MXPA98004399A - Improved metalurgical recipient and method for using the mi - Google Patents

Abstract

The present invention relates to a metallurgical vessel for retaining a molten metal having a slag layer thereon, comprising: a shell having a metallic exterior and an interior coated with refractory, the interior coated with refractory having sides and a inclined inner surface exposed to the interior of the container, and wherein the sloped lower surface has a tapered upper surface ending in a vertical surface, the vertical surface ending in a lower tapered surface forming a cavity block reservoir, the block reservoir of cavity having a volume of less than or equal to about five percent of the total volume of the metallurgical vessel, and wherein the cavity block reservoir includes a tap hole placed on the lower tapered surface to drain the molten metal from the metallurgical vessel.

Description

IMPROVED METALLURGICAL RECIPIENT AND METHOD FOR USING THE SAME REFERENCE TO RELATED REQUESTS This application is a continuation in part (according to C.F.R. S 1.53) of the Patent Application of E.U.A. No. 08 / 589,709 filed on January 22, 1996 (pending). The entirety of said patent application is specifically incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to improved metallurgical vessel and a method for employing same to improve the efficiency of use of high temperature metallurgical vessels and more particularly relates to providing an increase in usable amount. of molten metal removed from said containers. 2. Brief Description of the Prior Art As will be recognized by those skilled in the art, in high temperature containers such as molten steel buckets, a hitherto encountered problem relates to preventing slag from contaminating or otherwise mixing with steel relatively pure when it is being removed from the container. Since the slag is less dense than the molten steel, the slag tends to rise and accumulate on the underlying steel. If a pouring orifice is provided in the bottom of the container, relatively uncontaminated molten steel can be removed by simply opening the orifice to allow liquid steel to exit therethrough. However, when the liquid surface falls until it is near the bottom of the container, the casting must be stopped before the slag comes out with the remaining steel; and in this way an amount of steel remaining in the container is unusable. In order to keep this unusable amount of molten metal as small as practicable, it has become customary to provide sloping bottoms at or near the edge of the container where the pouring hole is placed. However, this has caused a relative inefficiency in the installation and use of refractory brick. A variety of designs and processes have been proposed to improve the efficiency of metallurgical vessels, such as, for example, cast steel buckets. The Patent of E.U.A. No. 5,196,051 (Heaslip et al) discloses bucket bottom geometries having sloped surfaces on which pluralities of notches are placed to reduce vortices that would otherwise trap slag or other impurities in the exit liquid as the void is emptied. ladle. The Patent of E.U.A. No. 4,746,102 (Gilles et al.) Discloses a multiple diameter drain hole design and a drain hole closure valve at the bottom of the metallurgical bucket to reduce the loss of performance from the metallurgical bucket where the Metallurgical ladle has the liquid metal that has a layer of slag on the liquid metal. Despite this background material, there is a very real and substantial need for an improved metallurgical vessel to increase the utilization efficiency of refractory brick and / or to increase the amount of usable molten metal, such as steel, which can be squeezed from the metallurgical vessel, such as, for example, a ladle. It will be appreciated by those skilled in the art that due to the large size and retention capacities of typical buckets and the volume of steel normally carried therein, even a relatively small percentage increase in volumetric efficiency results in an absolute large volume. and correspondingly large cost savings provided substantial economic advantages.

COMPENDIUM OF THE INVENTION The present invention has met the needs described above. The present invention provides a metallurgical vessel for retaining a molten metal having a layer of slag thereon. The metallurgical vessel comprises a shell having a metallic exterior and a riprapied interior with refractory wherein the refractory-lined interior has sides and a sloping bottom surface. The sloping lower surface has a tapered upper surface that terminates on a vertical surface; the vertical surface terminated in a lower tapered surface forming a cavity block reservoir. The cavity block reservoir of the present invention has a volume of less than or equal to about five percent of the total volume of the metallurgical vessel. The cavity block reservoir includes a pouring orifice (i.e. bypass hole) placed on the lower tapered surface to drain the molten metal from the metallurgical vessel. The improved metallurgical vessel of the present invention provides the cavity block reservoir for the formation of an increased depth tank in ßl which, for example, will accumulate the molten metal residue and slag when the Bucket is almost empty during discharge of steel from the metallurgical vessel. Consequently, the amount of usable steel increases significantly, thus contributing to the improved volumetric efficiency of the metallurgical vessel. A method is also provided for improving the efficiency of performance of a metallurgical vessel for retaining a molten metal having a slag layer thereon which employs the metallurgical vessel of the present invention.

