CN113913580B - Production method of ultralow-carbon low-aluminum structural molten steel - Google Patents
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
- C21C5/30—Regulating or controlling the blowing
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/06—Deoxidising, e.g. killing
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/068—Decarburising
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/072—Treatment with gases
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/076—Use of slags or fluxes as treating agents
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Abstract
The invention discloses a production method of ultra-low carbon low aluminum structure molten steel, which mainly solves the technical problems of low control precision of chemical components and high production cost in the production process of the existing ultra-low carbon low aluminum structure molten steel. The technical scheme is that the production method of the ultra-low carbon low aluminum structure molten steel comprises the following steps: 1) Desulfurizing molten iron; 2) Smelting by adopting a top-bottom combined blown converter; controlling the smelting end point of the converter, and detecting the W [ C ] and the temperature in the molten steel at the blowing end point of the converter; immediately tapping after the converter blowing is finished; 3) Conveying the molten steel in the ladle to an argon blowing station for regulating and controlling the temperature of the molten steel; 4) And (3) transporting the molten steel in the ladle to an RH furnace for refining treatment, and carrying out vacuum decarburization, deoxidation alloying and circulation nitrogen increase on the molten steel. The invention realizes the precise control of the chemical components of the ultralow-carbon low-aluminum structural steel and reduces the production cost.
Description
Technical Field
The invention relates to a production method of structural steel, in particular to a production method of ultralow-carbon and low-aluminum structural molten steel, belonging to the technical field of steel smelting and continuous casting.
Background
The ultra-low carbon low aluminum structural steel is mainly used for radiating fins made of steel-aluminum composite plates, main chambers of automobile engine radiator boxes, composite inner containers of electric cookers and the like, the product is required to have the characteristics of good heat conductivity, corrosion resistance, light weight and the like, the required oxygen content and carbon content of the steel are accurately controlled, and nitrogen increasing process treatment needs to be carried out on molten steel.
The weight percentage of the chemical components of the ultra-low carbon low aluminum structural steel is as follows: c: 0.0025-0.0080%, si is less than or equal to 0.01%, mn: 0.20-0.32%, P is less than or equal to 0.015%, S is less than or equal to 0.004%, alt is less than or equal to 0.005%, N:0.0035 to 0.0070%, O: 0.0100-0.0120% and the balance of Fe and inevitable impurities.
In the existing production process, after high vacuum decarburization of molten steel is finished, deoxidation alloy is added into the molten steel, alloying operation is carried out after the deoxidation reaches a target value, and finally nitrogen increase control is carried out by circulating current nitrogen increase or adding nitrogen-containing alloy.
The main defects of the smelting process are as follows: in a vacuum state, carbon-oxygen reaction is always carried out when the molten steel is rich in oxygen, the carbon-oxygen balance is in an unstable state, and the components of the molten steel are difficult to control; because the circulation nitrogen increase is in an oxygen-enriched vacuum state, part of blown nitrogen is discharged as waste gas, a small amount of nitrogen enters molten steel, and the fluctuation of nitrogen increase is large and unstable; the nitrogenous alloy is easy to escape in aging, has strict requirements on storage, is difficult to control under the condition of large-scale production, is unstable in nitrogen increase of molten steel, and has high cost and long detection period.
Chinese patent application with application publication No. CN108998613A discloses a method for controlling free oxygen in ultra-low carbon and low aluminum steel, which comprises performing vacuum cycle decarburization and deoxidation in an RH vacuum refining furnace, testing the oxygen content in molten steel after 5-10 min of decarburization, adding a first batch of deoxidizer when the oxygen content is more than 0.04% by weight, and adding a second batch of deoxidizer for deoxidation when the carbon content is less than or equal to 0.003% by weight and the oxygen content is less than or equal to 0.04% by weight; when the chemical component content in the molten steel and the temperature of the molten steel reach target values, the treatment process is finished; and after standing for 15-25 min, transferring the molten steel to a continuous casting process. The technical scheme disclosed by the patent has the following problems: 1. the method can effectively control the oxygen content of the molten steel at the right time, but does not control the vacuum degree, and the carbon-oxygen reaction can be continuously carried out in a high vacuum state, so that the carbon and oxygen control is continuously reduced. 2. The method controls the carbon content of the molten steel through the carbon-oxygen balance of the RH furnace vacuum decarburization, has the requirement of accurately controlling the steel grade with the upper and lower limits of the carbon content, and has inaccurate carbon alloying process of the molten steel due to the difference between the oxygen determination presumption and the actual components.
