CN110218839B - Deep desulfurization method in bearing steel smelting process - Google Patents
Deep desulfurization method in bearing steel smelting process Download PDFInfo
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 194
- 239000010959 steel Substances 0.000 title claims abstract description 194
- 238000000034 method Methods 0.000 title claims abstract description 73
- 238000006477 desulfuration reaction Methods 0.000 title claims abstract description 72
- 230000023556 desulfurization Effects 0.000 title claims abstract description 72
- 230000008569 process Effects 0.000 title claims abstract description 42
- 238000003723 Smelting Methods 0.000 title claims abstract description 40
- 239000002893 slag Substances 0.000 claims abstract description 125
- 238000007670 refining Methods 0.000 claims abstract description 78
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 76
- 229910052742 iron Inorganic materials 0.000 claims abstract description 38
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 34
- 238000010079 rubber tapping Methods 0.000 claims abstract description 28
- 238000005266 casting Methods 0.000 claims abstract description 13
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 11
- 238000009749 continuous casting Methods 0.000 claims abstract description 11
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 11
- 239000001301 oxygen Substances 0.000 claims abstract description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 76
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 39
- 229910052593 corundum Inorganic materials 0.000 claims description 39
- 229910001845 yogo sapphire Inorganic materials 0.000 claims description 39
- 229910052681 coesite Inorganic materials 0.000 claims description 38
- 229910052906 cristobalite Inorganic materials 0.000 claims description 38
- 239000000377 silicon dioxide Substances 0.000 claims description 38
- 229910052682 stishovite Inorganic materials 0.000 claims description 38
- 229910052905 tridymite Inorganic materials 0.000 claims description 38
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 23
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 23
- 239000004571 lime Substances 0.000 claims description 23
- 229910052782 aluminium Inorganic materials 0.000 claims description 21
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 21
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 20
- 229910045601 alloy Inorganic materials 0.000 claims description 18
- 239000000956 alloy Substances 0.000 claims description 18
- 229910052698 phosphorus Inorganic materials 0.000 claims description 18
- 239000000126 substance Substances 0.000 claims description 12
- 229910000519 Ferrosilicon Inorganic materials 0.000 claims description 10
- 229910052786 argon Inorganic materials 0.000 claims description 10
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 claims description 10
- 239000010436 fluorite Substances 0.000 claims description 10
- 238000010438 heat treatment Methods 0.000 claims description 10
- 239000000843 powder Substances 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 abstract description 16
- 239000011593 sulfur Substances 0.000 abstract description 16
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 abstract description 14
- 238000005189 flocculation Methods 0.000 abstract description 12
- 230000016615 flocculation Effects 0.000 abstract description 12
- 230000000694 effects Effects 0.000 abstract description 10
- 230000008901 benefit Effects 0.000 abstract description 5
- 230000014759 maintenance of location Effects 0.000 abstract description 4
- 239000002699 waste material Substances 0.000 abstract 1
- 238000005070 sampling Methods 0.000 description 16
- 239000005997 Calcium carbide Substances 0.000 description 9
- CLZWAWBPWVRRGI-UHFFFAOYSA-N tert-butyl 2-[2-[2-[2-[bis[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]amino]-5-bromophenoxy]ethoxy]-4-methyl-n-[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]anilino]acetate Chemical compound CC1=CC=C(N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)C(OCCOC=2C(=CC=C(Br)C=2)N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)=C1 CLZWAWBPWVRRGI-UHFFFAOYSA-N 0.000 description 9
- 238000005086 pumping Methods 0.000 description 8
- 230000007306 turnover Effects 0.000 description 7
- 239000007789 gas Substances 0.000 description 4
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910003112 MgO-Al2O3 Inorganic materials 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229910052755 nonmetal Inorganic materials 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
-
- 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
- C21C7/064—Dephosphorising; Desulfurising
-
- 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
-
- 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
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention discloses a deep desulfurization method in a bearing steel smelting process, which comprises the following steps: (1) pre-desulfurization of molten iron: the molten iron S is less than or equal to 0.015 percent after the pre-desulfurization; (2) smelting in a converter: the tapping temperature of the converter is more than or equal to 1650 ℃, the oxygen content is less than or equal to 400ppm, and the molten steel S at the end point of the converter is less than or equal to 0.015 percent; (3) refining in an LF furnace: the S content of the molten steel is less than or equal to 0.0020 percent after refining; (4) and (3) refining in an RH furnace: molten steel S entering the RH furnace is less than or equal to 0.0020 percent, RH vacuum retention time is more than or equal to 30min, and the molten steel is hoisted to a continuous casting machine for casting after finishing RH furnace refining. The invention effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the conditions of not increasing the refining treatment time of molten steel outside the furnace and widening the sulfur content of molten iron, waste steel, slag charge and the like, so that the sulfur content of the finished bearing steel is stabilized below 0.0015 percent, the stable production of deep desulfurization of the bearing steel is realized, and better economic benefit and social benefit are obtained.
