CN101962701B - LT-CAS (Control Automatic System) double-station vacuum refining device and process method thereof - Google Patents
LT-CAS (Control Automatic System) double-station vacuum refining device and process method thereof Download PDFInfo
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- CN101962701B CN101962701B CN2010102570425A CN201010257042A CN101962701B CN 101962701 B CN101962701 B CN 101962701B CN 2010102570425 A CN2010102570425 A CN 2010102570425A CN 201010257042 A CN201010257042 A CN 201010257042A CN 101962701 B CN101962701 B CN 101962701B
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Abstract
The invention belongs to the technical field of steelmaking and refining and in particular relates to an LT-CAS (Control Automatic System) double-station vacuum refining device and a process method thereof. The device comprises an LT refining device, a CAS refining device and a bottom blowing argon stirring system, wherein the LT refining device and the CAS refining device are arranged on parallel processing stations and connected with the bottom blowing argon stirring system through pipelines; when the bottom blowing and stirring functions of the CAS refining device are realized, a master argon valve is turned on, and then the valve of the CAS refining device is turned on; and when the LT refining device is used for smelting an ordinary hot rolled plate, the master argon valve is turned on firstly, and then the valve of the LT refining device is turned on. By adopting the technical scheme, the requirements ([S] is smaller than or equal to 50ppm) for producing cold rolled sheets, ultra-low sulfur hot rolling strip steel and medium-thickness plates of a steel making factory are met, wherein the CAS station is used for producing the cold rolled sheets, and the LT station is used for producing the ultra-low sulfur hot rolling strip steel and the medium-thickness plates so as to achieve the purposes of low-cost and ultra-low vulcanization to meet the requirement on production and the low-cost, high-efficiency and large-scale production.
Description
Technical field
The invention belongs to technical field of steelmaking and refining; Relate in particular to a kind of requirement ([S]≤50ppm) that steelworks is produced cold rolled sheet and super low sulfur hot rolled strip and plate of satisfying; CAS station wherein is used to produce cold rolled sheet; And the LT station is used for production super low sulfur hot rolled strip and plate, realizes the ultralow cheaply sulfurized LT-CAS of common hot-rolled product double equipment for vacuum refining and process method thereof.
Background technology
Some steel mills produce the more employing of common hot-rolled and cold-rolled product CAS furnace outer refining process at present.The CAS method of refining can solve the violent stirring molten steel preferably and promote inclusion floating and prevent that molten steel is by the contradiction of slag and furnace gas oxidation.This mainly is because employing CAS technology is carried out refining, is blown into argon gas by the ladle bottom earlier; After molten steel surface blows out a no slag " bright face "; Again impregnating cover is inserted molten steel, thereby can molten steel surface exposed part and slag that Argon causes be separated, and be under the interior Ar atmosphere protection of cover.Owing to have this characteristics, the CAS refinery practice can adopt strong Argon to stir, thereby can obtain good promotion deoxidation products Al
2O
3Polymerization, come-up, removal effect, thereby be fit to very much produce the cold rolled sheet product, this is confirmed (iron and steel, 2005 by productions such as Japanese Nippon Steel, Anshan iron and steel plant, Baosteels; 40 [10]: p1).But CAS is not suitable for and produces the hot-rolled steel sheet product; This mainly is because the slag major part is outside impregnating cover in the ladle, even if carry out violent stirring, also mainly is confined to the stirring to molten steel in covering; Because the desulfurization dynamic conditions is not enough; Therefore CAS technology can not be carried out desulfurization basically, however hot-rolled steel sheet require usually to have than low sulfur content, and the ultralow sulfurized trend of hot-rolled steel sheet can become more obvious from now on.
