CN100398229C - Immersion nozzle for continuous casting and continuous casting method using the immersion nozzle - Google Patents
Immersion nozzle for continuous casting and continuous casting method using the immersion nozzle Download PDFInfo
- Publication number
- CN100398229C CN100398229C CNB2004800408477A CN200480040847A CN100398229C CN 100398229 C CN100398229 C CN 100398229C CN B2004800408477 A CNB2004800408477 A CN B2004800408477A CN 200480040847 A CN200480040847 A CN 200480040847A CN 100398229 C CN100398229 C CN 100398229C
- Authority
- CN
- China
- Prior art keywords
- plug hole
- shape
- pouring nozzle
- section
- continuous casting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/50—Pouring-nozzles
Abstract
Immersion nozzles for continuous casting enabling an improvement in the quality of a casting piece surface layer part and an increase in the efficiency of casting by suppressing the self-excited oscillation of a fluid in a mold without using a complicated mechanism such as a swirl flow imparting immersion nozzle. A first immersion nozzle for continuous casting is characterized by comprising a cylindrical body and a pair of discharge holes formed, oppositely to each other, in the side walls near the bottom part of the cylinder body and in that one ridge-shaped projection extending parallel with the discharge direction projected on the cross section of the nozzle is formed on the inner surface of the bottom part and the bottom part is formed in a waterfall basin-like recessed shape having the maximum depth of 5 to 50 mm. A second immersion nozzle for continuous casting is characterized by comprising a cylindrical body and a pair of discharge holes formed, oppositely to each other, in the side walls near the bottom part of the cylindrical body and in that the cross sectional areas of the discharge holes vertical to the discharge direction projected on the cross section or longitudinal section of the nozzle are decreased toward the outlet thereof.
Description
Technical field
The present invention relates to a kind of immersion nozzle of the continuous casting that is used for motlten metals such as molten steel and the continuous casing that uses this pouring nozzle.
Background technology
At the immersion nozzle that uses to have the plug hole of opposite face setting, in as the casting mold of broads such as continuous-casting of steel billet in the continuous casting of supplying melting metal, flowing in the casting mold with certain periodic relief fluctuation, promptly, can produce self-excited vibration, the flow velocity change or the liquid level wave inception of motlten metal in the casting mold takes place easily.Its result can produce by the abnormal quality of sneaking into the casting sheet skin section that the non-metallic inclusion that solidifies the top layer in the casting mold, bubble, casting powder etc. cause.These problems, more remarkable under the bigger situation of the flow velocity of plug hole cast at the such motlten metal of image height speed casting, therefore, have to reduce casting speed.
In the past, to control mobile in such casting mold is purpose, proposed that the method for electromagnetic braking that for example patent documentation 1 disclosed use produces by electromagnetic force or electromagnetic agitation and patent documentation 2 are disclosed to be provided with rotating vane and to give the immersion nozzle of the stream that circles round in pouring nozzle, or the immersion nozzle of the pool shape calixconcavity degree of depth of the increasing of being put down in writing as patent documentation 3 bottom, or the immersion nozzle of putting down in writing as patent documentation 4 that end difference is set in pouring nozzle etc.
But, the method for use electromagnetic force, under many circumstances, equipment cost is higher, can not get and invest corresponding interests.In addition, owing to be difficult to detect motlten metal stream as the control object, so, be under the situation of the state of indeterminate control object, to control under many circumstances, be difficult to bring into play technically effect of sufficient.On the other hand, giving the technology of immersion nozzle of the stream that circles round, as the source and course countermeasure that can make the mobile stabilisation in the casting mold, being identified is otherwise effective technique comparatively.But, when casting contains the lower motlten metal of the cleannes of more non-metallic inclusion, adhere to non-metallic inclusion on the rotating vane in being arranged at pouring nozzle easily, so, the problem that can not cast a large amount of motlten metals continuously had.In addition, the pouring nozzle of end difference is set in pouring nozzle and strengthens the immersion nozzle of the pool shape calixconcavity degree of depth of bottom, though can make in the immersion nozzle and even the mobile stabilisation in the casting mold, because of its effect less, so, not have the leeway of further improveing.
Disclose a kind of immersion nozzle in patent documentation 5, it is by the molten steel delay portion in immersion nozzle endoporus bottom tapered protrusion or flat-top tapered protrusion to be set, and produces the turbulent flow of steel flow in molten steel delay portion, thereby attachment can not be piled up.
Open in the flat 6-218508 communique in the disclosed immersion nozzle this spy, the tapered protrusion of molten steel delay portion or flat-top tapered protrusion, have conical or the such axisymmetric shape in center of polygon taper, by forming such shape, though can prevent to pile up attachment in molten steel delay portion, but it is, also not mentioned in this communique for the mobile stabilisation in the casting mold.
Patent documentation 1: international publication number WO99/15291
Patent documentation 2: the spy opens the 2002-239690 communique
Patent documentation 3: No. 3027645 communique of patent (spy opens flat 5-169212 communique)
Patent documentation 4: No. 3207793 communique of patent (spy opens flat 11-123509 communique)
Patent documentation 5: the spy opens flat 6-218508 communique
Summary of the invention
The object of the present invention is to provide a kind of continuous casting immersion nozzle, it does not use the complex mechanism as the immersion nozzle of giving the stream that circles round, just can suppress the self-excited vibration of flowing in the casting mold, can improve the quality of casting sheet skin section and can carry out the high efficiency casting of long-time continuous.
The present inventor in order to achieve the above object, for studying by the shape of the plug hole periphery of immersion nozzle being carried out the situation about flowing that optimization controls in the casting mold, the result has found the structure with its effect.
The first continuous casting immersion nozzle of the present invention, it is pouring nozzle with main body cylindraceous and a pair of plug hole that opposite face is provided with near the sidewall its bottom, it is characterized in that: on the inner face of bottom, have along the ridge shape projection that the cast direction of projection extends in parallel on the pouring nozzle cross section, described bottom is that depth capacity is the following pool shape calixconcavity shape of the above 50mm of 5mm.
