CN1710365A - Top-bottom reblowing vacuum inductive stove - Google Patents

Abstract

A top-bottom combined blowing non-vacuum induction furnace, equipped with a top-blown oxygen lance and a bottom-blown gas supply element, the top-blown oxygen lance is installed on the oxygen lance lifting system, passes through the furnace cap and the water-cooled fume hood, and the lower port is inserted into the crucible , the upper port is connected with the oxygen pipeline, the bottom blowing gas supply element is arranged at the bottom of the furnace, passes through the center of the bottom of the crucible, the upper port is connected with the inside of the crucible, and the lower port is connected with the base gas pipeline. When it is necessary to blow inert stirring gas into the crucible, set the bottom blowing vent plug, and when it needs bottom blowing oxygen, set the bottom oxygen gun. The bottom blowing oxygen lance can be fed with different proportions of oxygen and inert gas. The equipment has the function of decarburization; it can simulate various functions of the AOD furnace with a top gun, that is, the AOD-L furnace; it can be used to smelt ultra-pure steel; it can simulate the general AOD furnace to smelt stainless steel; a separate top blowing can be carried out during the smelting process Oxygen, bottom blowing oxygen, bottom blowing inert gas stirring, can also carry out top and bottom combined blowing at the same time, can be used to simulate the double blowing converter and AOD furnace to develop new processes.

Description

A non-vacuum induction furnace with combined top and bottom blowing

technical field

The invention relates to the technical field of metallurgical equipment, in particular to a non-vacuum induction furnace for iron and steel smelting.

Background technique

The currently widely used non-vacuum induction furnace does not have a top blowing system and a bottom blowing gas supply system, and it cannot blow oxygen and inert gas into the molten steel. Therefore, the type of steel made by a traditional non-vacuum induction furnace only depends on the raw material. The quality of the raw material directly affects the quality of the product, and it is difficult to adjust it in the furnace. Especially when scrap steel contains high levels of carbon, silicon, nitrogen, phosphorus, and sulfur, it is quite difficult to handle, and the steel type is difficult to become a qualified product. Even if a qualified product is smelted, the production time is relatively long and the cost of raw materials is relatively high. High, and the gas and non-metallic inclusions in the steel are high, especially the smelting of low-carbon steel and low-nitrogen steel is more difficult, or even impossible. Due to the above shortcomings of the traditional non-vacuum induction furnace, it cannot meet the needs of smelting high-purity steel.

Contents of the invention

In view of the above-mentioned problems in the prior art, the present invention provides a non-vacuum induction furnace with multiple functions and multiple functions.

The induction furnace of the present invention has the function of a general non-vacuum induction furnace. An induction coil is arranged on the outer wall of the crucible, and the induction coil is connected to an intermediate frequency power supply through a copper bar and a water-cooled cable to realize induction heating of the furnace material in the crucible. In order to make the induction furnace multi-functional and multi-purpose, and to overcome the defects of the existing non-vacuum induction furnace, a top-blown oxygen lance is installed on the upper part of the furnace, and a bottom-blown air supply element is installed at the bottom. The bottom-blown air supply element can be a bottom-blown air Plug or bottom oxygen blowing lance, in addition, set up a water-cooled fume hood, dust removal system and some necessary detection and control systems. During the smelting process, when the charge in the induction furnace is melted and reaches the blowing temperature, the water-cooled fume hood is turned to the top of the furnace mouth, and the oxygen lance is lowered to a certain height from the molten steel surface by the top-blown oxygen lance lifting mechanism to supply the molten steel Oxygen, oxygen flow is adjustable. By blowing oxygen into the molten steel, the carbon in the molten steel can be quickly reduced to a lower level. There are two types of bottom blowing gas supply components: when it is only necessary to blow inert gas into the molten steel to stir the molten steel, install the bottom blowing vent plug. Its advantage is that the bottom gas can be opened and closed arbitrarily in the presence of molten steel. No blockage; when oxygen needs to be blown from the bottom to the steel, the installed air supply element is a bottom oxygen blowing lance, which supplies oxygen to molten steel by using the bottom oxygen blowing lance, which can simulate the smelting of stainless steel or ultra-low carbon such as AOD and K-OBM steel.

Oxygen can be supplied to the furnace through the top-blown oxygen lance, so the equipment has a decarburization function, and can simulate various functions of the AOD furnace with the top lance, that is, the AOD-L furnace.

When the bottom blowing vent plug is installed, the inert stirring gas can be blown into the molten steel in the crucible, which can improve the kinetic conditions of the molten pool reaction, speed up the metallurgical rate, and make the carbon-oxygen reaction more balanced. It can smelt ultra-low carbon steel, At the same time, due to the stirring effect of the inert gas, the gas and impurity content in the steel is lower, and ultra-pure steel can be smelted.

When the bottom oxygen lance is set, the equipment has the function of bottom oxygen blowing, which can simulate the general AOD furnace to smelt stainless steel.

During the smelting process, the gas flow rate can be adjusted according to the needs, and the types of top and bottom gases can be switched arbitrarily; top blowing oxygen, bottom blowing oxygen, bottom blowing inert gas stirring can be carried out separately, and simultaneous top and bottom blowing can also be carried out. Bottom-blown oxygen is usually mixed with a certain proportion of argon or nitrogen to change the partial pressure of carbon monoxide in the gas phase after the decarburization reaction, and to meet the thermodynamic conditions of the decarburization reaction under different alloy compositions and carbon contents. The bottom blowing oxygen lance and the corresponding adjustment control system can arbitrarily set and automatically control the ratio of oxygen and inert gas, and switch the type of inert gas.