OBJECTS AND PARTICULARITIES OF THE INVENTION A general object of the invention is to improve the volumetric efficiency of metallurgical containers coated with high temperature refractory. Another object of the invention is to facilitate the use of said containers in which the bottoms are inclined either sideways or towards the center. Accordingly, in accordance with a particular feature of the invention, a small, but deep, well-like reservoir (i.e., cavity block reservoir) is provided adjacent to the reservoir exit orifice, thereby increasing the volume of liquid metal in the reservoir. Relatively high elevated temperature that can be sneaked from the container. In accordance with another feature of the invention, the small well-like reservoir (ie, cavity block reservoir) is disposed in the outlet orifice of the container, thereby further contributing to the drainage efficiency of the reservoir. liquid content not contaminated. These and other objects and features of the invention will become apparent from the following description, by way of example. of preferred embodiments, with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a top view of a typical refractory lined container used to handle molten metal. Figure 2 is a partial sectional view, taken along section lines 2-2 of Figure 1. Figure 3 is a partial sectional view, taken along section lines 3-3 of the Figure 1. Figure 4 is a top view of a preferred universal configuration for practicing the invention. Figure 5A is a side view of the configuration of Figure 4. Figure 5B is a side view of an alternative configuration to that shown in Figure 5A. Figure 6 is a perspective view illustrating one of two half semicircular rings of refractory bricks configured in accordance with the invention. Figure 6A is a perspective view illustrating a multi-unit prefabricated module of a part of the ring means of Figure 6. Figure 6A1 is a perspective view illustrating a single unit prefabricated module as a part of the ring half of Figure 6. Figure 6B is a perspective view illustrating a multi-unit prefabricated module of another part of the ring means of Figure 6.

Figure 6B 'is a perspective view illustrating a single unit prefabricated module of another part of the ring means of Figure 6. Figures 7, 7A, and 7B are linear views (elevations) illustrating a modification of Figure 6 in which two rows of refractory bricks remain one above the other in the main part of the semicircle, while the thinnest end is comprised of only one layer only. Figures 8, 8A and 8B show a top view illustrating the tapered refractories of the general type shown in Figure 4. Figure 9 is a top view of the container of Figure 1 when using quarter-circular modules with bottom extensions . Figure 9A is a top view of the container of Figure 1 including a cavity block reservoir in accordance with the present invention. Figure 10 is a top view of the container of Figure 1 including a cavity block reservoir in accordance with the present invention, except that it includes a central pouring hole instead of a deviated pouring hole. Figures HA and 11B are sectional views of the sloping bottom surface and the cavity block deposit of the metallurgical vessel of the present invention. Figure 12 shows the performance improvement achieved using the present invention in relation to current practice.