In addition, immersion nozzle is used in second continuous casting of the present invention, and it is characterized in that: the sectional area of the plug hole vertical with respect to the cast direction of projection on pouring nozzle cross section or vertical section reduces towards outlet.
By continuous casing provided by the invention, be to use the continuous casing of continuous casting of the present invention with immersion nozzle; Cast as condition below the above 2.5m/s of 1.0m/s with the flow velocity U that on average descends of the motlten metal on the main body directly over the plug hole.
(invention effect)
According to continuous casting immersion nozzle of the present invention, even do not use the complex mechanism as the immersion nozzle of giving the stream that circles round, also can be from immersion nozzle casting molten metal stably, so can suppress the self-excited vibration of flowing in the casting mold, its result can improve and carries out through the high efficiency casting of long-time continuous casting sheet skin section quality.Continuous casting of the present invention is particularly useful for continuous-casting of steel billet with immersion nozzle and the continuous casing that uses this pouring nozzle, can produce the few steel billet casting sheet of surface blemish and internal flaw.
Description of drawings
Figure 1A is two concept maps that have the eddy current of rotating shaft in the cast direction of expression from the plug hole top view; Figure 1B is having in two eddy current of rotating shaft on the cast direction in the profile on the direction that plug hole is vertically cut open, the concept map of the eddy current of side in front of the expression;
Fig. 2 is continuous casting of the present invention with the outside drawing of observing from plug hole next door side of immersion nozzle the state of plug hole (about observe);
Fig. 3 is the outside drawing from plug hole face side observation of continuous casting of the present invention with immersion nozzle;
Fig. 4 A is that first continuous casting of the present invention is with the drawing in side sectional elevation on the height that is higher than plug hole of immersion nozzle; Fig. 4 B is the A-A profile (being the profile on the direction of cross-sectional ridge shape projection) among Fig. 4 A; Fig. 4 C is the B-B profile (being the profile on the direction of vertical profile plug hole) among Fig. 4 A;
Fig. 5 A～Fig. 5 J is for being arranged on the various examples of continuous casting of the present invention with the ridge shape projection on the inner face of immersion nozzle bottom, the profile of ridge shape projection on two plug hole directions of vertical profile and pouring nozzle bottom;
Fig. 6 is the example of continuous casting of the present invention with the plug hole of immersion nozzle, the profile on the direction of vertical profile plug hole;
Fig. 7 is the example of continuous casting of the present invention with the plug hole of immersion nozzle, the profile on the direction of vertical profile plug hole;
Fig. 8 is the example of continuous casting of the present invention with the plug hole of immersion nozzle, the profile on the direction of vertical profile plug hole;
Fig. 9 is the profile that the immersion nozzle structure is used in the continuous casting among the expression embodiment 3;
Figure 10 is the profile that the immersion nozzle structure is used in the continuous casting among the expression embodiment 5;
Figure 11 is the profile that the immersion nozzle structure is used in the continuous casting in the expression comparative example 7.
The represented meaning of symbol among each figure is as described below: 1-pouring nozzle main body, 2-pouring nozzle bottom, 3-pouring nozzle sidewall, 3 '-the pouring nozzle inwall, 4a, 4b-plug hole, 4in-plug hole inlet, the outlet of 4out-plug hole, 5-ridge shape projection, 6a, 6b-plug hole upper wall, 7a, 7b-plug hole lower wall.
The specific embodiment
The present inventor, for immersion nozzle with cylindrical body and a pair of plug hole that opposite face is provided with near the sidewall its bottom, shape to the plug hole periphery has been carried out various changes, and carried out full scale water model repeatedly (full scale water modle) and tested, found that flowing of in immersion nozzle, descending, with the collision of pouring nozzle bottom, shown in Figure 1A and Figure 1B, have two eddy current of rotating shaft and the situation of cast according at this moment forming along the cast direction, the change conditions of the size of the whirlpool that forms in this bottom, in addition, according to the change conditions of bottom formation whirlpool size, form sometimes and have only the wherein state of a side whirlpool existence.And, find to form the change of the size of whirlpool in this bottom, make from the immersion nozzle cast water the beam disorder, thereby make the interior flowing instability of casting mold.
And, the present inventor is found that of making further research, be arranged on the inner face of pouring nozzle bottom by 1 ridge shape projection that will extend in parallel with cast direction in projection on the pouring nozzle cross section, can be changed to when having the eddy current of rotating shaft at the sinking that arrives the bottom along the cast direction, make towards relative stable eddy current to two plug holes that are provided with, be respectively formed in two zones that separate by above-mentioned ridge shape projection, stablize thereby make to flow.
In addition, learn that the self-excited vibration in order to suppress to flow in the casting mold forms the pool shape calixconcavity shape of depth capacity below the above 50mm of 5mm, the effect that can obtain with the bottom inner face.Here, so-called pool shape calixconcavity shape is meant, by than plug hole lower wall by under the calixconcavity shape that surrounds of downside inwall.By the immersion nozzle bottom is formed pool shape calixconcavity shape, during sinking distributions shift that can be in pouring nozzle, by pool shape calixconcavity shape the sinking in the pouring nozzle is upspring, its result, formed counter-rotating stream has the effect that the opposite side of sinking in pouring nozzle is distributed molten steel, therefore, be considered to water by adjustment the distribution of beam, the result can stablize and waters beam.
As a kind of conventional art, open the immersion nozzle of being put down in writing in the flat 6-218508 communique above-mentioned spy, in the molten steel delay portion of immersion nozzle endoporus bottom, have tapered protrusion or flat-top tapered protrusion.Tapered protrusion of being put down in writing in this communique or flat-top tapered protrusion have the axisymmetric shape in center as conical or polygon taper, and in other words, the axle that has with immersion nozzle is the center, all impartial shape on 360 orientation of spending arbitrarily.