Description
Technical Field
The invention belongs to the technical field of metallurgy, and particularly relates to a deep desulfurization method in a bearing steel smelting process.
Background
The bearing steel is mainly used for manufacturing balls, rollers, bearing rings and the like, is applied to mechanical rotating parts of various equipment, bears various shearing forces and heavy loads, and has strict requirements on chemical components, non-metal inclusion content and distribution, carbide and the like. The sulfur element is one of chemical components, not only causes hot brittleness of steel, but also increases surface cracks, reduces toughness, has great influence on Hydrogen Induced Cracks (HIC) and sulfide Stress Corrosion Cracks (SCC), has increasingly strict requirements on sulfur content, and requires that sulfur is less than 0.0015 percent, even less than 0.0005 percent in part of protocols.
In the production process of bearing steel, the sulfur content of raw materials such as molten iron, slag charge, scrap steel and the like is mainly controlled, and high-alkalinity slag refined outside a molten steel furnace is desulfurized. And the process of 'aluminum deoxidation plus high-alkalinity slag system with binary alkalinity larger than 15' is adopted in the refining process to realize the ultra-low sulfur. The slag in the process has stronger desulfurization capability, but the deoxidation product Al2O3、MgO-Al2O3The melting point is higher, if the casting process is not carried out, the water gap flocculation flow is caused, D-type and Ds-type inclusions are formed after the calcium treatment, the service life of the bearing steel is directly influenced, and the calcium treatment is forbidden by the industry standard requirement.
In order to avoid the problem of flocculation caused by a high-alkalinity slag system, a low-melting-point slag system with binary alkalinity of about 3.0 is generally adopted in the actual production process, the desulfurization efficiency of the slag system is limited, and even if the sulfur content in molten iron and slag is controlled, the sulfur content of a finished product is difficult to be below 0.0015% in the production process.
The production of ultra-low sulfur needs to be strictly controlled in terms of raw materials, for example, the S content in molten iron is below 0.005%, low-sulfur steel scraps and slag charges are used, and in addition, the modes of increasing the slag amount, secondarily slagging, prolonging the treatment time and the like need to be adopted in the external refining process of the molten steel furnace. The operation mode not only increases the smelting cost, but also seriously restricts the production organization and the smooth operation of the upper and lower procedures.
Aiming at the technical problems, a method for deep desulfurization in the bearing steel smelting process is developed by adjusting each operation procedure and the components of the refining slag, so that the sulfur content of the finished bearing steel is stabilized below 0.0015 percent under the condition of not increasing the refining treatment time of molten steel outside the furnace even if the sulfur content conditions of molten iron, slag, scrap steel and the like are relaxed, the casting performance is effectively controlled, and the method has important social and economic benefits.
