade, carries out upsetting and drawing forging for a plurality of times after the heat preservation is finished, finally carries out forging production to the specification size ordered by a user, and carries out post-forging heat treatment processes such as cooling, normalizing, annealing and the like after the forging is carried out to the specification size of a finished product. It is known that in the forging upsetting-drawing process of an electroslag ingot, open shrinkage holes, dark shrinkage holes or severe looseness at a riser of the electroslag ingot are inherited to a forged product material, and the existence of the open shrinkage holes, the dark shrinkage holes or the severe looseness in the electroslag ingot causes the occurrence of defect exceeding during subsequent flaw detection or end surface inspection of the forged product material, so that defects need to be cut off, and the utilization rate of the forged material is greatly reduced due to the cutting off of the defects at the end of the forged product material. When the problems of open shrinkage cavity, dark shrinkage cavity or severe looseness of the head of the electroslag ingot are solved, engineers commonly practice to control the electroslag remelting process in the feeding process in the electroslag remelting process so as to improve the open shrinkage cavity, dark shrinkage cavity or severe looseness of the riser of the electroslag ingot. Chinese patent CN201810968696.5 discloses a "heavy electroslag remelting production process", in conventional electroslag ingot production, in order to improve quality of the final solidification end, i.e. riser end, and based on an electroslag remelting control process performed on a feeding process in an electroslag remelting process, a conventional process control manner in the electroslag remelting feeding period is to gradually reduce voltage and current from start to smelting end, reduce depth of a molten pool, and because water cooling intensity is stable and unchanged in the whole remelting period, the produced electroslag ingot riser end has light shrinkage holes, dark shrinkage holes or serious looseness, which prevents improvement of forging quality and material utilization rate of the electroslag ingot. From the aspect of patent retrieval, in order to solve the problems of clear shrinkage cavity, dark shrinkage cavity or severe porosity of the head of an electroslag ingot, the prior published patent generally carries out electroslag remelting process control on the feeding process in the electroslag remelting process, so as to solve the problems of clear shrinkage cavity, dark shrinkage cavity or severe porosity at the riser of the electroslag ingot. Disclosure of Invention The invention aims to provide a forging method for improving shrinkage cavities of electroslag ingots, which solves the problems of exceeding standard flaw detection equivalent of forged products and the like caused by bright shrinkage cavities, dark shrinkage cavities or severe looseness of the heads of the electroslag ingots in the forging process of the electros