And the ridge shape projection that is present in pouring nozzle bottom inner face of the present invention has the shape of the thinner thickness that extends along the direction parallel with the pouring molten steel direction essence of projection on the pouring nozzle cross section, in other words, has on the cast direction and is elongated shape.Therefore, the present invention opens the invention of being put down in writing in the flat 6-218508 communique with the spy and compares, and the basic configuration of projection is different.
And on the effect that convex shape had, the present invention opens the invention of being put down in writing in the flat 6-218508 communique and has bigger different with special.Open in the invention of being put down in writing in the flat 6-218508 communique the spy, disperse equably at the periphery molten steel of projection, and in the molten steel delay portion of bottom, steel flow is stirred and forms turbulent flow, can suppress the accumulation of attachment.But taper in the invention of being put down in writing in this communique or flat-top tapered protrusion be not in the peripheral effect that forms the eddy current of stable MOLTEN STEEL FLOW of plug hole.
And in the present invention, from the top view of plug hole, in the left and right sides of ridge shape projection, the stable respectively eddy current that has the steel flow of rotating shaft along the cast direction that forms thus, makes the MOLTEN STEEL FLOW stabilisation of watering in beam and the casting mold.
Immersion nozzle is used in first continuous casting of the present invention, is based on above-mentioned opinion and the technical scheme that proposes.Fig. 2 to Fig. 4 has shown an example that constitutes the first continuous casting usefulness immersion nozzle of the present invention.In addition, Fig. 2 is continuous casting of the present invention with the outside drawing of observing from plug hole next door side of immersion nozzle the state of plug hole (about observe); Fig. 3 is the outside drawing of observing from the plug hole face side; In addition, Fig. 4 A is that first continuous casting of the present invention is with the drawing in side sectional elevation on the height that is higher than plug hole of immersion nozzle; Fig. 4 B is the A-A profile (being the profile on the direction of cross-sectional ridge shape projection) among Fig. 4 A; Fig. 4 C is the B-B profile (being the profile on the direction of vertical profile plug hole) among Fig. 4 A.
Below, the present invention will be described with reference to Fig. 4.First immersion nozzle of the present invention, a pair of plug hole 4a, 4b with main body 1 cylindraceous and opposite face setting near the sidewall 3 its bottom 2, be provided with on the bottom inner face 2 with cross section at pouring nozzle on 1 ridge shape projection 5 extending in parallel of the cast direction of projection, and the inner face of bottom 2 is formed depth capacity H is pool shape calixconcavity shape below the above 50mm of 5mm.
By pool shape calixconcavity shape being formed its depth capacity H below the above 50mm of 5mm, the effect that can obtain.Here, so-called depth capacity H is meant the distance of putting to the deep-seated of pool shape calixconcavity from the intersection location of plug hole lower wall and pouring nozzle main body inner wall.If depth capacity H is not enough 5mm, then can not get being provided with the effect of pool shape calixconcavity shape.On the other hand,, then can adhere to the accumulation non-metallic inclusion at shape calixconcavity place, pool if depth capacity H has surpassed 50mm, and, also can be not easy to operation because of immersion nozzle is long.For the depth capacity H of pool shape calixconcavity shape, preferably below the above 30mm of 10mm.As the shape of pool shape calixconcavity, make horizontally or skewed etc. even will not form the part of ridge shape projection 5, perhaps be that to form calixconcavity on sphere also no problem.
(for example this crest line can be made as arrival than the low position of the plug hole of the sidewall of pool shape calixconcavity part, Fig. 5 A～Fig. 5 D), perhaps can be made as and near the plug hole in pouring nozzle cross section, arrive the bottom, ridge shape projection 5 itself (for example disappears, Fig. 5 E～Fig. 5 G), perhaps can be made as near the pouring nozzle central part and to arrive the bottom, only ridge shape projection 5 is located at (for example, Fig. 5 H～Fig. 5 J) near the central part in pouring nozzle cross section.In ridge shape projection 5 in disappearing near the plug hole in pouring nozzle cross section or only being arranged under near the central part in pouring nozzle cross section the situation, also comprise this crest line vertically descending midway from the top of level or towards the plug hole step-down, arrive the situation (for example, Fig. 5 G, Fig. 5 J) of pouring nozzle bottom.Here, be roughly at internal diameter under the situation of general immersion nozzle of 80～90mm, near the plug hole in so-called pouring nozzle cross section, it is plug hole on the span pouring nozzle cross section roughly scope of 15mm that enters the mouth, near the central part in so-called pouring nozzle cross section, be the center scope of 20mm roughly in span pouring nozzle cross section
The present inventor is from carrying out found that of above-mentioned water model test repeatedly, when ridge shape projection 5 is excessive, can present the situation similar flow regime more shallow to pool shape calixconcavity, can not give full play of the effect that is produced by pool shape calixconcavity shape.At this, the present inventor has done further research, and discovery is for balance and give full play to above-mentioned pool shape calixconcavity shape and the effect of ridge shape projection 5, preferably makes ridge shape projection 5 have following shape.
That is, the preferable shape of ridge shape projection 5 is meant that it is highly for the highest near the central part in pouring nozzle cross section or its, and near the plug hole inlet in pouring nozzle cross section, it highly is lower shape.Because near the central part in pouring nozzle cross section or its, the flow velocity of the sinking in pouring nozzle is bigger, so, as mentioned above, near the central part in pouring nozzle cross section or its, by it being set, can more effective and stably form the bottom formation whirlpool that the sinking that makes in the pouring nozzle forms with the collision of pouring nozzle bottom highly for the highest ridge shape projection.In addition, near plug hole inlet, the ridge shape projection that it is highly lower makes the bottom form whirlpool and enters the bottom of pool shape calixconcavity easily, and can further strengthen the effect of upspringing of sinking in the pouring nozzle that the shape by pool shape calixconcavity produces.
In the preferable shape of above-mentioned ridge shape projection 5, pouring nozzle cross section central part or near the highest part it can be the summits, also can be the tops.In addition, so-called " its height is lower near the plug hole inlet ", comprise following situation, promptly, the crest line of ridge shape projection 5 from the summit of ridge shape projection 5 or the top towards two plug hole step-downs and arrive the situation of the position lower than the plug hole lower wall of the sidewall of pool shape calixconcavity part, near the situation that ridge shape projection 5 self disappears the plug hole in pouring nozzle cross section inlet perhaps is arranged near the situation central part of pouring nozzle cross section etc. with protruding 5 of ridge shape.
