[0001] This application claims priority to and the benefit of United States Provisional Patent Application No. 61/840, 115 filed June 27, 2013, the contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The invention relates to metallurgical vessels with hinged lids. BACKGROUND OF THE INVENTION

[0003] In a typical steel making installation, molten steel is tapped into ladles from a large steel making vessel. A typical ladle may be approximately 18 feet high, and from 10 to 12 feet in diameter at its top. Normally, a ladle is supported and transported on a ladle transfer car which runs on tracks along a path which takes it under the steel making vessel where molten steel is tapped from the bottom of the steel making vessel into the open top of the ladle. Once it is filled with molten steel, the ladle is transported from under the steel making vessel to various metallurgical treatment stations, and ultimately a teeming location, where the molten steel is tapped from a hole in the bottom of the ladle into continuous casting equipment or a mold for casting ingots.

[0004] It is known to provide ladles with insulating lids in order to provide better heat retention, reduce slag solidification and build up, and improve refractory life, among other benefits. The lid must be removed before the ladle is moved into position under the steel making vessel for tapping, and is then replaced once the filled ladle is removed from under the steel making vessel.

[0005] The lid is typically lifted from the ladle by a lifting assembly located close to the steel making vessel. The lifting assembly may include fingers, hooks or arms which engage lifting pins on the lid of the ladle. Examples of known lids and lifting assemblies are disclosed in US Patent No. 4,834,346 (Heyer et al.) and US Patent No. 8,262,982 (Leng et al.), and the patents to Heyer et al. and Leng et al. are hereby incorporated by reference in their entireties.

[0006] During the ladle filling and tapping operations, the ladle remains in an upright, vertical position. However, for periodic discharge of slag, and for ladle maintenance, inspection and cleaning, it is necessary to tip the ladle to a horizontal position and/or to a substantially inverted position. During the tilting of the ladle, the lid remains attached to the ladle but pivots away from the brim of the ladle to permit the contents of the ladle to be discharged and/or to permit access to the interior of the ladle.

[0007] The lid has a bottom layer comprised of refractory materials which can be eroded by contact with any high temperature materials such as molten metal or slag within the ladle. In order to minimize contact with the contents of the ladle, the lid is hinged to the ladle such that it will begin to open away from the brim of the ladle before the contents of the ladle flow to the brim. To accomplish this, the h inged pins about which the lid rotates are positioned above the plane of the brim, such that forward tilting of the ladle toward the horizontal orientation will result in opening of the lid.

[0008] One problem with ladles with conventional hinged lids, such as those disclosed by Heyer et al. and Leng et al., is that the hinge brackets on which the hinge pins are carried extend above the brim of the ladle. Accordingly, in some installations, where there is low clearance between the ladle and the bottom of the steel making vessel(s), metallurgical treatment station(s), or building structure(s), the hinged brackets on the ladle may interfere with said components. Another problem that exists with ladles with conventional hinged lids is that the solidification of slag on the brim of the ladle as a result of pouring and/or tapping of the steel making vessel, can interfere with complete closing of the lid. This can alter the positions of the lift pins on the top of the lid, and prevent proper engagement of the lift pins by the lifting assembly.

[0009] In view of the above-mentioned problems, there is a need for improved ladles with hinged lids.

SUMMARY OF THE INVENTION

[0010] In an embodiment, there is provided a lid for a metallurgical vessel, comprising : an upper layer having an upper surface, and a lower layer comprised of refractory materials; a front end and a rear end, with a first axis extending between the front and rear ends; the lid being segmented along a second axis into a front segment and a rear segment, the second axis being located between the front and rear ends of the lid; the rear segment having means for connecting the lid to the metallurgical vessel, said means being located proximate to the rear end of the lid; at least one hinge means connecting the front and rear segments together along the second axis, wherein the at least one hinge means includes a pivot axis about which the front segment is pivotable away from the rear segment; wherein the pivot axis is located above the upper surface of the lid.