The Chinese patent application with the application publication number of CN 108396091A discloses a smelting method of low-silicon low-aluminum low-oxygen steel, which discloses that lime and passivated metal magnesium powder are sprayed into molten iron according to the condition of the molten iron in the molten iron pretreatment, and molten iron S is removed to be less than 0.0020 percent; thoroughly slagging off after desulfurization, wherein the temperature of molten iron after slagging off is more than 1260 ℃, the steel ladle after tapping is conveyed to an RH station, and the steel ladle enters a vacuum mode after entering the station and measuring the temperature, so that the time of RH vacuum degree below 0.2kPa is not less than 20min to ensure the carbon deoxidation capability and effect; then, determining oxygen and adding aluminum, controlling the oxygen activity to be 40-60 ppm, then breaking the gap, then feeding Ca Fe wire, and stopping wire feeding when the Ca content in the steel reaches 10-25 ppm; and after the wire feeding is finished, performing weak argon blowing operation, wherein the weak argon blowing time is more than 10min, and then directly pouring on a machine. The technical scheme disclosed by the patent has the following problems: 1. the molten iron pretreatment does not define slag skimming methods and standards, large deviation can be caused in actual execution, cost waste is caused by more slag skimming, and the amount of resulfurization is reduced by slag skimming, so that the components are removed. 2. The smelting method only aims at low-carbon steel, and lacks a stable nitrogen increasing control method of the ultra-low-carbon steel in an oxygen-enriched state. 3. When the oxygen activity is controlled to be 40-60 ppm, ca Fe wire feeding is carried out to cause large splashing, the effects of changing the shape of inclusions and improving the continuous casting castability by calcium treatment cannot be achieved, and most of the calcium treatment is used for deoxidation.
Disclosure of Invention
The invention aims to provide a production method of ultra-low carbon low aluminum structure molten steel, which mainly solves the technical problems of low control precision of chemical components and high production cost in the production process of the existing ultra-low carbon low aluminum structure molten steel; the method of the invention thoroughly solves the problems of fluctuation of carbon content of oxygen-containing molten steel, inaccurate control of free oxygen after aluminum addition and deoxidation, unstable yield of nitrogen increase by circulating nitrogen and high production cost of molten steel in the vacuum treatment process of the RH furnace.
The technical scheme of the invention is that the production method of the ultra-low carbon and low aluminum structure molten steel comprises the following steps:
1) The molten iron desulphurization comprises slagging-off before desulphurization, desulphurization and slagging-off after desulphurization of the molten iron in the ladle, after slagging-off after desulphurization is finished, the proportion of the exposed liquid level of the molten iron in the ladle to the liquid level of the whole molten iron is controlled to be more than or equal to 75 percent, before desulphurization, the WS in the chemical components of the molten iron is 0.010-0.10 percent, the Si is 0.15-0.60 percent, and the temperature of the molten iron is 1320-1450 ℃; after desulfurization, w [ S ] in molten iron is 0.0010-0.0015%;
2) A top-bottom combined blowing converter is used for smelting molten steel, and the weight percentage of the raw materials for charging metal main materials is that the molten iron is 92-100%, the rest is light scrap steel, and the chemical composition of the molten iron is w [ S ]]Less than or equal to 0.0020 percent, w [ S ] in chemical components of light scrap steel]≤0.0060％；In the molten steel at the converting end point of the converter [ C ]]: 0.026-0.054%, the temperature of molten steel when tapping from converter is 1655-1670 deg.C, adding 3.0-5.0 kg quicklime into molten steel in steel ladle per ton steel during tapping from converter; after the tapping of the converter is finished, adding a low-carbon low-silicon composite deoxidizer into the molten steel in the ladle to modify the ladle slag, controlling TFe in the ladle slag to be less than or equal to 3.0 and controlling w (CaO)/w (Al) in the ladle slag 2 O 3 ) The value of the deoxidizer is 1.0 to 1.5, the adding amount of the low-carbon low-silicon compound deoxidizer is 2.0 to 3.0 kg/ton steel, and the chemical components of the low-carbon low-silicon compound deoxidizer in percentage by weight are 26 to 30 percent of Al and 26 to 30 percent of Al 2 O 3 40％～50％、CaO 15％～25％、SiO 2 Less than or equal to 10 percent and H 2 O≤1％；