Particularly, preferable shape as ridge shape projection 5, can exemplify out such structure, that is, at first, at center, pouring nozzle cross section or near the top that has summit or level it, its crest line from the top of described summit or level towards two plug holes and step-down, and arrival particularly, comprises the situation shown in Fig. 5 B, Fig. 5 C, Fig. 5 D than the low position of plug hole lower wall of the sidewall of pool shape calixconcavity part.In addition, can also exemplify out such structure, promptly, near center, pouring nozzle cross section or its, top with summit or level, towards two plug holes and step-down, and projection self disappearance during near the bottom arriving the plug hole inlet in pouring nozzle cross section comprises the situation shown in 5E, Fig. 5 F, Fig. 5 G to its crest line particularly from the top of described summit or level.And, can also exemplify out such structure, promptly, near pouring nozzle cross section central part or its, top with summit or level, its crest line, only is arranged on this ridge shape projection near the central part of pouring nozzle cross section towards two plug holes and step-down or vertically descend and arrive the bottom from the top of described level, comprises the situation shown in 5H, Fig. 5 J particularly.
About the thickness (cross section of ridge shape projection 5) of ridge shape projection 5, if protruding top is too thin, then projection lacks durability, if blocked up, then the formation to whirlpool has bad influence, therefore, preferably protruding top is made as about 5mm～15mm.About protruding bottom, can have the thickness identical with top, also can be to increase the shape of thickness along with mode to the preceding of bottom and then expansion.
By ridge shape projection is set, forms sometimes and be similar to flowing of the more shallow state of pool shape calixconcavity, and can not get the sufficient effect that produces by pool shape calixconcavity.The present inventor uses in the immersion nozzle in first continuous casting of the present invention, found form in that the shape of the pool shape calixconcavity of bottom is enlarged along the cast direction of projection on the pouring nozzle cross section than pouring nozzle inner major diameter big oval or oval in, can address the above problem and strengthen the structure of cloth pool shape calixconcavity effect.Whirlpool is formed on the stable bottom that is convexed to form by the ridge shape, can strengthen the whirlpool of cast direction as rotating shaft, forms along high the flowing of cast direction rectilinear propagation.Can think such mobile higher fluid flow state of viscosity that is similar to, because be difficult to enter the bottom of little calixconcavity, so, upspring after entering pool shape calixconcavity in order to make fluid, just must strengthen the area of pool shape calixconcavity, and make fluid enter the bottom of pool shape calixconcavity easily.Therefore, infer convexing to form by the ridge shape in the immersion nozzle of the present invention of stable strong whirlpool, pool shape calixconcavity is formed the oval or oval shape bigger than above-mentioned pouring nozzle inner major diameter, can further improve the effect of pool shape calixconcavity.In addition, the effect of such pool shape calixconcavity also can be by the pouring nozzle inner major diameter itself being formed the oval or oval shape that enlarges along the cast direction.
In addition, the present inventor finds, waters the beam stabilisation in order to make, except the effect of above-mentioned ridge shape projection and pool shape calixconcavity, do not make water beam from the sidewall of plug hole or go up lower wall peel off pour into a mould (separation) also very important.This be because, water beam from wall or separation or the change itself of adhering to, make the essential factor of flowing instability exactly, and the continuous casting immersion nozzle is because such turbulent flow, promoted to make non-metallic inclusion the adhering to that is included in the motlten metal to plug hole, along with the carrying out of casting, the plug hole shape can change, and produces to make to water the unsettled phenomenon of beam.
The second continuous casting immersion nozzle of the present invention, the technical scheme that is based on above-mentioned opinion and proposes, it is characterized in that, this pouring nozzle has a pair of plug hole of main body cylindraceous and opposite face setting near the sidewall its bottom, the area of the plug hole section vertical with respect to the cast direction of projection on the cross section of pouring nozzle or vertical section reduces to outlet from inlet.
Second continuous casting of the present invention is shown in Fig. 6 to Fig. 8 with the structure example of immersion nozzle.In addition, Fig. 6 to Fig. 8 is the profile on the direction that second continuous casting of the present invention is vertically cut open with the plug hole of immersion nozzle.
Below, the present invention will be described with reference to Fig. 6.Second immersion nozzle of the present invention, a pair of plug hole 4a, 4b with main body 1 cylindraceous and opposite face setting near the sidewall 3 its bottom 2, the area of the plug hole section vertical with respect to the cast direction of projection on pouring nozzle cross section or vertical section is the shape that reduces to outlet 4out from plug hole inlet 4in.
By making the area of the plug hole section vertical with respect to the cast direction of projection on pouring nozzle cross section or vertical section, 4in reduces to outlet 4out from the plug hole inlet, can prevent to water beam peeling off from the cast hole wall, and can make and water the beam stabilisation.And, near plug hole, be not easy to produce the viscous flow of watering beam, so, can suppress to be included in the adhering to plug hole such as non-metallic inclusion in the motlten metal, and prevent the casting sheet defective that causes of peeling off because of the obstruction of plug hole or attachment, even under the situation of long-time casting, also can guarantee the quality of stable operation and casting sheet.
The area of above-mentioned plug hole section can form gradually and narrows down, and also can form near outlet sharply to narrow down, but stably pour into a mould and prevent the viewpoint of adhering to of non-metallic inclusion from watering beam, had better not sharply reduce.In addition, the area of plug hole section can be formed on short transverse and reduce, also can form on width and reduce, in addition, also can form on short transverse and width two directions and reduce.