DETAILED DESCRIPTION OF THE INVENTION As used herein, the term "cavity block deposit" means a region surrounding or in another geometric union with a pouring orifice (ie, bypass hole) at the bottom of a metallurgical vessel having a background covered with refractory. The pouring hole is a hole in the bottom of the container through which a liquid material, such as for example but not limited to. molten steel, drained from the container. Although the present invention is applicable to metallurgical containers extensively, it will be described in relation to ladles. Turning now to the drawing, and more particularly to Figure 1 thereof, it will be seen that it illustrates a typical circular metallurgical vessel, such as for example the bucket 10 used in the steelmaking industry to handle molten metal such as, for example, steel. . The container typically includes an outer metallic shell 11, a first shell of refractory bricks 12, and an internal coating of refractory bricks 13. Included within the inner bottom are the pour hole 14, and the injector locations 15 and 16. The injectors are not necessarily used in all the buckets. The pouring hole is preferably located at or near the lowest point of the sloping bottom of the container which, in the embodiment of Figure 1, is deviated (as shown) from the center to a location adjacent to the outer wall. The deviation for injectors 15 and 16 as shown in figure 1 is to accommodate other equipment. To further illustrate the interior of the metallurgical vessel shown in Figure 1 and to illustrate the refractory leveling rows constructed in accordance with the present invention, sections 2-2 and 3-3 are shown respectively in Figures 2 and 3. Figure 2 shows two layers 17 and 18 of refractories that typically coat the bottom of high temperature metallurgical containers, such as, for example, liquid steel handling containers. It will be noted that Figure 2 shows these two layers 17 and 18 which are each generally of uniform thickness and are installed to present an inclined upper surface 19 of the element 18 which slopes down towards the pouring hole 14 (not shown) of way to facilitate the drainage of molten metal, for example, steel, from the container. As mentioned above, this inclined surface provides advantages. However, in order to provide the aforementioned leveling. The present invention provides a pair of tapered layers 20 and 21 which are installed such that the upper surface 22 of the layer 21 is essentially leveled as shown in Figure 2. Accordingly, Figure 2 shows successive rows of bricks as shown in FIG. represented by the rows 23 and 24 which are essentially parallel to the plane containing the mouth (not shown) of the container 10 so that the row of refractories more resistant to slag (and expensive) described above needs to be of minimum height . If the dimensions of the bucket are such that the ends of the tapered layers 20 and 21 are not adjacent, they can be made to communicate, that is, to form a ring with the use of transitional refractories. At both ends of the tapered layers 20 and 21 are shown refractory 25a / 25b and 26a / 26b transition, respectively, which connect with the layers and meet the conventional side wall refractories 27 and 28, respectively. The refractories 25a / 25b and 26a / 26b are divisions or bricks that are not tapered and are of the same thickness (height) of the adjacent brick in the ring. Figure 3 shows the geometric relationship of the refractory rows before a 90 degree angle to that of Figure 2; and similar parts, of course, are identified with similar symbols. There, the leveling rows 20 and 21 are shown, with the surface 22 of the layer 21 being essentially level, and with the line 29 between the layers 20 and 21 reflecting the tapered and curved nature of the interior of the container. Figures 4, 5A and 5B show refractory configurations in accordance with a first preferred embodiment of the present invention. Figure 4 is a top view of a particular preferred universal configuration 30 for practicing the invention. Complete universal configurations having equal internal and external faces are preferred since the same configurations for the two half rings can be used. Semi-universal configurations are also appropriate, but due to their thick taper, they require left and right configurations that have taper in opposite directions, or one of the half mirror image rings must be inverted. Semi-universal bricks of key, circle, wedge, and the like are also suitable. Figure 4 shows that the refractory configuration 30 includes a pair of substantially parallel surfaces 31 and 32, together with a pair of curved surfaces 33 and 34 that are complementary and provide shape adjustment of adjacent bricks as set forth in Figure 6. Figure 5A is a side view of the refractory brick of Figure 4 and illustrates the characteristic of tapering that results in compensation as described herein. In this way, the height of the brick at the end 33 as measured by the dimension 35 is greater than the height of the brick at the end 34 as indicated by the dimension 36; and the difference, as represented by dimension 37, results in a controlled taper in brick height that is progressive as set forth in Figure 6. In this way, the height of each brick in the half circle ring representative of the Figure 6 is different from each adjacent brick so as to result in a smooth taper from the left end 40 to the right end 41 as shown. Also, it should be noted that at the far right, the much lower refractories (shorter) are shown and their relevant surfaces are identified by lps numbers 32a