3) Transporting molten steel in a ladle to an argon blowing station for molten steel temperature regulation, introducing argon into the molten steel in the ladle to stir the molten steel for 3.0-3.5 min after the molten steel in the ladle is transported into the argon blowing station, and controlling the flow of the argon to be 20-30L/h; then detecting the free oxygen content in the molten steel of the ladle and the temperature of the molten steel; after the temperature measurement and the oxygen determination of the molten steel are finished, adding scrap steel into the molten steel, and regulating the temperature of the molten steel to be 1610-1620 ℃;
4) The molten steel in the ladle is transported to an RH furnace for refining treatment, and the molten steel is subjected to vacuum decarburization, deoxidation alloying and circulation flow nitrogen increase; breaking vacuum in the RH furnace after the circulation nitrogen increasing is finished, transporting the molten steel out of the RH furnace after the current furnace molten steel treatment is finished, wherein the molten steel after the RH furnace refining treatment comprises the following chemical components in percentage by weight: c: 0.0025-0.0080%, si is less than or equal to 0.01%, mn: 0.20-0.32%, P is less than or equal to 0.015%, S is less than or equal to 0.004%, alt is less than or equal to 0.005%, N:0.0035 to 0.0070%, O: 0.0100-0.0120% and the balance of Fe and inevitable impurities;
the molten steel is subjected to vacuum decarburization, the molten steel is subjected to forced decarburization by blowing oxygen by a top lance in the early stage of the vacuum decarburization of the molten steel, the vacuum degree in a vacuum tank of an RH furnace is controlled to be 5-15 KPa in the forced decarburization process of the molten steel, the flow rate of circulating gas is 1400-1600L/min, the pressure of the circulating gas is 0.65-0.85 MPa, and the w [ O ] in the molten steel is controlled to be 450-550 ppm after the forced decarburization;
after the top lance oxygen blowing forced decarbonization is finished, the molten steel is subjected to natural decarbonization for 13-17 min, the vacuum degree in a vacuum tank of an RH furnace is controlled to be less than or equal to 0.27KPa in the process of the natural decarbonization of the molten steel, the flow rate of circulating gas is 1600-1800L/min, the pressure of the circulating gas is 0.75-0.95 MPa, and the w [ O ] in the molten steel is controlled to be 300-400 ppm after the natural decarbonization;
deoxidizing and alloying the molten steel, deoxidizing the molten steel after decarburization of the molten steel, controlling the vacuum degree of the molten steel to be 5-15 KPa, adding aluminum blocks into the molten steel in 2 batches for deoxidation, wherein the batch interval is 1-2 min, and controlling the content of W [ O ] in the molten steel to be 120-160 ppm after the aluminum blocks are added for deoxidation for the first time; after the second addition of aluminium block to make deoxidation it can control w [ O ] in the molten steel to be less than 120ppm; after the molten steel is deoxidized, the alloy components of the molten steel are regulated, and high-carbon ferromanganese is added into the molten steel for carbon blending and manganese metal regulation; controlling the vacuum degree in a vacuum tank of the RH furnace to be 5-15 KPa, the circulation gas flow to be 1600-1800L/min and the circulation gas pressure to be 0.75-0.95 MPa in the molten steel deoxidation alloying process;
the molten steel is subjected to circulation nitrogen increase, the molten steel is subjected to circulation nitrogen increase after the regulation and control of alloy components of the molten steel are finished, the vacuum degree in a vacuum tank of the RH furnace is controlled to be 5-15 KPa in the circulation nitrogen increase process of the molten steel, the circulation gas is nitrogen, the flow rate of the circulation gas is 1600-2000L/min, the pressure of the circulation gas is 0.75-0.95 MPa, and the circulation is carried out for 13-17 min.
