CN203292475U

CN203292475U - Four-hole type submersed nozzle used for FTSC sheet billet continuous casting crystallizer with high pulling speed

Info

Publication number: CN203292475U
Application number: CN201320271797XU
Authority: CN
Inventors: 陈永范; 李波; 李轼保; 李涛
Original assignee: Ustl Oriental Giant Advanced Ceramic Co ltd; University of Science and Technology Liaoning USTL
Current assignee: Ustl Oriental Giant Advanced Ceramic Co ltd; University of Science and Technology Liaoning USTL
Priority date: 2013-05-17
Filing date: 2013-05-17
Publication date: 2013-11-20
Anticipated expiration: 2023-05-17

Abstract

The utility model relates to the field of nozzles of metallurgy continuous casting devices, in particular to a four-hole type submersed nozzle used for an FTSC sheet billet continuous casting crystallizer with a high pulling speed. The four-hole type submersed nozzle comprises a liquid steel inflow end on the upper portion of the nozzle, a channel on the middle portion of the nozzle and an outflow end on the lower portion of the nozzle, wherein the liquid steel inflow end, the channel and the outflow end are connected in sequence, discharge holes are symmetrically formed in the two sides of the outflow end on the lower portion of the nozzle, middle flow guiding bodies are arranged in the discharge holes respectively, four discharge passageways are formed at the outflow end on the lower portion of the nozzle, and a diversion body is arranged between the discharge holes. The four-hole type submersed nozzle used for the FTSC sheet billet continuous casting crystallizer with the high pulling speed is characterized in that an arc concave portion is arranged on the top face of the diversion body. Compared with the prior art, the four-hole type submersed nozzle used for the FTSC sheet billet continuous casting crystallizer with the high pulling speed has the advantages that the lower portions of the four discharge holes are of a flat type structure, flowing of liquid steel around the nozzle is facilitated, a billet shell is prevented from being adhered to the nozzle in the solidification process, the structure and the size of the liquid steel inner passageways of the nozzle and the structure and the size of the outflow end are designed in an optimized mode, the vortex center positions of two symmetrical convolution areas which are formed in the portions, below the four passageways, of the two discharge holes are high, and the four-hole type submersed nozzle is particularly beneficial to enabling nonmetallic inclusions in liquid steel to float upward and be absorbed and removed by protective residues.

Description

High pulling rate FTSC crystallizer for continuous casting of thin slabs is with four cellular type submersed nozzles

Technical field

The utility model relates to field, the metallurgical continuous casting equipment mouth of a river, relates in particular to a kind of high pulling rate FTSC crystallizer for continuous casting of thin slabs with four cellular type submersed nozzles.

Background technology

The the Flexible Thin Slab Caster(FTSC of Italy Danieli Off Mecc exploitation) generally between 65～92mm, width is about 900～1650mm to the slab thickness of sheet blank continuous casting production.The FTSC thin-slab caster is different from conventional plate blank conticaster flat crystallizer commonly used, the crystallizer of FTSC thin-slab caster is similar with the CSP thin-slab caster, its wide copper coin all has the curved surface that is comprised of continuous arc transition, whole crystallizer is " funnel-form ", but " funnel " curve form size dimension of two kinds of crystallizers is different.Molten Steel In The Funnel-typed Mold molten bath upper space increases; make sheet blank continuous casting adopt submersed nozzle and continuous casting covering slag to become possibility; but funnel-form crystallizer internal upper part space increase amplitude is limited; therefore thin-slab caster generally will be processed into flat pattern with the molten steel outflow end of submersed nozzle, and namely its size along the crystallizer width is wanted obvious size greater than through-thickness.

The molten steel that submersed nozzle is connected with tundish flows into end and is generally tubular, thereby connection inflow end and outflow end is the tubular conduit of a smooth continuous transition of cross sectional shape.

In order to prevent molten steel generation secondary oxidation in continuous casting production process; need to add the solid particle covering slag on the crystallizer molten steel bath surface; it is contacted with high-temperature molten steel will absorb heat and melt; so just may make continuous casting covering slag play the protectant effect that prevents the molten steel secondary oxidation, the slag film that flows between solidified shell and copper plate of crystallizer can play the reduction resistance of billet withdrawal and absorb the effects such as non-metallic inclusion of floating from molten steel.Because the quality of slag film between continuous casting covering slag melting conditions and feeding copper plate of crystallizer and solidified shell has material impact to quality inside and outside continuous casting production direct motion and strand, this just requires the molten steel that forms in crystallizer from submersed nozzle convolution stream reasonably to take high-temperature molten steel to crystallizer molten bath top, is beneficial to guarantee reasonable fusing and the feeding of continuous casting covering slag; Simultaneously, to prevent that also stream causes the fluctuating of bath surface and the excessive covering slag that makes that fluctuates is involved in solidified shell or molten steel because the molten steel that forms from submersed nozzle circles round in crystallizer, and then cause slab quality problem and production accident.Therefore, the overall structure of submersed nozzle (especially the internal flow channel sectional area changes and molten steel outflow end structure) just plays effect of crucial importance at this.

