CN102994686A - Technology for smelting ER70S-6 welding wire steel through utilizing vanadium-containing molten iron - Google Patents
Technology for smelting ER70S-6 welding wire steel through utilizing vanadium-containing molten iron Download PDFInfo
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- CN102994686A CN102994686A CN2012104776173A CN201210477617A CN102994686A CN 102994686 A CN102994686 A CN 102994686A CN 2012104776173 A CN2012104776173 A CN 2012104776173A CN 201210477617 A CN201210477617 A CN 201210477617A CN 102994686 A CN102994686 A CN 102994686A
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Abstract
The invention relates to a technology for smelting an ER70S-6 welding wire steel through utilizing vanadium-containing molten iron, which belongs to the technical field of metallurgy. The technical scheme is as follows: the vanadium-containing molten iron is taken as a raw material for converter vanadium extracting, semisteel refining, ladle furnace (LF) refining, continuous casting and steel rolling. The technology has the beneficial effects that the vanadium in the vanadium-containing molten iron is fully used, the chemical ingredients of the ER70S-6 welding wire steel are redesigned, a deoxidation technology is optimized, is a refining process mixed with less Al2O3 and only uses ferrosilicon powder for diffusible desoxydation, any material which contains Ca is not added during the whole smelting process, so that sparks are reduced during a welding process; and a certain amount of residual vanadium is controlled to exist in the welding wire steel, double functions of grain refining and precipitation strengthening of the vanadium in the steel are played, and the steel strength and the steel toughness are improved.
Description
Technical field
The present invention relates to a kind of technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel, belong to metallurgical technology field.
Background technology
At present; shielded welding is to utilize adscititious gases as the electric arc medium and protect electric arc and the electric-arc welding of welding zone; obtained using more and more widely in manufacturings such as China's heavy-duty machinery, engineering machinery, boats and ships, boiler, vehicles; progressively replaced the welding rod protection weldering of poor efficiency, the solder wire material that shielded welding uses is commonly the ER70S-6 welding wire steel.Contain the dual function that a certain amount of vanadium can play crystal grain thinning and precipitation strength in the ER70S-6 welding wire steel, the existence that is mainly reflected in vanadium in the steel can form thinner ferrite crystalline substance-pearlitic structure, thereby improves the toughness of heat affected zone.In addition, vanadium at high temperature has stronger intensity and shock resistance, corrosion-resistant and weldability as carbide and precipitation hardening agent; The ER70S-6 smelting steel method of background technology is with common molten iron smelting, and chemical composition content is: C:0.06%-0.15%, Mn:1.40%-1.85%, Si:0.80%-1.15%, P :≤0.025%, S≤0.035%; Existing problems are: as C, the intensity of welding wire steel was lower when the Mn composition was in lower limit, the effect of weaving silk is bad in the smelting process, and weld strength is also lower.
Summary of the invention
The object of the invention provides a kind of technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel, give full play to the effect of vanadium in the vanadium-bearing hot metal, redesign ER70S-6 welding wire steel chemical ingredients, by optimizing smelting technology, rationally control the remaining content of vanadium in the ER70S-6 welding wire steel, improve drawing property and the welding property of steel, solve the problems referred to above that background technology exists.
Technical scheme of the present invention is: a kind of technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel, comprise following operation: vanadium-bearing hot metal is that raw material carries out vanadium extraction by converter blowing, semi-steel making, LF refining, continuous casting and steel rolling, described vanadium-bearing hot metal is that raw material carries out the vanadium extraction by converter blowing operation, vanadium-bearing hot metal composition range weight percent is: C:3.5%-5.0%, Si:0.09%-0.47%, Mn:0.07%-0.19%, P:0.07%-0.12%, S:0.02%-0.07%, V:0.200%-0.500%, Ti:0.13%-0.52%, Cr:0.09%-0.41%; Vanadium-bearing hot metal is carried out vanadium extraction by converter blowing, and C, Si, Mn, P, S, V content are adjusted as follows: C:0.06%-0.10%, Mn:1.40%-1.60%, Si:0.80%-0.95%, P :≤0.025%, S≤0.035%, V:0.005%-0.015%.