and 34a. Figure 5B illustrates another embodiment of the present invention in that the taper as evidenced by the dimension 37 of Figure 5 is divided into two parts 37a and 37b which is present on opposite surfaces. It will be understood by those skilled in the art that in order for compensation to occur (as described herein) of the present invention, the amount of taper is determined by the degree to which the lower refractories 17 are tilted (Figure 2). of the container 10 as shown by the inclination of the upper surface of the element 19 (Figure 2). Therefore, the amount of taper from the left end 40 to the right end 41 (Figure 6) will vary depending on the taper of the lower tilt of the container. Figure 6 is a perspective view illustrating one of two half semicircular rings of semi-universal refractory bricks configured in accordance with the invention, the complementary semicircular ring means being a mirror image of the ring means shown. Figure 6 shows that there are two rows of essentially identical refractories, one remaining over the other. To complete the complete ring, the mirror image rows are placed together at the ends 40 and 41 to complete a circular installation as illustrated in Figures 1-3. It will be understood by those skilled in the art that the number of rows of bricks will vary depending on the inclination of the bottom of the container and the taper of the bricks. To join two half rings, tapered brick of left and right hand is required. To avoid additional mold costs, a more practical approach is to cut the ends of both rows so that they coincide on a flat vertical surface. If the cut is not possible, the spaces in the opposite faces of the half rings can be filled with monolithic refractory. This practice is not recommended but if it is impossible to avoid, high-strength refractory plastic or tamping mix should be used. As mentioned herein, one of the features of the invention is its adaptability for modular prefabrication. Figures 6A and 6B illustrate modules 55 and 56 of multiple elements that when assembled together, form a ring means similar to that illustrated in Figure 6. In this way, it will be observed by those skilled in the art that in order to assemble the Modules of Figures 6A and 6B, identified with numbers 57 and 58 are put in communication with each other. An additional examination of Figure 6B reveals the presence of hyphen lines 59, 60 and 61. These hyphen lines represent an optional addition to the module of a pie configuration segment 62 comprising a pro-rated portion of the refractory covering the bottom. of the container. The apex 63 (Figure 6B) of said pie-shaped segment can be truncated in embodiments having a central pouring hole so as to remove the small region 64 and leave room for insertion of a refractory lined pouring nozzle (no. shown). It will be apparent from those experiments in the art that a similar cake-shaped extension can be attached to each of the remaining modules such as, for example, the module 55 (Figure 6A). The modules of Figures 6a and 6B can also be formed as unitary molded or tamped modules 55 'and 56' (as illustrated in Figures 6A 'and 6B') that when assembled together, form a half ring similar to that of Figure 6. In this way, in order to assemble the modules of Figures 6A 'and 6B', the ends identified with the numbers 57"and 58 'are put in communication with each other. A further examination of Figures 6A 'and 6B' reveals the presence of the hyphen lines 69 ', 60' and 61 'These hyphen lines (Figure 6B) represent the optional addition described above of the module of a segment 62' of cake form comprising a pro-rated part of the refractory covering the bottom of the container The apex 63 'of said pie-shaped segment may be truncated in embodiments having a central pour hole so as to eliminate the small region 64' and leave room for insertion of a refractory-coated pour hole nozzle (not shown) It will be observed by those skilled in the art that an extension of similar pie configuration can be attached to each of the remaining modules, such as For example, the module 55 '(Figure 6A'). Figure 7 is a side view illustrating a modification of Figure 6 in which two rows of bricks lie one over the other in the main part of the semicircle, while the thinner end is comprised of a single layer only. In this manner, at the left end 42 the overlapping nature of the rows is represented by overlapping the refractories 30a and 30b which in an illustrative embodiment result in a total row height at the end 42, such as for example. but not limited, to approximately 21.59 centimeters, as shown by dimension 43. In this modality, the double geometry of the rows continues to point 44 in which the total height has declined so that the rest includes just one brick 45. In the illustration hereof, the height at end 46 has decreased as for example, but not limited to 3.18 centimeters, as shown by dimension 47. For embodiments corresponding to those of Figures 6A and 6B, they may be provided. sections similar to sections 70 and 71 as shown in Figures 7A and 7B, respectively. There, the ends (Figure 7A) and 73 (Figure 7B) are put in communication when the sections are assembled. As mentioned herein, the principles of the present invention may have applicability to non-circular containers; and to illustrate this, the arrangement shown in Figure 8 is included. Figure 8 shows a top view illustrating tapered refractories of the general type shown in Figure 4. Beginning at the left end 49 of the arrangement, there are rows 50- 50d that continue to the right end 51 that ends with the 50cc row.