Disclosure of Invention
The invention aims to solve the technical problem of providing a deep desulfurization method in the smelting process of bearing steel.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a deep desulfurization method for a bearing steel smelting process comprises the following steps:
(1) pre-desulfurization of molten iron: the S content of the molten iron is less than or equal to 0.015 percent after the molten iron is subjected to pre-desulfurization treatment;
(2) smelting in a converter: adding a carburant, an aluminum block, lime and synthetic slag in sequence during converter tapping, adding an alloy to adjust chemical components to a target content, controlling the initial binary alkalinity of the slag to be 3.5-4.5, wherein the slag comprises the following components: CaO: 45-50% of SiO2：10～15%、Al2O3: 28-32%, MgO: 6-8% of molten steel S at the end point of the converter is less than or equal to 0.015%;
(3) refining in an LF furnace: adding 4-6 kg/t steel of ferrosilicon powder and 4-6 kg/t steel of calcium carbide to the surface of the slag after the LF furnace enters the station, simultaneously adding lime and synthetic slag, and controlling the slagThe binary alkalinity of the slag is 5.0-6.0, and the slag comprises the following components: CaO: 50-55% of SiO2：9～11%、Al2O3: 22-26%, MgO: 6-8%; controlling the molten steel overturning area to be 300-400 mm by controlling the amount of bottom-blown argon in the refining process; 3-5 min before refining, adding 2-3 kg/t fluorite into steel, and electrifying and heating for 1-2 min; the molten steel S is less than or equal to 0.0020 percent after the refining of the LF furnace;
(4) and (3) refining in an RH furnace: molten steel S entering the RH furnace is less than or equal to 0.0020 percent, the RH furnace is vacuumized, the vacuum degree is 70-130 Pa, and the vacuum maintaining time is more than or equal to 30 min; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The adding amount of the aluminum blocks in the step (2) is controlled according to the Al content of the molten steel entering the LF furnace at 0.03-0.04%.
In the step (2), the adding amount of the carburant is 7.0-8.0kg/t of steel, and C in the carburant is more than or equal to 95%.
In the step (2), the addition amount of lime is 2.5-3.5 kg/t steel, and the addition amount of synthetic slag is 8.5-10.0 kg/t steel.
In the step (3), the addition amount of lime is 5.5-7.0 kg/t steel, and the addition amount of synthetic slag is 2.0-4.0 kg/t steel.
The synthetic slag in the steps (2) and (3) mainly comprises the following components: CaO: 45-50% of Al2O3：33～38%、SiO2：10～15%、MgO≤3.0%、S≤0.05%、P≤0.05%。
In the step (2), the tapping temperature of the converter is more than or equal to 1650 ℃, and the oxygen content of the tapped steel is less than or equal to 400 ppm.
In the step (4), S in the qualified molten steel is less than or equal to 0.0015 percent.
Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: the invention effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag by reasonably controlling the technological process under the conditions of not increasing the refining treatment time of molten steel outside the furnace and widening the sulfur content of molten iron, scrap steel, slag charge and the like, obtains low-sulfur molten steel, ensures that the sulfur content of the finished bearing steel is stabilized below 0.0015 percent, realizes the stable production of deep desulfurization of the bearing steel, and obtains better economic benefit and social benefit.
Detailed Description
The present invention will be described in further detail with reference to specific examples.
