Description:TECHNICAL FIELD
Present disclosure generally relates to a field of metallurgy. Particularly, but not exclusively, the present disclosure relates to a tundish of a continuous casting process. Further, embodiments of the present disclosure disclose a dam accommodated within the tundish for floating inclusions of a molten steel in the tundish.
BACKGROUND OF THE DISCLOSURE
Continuous casting process is well-established technology for solidification of molten steel and to obtain steel products. Continuous casting process involves flow of molten steel from a ladle to a mould through an intermediate vessel called as tundish. The molten steel enters the mold and exit the mold in a requisite shape and later gets solidified as long products such as billets, blooms etc. Tundish is generally used as a flow distributor and is intended to maximize the molten steel residence time to promote inclusion floatation.
During production of steel, non-metallic inclusions like sulphide, silicate and aluminate particles are created. These inclusions when exposed to molten steel under ambient atmosphere may lead to oxygen pickup. Additionally, various maintenance activities like cleaning of the refractory lining (alumosilicate, magnesite-chromate, and spinel solid crystal particles) in steel ladles and tundishes, interactions between the steel melt's physical and chemical properties during the production of steel, deoxidizing it, and casting (alumosilicates, nitrides, and sulphides), leads to creation of inclusions. These inclusions may results in undesired flaws in the final product, affecting the quality.
Considering the above, tundish equipped with a dam have been evolved. The dam is configured to generate a gas curtain to optimize the tundish configuration. The tundish because of the conventional configuration of the dam causes formation of dead zones and results in short circuiting. Further, conventional dams cause only a small portion of the inclusion particles to be eliminated, which thereby causes the some particles to be easily carried away by the flow of molten metal into the mold, affecting the quality of final product, which is undesired.
The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already
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known to a person skilled in the art. The present disclosure is directed to overcome one or more limitations stated above or any other limitations associated with the conventional arts.
SUMMARY OF THE DISCLOSURE
One or more shortcomings of the conventional techniques are overcome by a dam for a tundish, as disclosed. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.
In one non-limiting embodiment of the disclosure, a dam for a tundish is described. The dam includes a body which is defined with a base. The base is adapted to support the dam in the tundish. Further, the dam includes a plurality of walls extending from the base, where a portion of at least one wall of the plurality of walls is defined with a chamfered surface along with a plurality of openings on the chamfered surface. Furthermore, the dam includes a conduit which is disposed within the body and align with the plurality of openings, and is configured to purge inert gas through the plurality of openings into the tundish, to form an inert gas curtain.
In an embodiment of the disclosure, the plurality of walls includes a front wall extending upwardly along one side of the base, a rear wall extending upwardly along another side, opposite to the one side of the base and a side wall extending upwardly from the base, and adjoining ends of the front wall, the rear wall and top wall.
In an embodiment of the disclosure, the chamfered surface is defined angularly between the portion of the top wall and the front wall, and extends along a length of the top wall and the front wall.
In an embodiment of the disclosure, the plurality of openings are defined equidistant to each other on the chamfered surface.
In an embodiment of the disclosure, the dam includes a plurality of nozzles are present. At least one nozzle of the plurality of nozzles are disposed in each of the plurality of openings and fluidly coupled to the conduit through a channel.
In an embodiment of the disclosure, the conduit has diameter ranging between 4mm to 15 mm and diameter of each of the plurality of nozzles ranges between 2mm to 8mm
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In an embodiment of the disclosure, the plurality of nozzles are configured to regulate purging the inert gas into the tundish at a rate ranging between 5 liters per minute to 15 liters per minute.
In an embodiment of the disclosure, length of the channel ranges between 30 mm to 75 mm.
In an embodiment of the disclosure, length of the front wall ranges between 80 mm to 200 mm and length of the rear wall ranges between 100 mm to 250 mm.
In an embodiment of the disclosure, width of the top wall ranges between 25 mm to 80 mm and the width of the base ranges between 40 mm to 120 mm.
In an embodiment of the disclosure, the length of the chamfered surface ranges between 25mm to 50 mm.
In an embodiment of the disclosure, the chamfered surface includes an angle θ1 ranging between 110°-150° and angle θ2 ranging between 20°-155°.
In an embodiment of the disclosure, height of the dam ranges between 100 mm to 450 mm.