Sinking in the pouring nozzle changes direction in the pouring nozzle bottom, is produced the velocity of horizontal direction, and flows into plug hole to oblique below.On near the flow behavior this plug hole, be to make to water beam and pour into a mould along the plug hole lower wall.Therefore, if the excessive height of plug hole, then cast fails to be convened for lack of a quorum and peels off from the plug hole upper wall.As preventing that this from watering the countermeasure that beam is peeled off, immersion nozzle is used in second continuous casting of the present invention, preferably has such plug hole,, has width the grow crosswise shape bigger than the height of plug hole of plug hole that is.As the shape of growing crosswise, particularly, the average height of preferred plug hole outlet is more than 0.5 times below 0.9 times of mean breadth of plug hole outlet.If 0.5 times of the mean breadth of plug hole outlet that the average height of plug hole outlet is not enough, then the area of plug hole is not enough, it or not desirable structure, if the average height of plug hole outlet surpasses 0.9 times of mean breadth of plug hole outlet, the effect of the shape that then can not get plug hole and be growing crosswise.As long as the shape of plug hole is the above-mentioned shape of growing crosswise, then can be polygon or the ellipse beyond the square, or have the roughly quadrangle etc. of R in the bight that there is no particular limitation.
And, the second continuous casting immersion nozzle of the present invention, be set in outlet reduces scope as purpose at the area of above-mentioned plug hole section, as Fig. 7 and shown in Figure 8, plug hole upper wall 6a and 6b, be preferably formed and be the circular shape below the above R150mm of radius of curvature R 30mm, that is, and from the inwall 3 of pouring nozzle main body ' the have shape of expander shape section towards the plug hole upper wall; And plug hole lower wall 7a and 7b, its angle from up 15 ° in 45 ° scope down.In addition, Fig. 7 shows is angle 15 ° the situation up of plug hole lower wall 7a and 7b, and Fig. 8 shows is angle 45 ° the situation down of plug hole lower wall 7a and 7b.By the plug hole upper wall is formed such shape, can make near oblique the flowing and pour into a mould down the plug hole along the plug hole upper wall, so, can prevent more effectively that watering beam peels off from the upper wall of plug hole.
When the radius of curvature R of plug hole upper wall less than 30mm the time, reducing of above-mentioned plug hole sectional area is just not enough, and curvature is too urgent, just can not make to water beam and pour into a mould along upper wall, therefore, waters peeling off of beam easily.In addition, as the R of plug hole upper wall the time greater than 150mm, the thickness attenuation of the pouring nozzle of plug hole upper wall and can reduce durability.On the other hand, if the angle of plug hole lower wall makes progress greater than 15 °, then the mobile grow that rises from plug hole can cause liquid level wave inception in the casting mold.In addition, if the angle of plug hole lower wall is downwards greater than 45 °, then cast fails to be convened for lack of a quorum and enters into the casting mold depths, supplying melting metal to the casting mold liquid level will be not enough, therefore, the heat of supplying with to liquid level is just not enough, thereby causes the liquid level temperature to reduce, and produces the problem that hinders the come-up of removing non-metallic inclusion or bubble.And, make to be difficult to the sectional area of plug hole is reduced towards Way out, therefore can not reach and will prevent to water the initial purpose that beam is peeled off from the cast hole wall.
When continuous casting immersion nozzle of the present invention is when being combined in each structure that first continuous casting of the present invention adopts in casting continuously with immersion nozzle with immersion nozzle and second, can further stablize according to its effect that multiplies each other and to water flowing of beam, and can suppress the self-excited vibration of flowing in the casting mold effectively.
As mentioned above, by using by continuous casting immersion nozzle provided by the present invention, can make from continuous casting with the immersion nozzle cast water the beam stabilisation, therefore, can suppress self-excited vibration mobile in the casting mold.Its result can prevent to catch the non-metallic inclusion that solidifies the top layer, bubble, casting powder etc., reaches the purpose of improving casting sheet skin section quality improvement.In addition, according to the stablizing effect that waters beam, even in the high efficiency casting, particularly, even at the cast flow from immersion nozzle cast is under the situation of the high-throughput about 4.5～7.0t/min, also can be through long-time and form in the stable casting mold and flow.
Use the casting of continuous casting of the present invention with immersion nozzle, even in above-mentioned high efficiency casting, also can form stable cast flows, but when requiring to improve the casting tablet quality more, the preferred average decline flow velocity U of motlten metal in the pouring nozzle on the main body directly over plug hole is in the scope below the above 2.5m/s of 1.0m/s.Here, be meant the inwall 3 ' crossing part of plug hole upper wall 6 and pouring nozzle main body directly over the so-called plug hole.Be set in the above-mentioned scope by flow velocity U that motlten metal in the pouring nozzle is on average descended, especially can obtain the stabilization effect that height waters beam, that is, can obtain the stabilization effect that flows in the casting mold.When motlten metal in the pouring nozzle directly over the plug hole on average descends flow velocity U deficiency 1.0m/s,,, water beam also with regard to instability so the sinking in the pouring nozzle is just unstable, influenced by it with respect to the flow of molten metal minimizing of pouring nozzle internal diameter.Therefore, under the little casting condition of flow of molten metal, by the pouring nozzle internal diameter being provided with to such an extent that lessly guarantee in the pouring nozzle that the motlten metal flow velocity U that on average descends is important more than 1.0m/s.When motlten metal in the pouring nozzle directly over the plug hole on average descends flow velocity U when surpassing 2.5m/s, the decline flow velocity in the pouring nozzle is excessive, thereby makes that the cast flow velocity is excessive, and problems such as melting again of top layer take place to solidify in liquid level wave inception or the casting mold sometimes.
The motlten metal flow velocity U that on average descends in the above-mentioned pouring nozzle can obtain by (the interior motlten metal of pouring nozzle on average descend flow)/(pouring nozzle main body sectional area).Here, the motlten metal flow that on average descends is the value by (casting sheet casting speed) * (casting sheet sectional area) * (casting sheet proportion)/(molten steel proportion) is obtained in the pouring nozzle.
In addition, when motlten metal on average descends flow velocity U in calculating pouring nozzle,, can use the positive upper part diameter of plug hole to calculate when the internal diameter of pouring nozzle main body is when changing pouring nozzle top is directly over plug hole.