As with the configurations described above, the degree of taper provided by the refractories 50 to 50cc is complementary to the corresponding inclination of the bottom surface of the container in which they are to be installed in order to provide leveling compensation. In this way, the principle can be applied to coatings comprising both curved and flat surfaces. Again, to illustrate the adaptability to modular prefabrication techniques, modules 75 (Figure 8A) and 76 (Figure 8B) are shown that, together, correspond to the arrangement of Figure 8. Again, as will be apparent to those skilled in the art. the branch, assembling the modules involves bringing the ends 77 (Figure 8) and 78 (Figure 8B) in communication with one another. Figure 9 shows a top view of the container of Figure 1 when quarter-circle modules with lower extensions (such as those represented by the module 56 'and pie slice segment 62' extending downwardly of Figure 6B ') are in place, and showing the slice-like sections of pie 62a-62d of the lower refractory material. It will be noted from those experiments in the art that the pie slice sections 62b, 62c and 62d are modified as needed to accommodate the diverted pour hole and the injector locations (i.e., the injector ports) 15 and 16. It will also be noted that lines 80, 81, 82 and 83 (Figure 9) represent communication lines between adjacent pie slices. Figure 9A shows another embodiment of the present invention and is a view similar to that of Figure 9, except that Figure 9A schematically shows a cavity block reservoir 14b in accordance with the most preferred embodiment of the invention. the present. As is known to those skilled in the art, when the molten metal is ready to sneak into a metallurgical vessel such as, for example, a ladle, with the slag blanket remaining essentially on the free surface of the metal, such as, for example, steel , a portion of the slag is transferred to the ladle. It is customary in the field to fill a ladle with molten metal with a slag layer above the molten metal of approximately 5.04 to 25.40 centimeters or more in depth. An inert gas, such as, for example, argon, is bubbled through the molten metal through the injection locations (i.e., injector ports) toward the bucket to homogenize the metal, thereby releasing the trapped metal slag. liquid and to reset and redefine the slag-metal interface, as mentioned above. The ladle is then drained through a pouring orifice (ie, casting hole) at a predetermined rate depending on the molding regime. The drainage regime of the ladle is controlled with a pour hole cover element such as for example, but not limited. to a sliding gate mechanism at the bottom of the pouring orifice (ie, pouring hole). As the molten metal is drained from the bucket, the slag layer remains on top of the molten metal until the level is drained from the bucket, the slag layer remains on top of the molten metal until the level of molten metal approaches the bottom of the ladle. The slag then pulls down into the discharge stream and becomes trapped in the molten steel. This entrapment causes unacceptable impurities and surface defects in the final product. So far, the bucket drain stopped prematurely resulting in several tons of unusable molten metal remaining in the bucket. As described herein, the most preferred embodiment of the present invention, an improved metallurgical vessel increases the yield of usable steel available when the metallurgical vessel is drained. The most preferred embodiment of the present invention, as set forth in Figures HA and 11B, provides a metallurgical vessel for retaining the molten metal having a slag layer thereon comprising a shell 108 having a metallic exterior and a refractory lined interior. The refractory lined interior has sides 106 and a sloped bottom surface 112 exposed to the interior of the container. The lower sliding surface 112 of the container has a tapered upper surface 112a terminating in a vertical surface 112b. The vertical surface 112b terminates at a lower tapered surface 112c to form a cavity block reservoir 120. The cavity block reservoir 120 has a volume of less than or equal to about five percent of the total volume of the metallurgical vessel. In another embodiment of this invention, the cavity block reservoir 120 includes a pouring hole 110 placed in the lower tapered surface 112c for draining the molten metal from the metallurgical vessel. It is preferred that the inclined lower surface 112 of the container has an angle of inclination greater than or equal to about three degrees. More preferably, the cavity block reservoir 120 has a volume of less than or equal to about three (3) percent of the total volume of the metallurgical vessel. Another embodiment of this invention includes providing an impact pad (not shown in FIGS. 11 and 11b), as is known to those skilled in the art, placed on the inclined lower surface 112 of the container. It will be observed by those skilled in the art that the pouring hole of the metallurgical vessel of the present invention is advantageously positioned close to or preferably placed in a lower region of the cavity block reservoir. In this way, the pouring hole may be offset in the cavity block reservoir area or the pouring hole may be placed in the center of the cavity block reservoir. Another embodiment of the