[0011] In another embodiment, there is provided, in combination, a metallurgical vessel and a hinged lid . The metallurgical vessel comprises a hollow body with an open top surrounded by a brim, the brim having a rear edge and a front edge, wherein the front edge comprises a pouring lip of the vessel. The hinged lid is adapted to close the top of the body by sitting on the brim, and comprises an upper layer having an upper surface, a lower layer comprised of refractory materials, a front end and a rear end, with a first axis extending between the front and rear ends, the front end of the lid being located at the front edge of the brim, and the rear end of the lid being located at the rear edge of the brim . The lid is segmented along a second axis into a front segment and a rear segment, the second axis being located between the front and rear ends of the lid.

[0012] At least one segment pivoting hinge means connects the front and rear segments together along the second axis, wherein the at least one segment pivoting hinge means includes a segment pivot axis about which the front segment is pivotable away from the rear segment; and the segment pivot axis is located above the upper surface of the lid.

[0013] The rear segment of the lid is connected to the vessel by at least one lid pivoting hinge means, wherein the at least one lid pivoting hinge means includes a lid pivot axis about which the lid is pivotable away from the brim of the vessel.

[0014] In another embodiment, there is provided a lid for a metallurgical vessel, comprising : an upper layer having an upper surface, and a lower layer comprised of refractory materials; a front end and a rear end; means for connecting the lid to the metallurgical vessel, said means being located proximate to the rear end of the lid; wherein the means for connecting the lid to the metallurgical vessel comprises at least one lid pivoting hinge for pivoting the lid about a pivot axis which is located rearwardly of the rear end of the lid, and wherein each said lid pivoting hinge includes a hinge bracket extending rearwardly from the rear end of the lid to the rear pivot axis; and wherein the hinge bracket extends rearwardly and downwardly from the rear end of the lid, such that the pivot axis is located in a plane below the ladle brim .

[0015] In another embodiment, there is provided, in combination, a metallurgical vessel and a lid; wherein the metallurgical vessel comprises a hollow body with an open top surrounded by a brim, the brim having a rear edge and a front edge, wherein the front edge comprises a pouring lip of the vessel; wherein the lid is adapted to at least partially close the top of the body by sitting on the brim; wherein the lid comprises an upper layer having an upper surface, a lower layer comprised of refractory materials, a front end and a rear end, with the rear end of the lid being located at the rear edge of the brim; wherein the rear end of the lid is connected to the vessel by at least one lid pivoting hinge means, wherein the at least one lid pivoting hinge means includes a lid pivot axis about which the lid is pivotable away from the brim of the vessel; wherein the lid pivot axis is spaced rearwardly from the rear end of the lid and the rear edge of the brim; and wherein the lid pivot axis is located in a plane which is below a plane in which the brim is located.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The invention will now be described, by way of example only, with reference to the accompanying drawings, in which :

[0017] Figure 1 shows a metallurgical vessel with a hinged lid according to a first embodiment of the invention, with the vessel in an upright, vertical orientation and with the lid closed;

[0018] Figure 2 shows the metallurgical vessel of Figure 1 having been forwardly tilted unto a horizontal orientation, and with the forward segment of the lid pivoted away from the rear segment of the lid and the brim of the vessel;

[0019] Figure 3 shows the metallurgical vessel of Figure 1 having been forwardly tilted past the horizontal orientation to an inverted orientation, and with the rear and forward segments of the lid pivoted away from the brim of the vessel;

[0020] Figure 4 shows a metallurgical vessel of Figure 1, showing a displacement of the forward segment caused by solidified (frozen) slag on the front edge of the vessel brim, and also showing a portion of the lifting assembly engaging lift pins on the top of the lid; [0021] Figure 5 shows a metallurgical vessel with a hinged lid according to a second embodiment of the invention, with the vessel in an upright, vertical orientation and with the lid closed;

[0022] Figure 6 shows the metallurgical vessel of Figure 5, having been forwardly tilted unto a horizontal orientation, and with the forward segment of the lid pivoted away from the middle segment of the lid and the brim of the vessel; and

[0023] Figure 7 shows a metallurgical vessel with a hinged lid according to a third embodiment of the invention, with the vessel in an upright, vertical orientation and with the lid closed.