(embodiment)
Below, embodiments of the invention and comparative example are compared, effect of the present invention is described.
With employed continuous casting immersion nozzle in embodiment 1～6 and the comparative example 7～9, show in table 1 with main body cylindraceous and a pair of plug hole that opposite face is provided with near the sidewall its bottom.
In addition, the average height and the mean breadth of the plug hole outlet when the plug hole outlet has the R shape in the bight are obtained by following method.That is, the plug hole that will have the R shape in the bight is made as, and two sides of height and width are dwindled identical length, have and this plug hole square that does not have the R shape in the bight of the same area.With the tetragonal height obtained like this and width average height and mean breadth as the plug hole outlet.For example, in the Fig. 9 that shows embodiment 3, be that the height of plug hole outlet is 68mm, width is the roughly square that has R in the bight of 80mm.If consider that the bight is the shape of R10mm, then the mean breadth of the average height of plug hole outlet, plug hole outlet reduces about 1mm simultaneously from the height of plug hole outlet, the width of plug hole outlet respectively.That is, the average height of plug hole outlet is 67mm (rounding up below the decimal point), and the mean breadth of plug hole outlet is 79mm (rounding up below the decimal point).For the algorithm of the mean breadth of the average height of plug hole outlet and plug hole outlet, other embodiment and comparative example also are same.
(evaluation method)
In embodiment shown in the table 1 and comparative example, various changes have been carried out for continuous casting with motlten metal decline flow velocity U in size, shape and the pouring nozzle of the bottom of immersion nozzle and plug hole, by imitation casting mold thickness is that 235～270mm, casting mold width are the bad continuous casting machine full scale of the plate water model test of 1500～2300mm, and the stability that flows in the casting mold is estimated.In the table 1 that the continuous casting of using in each embodiment and comparative example is shown with the structure of immersion nozzle, and show in Fig. 9～Figure 11 aptly.
Here, stability flows in the so-called casting mold, be meant in above-mentioned full scale water model test, flow velocity to the casting mold cross direction among 1/2 thick, the 1/4 wide underwater 50mm in the casting mold, two places respectively measure 15 minutes about the casting mold width, to the value that the standard deviation with determination data removes with its flow velocity mean value, estimate with grade (level) differentiation.In addition, in above-mentioned mensuration, used the propeller type current meter, with 0.5 second measuring space above-mentioned flow velocity.With the instantaneous value data of 0.5 second measuring space because the influence of small whirlpool can cause big change, so, will be data by per value that averaged in 2.5 seconds as least unit, be used for basis of calculation deviation.
Metewand about the stability that flows in the casting mold, when the value less than 0.4 of above-mentioned standard deviation/mean value is " more excellent ", when the value of above-mentioned standard deviation/mean value more than 0.4 but be " excellent " during less than 0.5, when the value of above-mentioned standard deviation/mean value more than 0.5 but be " very " during less than 0.6, when the value of above-mentioned standard deviation/mean value more than 0.6 but during less than 0.7 be " can ", when the value of above-mentioned standard deviation/mean value 0.7 when above be " can not ".The present inventor by rule of thumb as can be known, as long as the stability that flows in the casting mold be " more excellent " to " very ", it is stable then flowing in the casting mold when real machine uses this immersion nozzle, it is little that liquid level wave inception and grade are changed, it is good casting the sheet surface quality.In addition, when the stability that flows in casting mold be " can " or " can not ", even on real machine, it was also unstable easily to flow in the casting mold, can make in the casting mold liquid level wave inception and grade change big, and the trend that makes the deterioration of casting sheet surface quality is arranged.
(evaluation result)
Embodiment 1 has the immersion nozzle of first continuous casting of the present invention with the feature of immersion nozzle, and the shape of its pool shape calixconcavity and ridge shape projection all are formed optimal way.Promptly, the pool shape calixconcavity that on the inner face of pouring nozzle bottom, forms, be to be formed on the cast direction of projection on the horizontal flat cutting face of pouring nozzle bigger oval, profile (side view) on the direction of the plug hole of vertical profile ridge shape projection is, have the base of the length identical and the equilateral triangle of the maximum height identical with the degree of depth of pool shape calixconcavity with described oval major diameter, its crest line is that the position of intersecting with the pouring nozzle sidewall in the pouring nozzle bottom arrives the pouring nozzle bottom surface.Therefore, can make the edge on the pouring nozzle bottom pour into a mould the swirl stabilization formation that direction has rotating shaft.And, in preferred pouring nozzle, under the decline flow conditions,, obtained the stability that flows in the good casting mold owing to used such immersion nozzle.
As shown in figure 11, for pool shape calixconcavity and ridge shape projection not being set simultaneously at pouring nozzle bottom inner face, but with respect in the pouring nozzle cross section or the vertical plug hole sectional area of cast direction that cuts open projection in length and breadth be certain comparative example 7, do not make and water the beam stabilisation.And, because the decline flow velocity is bigger in the pouring nozzle, therefore, the stability that flows in the casting mold be " can not ".
Comparative example 8 is that pouring nozzle bottom inner face is formed the structure of pool shape calixconcavity shape, but ridge shape projection is not set, so, do not have to form fully stable bottom and form whirlpool.In addition, the plug hole upper wall is formed the circular shape of R40mm, and be shape towards described plug hole upper wall with expander shape section from the inwall of main body, and, the plug hole lower wall is formed has the downward 45 ° shape of angle, but in the upper wall of R40mm and downward 45 ° lower wall combination of shapes, the sectional area of above-mentioned plug hole is reduced towards outlet, extended near outlet on the contrary.Therefore, can not make and water the beam stabilisation, the stability that flows in the casting mold be " can not ".
Comparative example 9 is that pouring nozzle bottom inner face is formed the structure of pool shape calixconcavity shape, but ridge shape projection is not set, so, do not have to form fully stable bottom and form whirlpool.In addition, above-mentioned plug hole cross sectional area is certain, does not make and waters the beam stabilisation.And, because the decline flow velocity is less in the pouring nozzle, so, water the beam instability, therefore, the stability that flows in the casting mold be " can not ".