In an another non-limiting embodiment of the disclosure, a tundish for discharging a molten metal for solidification in a continuous casting process is described. The tundish includes a shell defined with a cavity which is configured to receive molten metal from a ladle shroud. Further, the tundish includes a pouring box disposed underneath the ladle shroud. The pouring box is configured to receive the molten metal from the ladle shroud and dispense the molten metal into the cavity of the shell. Furthermore. The tundish includes a dam, which is positioned in the shell and adjacent to the pouring box. The dam includes a body which is defined with a base. The base is adapted to support the dam in the tundish. Further, the dam includes a plurality of walls extending from the base, where a portion of at least one wall of the plurality of walls is defined with a chamfered surface along with a plurality of openings on the chamfered surface. Furthermore, the dam includes a conduit which aligns with the plurality of openings and are configured to purge inert gas through the aligned at least one opening into the tundish, to form an inert gas curtain.
In an embodiment of the disclosure, the shell comprises a refractory lining.
It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.
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The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
The novel features and characteristics of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiments when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
Figure. 1 illustrates a perspective view of a tundish, in accordance with some embodiments of the present disclosure.
Figure. 2 illustrates a sectional view of the tundish of Figure. 1.
Figure. 3 illustrates a perspective view of a dam disposed in the tundish, in accordance with some embodiments of the present disclosure.
Figure. 4 illustrates a perspective view of the dam, depicting a conduit, in accordance with some embodiments of the present disclosure.
Figure. 5 illustrates a side view of the dam depicting a channel and nozzle, and magnified view of portion ‘A’, in accordance with some embodiments of present disclosure.
Figures. 6 illustrates a front view of the dam of Figure. 3.
Figures. 7 and 8 illustrates a side views of the dam, in accordance with some embodiments of the present disclosure.
Figures. 9 and 10 illustrates the velocity vectors of the conventional tundish and the tundish of the present disclosure, respectively, in accordance with some embodiments of the present disclosure.
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Figures. 11 and 12 illustrate the velocity contours of the conventional tundish and the tundish of the present disclosure, respectively, in accordance with some embodiments of the present disclosure.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
While embodiments in the disclosure are subject to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the Figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular form disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.
It is to be noted that a person skilled in the art would be motivated from the present disclosure and modify various features of the dam and tundish, without departing from the scope of the disclosure. Therefore, such modifications are considered to be part of the disclosure. Accordingly, the drawings show only those specific details that are pertinent to understand the embodiments of the present disclosure, so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skilled in the art having benefit of the description herein.
The terms “comprises….a”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusions, such that a device or system comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such device or system. In other words, one or more elements in mechanism proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.
The following paragraphs describe the present disclosure with reference to Figures. 1 to 12. In the figures, the same element or elements which have similar functions are indicated by the same reference signs. With general reference to the drawings, a dam for a tundish is illustrated
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and generally identified with reference numeral 100 in the corresponding figures. Other features and elements of the dam is depicted by respective reference numeral [see list of reference numerals] in the corresponding figures and the same will be used corresponding to respective feature henceforth.
The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description. It is to be understood that the disclosure may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices or components illustrated in the attached drawings and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions or other physical characteristics relating to the embodiments that may be disclosed are not to be considered as limiting, unless the claims expressly state otherwise. Hereinafter, preferred embodiments of the present disclosure will be described referring to the accompanying drawings. While some specific terms directed to a specific direction will be used, the purpose of usage of these terms or words is merely to facilitate understanding of the present invention referring to the drawings. Accordingly, it should be noted that meaning of these terms or words should not improperly limit the technical scope of the present invention. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. It is to be understood that this disclosure is not limited to the specific devices, methods, applications, conditions, or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example and is not intended to be limiting of the claimed invention.
Generally, molten metal (8) from a furnace such as but not limiting to an electric arc furnace or a basic oxygen furnace [not shown in Figures] may be tapped into a ladle [not shown in Figures] and may shipped to a continuous caster [not shown in Figures]. The ladle may be placed into a casting position above the tundish (200). The tundish (200) is depicted in Figures.