Described semi-steel making operation, vanadium-bearing hot metal is processed through vanadium extraction, and oxygen supply 4min-6min uses pellet to do thermoregulation agent, terminal temperature is controlled at 1360-1420 ℃, obtain content of vanadium lower contain the vanadium half steel, its composition range weight percent is: C:3.50%-3.90%, Si+Ti: vestige, Mn:0.05%-0.12%, P:0.07%-0.12%, S:0.02%-0.07%, V:0.020%-0.050%.
The half steel that obtains after the vanadium-bearing hot metal vanadium extraction is blended into steel-making converter, adds slag material, when terminal point meets C:0.04%-0.06%, S≤0.030%, P≤0.015% weight percent, carries out the pushing off the slag tapping steel; Require to have calculated alloy addition according to steel grade in the tapping process, carry out the deoxidation alloying operation, use the deoxidation of sial barium, add small-particle lime and refining slag and carry out pre-slagging, carry out diffusive deoxidation with ferrosilicon powder; Alloy material, small-particle lime, refining slag, ferrosilicon powder addition sequence are alloy-small-particle lime-refining slag-ferrosilicon powder; The on-line argon-blow gas agitating, vanadium is controlled between the 0.005%-0.010%.
Described LF refining procedure adds lime, fluorite slag making in the refining process, the sealing bell, make and keep the pressure-fired atmosphere in the stove, argon bottom-blowing adopts weak stir mode between heating period, and the exposed diameter of molten steel is not more than 350mm, adds in batches ferrosilicon powder and makes reducing slag, the ferrosilicon powder overall control is at 0.6-1.0kg/t, the white slag hold-time is not less than 15 minutes, carries out the operation of soft blow argon after composition, temperature are hit, and the soft blow argon time is not less than 12 minutes, evenly composition and temperature promote inclusion floating; Composition Control was as follows when refining finished: C:0.06%-0.10%, Mn:1.40%-1.60%, Si:0.80%-0.95%, P :≤0.025%, S≤0.035%, V:0.005%-0.015%.
In the described semi-steel making operation, the pellet add-on is 20-30kg/t; Slag material is: lime, fluorite, light dolomite, and the rhombspar add-on is pressed 60% of lime adding amount; Sial barium reductor add-on is 0.2-0.4kg/t, and the small-particle lime adding amount is 3.0-4.0kg/t, refining slag 1.0-2.0kg/t, ferrosilicon powder 0.3-0.6kg/t; The argon gas air supply intensity is the 2-6L/mint steel.
In the described LF refining procedure, lime adding amount is 2.0-3.0kg/t, and the fluorite add-on is 25% of lime.The argon gas air supply intensity is between heating period: 1.2-2.0L/mint steel, soft blow air supply intensity are the 0.5-0.8L/mint steel; The ferrosilicon powder composition is: Si:72-80%, P :≤0.050%, S≤0.030%, the adding method is to add 0.2-0.4kg/t before the refining, once heat complete adding 0.2-0.4kg/t, the complete adding of second-heating 0.2-0.4kg/t adds overall control at 0.6-1.0kg/t.
Beneficial effect of the present invention: give full play to the effect of vanadium in the vanadium-bearing hot metal, redesign ER70S-6 welding wire steel chemical ingredients is optimized deoxidization technique, is less Al
2O
3Be mingled with refining process and only use the ferrosilicon powder diffusive deoxidation, whole smelting process is not added any Ca of containing material, reduces the welding process spark; And having the remaining vanadium of certain content in the control welding wire steel, the dual function of performance vanadium crystal grain thinning and precipitation strength in steel improves the intensity of steel, improves the toughness of steel.
Description of drawings
Fig. 1 is embodiment of the invention process flow sheet.
Embodiment
The present invention will be further described by the following examples.
Below be the embodiment of 100 tons of converter smelting ER70S-6 welding wires, wherein converter extracting vanadium is one, and two of steel-making converters have two LF ladle refining furnaces and two eight machines, eight stream billet casters behind the stove.