More external at present high-level steel mills produce the hot-rolled steel sheet product and often adopt ladle argon-blown+slag making refinery practice to carry out desulfurization; Adopt ladle argon-blown+slagging process mode to carry out refining desulfuration like Thyssen Iron And Steel Company; Pu item factory of Korea S Pohang Iron and Steel Corporation two STEELMAKING PRODUCTION slabs; The kind that only [S] content is lower than 20ppm just adopts the LF refinery practice, and other super low sulfur slab product all adopts ladle argon-blown+slag making refinery practice.The ladle argon-blown refining has bag end gas permeable brick Argon and top to insert jet pipe Argon dual mode; Combine with slag making, molten steel component adjustment, line feeding; Be referred to as LT technology (Ladle Treatment), except that desulfurization, also can be used for molten steel homogenizing, composition adjustment, remove inclusion etc.
Adopt the LT technology of the airtight Argon stirring of ladle stamp, slag making desulfurizing and refining function can ordinary hot rolled steel plate sulphur content be reduced to below the 50ppm, realize the ultralow cheaply sulfuration of common hot-rolled product.
Summary of the invention
In order to address the above problem, the purpose of this invention is to provide a kind of requirement that can satisfy steelworks production cold rolled sheet, can realize the LT-CAS double equipment for vacuum refining and the process method thereof of production super low sulfur hot rolled strip and plate requirement of products again.
Technical scheme of the present invention is: a kind of LT-CAS double equipment for vacuum refining, and this device comprises LT a refining unit, CAS a refining unit and argon bottom-blowing stirring system; Said LT a refining unit is made up of valve (1) ladle (3), sealing cover (7) and intake chute (8); Said CAS a refining unit is made up of valve (10), ladle (12), slag stop cone (4) and refractory materials impregnating cover (5); Wherein, Said ladle (3) and said ladle (12) are arranged on the parallel processing station; Said ladle (3) upper end is provided with sealing cover (7), and said sealing cover (7) is provided with said intake chute (8), and said ladle (3) bottom is connected with pipeline (9) through said valve (1); Said ladle (12) upper end is provided with said refractory materials impregnating cover (5) and said slag stop cone (4); Said refractory materials impregnating cover (5) is provided with alloy and adds hand-hole (6); The gas permeable brick (2) of said ladle (12) bottom is connected with said pipeline (9) through said valve (10), and said pipeline (9) is connected with the argon bottom-blowing stirring system through valve (11); At first open said valve (11), open said valve (1) then, thereby realize the bottom blowing agitating function of CAS a refining unit; When adopting the LT a refining unit to smelt common hot-rolled sheet, at first open said valve (11), and then Open valve said (10), realize LT refining ladle bottom blowing agitating function.
The present invention also provides the process method of above-mentioned equipment for vacuum refining, specifically may further comprise the steps:
1, the refinery practice of LT
(1) the strict pushing off the slag of converter tapping and add aluminium, alloy and 8kg/t slag charge at tapping process molten steel in ladle utilizes the stirring of tapping process steel flow to carry out deoxidation, slag making and comprise few partial desulfurization;
(2) stirring of 3～5min Argon is carried out to molten steel in wrapping in tapping end back, evenly molten steel and slag composition, and extraction molten steel and slag sample;
(3) add slag charge, aluminium, alloy etc. according to molten steel and the adjustment of slag sample constituents, the quantity of slag is controlled at 15～20kg/t;
(4) after the ladle stamp sealing, be blown into 600～800Nl/min argon gas by the bottom and carry out the strong mixing desulfurization.
2, the refinery practice of CAS
Carbon content during (1) with converter tapping in the control molten steel is 0.03-0.06%, and the dissolved oxygen content in the molten steel is 0.060-0.090%;
(2) after ladle was called in the CAS station, the strong blowing argon gas 1min in bottom blew behind the slag blanket of molten steel surface immediately cover down open, the thermometric sampling.
(3) add alloy, and continuous Argon stir process, pure Argon churning time is 15min.
The invention has the beneficial effects as follows:
Beneficial effect of the present invention is: owing to adopt technique scheme; The present invention adopts the LT-CAS double refinery practice of a shared cover BOTTOM ARGON BLOWING system; Satisfy steelworks and produce the requirement ([S]≤50ppm) of cold rolled sheet and super low sulfur hot rolled strip and plate; CAS station wherein is used to produce cold rolled sheet, and the LT station is used for production super low sulfur hot rolled strip and plate, realizes that the ultralow cheaply sulfuration of common hot-rolled product can satisfy the requirement of producing cold rolled sheet; Again can be low-cost, high-level efficiency and large batch of production super low sulfur hot rolled strip, plate product, thereby improve iron and steel enterprise's product competitiveness.