Claims (7)
1. continuous casting immersion nozzle has a pair of plug hole of main body cylindraceous and opposite face setting near the sidewall its bottom, and this pouring nozzle is characterised in that,
On the inner face of bottom, have along the ridge shape projection that the cast direction of projection extends in parallel on the pouring nozzle cross section, described bottom is that depth capacity is the following pool shape calixconcavity shape of the above 50mm of 5mm.
2. continuous casting immersion nozzle according to claim 1 is characterized in that,
Described ridge shape projection, near the central part in pouring nozzle cross section or its, top with summit or level, its crest line from the top of described summit or level towards two plug holes and step-down, and arrival is than the low position of plug hole lower wall of the sidewall of pool shape calixconcavity part, perhaps its crest line from the top of described summit or level towards two plug holes and step-down, and projection self disappearance during near the bottom arriving the plug hole inlet in pouring nozzle cross section, perhaps this ridge shape projection is near pouring nozzle cross section central part or its, top with level, its crest line from the top of described level towards two plug holes and step-down or vertically descend and arrive the bottom, and only be arranged near the central part of pouring nozzle cross section, and, the depth capacity of the maximum height of this ridge shape projection and described pool shape calixconcavity is identical or in the scope of the depth capacity ± 10mm of pool shape calixconcavity, and then the maximum height of this ridge shape projection is below the above 50mm of 5mm.
3. continuous casting immersion nozzle according to claim 1 is characterized in that,
Described pool shape calixconcavity is on the cast direction of projection on the pouring nozzle cross section, than pouring nozzle inner major diameter big ellipse or oblong shape.
4. continuous casting immersion nozzle according to claim 2 is characterized in that,
Described pool shape calixconcavity is on the cast direction of projection on the pouring nozzle cross section, than pouring nozzle inner major diameter big ellipse or oblong shape.
5. continuous casting immersion nozzle according to claim 1 is characterized in that, the sectional area of the plug hole vertical with respect to the cast direction of projection on pouring nozzle cross section or vertical section reduces towards outlet, and,
Plug hole outlet average height is more than 0.5 times below 0.9 times of plug hole outlet mean breadth.
6. continuous casting immersion nozzle according to claim 5 is characterized in that,
The plug hole upper wall is formed radius of curvature circular-arc below the above 150mm of 30mm, and has a shape of the expander shape section that enlarges towards described plug hole upper wall from the inwall of described main body, the angle of plug hole lower wall is making progress 15 ° in downward 45 ° scope.
7. a continuous casing that uses the described continuous casting of claim 1 with immersion nozzle is characterized in that, the motlten metal of the main body flow velocity that on average descends is below the above 2.5m/s of 1.0m/s directly over the described plug hole.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004015340 | 2004-01-23 | ||
| JP015340/2004 | 2004-01-23 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1905966A CN1905966A (en) | 2007-01-31 |
| CN100398229C true CN100398229C (en) | 2008-07-02 |
Family
ID=34805453
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004800408477A Expired - Fee Related CN100398229C (en) | 2004-01-23 | 2004-12-22 | Immersion nozzle for continuous casting and continuous casting method using the immersion nozzle |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US20070158884A1 (en) |
| JP (1) | JP4508110B2 (en) |
| CN (1) | CN100398229C (en) |
| WO (1) | WO2005070589A1 (en) |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4686442B2 (en) * | 2006-12-28 | 2011-05-25 | 株式会社神戸製鋼所 | Split nozzle with immersion weir |
| JP4750013B2 (en) * | 2006-12-28 | 2011-08-17 | 株式会社神戸製鋼所 | Immersion nozzle with drum type weir |
| ITMI20070083A1 (en) * | 2007-01-22 | 2008-07-23 | Danieli Off Mecc | SUBMERGED UNLOADER |
| JP4320043B2 (en) * | 2007-10-30 | 2009-08-26 | 株式会社神戸製鋼所 | Continuous casting method of medium and high carbon steel using submerged dammed nozzle |
| JP5027625B2 (en) * | 2007-11-19 | 2012-09-19 | 株式会社神戸製鋼所 | Immersion nozzle for continuous casting |
| AU2009230356B2 (en) * | 2008-03-27 | 2011-09-15 | Krosaki Harima Corporation | Immersion nozzle for continuous casting |
| JP5047854B2 (en) * | 2008-03-27 | 2012-10-10 | 黒崎播磨株式会社 | Immersion nozzle for continuous casting |
| JP4695701B2 (en) * | 2009-07-24 | 2011-06-08 | 黒崎播磨株式会社 | Molten metal discharge nozzle |
| WO2011055484A1 (en) * | 2009-11-06 | 2011-05-12 | 住友金属工業株式会社 | Continuous casting method for molten metal |
| JP5347922B2 (en) * | 2009-11-30 | 2013-11-20 | 新日鐵住金株式会社 | Immersion nozzle for continuous casting and continuous casting method |
| JP4665056B1 (en) * | 2010-03-31 | 2011-04-06 | 黒崎播磨株式会社 | Immersion nozzle |
| US9676029B2 (en) | 2010-07-02 | 2017-06-13 | Vesuvius Crucible Company | Submerged entry nozzle |
| CA2800388C (en) * | 2010-07-02 | 2019-12-03 | Vesuvius Crucible Company | Submerged entry nozzle |
| JP5701004B2 (en) * | 2010-10-13 | 2015-04-15 | 三菱重工業株式会社 | Die casting mold |