, according to above-mentioned research and understanding to molten steel of melting bath motor behavior in the FTSC crystallizer for continuous casting of thin slabs, at present, produce the submersed nozzle four flat mouths of a river of perforate (referring to accompanying drawing 7, accompanying drawing 8) of adopting that the FTSC crystallizer of continuous slab casting machine is used both at home and abroad more.Quadripuntal SEN shown in Figure 7 directly is transported to high-temperature molten steel mouth of a river bath surface on every side by two holes (7) that upwards spue, realized preferably moving on the molten steel of melting bath high-temperature region, but due on the hole molten steel jet that spues comparatively serious to the impact of crystallizer molten steel bath surface fluctuation, and molten steel of melting bath face high-temperature region also only concentrates on around the mouth of a river, makes whole molten steel surface temperature skewness.Shown in Figure 8ly belong to improved four mouths of a river, immersion hole, hole, circular flow in the crystallizer that the molten steel jet that relies on molten steel jet that basic horizontal that the hole that upwards spues (7) on top forms flows out to suppress the hole that spues (8) downwards causes, the molten steel of melting bath ground roll is moving has certain amplitude to improve and make, but also caused the disadvantageous negative effect of non-metallic inclusion floating simultaneously, therefore be not suitable for the production of the demanding variety steel continuous casting of steel billet cleanliness factor.The casting speed of FTSC sheet blank continuous casting carries out high pulling rate while producing when brought up to 5.0～6.0m/min by present 4.0～4.5m/min, the adverse effect problem of above-mentioned existing submersed nozzle is more serious, thereby existing quadripuntal SEN can not adapt to the production of FTSC sheet billet high casting speed continuous casting.

Summary of the invention

The purpose of this utility model is to provide a kind of high pulling rate FTSC crystallizer for continuous casting of thin slabs with four cellular type submersed nozzles, be used for FTSC sheet blank continuous casting captain funnel-form crystallizer, by reducing to flow out the molten steel effluxvelocity from the submersed nozzle discharge opening, fluctuating and the fluctuation of bath surface in crystallizer while reducing high pulling rate production; Make on high-temperature region, Mold molten bath and move, promote the uniformity of nascent solidified shell, and the non-metallic inclusion floating that is conducive in molten steel is absorbed by continuous casting covering slag; Material structure intensity and the opposing high-temperature molten steel that can improve submersed nozzle bottom outflow end simultaneously wash away service life.

For solving the problems of the technologies described above, the technical solution of the utility model is:

High pulling rate FTSC crystallizer for continuous casting of thin slabs is with four cellular type submersed nozzles, the molten steel inflow end, middle part runner, the bottom outflow end that comprise top are connected successively, the cross section of described middle part runner is more and more flat from the upper entrance to the lower part outlet, more and more wider, described bottom outflow end is provided with the monosymmetric hole that spues, baffle in the middle of being provided with in the described hole that spues, passage spues on bottom outflow end formation four tunnels, spue between hole and be provided with shunting body, the angle of heel α in the described hole that spues is that 25～26 °, high h are that 110～112mm, wide d are 34～35mm; The channelization angle β of described shunting body is that 13～14 °, upper wide c1 are that 36～38mm, lower wide c2 are that 58～60mm, high h1 are that 40～42mm, shunting body end face are provided with arc-shaped recess, and the depression radius R is 15～16mm.

In the middle of described, baffle is crooked, and on it, channelization angle γ is that 15～16 °, lower channelization angle δ are that 34～35 °, width c3 are that 17～19mm, length c4 are 86～87mm; In the middle of two, the relative mouth of a river of baffle central axis is symmetrical, and the upper end spacing c5 of two middle baffles is that 106～108mm, lower end spacing c6 are 156～158mm, and lower end is 61～63mm far from bottom, mouth of a river distance h 2.