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1 and 2, in the corresponding drawings. In an embodiment, the tundish (200) may be but not limiting to a single strand tundish, or a double strand tundish. The tundish (200) may be located between the ladle, delivering the molten metal (8) and a caster mould of the continuous caster. The tundish (200) may be large container for holding a reservoir of the molten metal (8). The tundish (200) may include a shell (201), which may be defined with a cavity (202). The cavity (202) may be configured to receive the molten metal (8) from a ladle shroud (3), that may extend into a portion of the tundish (200) [thus, cavity (202)]. In an embodiment, the shell (201) may include a refractory lining at its inner surface and an outer being metallic shell. Further, the tundish (200) may include a pouring box (5) which may be disposed within the tundish (200) underneath the ladle shroud (3). The pouring box (5) may be configured to receive the molten metal (8) from the ladle shroud (3) and dispense the molten metal (8) into the cavity (202) of the shell (201). In an embodiment, the pouring box (5) may be configured to absorb turbulence of the molten metal (8). In another embodiment, the molten metal (8) received in the cavity (202) may be fed to the caster at continuous or semicontinuous flow rate. The caster may include the caster mould which receives the molten metal (8) from a tundish outlet nozzle (6) also known as submersed entry nozzle for a caster mould.
During production of steel, non-metallic inclusions like sulphide, silicate and aluminate particles are created. These inclusions when exposed to molten steel under ambient atmosphere may lead to oxygen pickup. Additionally, various maintenance activities like cleaning of the refractory lining (alumosilicate, magnesite-chromate, and spinel solid crystal particles) in steel ladles and tundishes, interactions between the steel melt's physical and chemical properties during the production of steel, deoxidizing it, and casting (alumosilicates, nitrides, and sulphides), leads to creation of inclusions. These inclusions may results in undesired flaws in the final product, affecting the quality. Along with the inclusion entrapment the tundish also faces the issue of the formation of dead zones. The dead zones are formed due to poor circulation of molten metal inside the cavity of tundish. Since, effectively floating the inclusions from the molten metal in the tundish results in high quality final product from the continuous casting mould, the present disclosure provides a dam for positioning in the tundish, whose configuration aids effective floating of the inclusions in the molten metal.
Accordingly, embodiments of the present disclosure disclose, the dam (100) for the tundish (200). The configuration of the dam (100) will be explained in conjunction with Figures. 3 to 8 in the forthcoming paragraphs. The dam (100) may be made of refractory material including
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alumina, magnesia, silica, compounds and composites. The dam (100) may be positioned at the length Ld from the shroud (3). Typically, the length Ld lies in between 42% - 56% of the total length of the tundish (200) (LT). In an implementation, the dam (100) may be at least one of cuboidal, trapezoidal, parallelopoid or any other symmetric or asymmetric geometric shapes without deviating from the scope of the present disclosure. According to the embodiments of the present disclosure, the profile or shape of the dam (100) may be substantially rectangular. The profile of the dam (100) may be compatible with any configurations of the tundish (200) in which the dam (100) will be employed or disposed.
The dam (100) of the present disclosure as illustrated in Figure. 3 may include a body (101) which may be defined with a base (12). The base (12) may be adapted to support the dam (100) in the tundish (200). Further, the body (101) may be defined with a plurality of walls (14, 9, 11, 15) extending from the base (12). A portion of at least one wall of the plurality of walls (14, 9, 11, 15) may be defined with a chamfered surface (10). In an embodiment, the plurality of walls (14, 9, 11, 15) may include a front wall (14), which may extend upwardly along one side of the base (12). Further, the plurality of walls (14, 9, 11, 15) may include a rear wall (15), which may extend upwardly along another side, opposite to the one side of the base (12). Furthermore, the plurality of walls (14, 9, 11, 15) may include a side wall (11), which may extend upwardly from the base (12) and may adjoins ends of the front wall (14), the rear wall (15) [as seen in Figure. 7] and the top wall (9). In an illustrated embodiment, there are two ends of the front wall (14) and rear wall (15) to be joined, and the number of side walls (11) may be two. In an embodiment, the two side walls (11) may include an identical geometry. Further, the plurality of walls (14, 9, 11, 15) may include a top wall (9) which may extend between front wall (14) and the chamfered surface (10). In an embodiment, referring to Figure. 7, the front wall (14) may include length (L2) which may range between 80 mm to 200 mm and the rear wall (15) may include length (L1) which may range between 100 mm to 250 mm. Further, the top wall (9) may include width B2, which may range between 25 mm to 80 mm and base (12) may include width B1 which may range between 40 mm to 120 mm. The configuration of the dam (100) may aids in effectively deflecting the incoming molten steel (8) in the tundish (200) in a direction parallel to the top wall (9) of the dam (100), when the molten metal (8) contact the dam (100). This may result in reducing velocity of the incoming molten steel (8) to facilitate surfacing of the inclusions in the molten steel (8).