Further, in the step 4), the RH furnace performs vacuum decarburization and deoxidation alloying on the molten steel, and the adopted circulating gas is argon.
Further, the method of the invention comprises the following steps: before the RH furnace processes the next molten steel, the RH furnace vacuum tank is subjected to heat preservation baking by using a top gun, coke oven gas is adopted for heat preservation baking, and the flow of the coke oven gas is 250-300 m 3 And h, introducing nitrogen into the RH furnace circulating pipe in the baking process, wherein the nitrogen circulates in the RH furnace circulating pipe, and the circulation flow of the nitrogen is 500-800L/min.
The RH furnace vacuum groove is subjected to heat preservation baking, so that the pressure in the RH furnace vacuum groove is ensured to be greater than the atmospheric pressure, air is prevented from entering the RH furnace vacuum groove, nitrogen and oxygen absorption in cold steel is reduced, the control of the nitrogen and oxygen content of molten steel in the next furnace is facilitated, and the RH furnace treatment effect is ensured.
Compared with the prior art, the invention has the following positive effects: 1. the method realizes the accurate control of the chemical components of the molten steel, and the trace recarburization control is carried out by adding the carbon-containing deoxidation alloy into the molten steel, so that the phenomenon of unstable recarburization components caused by vacuum decarburization or adding a recarburizing agent is solved, the steel smelting rate is improved, the manganese alloying cost is reduced, and the production cost is reduced. 2. In the invention, deoxidation alloy is added in two times in an RH vacuum tank to accurately control the residual oxygen content and ensure that the w [ Alt ] of the molten steel is less than or equal to 0.005 percent. When the deoxidation alloy is added, the vacuum degree in the vacuum tank is controlled during deoxidation, the carbon-oxygen reaction in the process is reduced, and the carbon-oxygen balance of the molten steel can be effectively maintained. 3. The present invention avoids the unstable phenomenon of circulating nitrogen increase in high vacuum state by controlling vacuum degree, circulating nitrogen pressure and flow rate under the oxygen-enriched state with molten steel W O of 120-160 ppm; by stabilizing the pressure and flow of the circulating nitrogen in the nitrogen increasing process, the phenomenon of unbalanced nitrogen increase instability of pressure and flow caused by the blockage of a circulating argon pipeline is solved.
Detailed Description
The present invention is further illustrated below with reference to examples 1 to 4, which are shown in tables 1 to 4.
In the embodiment of the invention, 150 tons of top-bottom combined blown ultra-low carbon low aluminum structural steel is adopted, and the metallurgical steel species in the embodiments 1 to 4 are cold forming steel with the brand number of TN0230E1; the production method comprises the following steps: molten iron desulphurization pretreatment, converter smelting, molten steel treatment in an argon blowing station, and RH furnace vacuum refining. The control parameters of the molten steel production of the embodiment of the invention are shown in tables 1 to 4.
TABLE 1 parameters of the converter for smelting metal materials in the examples of the present invention
TABLE 2 chemical composition and temperature of molten steel at the smelting end point of the converter according to the embodiment of the present invention
TABLE 3 consumption parameters of alloy and auxiliary materials in the tapping process of the converter according to the example of the invention
| Heat of furnace | Quicklime/kg/ton steel | Low-carbon low-silicon composite deoxidizer/kg/ton steel |
| Example 1 | 3.50 | 2.52 |
| Example 2 | 3.52 | 2.55 |
| Example 3 | 3.49 | 2.49 |
| Example 4 | 3.53 | 2.51 |
TABLE 4 chemical composition and temperature of molten steel discharged from RH furnace according to the embodiment of the present invention
In addition to the above embodiments, the present invention may have other embodiments. All technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the claims of the present invention.