The cross section of described middle part runner is continuous transition from the upper entrance to the lower part outlet, the entrance section of middle part runner is tubular, and inner diameter d 1 is 78～80mm, and outer diameter D 1 is 130～132mm; The control cross section one of middle part runner is oblate tubular, and internal diameter major axis b2 is 187～188mm, and internal diameter minor axis d2 is 41～42mm, and external diameter major axis B2 is 250～252mm, and external diameter minor axis D2 is 102～103mm; The control cross section two of middle part runner is oblate tubular, and internal diameter major axis b3 is 227～228mm, and internal diameter minor axis d3 is 37～38mm, and external diameter major axis B3 is 287～289mm, and external diameter minor axis D3 is 95～97mm; Oblate tubular for two muscle of the control cross section three of middle part runner, internal diameter major axis b4 is 293～295mm, and internal diameter minor axis d4 is 34～35mm, and external diameter major axis B4 is 318～320mm, and external diameter minor axis D4 is 78～80mm; Entrance section is 410～412mm apart from the distance of controlling cross section one, and controlling cross section one is 98～100mm apart from the distance of controlling cross section two, and controlling cross section two is 130～132mm apart from the distance of controlling cross section three.

Compared with prior art, the beneficial effects of the utility model are:

1) this mouth of a river adapts to the FTSC thin-slab caster in the high pulling rate condition of production of 5.0～6.0m/min, the mouth of a river has and is no more than ± the steel liquid fluctuating amplitude of 3mm in immersion depth 130～200mm working range, can effectively avoid in crystallizer occurring molten steel face slag phenomenon;

2) the bottom flattened type structure in optimal design appropriate openings degree and substantially downward four holes that spue of direction has been adopted at this mouth of a river, at casting speed 5.0～6.0m/min and when immersing in 130～200mm degree of depth working range continuous casting and producing, it is more even that Mold solidifies the initial solidification shell surrounding thickness of formation, and then guarantee the surface quality of sheet billet;

3) molten steel internal channel and the shunting body of special construction and the outflow end of middle baffle of optimal design have again been adopted in this mouth of a river, the molten steel effluxvelocity that flows out from the working end discharge opening while making its work reduces, the center of vorticity location comparison in the convolution district of two symmetries that form below the discharge opening of its four paths is high, and the protected slag of floating that is conducive to non-metallic inclusions in molten steel absorbs to be removed;

4) baffle in the middle of this mouth of a river is provided with in outflow end, the material structure intensity and the opposing high-temperature molten steel that improve submersed nozzle bottom outflow end wash away service life.

Description of drawings

Fig. 1 is the utility model example structure schematic diagram;

Fig. 2 is the upward view of Fig. 1;

Fig. 3 is along D-D line cutaway view in Fig. 1;

Fig. 4 is along E-E line cutaway view in Fig. 1;

Fig. 5 is along F-F line cutaway view in Fig. 1;

Fig. 6 is along G-G line cutaway view in Fig. 1;

Fig. 7 is the prior art mouth of a river one;

Fig. 8 is the prior art mouth of a river two.

In figure: the 1-molten steel flows into the end 2-middle part runner 3-bottom outflow end 4-baffle 7-hole 8-hole that spues that upwards spues that spues in the middle of the 5-shunting body 6-of hole downwards

The specific embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present utility model is described further:

see Fig. 1, Fig. 2, the high pulling rate FTSC of the utility model crystallizer for continuous casting of thin slabs with four cellular type submersed nozzle example structure schematic diagrames, comprise that top circular tube shaped molten steel flows into end 1, middle part runner 2, bottom outflow end 3 is connected successively, the cross section of middle part runner 2 is more and more flat from the upper entrance to the lower part outlet, more and more wider, bottom outflow end 3 is provided with the monosymmetric hole 4 that spues, spue between hole and be provided with shunting body 5, spue in hole 4 be provided with in the middle of baffle 6, be divided into the four tunnels passage that spues at bottom outflow end 3, most four pore structures that adopt of present FTSC crystallizer for continuous casting of thin slabs have been changed, make the utility model can form more rational flow field of molten steel and temperature field take the main convolution stream of two symmetries as feature in the FTSC crystallizer for continuous casting of thin slabs.

Overall structure and size through the design of hydraulic model and computer simulation analysis optimization are as follows: the hole 4 angle of heel α that spue are that 25～26 °, high h are that 110～112mm, wide d are 34～35mm; Shunting body 5 channelization angle β are that 13～14 °, upper wide c1 are that 36～38mm, lower wide c2 are that 58～60mm, high h1 are that 40～42mm, shunting body end face are provided with arc-shaped recess, the depression radius R is 15～16mm, and the effect of shunting body is shunting and slows down molten steel flow velocity in discharge opening.