Embodiment 1:
Molten iron after vanadium extraction, C:3.78, V:0.031%, S:0.038%, Cr+Ni+Cu:0.042% is blended into steel-making converter, blow end point C:0.05%, P:0.012%, S:0.028%, meet the tapping requirement, tapping process adds sial barium reductor 0.3kg/ ton steel, lime 358kg, refining slag 142kg, the ferrosilicon powder add-on is 0.5kg/ ton steel, remaining content of vanadium 0.008%, Cr+Ni+Cu:0.017%; The refining of LF stove adds ferrosilicon powder 0.9kg/ ton; the refining of LF stove adds vanadium in the ferrosilicon powder 0.9kg/t reducing slag; content of vanadium increases by 0.003% in the steel; use carbon dust, ferrosilicon and low carbon ferromanganese to finely tune other composition; reach soft blow 12min after the finished product requirement; hang the continuous casting protective casting, strand properties after rolling satisfies the GB requirement.The finished product composition is: C:0.07%, Si:0.85%, Mn:1.47, P:0.014%, S:0.009%, V:0.011%.
Embodiment 2:
Molten iron after vanadium extraction, C:3.67, V:0.042%, S:0.035%, Cr+Ni+Cu:0.046% is blended into steel-making converter, blow end point C:0.04 %, P:0.010%, S:0.021%, meet the tapping requirement, tapping process adds sial barium reductor 0.4kg/ ton steel, lime 398kg, refining slag 145kg, the ferrosilicon powder add-on is 0.5kg/ ton steel, remaining content of vanadium 0.005%, Cr+Ni+Cu:0.014%; The refining of LF stove adds ferrosilicon powder 0.7kg/ ton; the refining of LF stove adds vanadium in the ferrosilicon powder 0.9kg/t reducing slag; content of vanadium increases by 0.004% in the steel; use carbon dust, ferrosilicon and low carbon ferromanganese to finely tune other composition; reach soft blow 12min after the finished product requirement; hang the continuous casting protective casting, strand properties after rolling satisfies the GB requirement.The finished product composition is: C:0.07%, Si:0.86%, Mn:1.46, P:0.015%, S:0.008%, V:0.005%.
Embodiment 3:
Molten iron after vanadium extraction, C:3.74, V:0.040%, S:0.033%, Cr+Ni+Cu:0.041% is blended into steel-making converter, blow end point C:0.06 %, P:0.011%, S:0.025%, meet the tapping requirement, tapping process adds sial barium reductor 0.2kg/ ton steel, lime 378kg, refining slag 167kg, the ferrosilicon powder add-on is 0.3kg/ ton steel, remaining content of vanadium 0.008%, Cr+Ni+Cu:0.019%; The refining of LF stove adds vanadium in the ferrosilicon powder 0.9kg/t reducing slag; content of vanadium increases by 0.006% in the steel, uses carbon dust, ferrosilicon and low carbon ferromanganese to finely tune other composition, reaches soft blow 12min after the finished product requirement; then hang the continuous casting protective casting, strand properties after rolling satisfies the GB requirement.The finished product composition is: C:0.08%, Si:0.88%, Mn:1.46, P:0.014%, S:0.009%, V:0.014%.
Embodiment 4:
Molten iron after vanadium extraction, C:3.47, V:0.046%, S:0.039%, Cr+Ni+Cu:0.047% is blended into steel-making converter, blow end point C:0.04 %, P:0.008%, S:0.030%, meet the tapping requirement, tapping process adds sial barium reductor 0.4kg/ ton steel, lime 377kg, refining slag 155kg, the ferrosilicon powder add-on is 0.6kg/ ton steel, remaining content of vanadium 0.005%, Cr+Ni+Cu:0.012%; The refining of LF stove adds ferrosilicon powder 1.0kg/ ton; the refining of LF stove adds vanadium in the ferrosilicon powder 0.9kg/t reducing slag; content of vanadium increases by 0.004% in the steel; use carbon dust, ferrosilicon and low carbon ferromanganese to finely tune other composition; reach soft blow 12min after the finished product requirement; hang the continuous casting protective casting, strand properties after rolling satisfies the GB requirement.The finished product composition is: C:0.07%, Si:0.85%, Mn:1.49, P:0.010%, S:0.005%, V:0.009%.