Description of drawings
Fig. 1 is the structural representation of LT-CAS double equipment for vacuum refining of the present invention.
Among the figure:
1. valve 7. sealing covers
2. gas permeable brick 8. intake chutes
3. ladle 9. pipelines
4. slag stop cone 10. valves
5. refractory materials impregnating cover 11. valves
6. alloy adds hand-hole 12. ladles
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is described further.
Be illustrated in figure 1 as LT-CAS double equipment for vacuum refining of the present invention.LT-CAS double equipment for vacuum refining as shown in Figure 1, this device comprises LT a refining unit, CAS a refining unit and argon bottom-blowing stirring system;
The LT a refining unit is made up of ladle 3, sealing cover 7 and intake chute 8; The CAS a refining unit is made up of ladle 12, slag stop cone 4 and refractory materials impregnating cover 5, and ladle 3 is arranged on the parallel processing station with ladle 12, and ladle 3 upper ends are provided with sealing cover 7, and sealing cover 7 is provided with intake chute 8, and ladle 3 bottoms are through valve 1
Be connected with pipeline 9; Ladle 12 upper ends are provided with refractory materials impregnating cover 5 and slag stop cone 4, and refractory materials impregnating cover 5 is provided with alloy and adds hand-hole 6, and the gas permeable brick 2 of ladle 12 bottoms is connected with pipeline 9 through valve 10, and pipeline 9 is connected with the argon bottom-blowing stirring system through valve 11.
Embodiment 1
Adopt device to produce ordinary hot rolled steel plate SPHC and cold-rolled steel sheet 08Al as a trial, wherein produce SPHC refining operation step (LT station) as follows:
(1) the strict pushing off the slag of converter tapping and add aluminium, alloy and 8kg/t slag charge at tapping process molten steel in ladle utilizes the stirring of tapping process steel flow to carry out deoxidation, slag making and comprise few partial desulfurization;
(2) stirring of 3min Argon is carried out to molten steel in wrapping in tapping end back, evenly molten steel and slag composition, and extraction molten steel and slag sample;
(3) add slag charge, aluminium, alloy etc. according to molten steel and the adjustment of slag sample constituents, the quantity of slag is controlled at 15～20kg/t;
(4) after the ladle stamp sealing, be blown into the 600Nl/min argon gas by the bottom and carry out the strong mixing desulfurization.
When adopting LT explained hereafter SPHC, refining desulfuration treatment time 15min, [S] content of handling in the finished steel of back is 50ppm, has successfully realized low cost, fast pace, large batch of production super low sulfur hot-rolled steel sheet.
The process step of production 08Al is (CAS station) as follows:
Carbon content during (1) with converter tapping in the control molten steel is 0.03-0.06%, and the dissolved oxygen content in the molten steel is 0.070-0.090%;
(2) after ladle was called in the CAS station, the strong blowing argon gas 1min in bottom blew behind the slag blanket of molten steel surface immediately cover down open, the thermometric sampling.
(3) add alloy, and continuous Argon stir process, pure Argon churning time is controlled at 15min.
The T.O content of molten steel is in 40-45 * 10 after the employing CAS refining
-6, the inclusion in the strand is mainly the tiny Al of size
2O
3Be mingled with, adopt the CAS refining to realize low-cost, the cold rolling carbon aluminium-killed steel of using of allegro smelting.
Embodiment 2:
Adopt this novel process to produce ordinary hot rolled steel plate SPHC and cold-rolled steel sheet 08Al as a trial, wherein produce SPHC refining operation step (LT station) as follows:
(1) the strict pushing off the slag of converter tapping and add aluminium, alloy and 8kg/t left and right sides slag charge at tapping process molten steel in ladle utilizes the stirring of tapping process steel flow to carry out deoxidation, slag making and comprise few partial desulfurization;
(2) stirring of 4min Argon is carried out to molten steel in wrapping in tapping end back, evenly molten steel and slag composition, and extraction molten steel and slag sample;
(3) add slag charge, aluminium, alloy etc. according to molten steel and the adjustment of slag sample constituents, the quantity of slag is controlled at 15～20kg/t;
(4) after the ladle stamp sealing, be blown into the 800Nl/min argon gas by the bottom and carry out the strong mixing desulfurization.