Example 1
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.015 percent;
(2) smelting in a converter: the tapping temperature of the converter is 1660 ℃, and the tapping oxygen content is 350 ppm; adding 7.5kg/t of carburant steel, an aluminum block, 2.7kg/t of lime steel, 9.0kg/t of synthetic slag steel and alloy into the converter during tapping, wherein the adding amount of the aluminum block is controlled according to the Al content in the LF furnace at 0.038%, adding the alloy to adjust chemical components to a target content, controlling the initial binary alkalinity of the slag at 4.0, and the slag comprises the following components: CaO: 47% SiO2：10%、Al2O3: 30%, MgO: 6 percent; converter end point S: 0.012%;
carburant C: 98 percent; the synthetic slag mainly comprises the following components: CaO: 48% of Al2O3：38%、SiO2：12%、MgO：3.0%、S：0.025%、P：0.0035%；
(3) Refining in an LF furnace: adding 5kg/t steel of ferrosilicon powder and 5kg/t steel of calcium carbide on the surface of the slag after the LF furnace enters the station; simultaneously adding 5.7kg/t steel of lime and 3.0kg/t steel of synthetic slag, controlling the binary alkalinity of the slag at 5.5, wherein the slag comprises the following components: CaO: 55% SiO2：10%、Al2O3: 25%, MgO: 8 percent; controlling the molten steel turnover area to be 350mm by controlling the amount of bottom-blown argon in the refining process; 3min before refining, adding fluorite 2.5kg/t steel, and electrifying and heating for 2 min; sampling S after refining: 0.0020 percent;
the synthetic slag mainly comprises the following components: CaO: 48% of Al2O3：38%、SiO2：12%、MgO：3.0%、S：0.025%、P：0.0035%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0020%, performing vacuum pumping on an RH furnace, keeping the vacuum degree at 70Pa for 32min, and performing off-station sampling S: 0.0015 percent; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0015 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Example 2
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.013%;
(2) smelting in a converter: the tapping temperature of the converter is 1650 ℃, and the oxygen content of the tapped steel is 330 ppm; adding 7.7kg/t of carburant steel, an aluminum block, 3.1kg/t of lime steel, 9.5kg/t of synthetic slag steel and alloy in sequence during converter tapping, wherein the adding amount of the aluminum block is controlled according to the Al content in the LF furnace at 0.040%, adding the alloy to adjust chemical components to a target content, controlling the initial binary alkalinity of the slag at 3.8, and the slag comprises the following components: CaO: 48% SiO2：11.5%、Al2O3: 31%, MgO: 7 percent; converter end point S: 0.010%;
carburant C: 96 percent; the synthetic slag mainly comprises the following components: CaO: 46% of Al2O3：35%、SiO2：13%、MgO：2.8%、S：0.035%、P：0.015%；
(3) Refining in an LF furnace: after the LF furnace enters the station, 4.5kg/t steel of ferrosilicon powder and 4.5kg/t steel of calcium carbide are added on the surface of the slag; simultaneously adding 6.0kg/t steel of lime and 3.5kg/t steel of synthetic slag, controlling the binary alkalinity of the slag at 5.2, wherein the slag comprises the following components: CaO: 53% SiO2：9.8%、Al2O3: 23%, MgO: 7 percent; controlling the molten steel turnover area to be 330mm by controlling the amount of bottom-blown argon in the refining process; 3.5min before refining, adding fluorite 2.7kg/t steel, and electrifying and heating for 1.5 min; sampling S after refining: 0.0018%;
the synthetic slag mainly comprises the following components: CaO: 46% of Al2O3：35%、SiO2：13%、MgO：2.8%、S：0.035%、P：0.015%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0018%, performing vacuum pumping by an RH furnace, wherein the vacuum degree is 80Pa, the vacuum retention time is 31min, and performing off-station sampling S: 0.0010%; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0010 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Example 3
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.012%;
(2) smelting in a converter: the tapping temperature of the converter is 1655 ℃, and the tapping oxygen content is 370 ppm; 7.6kg/t of carburant steel, aluminum blocks, 2.9kg/t of lime steel, 9.7kg/t of synthetic slag steel and alloy are sequentially added during converter tapping, the adding amount of the aluminum blocks is controlled according to the Al content entering the LF furnace at 0.032%, the alloy is added to adjust chemical components to target content, the initial binary alkalinity of the slag is controlled at 4.2, and the slag comprises the following components: CaO: 46% SiO2：12%、Al2O3: 29%, MgO: 6.5 percent; converter end point S: 0.010%;