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Referring further to Figure. 3, the chamfered surface (10) may be defined on a portion of at least one wall of the plurality of walls (14, 9, 11, 15). In an embodiment, the chamfered surface (10) may be defined angularly between the portion of the top wall (9) and the front wall (14), and may extend along a length of the top wall (9) and the front wall (14). In an embodiment, as seen in Figure. 8, the chamfered surface (10) may include an angle θ1 ranging between 110°-150° and angle θ2 ranging between 20°-155°. Further, in an embodiment, the chamfered surface (10) may be defined with a plurality of openings (20a-20f). In an embodiment, the plurality of openings (20a-20f) may be defined equidistant to each other on the chamfered surface (10) to maintain the uniformity of the pattern of the inert gas curtain.
Turning now to Figure. 4, in an embodiment, the dam (100) may include a conduit (26), which may be disposed within the body (101). In an illustrated embodiment, the conduit (26) is disposed proximal to the top wall (9) and the chamfered surface (10). However, the same cannot be construed as a limitation since the conduit (26) may be positioned in any location within the body (101). In an embodiment, an inlet (27) of the conduit (26) may be fluidly coupled to an inert gas reservoir [not shown in Figures], and may be configured to receive the inert gas from the inert gas reservoir. Further, the conduit (26) may align with the plurality of openings (20a-20f). The conduit (26) may be configured to purge through the openings (20a-20f) into the tundish (200) to form an inert gas curtain (7). In an embodiment, diameter of the conduit (26) may range between 4mm to 15 mm.
Referring now to Figure. 5, the dam (100) may include a plurality of nozzles (13a-13f). At least one nozzle of the plurality of nozzles (13a-13f) may be disposed in each of the plurality of openings (20a-20f). The plurality of nozzles (13a-13f) may be fluidly coupled to the conduit (26) through a channel (25). The channel (25) may be configured to provide a passage for the inert gas to flow from the conduit (26) to the nozzle, such that the nozzle may purge the inert gas into the tundish (200) to create a curtain (7) of the inert gas in the tundish (200). In an embodiment as shown in Figure. 5, the channel (25) may include a length (L) ranges between 30 mm to 75 mm. In an embodiment, diameter of the plurality of nozzles (13a-13f) ranges between 2 mm to 8 mm. The diameter of the nozzles (13a-13f) aids in purging the inert gas with a desired bubble size which possess appropriate terminal velocity which aids efficient floatation of the inclusions and entrapment of the inclusions through its path. In an embodiment, the plurality of nozzles (13a-13f) may be configured to regulate purging the inert gas into the tundish (200) at a rate ranging between 5 liters per minute to 12 liters per minute.
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Purging the inert gas (thus, bubbles) at the rate of 5 liters per minute to 12 liters per minute aids in mitigating the phenomenon of tundish open eye by preventing inert gas flow through a top slag layer.
In an embodiment, the plurality of nozzles (13a-13f) disposed in each of the plurality of openings (20a-20f) in the chamfered surface (10), may be positioned at an angle ranging between 125 degrees to 140 degrees, due to the configuration of the chamfered surface (10). Positioning the plurality of nozzles (13a-13f) in this angle range may increase the interaction of the inert gas curtain (7) with the incoming molten metal (8) into the tundish (200). This aids effective floatation of the inclusions from the molten metal (8). Further, creating inert gas rinsing curtain (7) through the dam (100) placed in the tundish (200) enhances floatation of even the smaller size inclusions and favor minimum level of inclusion in the cast slab obtained of such forced inclusion floatation.
In an embodiment, the inert gas may be but not limiting to argon, which does not chemically interact with the molten metal (8), as well as being gas of lower molecular weight, non-radioactive, and easy availability among other inert gases makes it suitable to pursue embodiments of present disclosure.
In an illustrated embodiment as seen Figures. 3 & 6 the dam (100) includes six openings (20a-20f) [thus six nozzles (13a-13f)] in the chamfered surface (100). However, the same cannot be construed as a limitation, since the number of nozzles may vary based on the configuration and dimension of the dam (100). In an embodiment, the number of nozzles required may be determine based on parameters such as total length of the dam, length between two adjacent nozzles. Number of nozzles may be determined through equation (i)
I=Ln ….. Equation (i)
where,
L-Total length of the Dam (100)
I- Length between two adjacent nozzles
n- Number of nozzles
Determining the number of nozzles by the equation (i) aids in maintaining uniformity in maintaining the inert gas curtain.