Middle baffle 6 is curved shapes, and on it, channelization angle γ is that 15～16 °, lower channelization angle δ are that 34～35 °, width c3 are that 17～19mm, length c4 are 86～87mm; In the middle of two, baffle 6 relative mouth of a river central axis are symmetrical, its upper end spacing c5 is that 106～108mm, lower end spacing c6 are 156～158mm, lower end is 61～63mm far from bottom, mouth of a river distance h 2, middle baffle is that effect is to form the four tunnels passage that spues at the bottom outflow end, and further disperses and reduce the molten steel rate of outflow.

See Fig. 3 to Fig. 6, the cross section of middle part runner 2 is continuous transition from the upper entrance to the lower part outlet, and the entrance section of middle part runner (D-D section) is tubular, and inner diameter d 1 is 78～80mm, and outer diameter D 1 is 130～132mm;

The control cross section one (E-E section) of middle part runner is oblate tubular, and internal diameter major axis b2 is 187～188mm, and internal diameter minor axis d2 is 41～42mm, and external diameter major axis B2 is 250～252mm, and external diameter minor axis D2 is 102～103mm;

The control cross section two (F-F section) of middle part runner is oblate tubular, and internal diameter major axis b3 is 227～228mm, and internal diameter minor axis d3 is 37～38mm, and external diameter major axis B3 is 287～289mm, and external diameter minor axis D3 is 95～97mm;

Oblate tubular for two muscle of the control cross section three (G-G section) of middle part runner, internal diameter major axis b4 is 293～295mm, and internal diameter minor axis d4 is 34～35mm, and external diameter major axis B4 is 318～320mm, and external diameter minor axis D4 is 78～80mm;

Entrance section (D-D section) is 410～412mm apart from the distance of controlling cross section one (E-E section), controlling cross section one (E-E section) is 98～100mm apart from the distance of controlling cross section two (F-F section), and controlling cross section two (F-F section) is 130～132mm apart from the distance of controlling cross section three (G-G section).

Claims

1. high pulling rate FTSC crystallizer for continuous casting of thin slabs is with four cellular type submersed nozzles, the molten steel that comprises top flows into end, the middle part runner, the bottom outflow end is connected successively, the cross section of described middle part runner is more and more flat from the upper entrance to the lower part outlet, more and more wider, described bottom outflow end is provided with the monosymmetric hole that spues, baffle in the middle of being provided with in the described hole that spues, passage spues on bottom outflow end formation four tunnels, spue between hole and be provided with shunting body, it is characterized in that, the angle of heel α in the described hole that spues is 25～26 °, high h is 110～112mm, wide d is 34～35mm, the channelization angle β of described shunting body is that 13～14 °, upper wide c1 are that 36～38mm, lower wide c2 are that 58～60mm, high h1 are that 40～42mm, shunting body end face are provided with arc-shaped recess, and the depression radius R is 15～16mm.

2. high pulling rate FTSC crystallizer for continuous casting of thin slabs according to claim 1 is with four cellular type submersed nozzles, it is characterized in that, in the middle of described, baffle is crooked, and on it, channelization angle γ is that 15～16 °, lower channelization angle δ are that 34～35 °, width c3 are that 17～19mm, length c4 are 86～87mm; In the middle of two, the relative mouth of a river of baffle central axis is symmetrical, and the upper end spacing c5 of two middle baffles is that 106～108mm, lower end spacing c6 are 156～158mm, and lower end is 61～63mm far from bottom, mouth of a river distance h 2.

3. high pulling rate FTSC crystallizer for continuous casting of thin slabs according to claim 1 and 2 is with four cellular type submersed nozzles, it is characterized in that, the cross section of described middle part runner is continuous transition from the upper entrance to the lower part outlet, the entrance section of middle part runner is tubular, inner diameter d 1 is 78～80mm, and outer diameter D 1 is 130～132mm; The control cross section one of middle part runner is oblate tubular, and internal diameter major axis b2 is 187～188mm, and internal diameter minor axis d2 is 41～42mm, and external diameter major axis B2 is 250～252mm, and external diameter minor axis D2 is 102～103mm; The control cross section two of middle part runner is oblate tubular, and internal diameter major axis b3 is 227～228mm, and internal diameter minor axis d3 is 37～38mm, and external diameter major axis B3 is 287～289mm, and external diameter minor axis D3 is 95～97mm; Oblate tubular for two muscle of the control cross section three of middle part runner, internal diameter major axis b4 is 293～295mm, and internal diameter minor axis d4 is 34～35mm, and external diameter major axis B4 is 318～320mm, and external diameter minor axis D4 is 78～80mm; Entrance section is 410～412mm apart from the distance of controlling cross section one, and controlling cross section one is 98～100mm apart from the distance of controlling cross section two, and controlling cross section two is 130～132mm apart from the distance of controlling cross section three.