carburant C: 96.5 percent; the synthetic slag mainly comprises the following components: CaO: 49% of Al2O3：37%、SiO2：12.5%、MgO：2.7%、S：0.028%、P：0.0045%；
(3) Refining in an LF furnace: adding 5.5kg/t ferrosilicon powder and 5.5kg/t calcium carbide into the surface of the slag after the LF furnace enters the station; simultaneously, 6.5kg/t of steel of lime and 2.3kg/t of steel of synthetic slag are added, the binary alkalinity of the slag is controlled to be 5.7, and the components of the slag are as follows: CaO: 51% SiO2：10.5%、Al2O3: 24%, MgO: 6.5 percent; controlling the molten steel turnover area to be 380mm by bottom-blown argon gas quantity in the refining process; 4min before refining, adding fluorite 2.3kg/t steel, and electrifying and heating for 1.2 min; sampling S after refining: 0.0020 percent;
the synthetic slag mainly comprises the following components: CaO: 49% of Al2O3：37%、SiO2：12.5%、MgO：2.7%、S：0.028%、P：0.0045%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0020%, performing vacuum pumping on an RH furnace, keeping the vacuum degree at 75Pa for 35min, and performing off-station sampling S: 0.0011%; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0011 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Example 4
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.011 percent;
(2) smelting in a converter: the tapping temperature of the converter is 1665 ℃, and the tapping oxygen content is 320 ppm; 7.8kg/t of carburant steel, aluminum blocks, 3.3kg/t of lime steel, 9.8kg/t of synthetic slag steel and alloy are sequentially added during converter tapping, the adding amount of the aluminum blocks is controlled according to the Al content in the LF furnace at 0.035%, the alloy is added to adjust chemical components to target content, the initial binary alkalinity of the slag is controlled at 4.3, and the slag components are as follows: CaO: 49% SiO2：13%、Al2O3: 31.5%, MgO: 7.5 percent; converter end point S: 0.010%;
carburant C: 95 percent; the synthetic slag mainly comprises the following components: CaO: 45% of Al2O3：36%、SiO2：10%、MgO：2.0%、S：0.022%、P：0.0025%；
(3) Refining in an LF furnace: after the LF furnace enters the station, adding 4.3kg/t ferrosilicon powder and 4.3kg/t calcium carbide steel into the surface of the slag; simultaneously adding 5.9kg/t steel of lime and 3.2kg/t steel of synthetic slag, controlling the binary alkalinity of the slag at 5.6, wherein the slag comprises the following components: CaO: 54% SiO2：10.2%、Al2O3: 22.5%, MgO: 7.5 percent; controlling the molten steel turnover area to be 360mm by controlling the amount of bottom-blown argon in the refining process; 4.5min before refining, adding fluorite 2.9kg/t steel, and electrifying and heating for 1.7 min; sampling S after refining: 0.0018%;
the synthetic slag mainly comprises the following components: CaO: 45% of Al2O3：36%、SiO2：10%、MgO：2.0%、S：0.022%、P：0.0025%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0018%, performing vacuum pumping on an RH furnace, wherein the vacuum degree is 80Pa, the vacuum retention time is 33min, and performing off-station sampling S: 0.0013 percent; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0013 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Example 5
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.014%;
(2) smelting in a converter: the tapping temperature of the converter is 1670 ℃, and the oxygen content of the tapped steel is 360 ppm; 7.9kg/t of carburant steel, an aluminum block, 2.8kg/t of lime steel, 8.5kg/t of synthetic slag steel and alloy are sequentially added during converter tapping, the adding amount of the aluminum block is controlled according to the Al content in the LF furnace at 0.036%, the alloy is added to adjust chemical components to target content, the initial binary alkalinity of the slag is controlled at 3.7, and the slag comprises the following components: CaO: 46.5% of SiO2：14.8%、Al2O3: 30.5%, MgO: 6.3 percent; converter end point S: 0.012%;
carburant C: 95.5 percent; the synthetic slag mainly comprises the following components: CaO: 47% of Al2O3：34%、SiO2：14%、MgO：2.4%、S：0.045%、P：0.025%；