| JP2012183544A (en) * | 2011-03-03 | 2012-09-27 | Kurosaki Harima Corp | Immersion nozzle |
| JP5645736B2 (en) | 2011-03-31 | 2014-12-24 | 黒崎播磨株式会社 | Immersion nozzle for continuous casting |
| CN110125379A (en) * | 2019-04-24 | 2019-08-16 | 首钢集团有限公司 | A kind of submersed nozzle reducing nozzle blocking |
| JP7121299B2 (en) * | 2019-12-27 | 2022-08-18 | 品川リフラクトリーズ株式会社 | immersion nozzle |
| JP7175513B2 (en) * | 2020-02-12 | 2022-11-21 | 明智セラミックス株式会社 | immersion nozzle |
| CN117463986B (en) * | 2023-12-22 | 2024-04-05 | 北京科技大学 | Method for improving castability of ultra-thick high-carbon steel |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4819840A (en) * | 1986-07-12 | 1989-04-11 | Thyssen Stahl Aktiengesellschaft | Refractory submerged pouring nozzle |
| JPH06218508A (en) * | 1993-01-28 | 1994-08-09 | Toshiba Ceramics Co Ltd | Dipping nozzle for continuous casting |
| JPH09285852A (en) * | 1996-04-23 | 1997-11-04 | Nippon Steel Corp | Continuous casting method, and immersion nozzle for continuous casting |
| CN1271303A (en) * | 1997-09-22 | 2000-10-25 | 丸川雄净 | Immersion nozzle |
| JP2001321901A (en) * | 2000-05-15 | 2001-11-20 | Sumitomo Metal Ind Ltd | Method for continuously casting steel |
| JP2003025048A (en) * | 2001-05-11 | 2003-01-28 | Nippon Steel Corp | Method for continuously casting steel |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS626957U (en) * | 1985-06-28 | 1987-01-16 | ||
| JPH0120052Y2 (en) * | 1985-07-08 | 1989-06-12 | ||
| JPH0439547U (en) * | 1990-07-30 | 1992-04-03 | ||
| US5227078A (en) * | 1992-05-20 | 1993-07-13 | Reynolds Metals Company | Flow-vectored downspout assembly and method for using same |
| JPH09295108A (en) * | 1996-04-25 | 1997-11-18 | Dowa Mining Co Ltd | Casting method using float for casting and its device |
| US5954989A (en) * | 1997-03-20 | 1999-09-21 | Vesuvius Crucible Company | Erosion and abrasion resistant refractory composition and article made therefrom |
| US6016941A (en) * | 1998-04-14 | 2000-01-25 | Ltv Steel Company, Inc. | Submerged entry nozzle |
| JP3548112B2 (en) * | 2000-10-26 | 2004-07-28 | 明智セラミックス株式会社 | Immersion nozzle for continuous casting |
| JP2003311381A (en) * | 2002-04-19 | 2003-11-05 | Nippon Steel Corp | Immersion nozzle for continuous casting, restraining development of surface defect and internal defect and continuous casting method using this nozzle for continuous casting |
-
2004
- 2004-12-22 JP JP2005517208A patent/JP4508110B2/en active Active
- 2004-12-22 CN CNB2004800408477A patent/CN100398229C/en not_active Expired - Fee Related
- 2004-12-22 WO PCT/JP2004/019260 patent/WO2005070589A1/en active Application Filing
- 2004-12-22 US US10/586,346 patent/US20070158884A1/en not_active Abandoned
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4819840A (en) * | 1986-07-12 | 1989-04-11 | Thyssen Stahl Aktiengesellschaft | Refractory submerged pouring nozzle |
| JPH06218508A (en) * | 1993-01-28 | 1994-08-09 | Toshiba Ceramics Co Ltd | Dipping nozzle for continuous casting |
| JPH09285852A (en) * | 1996-04-23 | 1997-11-04 | Nippon Steel Corp | Continuous casting method, and immersion nozzle for continuous casting |
| CN1271303A (en) * | 1997-09-22 | 2000-10-25 | 丸川雄净 | Immersion nozzle |
| JP2001321901A (en) * | 2000-05-15 | 2001-11-20 | Sumitomo Metal Ind Ltd | Method for continuously casting steel |
| JP2003025048A (en) * | 2001-05-11 | 2003-01-28 | Nippon Steel Corp | Method for continuously casting steel |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1905966A (en) | 2007-01-31 |
| JP4508110B2 (en) | 2010-07-21 |
| JPWO2005070589A1 (en) | 2007-07-26 |
| US20070158884A1 (en) | 2007-07-12 |
| WO2005070589A1 (en) | 2005-08-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100398229C (en) | Immersion nozzle for continuous casting and continuous casting method using the immersion nozzle | |
| US9573189B2 (en) | Submerged nozzle for continuous casting apparatus | |
| EP2279816B1 (en) | Immersion nozzle for continuous casting | |
| EP1541258B1 (en) | Casting nozzle | |
| CN103442826A (en) | Submerged nozzle for continuous casting | |
| EP3065899A1 (en) | Nozzle for casting metal beams | |
| JP6577841B2 (en) | Immersion nozzle | |
| EP1854571B1 (en) | Refractory nozzle for the continous casting of steel | |
| JP4220840B2 (en) | Method for removing inclusions in tundish and weir used therefor | |
| JP3246181B2 (en) | Immersion nozzle for continuous casting | |
| CN2770832Y (en) | Submersed nozzle for sheet billet continuous casting | |
| CN102950275B (en) | Multi-hole continuous-casting submersed nozzle for square and round billets | |
| JP4265412B2 (en) | Metal continuous casting method | |
| MXPA06005561A (en) | Multi-outlet casting nozzle. | |
| EP2111316B1 (en) | A submerged entry nozzle | |
| CN113226594B (en) | Immersion nozzle | |
| KR20050021278A (en) | submerged entry nozzle for continuous casting | |
| JP2010167488A (en) | Immersion nozzle for continuous casting | |
| JP3697040B2 (en) | Immersion nozzle for continuous casting of steel and method for continuous casting of steel using the same | |
| JPH04238658A (en) | Immersion nozzle for continuous casting | |
| KR100485404B1 (en) | Partial Immersion Nozzle for Continuous Casting of Thin Slabs | |
| KR20240034747A (en) | immersion nozzle | |
| JPH05269557A (en) | Immersion nozzle for continuous casting | |
| CN102873290A (en) | Multi-stage shunting type continuous casting immersive water gap | |
| JP2007216272A (en) | Immersed nozzle |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20080702 Termination date: 20100122 |