When adopting LT explained hereafter SPHC, refining desulfuration treatment time 15min, [S] content of handling in the finished steel of back is 40ppm, has successfully realized low cost, fast pace, large batch of production super low sulfur hot-rolled steel sheet.
The process step of production 08Al is (CAS station) as follows:
Carbon content during (1) with converter tapping in the control molten steel is 0.03-0.06%, and the dissolved oxygen content in the molten steel is 0.060-0.090%;
(2) after ladle was called in the CAS station, the strong blowing argon gas 1min in bottom blew behind the slag blanket of molten steel surface immediately cover down open, the thermometric sampling.
(3) add alloy, and continuous Argon stir process, pure Argon churning time is controlled at 15min.
The T.O content of molten steel is in 35-40 * 10 after the employing CAS refining
-6, the inclusion in the strand is mainly the tiny Al of size
2O
3Be mingled with, adopt the CAS refining to realize low-cost, the cold rolling carbon aluminium-killed steel of using of allegro smelting.
Embodiment 3:
Adopt this novel process to produce ordinary hot rolled steel plate SPHC and cold-rolled steel sheet 08Al as a trial, wherein produce SPHC refining operation step (LT station) as follows:
(1) the strict pushing off the slag of converter tapping and add aluminium, alloy and 8kg/t left and right sides slag charge at tapping process molten steel in ladle utilizes the stirring of tapping process steel flow to carry out deoxidation, slag making and comprise few partial desulfurization;
(2) the Argon stirring of the 5min left and right sides, evenly molten steel and slag composition, and extraction molten steel and slag sample are carried out to molten steel in wrapping in tapping end back;
(3) add slag charge, aluminium, alloy etc. according to molten steel and the adjustment of slag sample constituents, the quantity of slag is controlled at 15～20kg/t;
(4) after the ladle stamp sealing, be blown into the 600Nl/min argon gas by the bottom and carry out the strong mixing desulfurization.
When adopting LT explained hereafter SPHC, refining desulfuration treatment time 20min, [S] content of handling in the finished steel of back is 40ppm, has successfully realized low cost, fast pace, large batch of production super low sulfur hot-rolled steel sheet.
The process step of production 08Al is (CAS station) as follows:
Carbon content during (1) with converter tapping in the control molten steel is 0.03-0.06%, and the dissolved oxygen content in the molten steel is 0.060-0.080%;
(2) after ladle was called in the CAS station, the strong blowing argon gas 1min in bottom blew behind the slag blanket of molten steel surface immediately cover down open, the thermometric sampling.
(3) add alloy, and continuous Argon stir process, pure Argon churning time is controlled at 15min.
The T.O content of molten steel is in 40-45 * 10 after the employing CAS refining
-6, the inclusion in the strand is mainly the tiny Al of size
2O
3Be mingled with, adopt the CAS refining to realize low-cost, the cold rolling carbon aluminium-killed steel of using of allegro smelting.
Claims (2)
1. LT-CAS double equipment for vacuum refining, this device comprises LT a refining unit, CAS a refining unit and argon bottom-blowing stirring system; It is characterized in that said LT a refining unit is made up of first valve (1), first ladle (3), sealing cover (7) and intake chute (8); Said CAS a refining unit is made up of second valve (10), second ladle (12), slag stop cone (4) and refractory materials impregnating cover (5); Wherein, Said first ladle (3) and said second ladle (12) are arranged on the parallel processing station; Said first ladle (3) upper end is provided with sealing cover (7); Said sealing cover (7) is provided with said intake chute (8), and said first ladle (3) bottom is connected with pipeline (9) through said first valve (1); Said second ladle (12) upper end is provided with said refractory materials impregnating cover (5) and said slag stop cone (4); Said refractory materials impregnating cover (5) is provided with alloy and adds hand-hole (6); The gas permeable brick (2) of said second ladle (12) bottom is connected with said pipeline (9) through said second valve (10), and said pipeline (9) is connected with the argon bottom-blowing stirring system through the 3rd valve (11); At first open said the 3rd valve (11), open said first valve (1) then, thereby realize the bottom blowing agitating function of CAS a refining unit; When adopting the LT a refining unit to smelt common hot-rolled sheet, at first open said the 3rd valve (11), and then open said second valve (10), realize LT refining ladle bottom blowing agitating function.