Claims (3)
1. A production method of ultra-low carbon low aluminum structure molten steel is characterized by comprising the following steps:
1) The molten iron desulphurization comprises slagging-off before desulphurization, desulphurization and slagging-off after desulphurization of the molten iron in the ladle, after slagging-off after desulphurization is finished, the proportion of the exposed liquid level of the molten iron in the ladle to the liquid level of the whole molten iron is controlled to be more than or equal to 75 percent, before desulphurization, the molten iron chemical components comprise 0.010-0.10 percent of WS, 0.15-0.60 percent of WSi, and the temperature of the molten iron is 1320-1450 ℃; after desulfurization, w [ S ] in the molten iron is 0.0010-0.0015%;
2) A top-bottom combined blowing converter is used for smelting molten steel, and the weight percentage of the raw materials for charging metal main materials is that the molten iron is 92-100%, the rest is light scrap steel, and the chemical composition of the molten iron is w [ S ]]Less than or equal to 0.0020 percent, w [ S ] in chemical components of light scrap steel]Less than or equal to 0.0060 percent; w [ C ] in molten steel at converter blowing end point]: 0.026-0.054%, the temperature of molten steel when tapping from converter is 1655-1670 deg.C, adding 3.0-5.0 kg quicklime per ton steel into molten steel in steel ladle during tapping from converter; after the tapping of the converter is finished, adding a low-carbon low-silicon composite deoxidizer into the molten steel in the ladle to modify the ladle slag, controlling TFe in the ladle slag to be less than or equal to 3.0 and controlling w (CaO)/w (Al) in the ladle slag 2 O 3 ) The value of the deoxidizer is 1.0 to 1.5, the adding amount of the low-carbon low-silicon compound deoxidizer is 2.0 to 3.0 kg/ton steel, and the chemical components of the low-carbon low-silicon compound deoxidizer in percentage by weight are 26 to 30 percent of Al and 26 to 30 percent of Al 2 O 3 40％～50％、CaO 15％～25％、SiO 2 Less than or equal to 10 percent and H 2 O≤1％；
3) Transporting molten steel in a ladle to an argon blowing station for regulating and controlling the temperature of the molten steel, introducing argon into the molten steel in the ladle to stir the molten steel for 3.0-3.5 min after the molten steel in the ladle is transported into the argon blowing station, and controlling the flow of the argon to be 20-30L/h; then detecting the free oxygen content in the molten steel of the ladle and the temperature of the molten steel; after the temperature measurement and the oxygen determination of the molten steel are finished, adding scrap steel into the molten steel, and regulating the temperature of the molten steel to be 1610-1620 ℃;
4) Molten steel in the ladle is transported to an RH furnace for refining treatment, and the molten steel is subjected to vacuum decarburization, deoxidation alloying and circulation nitrogen increasing; breaking vacuum in the RH furnace after the circulation nitrogen increasing is finished, transporting the molten steel out of the RH furnace after the current furnace molten steel treatment is finished, wherein the molten steel after the RH furnace refining treatment comprises the following chemical components in percentage by weight: c: 0.0025-0.0080%, si is less than or equal to 0.01%, mn: 0.20-0.32%, P is less than or equal to 0.015%, S is less than or equal to 0.004%, alt is less than or equal to 0.005%, N:0.0035 to 0.0070%, O: 0.0100-0.0120% and the balance of Fe and inevitable impurities;
the molten steel is subjected to vacuum decarburization, the molten steel is subjected to forced decarburization by blowing oxygen by a top lance in the early stage of the vacuum decarburization of the molten steel, the vacuum degree in a vacuum tank of an RH furnace is controlled to be 5-15 KPa in the forced decarburization process of the molten steel, the flow rate of circulating gas is 1400-1600L/min, the pressure of the circulating gas is 0.65-0.85 MPa, and the w [ O ] in the molten steel is controlled to be 450-550 ppm after the forced decarburization;
after the top lance oxygen blowing forced decarburization is finished, the molten steel is subjected to natural decarburization for 13-17 min, the vacuum degree in a vacuum tank of an RH furnace is controlled to be less than or equal to 0.27KPa in the natural decarburization process of the molten steel, the flow rate of circulating gas is 1600-1800L/min, the pressure of the circulating gas is 0.75-0.95 MPa, and the w [ O ] in the molten steel is controlled to be 300-400 ppm after the natural decarburization;
deoxidizing and alloying the molten steel, deoxidizing the molten steel after decarburization of the molten steel, controlling the vacuum degree of the molten steel to be 5-15 KPa, adding aluminum blocks into the molten steel in 2 batches for deoxidation, wherein the batch interval is 1-2 min, and controlling the content of W [ O ] in the molten steel to be 120-160 ppm after the aluminum blocks are added for deoxidation for the first time; after the second addition of aluminium block to make deoxidation it can control w [ O ] in the molten steel to be less than 120ppm; after the molten steel is deoxidized, the alloy components of the molten steel are regulated, and high-carbon ferromanganese is added into the molten steel for carbon blending and manganese metal regulation; controlling the vacuum degree in a vacuum tank of the RH furnace to be 5-15 KPa, the circulation gas flow to be 1600-1800L/min and the circulation gas pressure to be 0.75-0.95 MPa in the molten steel deoxidation alloying process;
and performing circulation nitrogen increase on the molten steel, performing circulation nitrogen increase on the molten steel after the regulation and control of alloy components of the molten steel are finished, controlling the vacuum degree in a vacuum tank of the RH furnace to be 5-15 KPa in the circulation nitrogen increase process of the molten steel, wherein the circulation gas is nitrogen, the flow rate of the circulation gas is 1600-2000L/min, the pressure of the circulation gas is 0.75-0.95 MPa, and the circulation is circulated for 13-17 min.
