RU1768657C - Method of electroslag remelting consumed electrode in cooled crystallizer - Google Patents

Abstract

The invention relates to metallurgy and can be used in the electrometallurgical industry in the production of high-quality steels and alloys by electroslag remelting (ESR). The aim of the invention is to improve the quality of the ingot and the durability of the molds by eliminating breakdowns. In the course of melting, the ratio of the currents flowing in the circuits is regulated: electrode 3 — ingot 5 — pallet 1 and electrode 3 — crystallizer 2 — pallet 1 by varying the resistance 4 of the circuit; electrode 3 — crystallizer 2 — pallet 1. The ratio of currents is controlled by means of variable resistance, The mold 2 included in the additional circuit — the pan 1. Between the ingot 5 and the mold 2, a potential difference is established that does not exceed the value at which a breakdown is formed. The process is conducted with a direct current of reverse polarity. The ratio of the currents in the circuits and the potential difference is established on the basis of electrical measurements. 4 C.p. f-ly, 2 ill. J (L C

Description

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The invention relates to metallurgy and can be used in the electrometallurgical industry in the production of high-quality steels and alloys by electroslag remelting.

A known method of electroslag remelting of a sacrificial electrode in a cooled mold.

Its disadvantage is the random current distribution in the slag bath, which leads to changes in the nature of the crystallization of the ingot, and also affects the course of metallurgical processes. The exclusion of the mold from the electrode-pallet systems by isolating it from the pallet leads to the formation of ingot defects, i.e. sample

The aim of the invention is to improve the quality of the ingot and the durability of the molds by eliminating breakdowns.

This is achieved by the fact that in the method of electroslag remelting of a sacrificial electrode in a cooled crystallizer during melting, the ratio of currents flowing in the electrode-ingot-pallet and electrode-crystallizer-pallet circuits is controlled by changing the electrical resistance of the electrode-crystallizer-pan circuit In this case, the current ratio is controlled by means of a variable resistance, included in the additional external circuit of the mold-tray, between the ingot and the mold set the potential difference, not exceeding boiling a value at which the sample is formed, the process is conducted at a constant current of inverse polarity, the ratio of currents in the chains and the potential difference is set based on electrical measurements.

In FIG. 1 shows a flowchart of an ESR process; in FIG. 2 is a graph of the dependence of the desulfurization of metal - on the ratio of currents -: - at el const, el

The method is as follows

A cooled mold 2 is mounted on the tray 1, into which a consumable electrode 3 is inserted. Between the electrode, the mold and the tray there is an external circuit with an adjustable variable resistance 4 connected between the mold and the tray.

In the course of melting, the ratio of the currents flowing in the circuits is regulated: electrode 3 — ingot 5 — pallet 1 and electrode 3 — crystal 0

5

lyser 2 - pallet 1, by changing the resistance 4 in the electrode-crystallizer-pallet circuit. A potential difference is established between the ingot 5 and the crystallizer 2, not exceeding the value at which a breakdown is formed. The process is conducted with a direct current of reverse polarity. The ratios of the currents in the circuits and the potential difference are established on the basis of electrical measurements. The dependence of the metal desulfurization on the ratio of the currents -p was established for melting

ke in a mold with 70 mm; eighteen

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mm; B 1150 A; 11Shp 30 V.

Changing the current distribution in the slag bath in the direction of increasing the ratio allows along with an increase

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By desulphurizing the metal to obtain a well formed ingot with directional crystallization, free from gases and nonmetallic inclusions, without defects such as breakdown, and to increase the durability of the crystallizers.

Claims (5)

1. A method of electroslag remelting of a consumable electrode in a cooled mold, characterized in that, in order to improve the quality of the ingot and the durability of the molds by eliminating breakdowns, the ratio of the currents flowing in the electrode-ingot-pallet and electrode-crystallizer - chains is regulated during melting pallet, by changing the electrical resistance of the electrode-crystallizer-pallet circuit, by changing the electrical resistance of the electrode-crystal circuit, and then p-oddon. 2. The method according to claim 1, characterized in that the current ratio is controlled by means of a variable resistance included in the additional external mold-tray circuit. 3. The method according to paragraphs. 1 and 2, which implies that between the slig and the mold, a potential difference is set that does not exceed the value at which a breakdown is formed, 4. The method according to paragraphs. -3, characterized in that the process is conducted with a constant current of reverse polarity. 5. The method according to paragraphs. 1-4, characterized in that the ratio of currents in the circuits and the potential difference is established on the basis of electrical measurements, 5 /% sj about jf% sj% sjc / 7 0,040 0,030 % &  with 0,020 0, Of O 20 40 60 Fie. 2 % 3 9 / g -4% $ 1 60 / b 1 / d7;% I y / g