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According to an operational embodiment of the present disclosure, a molten metal (8) stream flows from the ladle shroud (3) into the pouring box (5). The tundish (200) is filled with molten metal (8) up to a certain height of the tundish (200). Post filling of the pouring box (5), the molten metal (8) may flow towards the dam (100) and exits the tundish (200) through the nozzle (6) into the mould. The molten metal (8) when strikes the dam (100) gets deflected in a direction parallel to the dam (100) and velocity of the molten metal (8) reduces. At this point, inert gas is purged from the dam (100) [thus, the plurality of nozzles (18a-18f)] which interacts with the molten metal (8) flowing over the dam (100) and enhances floatation of the inclusions in the molten metal (8), due to enhanced interaction of the inert gas curtain (7) with surface of the molten metal (8), thus improving quality of the final steel product.
It is to be understood that a person of ordinary skill in the art may develop an apparatus and a system of similar configuration without deviating from the scope of the present disclosure. Such modifications and variations may be made without departing from the scope of the present invention. Therefore, it is intended that the present disclosure covers such modifications and variations provided they come within the ambit of the appended claims and their equivalents.
Example:
experiments have been conducted for the tundish (200) of the present disclosure and the tundish with dam of the conventional art. . figure. 9 and figure. 10 illustrates velocity vectors obtained by simulation of the conventional tundish and the tundish (200) of the present disclosure, respectively. as seen in figure. 10, there are more recirculation zones in tundish of the present disclosure having the dam (100), than the case of conventional tundish with dam. Due to more recirculation zones inside the tundish (200), there will be better mixing that will lead to reduction in dead zone regions. Further, the velocity contours observed while performing simulation can be seen in Figure. 11, and Figure. 12 of the conventional tundish and the tundish of the present disclosure, respectively. It was observed that the fluid flow characteristics in a tundish with inert gas curtain is favorable to the floatation and separation of inclusions from molten steel (8).
Further experiments have been carried out to determine total dead volume in the conventional tundish and the tundish of the present disclosure, and the results have been tabulated in Table 1. Further experiments have been carried out to determine peak concentration time in the
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conventional tundish and the tundish of the present disclosure, and the results have been tabulated in Table 2.
Design
Total Dead Volume (m3)
Percentage Change
Conventional Tundish
0.767
15 %
Tundish of the present disclosure
0.65
Table. 1
From the above Table. 1, its clear that dead volume in the tundish of the present disclosure is lesser which aids in better performance of the tundish.
Design
Peak Concentration Time (sec)
Percentage Change
Conventional Tundish
374
17 %
Tundish of the present disclosure
451
Table. 2
Table. 2 displays that the peak concentration of the tracer is detected earlier in case of tundish with the argon rinsing mechanism. This signifies that the tundish with the argon rinsing mechanism has more laminar flow than its counterpart. The laminar flow aids into better homogeneity and distribution thereby better performance of tundish.
Equivalents:
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open”
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terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances, where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtua1lly any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.” While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and
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embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
Referral numerals:
Feature
Numeral
200
Tundish
100
Dam
101
Body
201
Shell
202
Cavity
3
Ladle Shroud
5
Pouring box
6
Tundish outlet nozzle
7
Inert gas curtain
8
Molten Metal
9
Top Wall
10
Chamfered Surface
11
Side Wall
12
Base
13a-13f
Nozzles
14
Front Wall
15
Rear Wall
25
Channel
26
Conduit
27
Inlet
20a-20f
Openings , Claims:We Claim:
1. A dam (100) for a tundish (200), the dam (100) comprising:
a body (101) defined with:
a base (12) adapted to support the dam (100) in the tundish (200);
a plurality of walls (14, 9, 11, 15) extending from the base (12), wherein a portion of at least one wall of the plurality of walls (14, 9, 11, 15) is defined with a chamfered surface (10); and
a plurality of openings (20a-20f) on the chamfered surface (10);
a conduit (26) disposed within the body (101) and align with the plurality of openings (20a-20f), wherein the conduit (26) is configured to purge an inert gas through the plurality of openings (20a-20f) into the tundish (200), to form an inert gas curtain (7).