The top-bottom double blowing non-vacuum induction furnace of the present invention is equipped with a water-cooled fume hood, a water-cooled flue, and a dust collector. The gas and dust generated during the smelting process are collected and cooled by the water-cooled fume hood, and then sent to the dust collector through the water-cooled flue for dust removal. , Discharge after purification, can avoid pollution to the atmosphere.

The non-vacuum induction furnace of the present invention can decarburize, denitrogenate, remove gas and remove impurities from molten steel, shorten the smelting time, reduce the requirements for raw materials, reduce production costs, and smelt high-purity steel, especially ultra-low carbon steel, Ultra-low nitrogen steel. This equipment is not only suitable for some small and medium-sized enterprises to smelt special steel grades, but also especially suitable for major iron and steel metallurgical enterprises, technology centers and scientific research institutes to develop new varieties, and to simulate the needs of reblowing converters and AOD furnaces to develop new processes.

Description of drawings

The attached picture is a schematic diagram of the multi-functional non-vacuum induction furnace with combined top and bottom blowing, including 1 intermediate frequency power supply; 2 copper bars and water-cooled cables; 3 oxygen pipeline; 4 dust collector; 5 water-cooled flue; Oxygen gun; 8 water-cooled fume hood; 9 furnace cap; 10 molten steel; 11 crucible; 12 induction coil; 13 aluminum alloy furnace shell;

Detailed ways

As shown in the attached figure, the non-vacuum induction furnace with combined top and bottom blowing includes intermediate frequency power supply 1, copper bar and water-cooled cable 2, oxygen pipeline 3, dust collector 4, water-cooled flue 5, oxygen lance lifting system 6, and top-blown oxygen lance 7 , Water-cooled fume hood 8, furnace cap 9, crucible 11, induction coil 12, aluminum alloy furnace shell 13, bottom blowing gas supply element 14, bottom gas pipeline 15. The aluminum alloy furnace shell 13 is fixed on the cement foundation through trunnions; the inner wall of the furnace is equipped with a crucible 11, which contains the molten steel 10 to be smelted, and the outer wall of the crucible 11 is equipped with an induction coil 12, and the induction coil 12 is fixed on the aluminum alloy furnace shell through copper bolts Within 13, the induction coil 12 is connected to the intermediate frequency power supply 1 through the copper bar and the water-cooled cable 2, so as to realize the induction heating of the charge in the crucible; the furnace top is provided with a splash-proof furnace cap 9, and a water-cooled fume hood 8 is arranged above the furnace cap 9, The water-cooled fume hood 8 is connected to one end of the water-cooled flue 5, and the other end of the water-cooled flue 5 is connected to the dust collector 4. The gas and dust generated during the smelting process are collected and cooled by the water-cooled fume hood 8, and then sent to To the dust collector 4, after dust removal, discharge. The top-blown oxygen lance 7 is installed on the oxygen lance lifting system 6, the top-blown oxygen lance 7 passes through the furnace cap 9 and the water-cooled fume hood 8, the lower port is inserted into the crucible 8, and is located above the liquid level of the molten steel 10 to be smelted, and the upper port is connected to the oxygen The pipeline 3 is connected, and the top-blown oxygen lance 7 can rotate together with the water-cooled hood 8. The top-blown oxygen lance 7 is driven by the oxygen lance lifting system 6, and can be arbitrarily inserted into or lifted out of the furnace. During the smelting process, when the charge in the induction furnace is melted and reaches the blowing temperature, the water-cooled fume hood 8 is turned to the top of the furnace mouth, and the top-blown oxygen lance 7 is controlled by the oxygen lance lifting mechanism 6 to drop to a liquid level 10 meters away from the molten steel. Oxygen is supplied to the molten steel 10 at a certain height, and the oxygen flow rate is adjustable; the bottom blowing gas supply element 14 can be a bottom blowing vent plug or a bottom blowing oxygen lance, which is arranged at the bottom of the furnace, passes through the center of the bottom of the crucible 8, and the upper port and the inside of the crucible 8 Connected, the lower port is connected with the bottom gas pipeline 15, and the bottom gas pipeline 14 comes from the valve station 16.

Claims (3)

1. A top-bottom re-blowing non-vacuum induction furnace, including intermediate frequency power supply, copper bar and water-cooled cable, oxygen pipeline, dust collector, water-cooled flue, oxygen lance lifting system, top-blown oxygen lance, water-cooled hood, furnace cap, Crucible, induction coil, aluminum alloy furnace shell, bottom blowing gas supply element, bottom gas pipeline, characterized in that top blowing oxygen lance and bottom blowing gas supply element are installed, top blowing oxygen lance is installed on the oxygen lance lifting system, top blowing oxygen The gun passes through the furnace cap and the water-cooled fume hood, the lower port is inserted into the crucible, the upper port is connected to the oxygen pipeline, the bottom blowing gas supply element is installed at the bottom of the furnace, passes through the center of the bottom of the crucible, the upper port is connected to the inside of the crucible, and the lower port is connected to the base gas plumbing connection. 2. The non-vacuum induction furnace with combined top and bottom blowing according to claim 1, characterized in that the bottom blowing gas supply element is a bottom blowing vent plug or a bottom blowing oxygen lance, when it is necessary to blow inert stirring gas into the crucible, set the bottom Blow vent plug, when bottom blowing oxygen is needed, set up bottom blowing oxygen gun. 3. The application of the top-bottom combined blowing non-vacuum induction furnace as claimed in claim 1, characterized in that the bottom oxygen blowing lance of the top-bottom combined blowing non-vacuum induction furnace is used to blow oxygen into the molten steel in the crucible.

Images