present invention provides a method for improving the efficiency of performance of the metallurgical vessel for retaining a molten metal having a slag layer thereon which comprises employing a metallurgical vessel comprising a shell having side walls and a bottom for forming an interior of the metallurgical vessel to contain a molten metal; forming a refractory lining that covers the inside of the side walls and the bottom of the container wherein the refractory lining forms a sloped bottom surface exposed to the interior of the container, wherein the sloped bottom surface has a tapered top surface that terminates on a vertical surface , the vertical surface ending in a lower tapered surface to form a cavity block reservoir, the cavity block reservoir having a volume of less than or equal to about five percent of the total container volume, and the reservoir block cavity having a pouring orifice (ie, pouring orifice) having an opening positioned in the lower tapered surface to provide drainage of the container, wherein the pouring hole has a removable pouring-hole covering element in juxtaposition to the hole casting to open and close the pour hole opening; placing the removable pour hole cover element in the closed position below the pour hole opening; placing the molten metal into the container and allowing sufficient volume for a layer of slag on the molten metal within the container for the formation of the interface of molten metal and slag; draining the container to move the removable casting cover element in the open position to allow the molten metal within the container to collect in the cavity block reservoir and then pass through the pouring hole opening; and moving the removable casting cover element in the closed position simultaneously with, before or after the entry of the slag into the cavity block reservoir to increase the yield of usable molten metal discharged from the container. In a preferred embodiment, the method of this invention, as described herein, includes employing the inclined bottom surface having an angle of inclination greater than or equal to approximately three (3) degrees. In a more preferred embodiment, the method of this invention, as described herein, includes employing a cavity block reservoir having a volume of less than or equal to about three (83) percent of the total volume of the container. In a preferred embodiment, the method of this invention, as described herein, includes placing the positioning hole near or in the lower region of the cavity block reservoir. It will be appreciated by those skilled in the art that the cavity block reservoir of the present invention can be employed alone or in combination with the metallurgical vessel brick leveling set or pre-molded module leveling assembly as described herein. In this way, it will be understood by those skilled in the art that the present invention preferably provides an optimum tilt for most or all of the bottom of the vessel coupled with a discrete well or reservoir, i.e., the cavity block reservoir as shown in FIG. described herein, adjacent to the pouring orifice (ie, the pouring hole) where a region is provided for a small pond of increased depth in which the residue of molten metal and slag accumulate when the container is almost empty . Consequently, the amount of usable metal is significantly increased, thus contributing to the improved volumetric efficiency of the container. Said cavity block deposit is identified by reference symbol 14b in Figure 9A; and preferably surrounds the otherwise existing drain or pour hole (ie, pour hole) 14 of the metallurgical vessel. Figure 10 is a top view of a typical refractory lined container similar to that of Figure 1, except that it includes a central pour hole instead of a diverted pour hole as was the case with the container shown in Figure 1 Figure 10 shows the injector locations 15 and 16 together with a centrally positioned casting hole 14 and the cavity block reservoir 14b of the present invention surrounding the casting hole 14. Since, as mentioned above, it is more desirable to place the pouring hole at the lowest point in the bottom of the container, it will be noted that the bottom of the container 10 slopes downward (and preferably symmetrically) from the shell 11 of external steel and its internal periphery adjacent the coating 12 inside the pouring hole 14. In such a case, the compensation for the inclined bottom can be made with identical refractories, each having a flat upper part and an inclined bottom, the inclination of which corresponds to the inclination of the adjacent part of the bottom of the container. Figure 11B sets forth a sectional schematic view of another example of the preferred embodiment of this invention similar to Figure HA and with elements having identical numerical designations where applicable, wherein the sloping lower surface 112 and the reservoir 120 cavity of the present invention for increasing the yield of usable metal discharged from a metallurgical vessel is shown. Figure 11B shows, for example, a precast or monolithic casting in place of the refractory 105 together with rows of sidewall refractories 106 and safety refractories 107 thereon. The flange 113 extends upwards to a height such that the upper surface thereof is substantially the same horizontal plane of the upper surface 