Claims (6)
1. technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel, it is characterized in that comprising following operation: vanadium-bearing hot metal is that raw material carries out vanadium extraction by converter blowing, semi-steel making, LF refining, continuous casting and steel rolling, described vanadium-bearing hot metal is that raw material carries out the vanadium extraction by converter blowing operation, vanadium-bearing hot metal composition range weight percent is: C:3.5%-5.0%, Si:0.09%-0.47%, Mn:0.07%-0.19%, P:0.07%-0.12%, S:0.02%-0.07%, V:0.200%-0.500%, Ti:0.13%-0.52%, Cr:0.09%-0.41%; Vanadium-bearing hot metal is carried out vanadium extraction by converter blowing, and C, Si, Mn, P, S, V content are adjusted as follows: C:0.06%-0.10%, Mn:1.40%-1.60%, Si:0.80%-0.95%, P :≤0.025%, S≤0.035%, V:0.005%-0.015%.
2. a kind of technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel according to claim 1, it is characterized in that described semi-steel making operation, vanadium-bearing hot metal is processed through vanadium extraction, oxygen supply 4min-6min, use pellet to do thermoregulation agent, terminal temperature is controlled at 1360-1420 ℃, obtain content of vanadium lower contain the vanadium half steel, its composition range weight percent is: C:3.50%-3.90%, Si+Ti: vestige, Mn:0.05%-0.12%, P:0.07%-0.12%, S:0.02%-0.07%, V:0.020%-0.050%.
3. a kind of technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel according to claim 2, it is characterized in that the half steel that obtains after the vanadium-bearing hot metal vanadium extraction is blended into steel-making converter, add slag material, when terminal point meets C:0.04-0.06%, S≤0.030%, P≤0.015% weight percent, carry out the pushing off the slag tapping steel; Require to have calculated alloy addition according to steel grade in the tapping process, carry out the deoxidation alloying operation, use the deoxidation of sial barium, add small-particle lime and refining slag and carry out pre-slagging, carry out diffusive deoxidation with ferrosilicon powder; Alloy material, small-particle lime, refining slag, ferrosilicon powder addition sequence are alloy-small-particle lime-refining slag-ferrosilicon powder, the on-line argon-blow gas agitating.
4. a kind of technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel according to claim 1 and 2 is characterized in that in the described semi-steel making operation, the pellet add-on is 20-30kg/t; Slag material is: lime, fluorite, light dolomite, and the rhombspar add-on is pressed 60% of lime adding amount; Sial barium reductor add-on is 0.2-0.4kg/t, and the small-particle lime adding amount is 3.0-4.0kg/t, refining slag 1.0-2.0kg/t, ferrosilicon powder 0.3-0.6kg/t; The argon gas air supply intensity is the 2-6L/mint steel.
5. a kind of technique of utilizing vanadium-bearing hot metal to smelt the ER70S-6 welding wire steel according to claim 1 and 2 is characterized in that in the described LF refining procedure, lime adding amount is 2.0-3.0kg/t, and the fluorite add-on is 25% of lime.