2. the process method of LT-CAS double equipment for vacuum refining according to claim 1 is characterized in that, specifically may further comprise the steps:
1, the refinery practice of LT
(1) the strict pushing off the slag of converter tapping and add aluminium, alloy and 8kg/t slag charge at tapping process molten steel in ladle utilizes the stirring of tapping process steel flow to carry out deoxidation, slag making and comprise few partial desulfurization;
(2) stirring of 3～5min Argon is carried out to molten steel in wrapping in tapping end back, evenly molten steel and slag composition, and extraction molten steel and slag sample;
(3) add slag charge, aluminium, alloy according to molten steel and the adjustment of slag sample constituents, the quantity of slag is controlled at 15～20kg/t;
(4) after the ladle stamp sealing, be blown into 600～800Nl/min argon gas by the bottom and carry out the strong mixing desulfurization;
2, the refinery practice of CAS
Carbon during (1) with converter tapping in the control molten steel is 0.03-0.06%, and the dissolved oxygen in the molten steel is 0.060-0.090%;
(2) after ladle was called in the CAS station, the strong blowing argon gas 1min in bottom blew behind the slag blanket of molten steel surface immediately cover down open, the thermometric sampling;
(3) add alloy, and continuous Argon stir process, pure Argon churning time is 15min.
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| CN102337377A (en) * | 2011-08-23 | 2012-02-01 | 莱芜钢铁集团有限公司 | Molten steel wire feeding device and wire feeding method |
| CN102605239A (en) * | 2011-12-09 | 2012-07-25 | 首钢总公司 | Low sulfur steel and production method thereof |
| CN103184311B (en) * | 2013-03-12 | 2014-12-31 | 杭州联源重工机械有限公司 | Preparation method for producing high-strength cast steel slurry pump and special equipment thereof |
| CN103862014B (en) * | 2014-03-25 | 2016-10-12 | 莱芜钢铁集团有限公司 | The purifier of a kind of molten steel inclusion in removing continuous casting production and method of refining |
| CN103862013B (en) * | 2014-03-25 | 2016-02-17 | 莱芜钢铁集团有限公司 | A kind of refining cover for continuous casting production and preparation method thereof |
| CN105624367B (en) * | 2014-12-01 | 2017-07-21 | 鞍钢股份有限公司 | The purifier and method of a kind of control nitrogen content of molten steel |
| CN110982988B (en) * | 2019-12-25 | 2021-08-13 | 河钢股份有限公司承德分公司 | Desulfurization method for promoting contact of steel slag in LF refining furnace and steel-making method |
| CN111518992B (en) * | 2020-05-08 | 2022-02-08 | 赵元庆 | Tank type single-nozzle refining furnace and vacuum refining method |
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| JP3893770B2 (en) * | 1998-10-07 | 2007-03-14 | Ｊｆｅスチール株式会社 | Melting method of high clean ultra low carbon steel |
| CN2432219Y (en) * | 2000-06-09 | 2001-05-30 | 北京科技大学 | Multifunctional multiple blowing single nozzle refining furnace |
| CN100436603C (en) * | 2007-03-28 | 2008-11-26 | 北京科技大学 | Process of deoxygenating, desulfurizing and controlling non-metal inclusion content in steel |
| CN201292379Y (en) * | 2008-11-25 | 2009-08-19 | 长春电炉成套设备有限责任公司 | Four-upright post double-station transverse arm rotary refined-smelting ladle furnace |
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