113b of the refractory 105. In Figure 11B, the steel shell 108 has a flat bottom 109 with an opening pouring 110 (ie, pouring hole). The monolithic preforming or molding in place of the refractory lining 105 has a bottom surface 111 parallel to the adjacent internal horizontal bottom surface of the shell 108. However, in order to provide the aforementioned inclined interior surface for contact with metallurgical liquid, the preform or molding in place of the refractory lining contains an inclined lower surface 112 which slopes downwardly (as shown) to a low point in the pouring orifice 110 (ie, pouring hole). The integral overlying shoulder 113 provides compensation for the inclined monolithic bottom 105. The side wall refractory liner, such as for example but not limited to. either brick or monolithic, it is then added to the generally horizontal faces 113a / 113b. In the arrangement shown in Figure HA, the lower surface 111 of the refractory lining 105 extends to the container shell 108. alternatively, a construction may be employed by which the side walls extend to the bottom of the shell (not shown). In this case, the bottom can be installed inside the side walls. It will also be apparent to those skilled in the art that one or more security coatings 107 can be used between the pre-molded refractory 105 and the steel shell 108. It will be appreciated by those skilled in the art that the present invention provides numerous advantages over the prior art. First, the present invention does not require expensive modification of the existing pour hole or drainage hole (ie, pour hole) in its structure of an existing metallurgical vessel. Second, the present invention provides a metallurgical vessel having a cavity block reservoir, as described herein, that optimizes drainage of the liquid metal thereby resulting in a lower amount of unusable metal (i.e., entrapped metal). of slag) that remains at the bottom of the container after the container is discharged. Therefore, it will be noted that the present invention provides the optimum displacement of liquid metal and, thus, results in a very significant volumetric performance improvement of usable metal. This translates into a tremendous economic benefit for metal producers, such as, for example, in the steel industry. Third, the present invention provides an improved metallurgical vessel for increasing the usable volumetric metal yield which does not require change in the overall bucket steelmaking practice, including, but not limited to, not requiring any changes in molding practices, furnace of basic oxygen or electric arc furnace practices. Fourth, the present invention, which provides the metallurgical container having the cavity block reservoir, as described herein, does not require an increase in time of new working coating line, does not require additional capital investment by the producer metal and does not require an increase in work time. Finally. the metallurgical vessel having the cavity block reservoir of this invention does not adversely affect the free bucket of openings, as will be observed by those skilled in the art. In this way, it will be understood by those skilled in the art that the present invention not only solves a long-time unfilled need in the metal industry to increase the amount of usable metal discharged from a metallurgical vessel, but also provides the additional economic advantages noted above. Figure 12 shows the metal performance now that results from the improvement provided by the metallurgical vessel of this invention. Figure 12 shows the volume (in cubic feet) of unusable steel that remains in a bucket based on the inches of unusable liquid steel that remains at the bottom of the bucket after the bucket was unloaded. Figure 12 shows the results when three buckets of uniform size, but of different design, were compared to quantify the amount of unusable liquid steel that remains in the bottom of the bucket after the discharge of the steel or ilizable from the bucket. Bucket 1 is a conventional known bucket in the industry, a flat bottom bucket. The ladle 2 is one known in the industry, conventional, is a bucket with sloping bottom. Bucket 3 is a bucket having an inclined bottom and cavity block reservoir in accordance with the present invention. Each ladle was equipped with a conventional non-proprietary pouring orifice (ie, casting hole assembly). Figure 12 shows that there were 5.08 centimeters of unusable liquid steel corresponding to 70.79 liters of unusable liquid steel that remains in ladle 2 (which has an inclined bottom design) after the unloading of Bucket 2. Figure 12 shows that there were 5.08 centimeters of unusable liquid steel corresponding to 22.65 liters of unusable liquid steel that remain in Bucket 3 of the present invention after the discharge of Bucket 3. In this way it will be observed by those skilled in the art that the present invention (bucket 3) resulted in achieving the highest reduction in the loss of performance of liquid steel. Expressed otherwise, it will be understood by those skilled in the art that the metallurgical vessel of the present invention (Bucket 3) achieved the highest performance of usable liquid steel discharged from a bucket compared to metallurgical vessels with currently known designs used. in the steel industry (Buckets 1 and 2).