(3) Refining in an LF furnace: adding 5.7kg/t ferrosilicon powder and 5.7kg/t calcium carbide into the surface of the slag after the LF furnace enters the station; simultaneously adding 6.3kg/t steel of lime and 2.7kg/t steel of synthetic slag, controlling the binary alkalinity of the slag at 5.3, wherein the slag comprises the following components: CaO: 52% SiO2：9.8%、Al2O3: 24.5%, MgO: 6.7 percent; controlling the molten steel turnover area to be 310mm by bottom argon blowing quantity in the refining process; 3.2min before refining, adding fluorite 2.1kg/t steel, and electrifying and heating for 1.6 min; sampling S after refining: 0.0019%；
The synthetic slag mainly comprises the following components: CaO: 47% of Al2O3：34%、SiO2：14%、MgO：2.4%、S：0.045%、P：0.025%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0019%, performing vacuum pumping on an RH furnace, keeping the vacuum degree at 85Pa for 38min, and performing off-station sampling S: 0.0014%; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0014 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Example 6
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.0125 percent;
(2) smelting in a converter: the tapping temperature of the converter is 1680 ℃, and the tapping oxygen content is 390 ppm; adding 8.0kg/t of carburant, 8.0kg/t of steel, aluminum blocks, 3.2kg/t of lime, 9.0kg/t of steel and alloy into the steel tapping of the converter in sequence, controlling the adding amount of the aluminum blocks according to the Al content in the LF furnace at 0.039%, adding the alloy to adjust chemical components to target content, controlling the initial binary alkalinity of the slag at 4.1, and comprising the following slag components: CaO: 48.3% and SiO2：12.7%、Al2O3: 28.6%, MgO: 7.2 percent; converter end point S: 0.010%;
carburant C: 97.5 percent; the synthetic slag mainly comprises the following components: CaO: 46.5% of Al2O3：34.5%、SiO2：11.5%、MgO：2.2%、S：0.015%、P：0.0015%；
(3) Refining in an LF furnace: after the LF furnace enters the station, adding 4.9kg/t steel of ferrosilicon powder and 4.9kg/t steel of calcium carbide on the surface of the slag; simultaneously, 6.8kg/t of steel of lime and 2.1kg/t of steel of synthetic slag are added, the binary alkalinity of the slag is controlled to be 5.4, and the components of the slag are as follows: CaO: 53.6% SiO2：10.3%、Al2O3: 25.1%, MgO: 7.7 percent; molten steel control by bottom blowing argon gas amount in refining processThe billowing area is 390 mm; 3.8min before refining, adding fluorite 2.4kg/t steel, and electrifying and heating for 1.4 min; sampling S after refining: 0.0018%;
the synthetic slag mainly comprises the following components: CaO: 46.5% of Al2O3：34.5%、SiO2：11.5%、MgO：2.2%、S：0.015%、P：0.0015%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0018%, performing vacuum pumping on an RH furnace, wherein the vacuum degree is 90Pa, the vacuum retention time is 37min, and performing off-station sampling S: 0.0012%; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0012 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Example 7
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.0138 percent;
(2) smelting in a converter: the tapping temperature of the converter is 1675 ℃, and the tapping oxygen content is 380 ppm; adding 7.3kg/t of carburant steel, aluminum blocks, 2.5kg/t of lime steel, 8.5kg/t of synthetic slag steel and alloy into the converter during tapping, wherein the adding amount of the aluminum blocks is controlled according to the Al content in the LF furnace at 0.033%, adding the alloy to adjust chemical components to a target content, controlling the initial binary alkalinity of the slag at 3.5, and the slag comprises the following components: CaO: 45% SiO2：15%、Al2O3: 28%, MgO: 6.9 percent; converter end point S: 0.010%;
carburant C: 98 percent; the synthetic slag mainly comprises the following components: CaO: 47.3% of Al2O3：35.7%、SiO2：14.2%、MgO：2.5%、S：0.032%、P：0.010%；
(3) Refining in an LF furnace: adding ferrosilicon powder 4kg/t steel and calcium carbide 4kg/t steel into the surface of the slag after the LF furnace enters the station; simultaneously adding 5.5kg/t steel of lime and 4.0kg/t steel of synthetic slag, controlling the binary alkalinity of the slag at 5.0, wherein the slag comprises the following components: CaO: 52.6%、SiO2：11%、Al2O3: 22%, MgO: 7.9 percent; controlling the molten steel turnover area to be 300mm by bottom-blown argon gas quantity in the refining process; 4.7min before refining, adding fluorite 3.0kg/t steel, and electrifying and heating for 1.3 min; sampling S after refining: 0.0019%;