6. the argon gas air supply intensity is between heating period: 1.2-2.0L/mint steel, soft blow air supply intensity are the 0.5-0.8L/mint steel; The ferrosilicon powder composition is: Si:72-80%, P :≤0.050%, S≤0.030%, the adding method is to add 0.2-0.4kg/t before the refining, once heat complete adding 0.2-0.4kg/t, the complete adding of second-heating 0.2-0.4kg/t adds overall control at 0.6-1.0kg/t.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103320565A (en) * | 2013-06-19 | 2013-09-25 | 武汉钢铁(集团)公司 | Method for controlling P in smelted H08 welding wire |
| CN105861773A (en) * | 2015-01-23 | 2016-08-17 | 鞍钢股份有限公司 | Smelting method for controlling titanium and sulfur content of steel for high-titanium gas-shielded welding wire ER70S-G |
| CN106917046A (en) * | 2017-03-10 | 2017-07-04 | 河钢股份有限公司承德分公司 | A kind of method that utilization vanadium-bearing hot metal produces Steel for cold heading processing |
| CN107164605A (en) * | 2017-03-29 | 2017-09-15 | 河钢股份有限公司承德分公司 | A kind of LF refining method of deoxidation for producing low-carbon welding wire steel |
| CN108588326A (en) * | 2018-01-19 | 2018-09-28 | 河钢股份有限公司承德分公司 | A kind of method that vanadium-bearing hot metal smelts high strength welding wire steel ER80-G |
| CN109352209A (en) * | 2018-11-22 | 2019-02-19 | 湖南华菱湘潭钢铁有限公司 | A kind of production method of alloy welding wire steel |
| CN110172540A (en) * | 2019-04-30 | 2019-08-27 | 武汉钢铁有限公司 | A kind of low-sulfur titaniferous welding wire steel smelting process |
| CN111349755A (en) * | 2020-03-17 | 2020-06-30 | 本钢板材股份有限公司 | Direct supply silicon control process for SAE1006CrQZ steel grade |
| CN112760443A (en) * | 2020-12-16 | 2021-05-07 | 河钢股份有限公司承德分公司 | Control method for converter steelmaking of low-vanadium molten iron and application thereof |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103320565A (en) * | 2013-06-19 | 2013-09-25 | 武汉钢铁(集团)公司 | Method for controlling P in smelted H08 welding wire |
| CN105861773A (en) * | 2015-01-23 | 2016-08-17 | 鞍钢股份有限公司 | Smelting method for controlling titanium and sulfur content of steel for high-titanium gas-shielded welding wire ER70S-G |
| CN105861773B (en) * | 2015-01-23 | 2017-12-05 | 鞍钢股份有限公司 | Smelting method for controlling titanium and sulfur content of steel for high-titanium gas-shielded welding wire ER70S-G |
| CN106917046B (en) * | 2017-03-10 | 2019-01-25 | 河钢股份有限公司承德分公司 | A method of Steel for cold heading processing is produced using vanadium-bearing hot metal |
| CN106917046A (en) * | 2017-03-10 | 2017-07-04 | 河钢股份有限公司承德分公司 | A kind of method that utilization vanadium-bearing hot metal produces Steel for cold heading processing |
| CN107164605A (en) * | 2017-03-29 | 2017-09-15 | 河钢股份有限公司承德分公司 | A kind of LF refining method of deoxidation for producing low-carbon welding wire steel |
| CN108588326A (en) * | 2018-01-19 | 2018-09-28 | 河钢股份有限公司承德分公司 | A kind of method that vanadium-bearing hot metal smelts high strength welding wire steel ER80-G |
| CN109352209A (en) * | 2018-11-22 | 2019-02-19 | 湖南华菱湘潭钢铁有限公司 | A kind of production method of alloy welding wire steel |
| CN110172540A (en) * | 2019-04-30 | 2019-08-27 | 武汉钢铁有限公司 | A kind of low-sulfur titaniferous welding wire steel smelting process |
| CN111349755A (en) * | 2020-03-17 | 2020-06-30 | 本钢板材股份有限公司 | Direct supply silicon control process for SAE1006CrQZ steel grade |
| CN111349755B (en) * | 2020-03-17 | 2022-02-08 | 本钢板材股份有限公司 | Direct supply silicon control process for SAE1006CrQZ steel grade |
| CN112760443A (en) * | 2020-12-16 | 2021-05-07 | 河钢股份有限公司承德分公司 | Control method for converter steelmaking of low-vanadium molten iron and application thereof |
| CN112760443B (en) * | 2020-12-16 | 2022-06-28 | 河钢股份有限公司承德分公司 | Control method for converter steelmaking of low-vanadium molten iron and application thereof |
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Application publication date: 20130327 |