2. The dam (100) as claimed in claim 1, wherein the plurality of walls (14, 9, 11, 15) comprises:
a front wall (14) extending upwardly along one side of the base (12);
a rear wall (15) extending upwardly along another side, opposite to the one side of the base (12);
a top wall (9) extending between top sides of the front wall (14) and the rear wall (15); and
a side wall (11) extending upwardly from the base (12) and adjoining ends of the front wall (14), the rear wall (15) and the top wall (9).
3. The dam (100) as claimed in claim 2, wherein the chamfered surface (10) is defined angularly between the portion of the top wall (9) and the front wall (14), and extends along a length of the top wall (9) and the front wall (14).
4. The dam (100) as claimed in claim 1, wherein the plurality of openings (20a-20f) are defined equidistant to each other on the chamfered surface (10).
5. The dam (100) as claimed in claim 1, comprising a plurality of nozzles (13a-13f), wherein at least one nozzle of the plurality of nozzles (13a-13f) are disposed in each of the plurality of openings (20a-20f) and fluidly coupled to the conduit (26) through a channel (25).
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6. The dam (100) as claimed in claim 5, wherein diameter of the conduit (26) ranges between 4mm to 15 mm and diameter of each of the plurality of nozzles (13a-13f) ranges between 2mm to 8mm.
7. The dam (100) as claimed in 5, wherein the plurality of nozzles (13a-13f) are configured to regulate purging the inert gas into the tundish (200) at a rate ranging between 5 liters per minute to 15 liters per minute.
8. The dam (100) as claimed in claim 5, wherein length (L) of the channel (25) ranges between 30 mm to 75 mm.
9. The dam (100) as claimed in claim 1, wherein length (L2) of the front wall (14) ranges between 80 mm to 200 mm and length (L1) of the rear wall (15) ranges between 100 mm to 250 mm.
10. The dam (100) as claimed in claim 1, wherein width B2 of the top wall (9) ranges between 25 mm to 80 mm and the width B1 of the base (12) ranges between 40 mm to 120 mm.
11. The dam (100) as claimed in claim 1, wherein length (L3) of the chamfered surface (10) ranges between 25 mm to 50 mm.
12. The dam (100) as claimed in claim 1, wherein the chamfered surface (10) comprises an angle θ1 ranging between 110°-150° and angle θ2 ranging between 20°-155°.
13. The dam (100) as claimed in claim 1, wherein height of the dam (100) ranges between 100 mm to 450 mm.
14. A tundish (200) for discharging a molten metal (8) for solidification in a continuous casting process, the tundish (200) comprising:
a shell (201) defined with a cavity (202) and configured to receive the molten metal (8) from a ladle shroud (3);
a pouring box (5) disposed within the tundish (200) underneath the ladle shroud (3), the pouring box (5) is configured to receive the molten metal (8) from the ladle shroud (3) and dispense the molten metal (8) into the cavity (202) of the shell (201);
a dam (100) positioned in the shell (201) and adjacent to the pouring box (5), the dam (100) comprising:
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a body (101) defined with:
a base (12) adapted to support the dam (100) in the tundish (200);
a plurality of walls (14, 9, 11, 15) extending from the base (12),
wherein a portion of at least one wall of the plurality of walls (14, 9, 11, 15) is
defined with a chamfered surface (10); and
a plurality of openings (20a-20f) on the chamfered surface (10);
a conduit (26) disposed within the body and align with the plurality of openings
(20a-20f), wherein the conduit (26) is configured to purge an inert gas through the plurality
of openings (20a-20f) into the tundish (200), to form an inert gas curtain (7).
15. The tundish (200) as claimed in claim 14, wherein the shell (201) comprises a refractory
lining.
16. The tundish (200) as claimed in claim 14, wherein the dam (100) with plurality of walls
(14, 9, 11, 15) comprises:
a front wall (14) extending upwardly along one side of the base (12);
a rear wall (15) extending upwardly along another side, opposite to the one side
of the base (12); and
a side wall (11) extending upwardly from the base (12) and adjoining ends of
the front wall (14) and the rear wall (15).
17. The tundish (200) as claimed in claim 14, wherein the chamfered surface (10) is defined
angularly between the portion of the top wall (9) and the front wall (14) and extends along
a length of the top wall (9) and the front wall (14).
18. The tundish (200) as claimed in claim 14, wherein the dam (100) comprising a plurality of
nozzles (13a-13f), wherein at least one nozzle of the plurality of nozzles (13a-13f) are
disposed in each of the plurality of openings (20a-20f) and fluidly coupled to the conduit
(26) through a channel (25).