the synthetic slag mainly comprises the following components: CaO: 47.3% of Al2O3：35.7%、SiO2：14.2%、MgO：2.5%、S：0.032%、P：0.010%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0019%, performing vacuum pumping on an RH furnace, keeping the vacuum degree at 115Pa for 40min, and performing off-station sampling S: 0.0010%; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0010 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Example 8
The method for deep desulfurization in the smelting process of the bearing steel comprises the following steps:
(1) pre-desulfurization of molten iron: molten iron S after the molten iron pre-desulfurization treatment is finished: 0.015 percent;
(2) smelting in a converter: the tapping temperature of the converter is 1690 ℃, and the tapping oxygen content is 400 ppm; 7.0kg/t of carburant steel, aluminum blocks, 3.5kg/t of lime steel, 10.0kg/t of synthetic slag steel and alloy are sequentially added during converter tapping, the adding amount of the aluminum blocks is controlled according to the Al content in the LF furnace at 0.030 percent, the alloy is added to adjust chemical components to target content, the initial binary alkalinity of the slag is controlled at 4.5, and the slag comprises the following components: CaO: 50% SiO2：12%、Al2O3: 32%, MgO: 8 percent; converter end point S: 0.015 percent;
carburant C: 97 percent; the synthetic slag mainly comprises the following components: CaO: 50% of Al2O3：33%、SiO2：15%、MgO：2.2%、S：0.05%、P：0.05%；
(3) Refining in an LF furnace: 6kg/t steel of ferrosilicon powder and 6kg/t steel of calcium carbide are added to the surface of the slag after the LF furnace enters the station; at the same time addLime 7.0kg/t steel and synthetic slag 2.0kg/t steel are added, the binary alkalinity of the slag is controlled to be 6.0, and the slag comprises the following components: CaO: 50% SiO2：9%、Al2O3: 26%, MgO: 6 percent; controlling the molten steel turnover area to be 400mm by bottom-blown argon gas quantity in the refining process; adding fluorite 2.0kg/t steel 5min before refining, and electrifying and heating for 1.0 min; sampling S after refining: 0.0015 percent;
the synthetic slag mainly comprises the following components: CaO: 50% of Al2O3：33%、SiO2：15%、MgO：2.2%、S：0.05%、P：0.05%；
(4) And (3) refining in an RH furnace: s after the RH furnace enters the station: 0.0015%, performing vacuum pumping on an RH furnace, keeping the vacuum degree at 130Pa for 30min, and performing off-station sampling S: 0.0013 percent; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
The molten steel S treated by the deep desulfurization method in the smelting process of the bearing steel of the embodiment is as follows: 0.0013 percent, effectively avoids the problems of flocculation flow of high-alkalinity slag and poor desulfurization effect of low-alkalinity slag under the condition of not increasing the refining treatment time of molten steel outside the furnace, and realizes the stable production of deep desulfurization of bearing steel.
Although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that: modifications and equivalents may be made thereto without departing from the spirit and scope of the invention and it is intended to cover in the claims the invention as defined in the appended claims.
Claims (5)
1. The deep desulfurization method for the bearing steel smelting process is characterized by comprising the following steps of:
(1) pre-desulfurization of molten iron: the S content of the molten iron is less than or equal to 0.015 percent after the molten iron is subjected to pre-desulfurization treatment;
(2) smelting in a converter: adding a carburant, an aluminum block, lime and synthetic slag in sequence during converter tapping, adding an alloy to adjust chemical components to a target content, controlling the initial binary alkalinity of the slag to be 3.5-4.5, wherein the slag comprises the following components: CaO: 45-50% of SiO2：10～15%、Al2O3: 28-32%, MgO: 6-8% of molten steel S at the end point of the converter is less than or equal to 0.015%; the lime addition amount is 2.5-3.5 kg/t steel, and the synthetic slag addition amount is 8.5-10.0 kg/t steel.