2. The method for manufacturing ultra-low carbon and low aluminum structural molten steel as set forth in claim 1, wherein the RH furnace of step 4) performs vacuum decarburization and deoxidation alloying on the molten steel, and argon is used as a circulating gas.
3. The method for producing ultra-low carbon and low aluminum structural molten steel of claim 1, wherein a top gun is used to perform heat preservation baking on a vacuum tank of the RH furnace before the RH furnace processes the next molten steel, the heat preservation baking is performed by using coke oven gas, the flow rate of the coke oven gas is 250-300 m 3 And h, introducing nitrogen into the RH furnace circulating pipe in the baking process, wherein the nitrogen circulates in the RH furnace circulating pipe, and the circulating flow of the nitrogen is 500-800L/min.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102719593A (en) * | 2011-03-29 | 2012-10-10 | 鞍钢股份有限公司 | Method for smelting ultra-low carbon steel |
| CN107699654A (en) * | 2017-09-25 | 2018-02-16 | 南京钢铁股份有限公司 | A kind of smelting process of ultra-low-carbon steel desulfurization rapidly |
| CN109913607A (en) * | 2019-03-13 | 2019-06-21 | 河钢股份有限公司承德分公司 | A kind of smelting process of ultra-low-carbon steel |
| CN110468257A (en) * | 2019-09-12 | 2019-11-19 | 马鞍山钢铁股份有限公司 | It is a kind of suitable for low-carbon, the ladle top slag method for modifying of ultra-low-carbon steel |
| CN110484681A (en) * | 2018-03-27 | 2019-11-22 | 上海梅山钢铁股份有限公司 | A kind of production method of low carbon low silicon aluminium killed steel water |
| WO2020093710A1 (en) * | 2018-11-08 | 2020-05-14 | 南京钢铁股份有限公司 | High-purity acid-resistant pipeline steel smelting process |
-
2020
- 2020-07-10 CN CN202010663802.6A patent/CN113913580B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102719593A (en) * | 2011-03-29 | 2012-10-10 | 鞍钢股份有限公司 | Method for smelting ultra-low carbon steel |
| CN107699654A (en) * | 2017-09-25 | 2018-02-16 | 南京钢铁股份有限公司 | A kind of smelting process of ultra-low-carbon steel desulfurization rapidly |
| CN110484681A (en) * | 2018-03-27 | 2019-11-22 | 上海梅山钢铁股份有限公司 | A kind of production method of low carbon low silicon aluminium killed steel water |
| WO2020093710A1 (en) * | 2018-11-08 | 2020-05-14 | 南京钢铁股份有限公司 | High-purity acid-resistant pipeline steel smelting process |
| CN109913607A (en) * | 2019-03-13 | 2019-06-21 | 河钢股份有限公司承德分公司 | A kind of smelting process of ultra-low-carbon steel |
| CN110468257A (en) * | 2019-09-12 | 2019-11-19 | 马鞍山钢铁股份有限公司 | It is a kind of suitable for low-carbon, the ladle top slag method for modifying of ultra-low-carbon steel |
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