As will be appreciated by those skilled in the art, the precise dimensions of the cavity block reservoir of the present invention may depend on the inclination of the adjacent lower surface of the container, the overall capacity of the container, and the possible placement of geometric objects. such as, for example, the casting impact pad and the injector locations. It will be understood by those skilled in the art that the geometries of the present invention described herein describe means to improve the volumetric pouring efficiencies of metallurgical vessels. While particular embodiments of the present invention have been described for purposes of illustration, it will be apparent to those skilled in the art that numerous variations and details of the present invention may be made without departing from the present invention as defined in the appended claims.

Claims (10)

1. - A metallurgical vessel for retaining a molten metal having a slag layer thereon, comprising: a shell having a metallic exterior and an interior coated with refractory. the interior coated with refractory having sides and a sloping lower surface exposed to the interior of the container, and wherein the sloping lower surface has a tapered upper surface ending in a vertical surface, the vertical surface ending in a lower tapered surface forming a reservoir of cavity block, the cavity block reservoir having a volume of less than or equal to about five percent of the total volume of the metallurgical vessel, and wherein the cavity block reservoir includes a tap hole placed on the tapered surface lower to drain the molten metal from the metallurgical vessel.

2. The metallurgical vessel of claim 1, wherein the inclined lower surface has an angle of inclination greater than or equal to about three degrees.

3. The metallurgical vessel of claim 1, wherein the cavity block reservoir has a volume of less than or equal to about three percent of the total volume of the metallurgical vessel.

4. The metallurgical vessel of claim 1, including an impact pad placed on the inclined lower surface.

5. The metallurgical container of claim 1, wherein the pouring hole is placed there? the lower region of the cavity block deposit.

6. A method for improving the performance efficiency of a metallurgical vessel for retaining a molten metal having a slag layer thereon, comprising: employing a metallurgical vessel comprising a shell having sidewalls and a bottom to form a bottom. an interior of the metallurgical vessel for containing a molten metal; forming a refractory lining that covers the inside of the side walls and the bottom of the container wherein the refractory lining forms a sloped bottom surface exposed to the interior of the container, wherein the inclined bottom surface has a tapered top surface that terminates on a vertical surface , the vertical surface ending in a lower tapered surface to form a cavity block reservoir, the cavity block reservoir having a volume of less than or equal to about five percent of the total volume of the container, and the reservoir block cavity having a pouring hole having an opening positioned in the lower tapered surface to provide drainage of the container, wherein the pouring hole having a removable casting cover element in juxtaposition to the pouring hole to open and close the opening of the casting hole; placing the removable pour hole cover element in the closed position below the pour hole opening; placing the molten metal in the container and allowing sufficient volume for a layer of slag on the molten metal within the container for the formation of a molten metal and slag interface; draining the container by moving the casting hole removable cover element in the open position to allow the molten metal inside the container to collect in the cavity block reservoir and then pass through the pouring hole opening; and moving the casting cover removable element in the closed position simultaneously with, before or after the entry of the sscoria into the cavity block reservoir to increase the performance of the molten metal discharged from the container.

7. The method of claim 6, which includes employing the inclined lower surface having an angle of inclination of more than or equal to about three degrees.

8. The method of claim 6. which includes employing a cavity block reservoir having a volume of less than or equal to about three percent of the total volume of the container.

9. The method of claim 6, which includes placing the positioning hole in a lower region of the cavity block reservoir.

10. The method of claim 6. which includes placing an impact pad on the inclined bottom surface. SUMMARY OF THE INVENTION A metallurgical vessel having a sloping bottom surface including a tapered top surface ending in a vertical surface is described, wherein the vertical surface ends in a lower tapered surface to form a cavity block reservoir such that the block reservoir The cavity has a volume of less than or equal to about five percent of the total volume of the metallurgical vessel. This cavity block deposit provides an area for metal accumulation of waste and slag when the metallurgical vessel is discharged, thereby, resulting in a significant increase in the amount of usable pure metal discharged from the metallurgical vessel and contributing this way to improved volumetric efficiency of the container. A method is also provided to improve the efficiency of performance in the production of metal using this container.