(3) Refining in an LF furnace: 4-6 kg/t steel of ferrosilicon powder, 4-6 kg/t steel of carbide are added to the slag surface after LF stove is come to a station, add lime, synthetic slag simultaneously, and the binary basicity of control slag is 5.0-6.0, and the slag component is: CaO: 50-55% of SiO2：9～11%、Al2O3: 22-26%, MgO: 6-8%; controlling the molten steel overturning area to be 300-400 mm by controlling the amount of bottom-blown argon in the refining process; 3-5 min before refining, adding 2-3 kg/t fluorite into steel, and electrifying and heating for 1-2 min; the molten steel S is less than or equal to 0.0020 percent after the refining of the LF furnace; the adding amount of lime is 5.5-7.0 kg/t steel, and the adding amount of synthetic slag is 2.0-4.0 kg/t steel;
the synthetic slag in the steps (2) and (3) mainly comprises the following components: CaO: 45-50% of Al2O3：33～38%、SiO2：10～15%、MgO≤3.0%、S≤0.05%、P≤0.05%。
(4) And (3) refining in an RH furnace: molten steel S entering the RH furnace is less than or equal to 0.0020 percent, the RH furnace is vacuumized, the vacuum degree is 70-130 Pa, and the vacuum maintaining time is more than or equal to 30 min; and (4) obtaining qualified molten steel after the RH furnace refining is finished, and hoisting the molten steel to a continuous casting machine for casting.
2. The method for deep desulfurization in the smelting process of bearing steel as claimed in claim 1, wherein the adding amount of the aluminum blocks in the step (2) is controlled in the range of 0.03-0.04% based on the Al content of the molten steel entering the LF furnace.
3. The method for deep desulfurization in the smelting process of bearing steel according to claim 1, wherein in the step (2), the addition amount of the carburant is 7.0-8.0kg/t steel, and C in the carburant is more than or equal to 95%.
4. The method for deep desulfurization during the smelting process of bearing steel according to any one of claims 1 to 3, wherein in the step (2), the tapping temperature of the converter is more than or equal to 1650 ℃, and the oxygen content of the tapping is less than or equal to 400 ppm.
5. The method for deep desulfurization in the smelting process of bearing steel according to any one of claims 1 to 3, wherein in the step (4), S in qualified molten steel is less than or equal to 0.0015%.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06145883A (en) * | 1992-11-02 | 1994-05-27 | Daido Steel Co Ltd | High purity bearing steel and its production |
| CN104087719A (en) * | 2014-07-04 | 2014-10-08 | 常州东大中天钢铁研究院有限公司 | Smelting process of high-carbon bearing steel |
| CN105463150A (en) * | 2015-12-18 | 2016-04-06 | 中天钢铁集团有限公司 | Steel smelting process used for automobile hub bearing |
| CN109402327A (en) * | 2018-11-22 | 2019-03-01 | 江阴兴澄特种钢铁有限公司 | A kind of external refining production method of super clean high-carbon-chromium bearing steel |
| CN109680122A (en) * | 2019-02-15 | 2019-04-26 | 江苏利淮钢铁有限公司 | A kind of hub bearing steel and its manufacturing method |
-
2019
- 2019-06-21 CN CN201910542589.0A patent/CN110218839B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06145883A (en) * | 1992-11-02 | 1994-05-27 | Daido Steel Co Ltd | High purity bearing steel and its production |
| CN104087719A (en) * | 2014-07-04 | 2014-10-08 | 常州东大中天钢铁研究院有限公司 | Smelting process of high-carbon bearing steel |
| CN105463150A (en) * | 2015-12-18 | 2016-04-06 | 中天钢铁集团有限公司 | Steel smelting process used for automobile hub bearing |
| CN109402327A (en) * | 2018-11-22 | 2019-03-01 | 江阴兴澄特种钢铁有限公司 | A kind of external refining production method of super clean high-carbon-chromium bearing steel |
| CN109680122A (en) * | 2019-02-15 | 2019-04-26 | 江苏利淮钢铁有限公司 | A kind of hub bearing steel and its manufacturing method |
Non-Patent Citations (1)
| Title |
|---|
| LF-RH工艺生产极低硫钢硫含量控制分析;丁小明 等;《炼钢》;20130228;第29卷(第1期);全文 * |
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