DETAILED DESCRIPTION

[0024] A ladle 10 according to first embodiment of the invention is illustrated in Figures 1 to 4, with all unnecessary detail being omitted for clarity. The ladle 10 is generally of conventional construction, and comprises a hollow cup-like body 12 of frusto-conical configuration with a substantially flat bottom 14, and a brim 16. The body 12 of ladle 10 is provided with a pair of

diametrically opposed trunnion pins 18. The common axis of the trunnion pins 18 is located slightly above the center of gravity of the ladle 10 when empty, such that the ladle 10 can be suspended and tipped to remove slag, for example as illustrated in Figures 2 and 3.

[0025] The ladle 10 has a front edge 20 which forms a pouring lip of the ladle 10. The ladle also includes a rear edge 22, provided with a pair of hinge brackets 24, each carrying a hinge pin 25, for connection to a lid 26.

[0026] The lid 26 is adapted to close the top of the body 12 of ladle 10 by sitting on the brim 16. Although the drawings provide little detail regarding the structure of lid 26, it will be appreciated that the lid may be of conventional construction, and may have an inner surface (i.e. the surface facing the interior of the ladle), comprised of refractory materials. The lid 26 may be constructed in accordance with the lids described in Heyer et al. and Leng et al.

[0027] The rear 28 of lid 26 is provided with a pair of rearwardly extending hinge brackets 30. Although not shown in the drawings, each of the hinge brackets 30 defines a downwardly opening slot adapted to receive a hinge pin 25 supported by the ladle hinge brackets 24.

[0028] As illustrated, the lid 26 is comprised of two segments, namely a rearward segment 32 and a forward segment 34, wherein the rearward segment 32 of lid 26 covers the rear portion of the ladle 10 at which the h inged connection is provided, while the forward segment 34 of lid 26 is located at the front end of the ladle 10, at which the pouring lip is provided.

[0029] As shown in the drawings, the rearward segment 32 of lid 26 may be of greater area than the forward segment 34, furthermore, the rearward segment carries the hinge brackets 30 of lid 26. The rearward segment 32 also carries the upstanding brackets 36 and pins 38 (Fig. 4) by which the lid 26 is lifted from the ladle 10 by a lifting assembly, generally indicated by numeral 46 in Fig . 4.

[0030] As shown in the drawings, the hinge brackets of the ladle 24 extend rearwardly from the rear edge 22 of ladle 10, but do not extend above the brim 16 of ladle 10. The hinge pins 25 of brackets 24 are located proximate to the rearward ends of the brackets 24, and define the pivot axis about which the lid 26 rotates. With this arrangement, once the lid is removed, there are no hinge brackets protruding above the level of the brim 16, and therefore the ladle hinge brackets 24 do not interfere with positioning of the ladle 10 below a steel making vessel.

[0031] As will be appreciated, the positioning of the ladle hinge brackets 24 and the hinge pins 25 at or below the plane of brim 16 will resu lt in the lid remaining in place on ladle 10 when the ladle is tipped to the horizontal orientation, shown in Fig. 2, and until the ladle is tipped past horizontal as shown in Fig . 3. Therefore, one may expect that location of the lid pivot axis at or below the brim 16 of ladle 10 may result in an increased risk of contact between the slag and the refractory layer of the lid 26. However, such contact is avoided by the structure of lid 26. In this regard, the forward segment 34 is connected to the rearward segment 32 by a hinged arrangement, whereby the forward segment is rotatable about a pivot axis which is located above the upper surface of lid 26. In this regard, the rearward segment 32 and forward segment 34 are provided with respective hinge brackets 40, 42, which are connected by a hinge pin 44 which defines the pivot axis of the forward segment of lid 26. Therefore, when the ladle 10 is tipped to the horizontal position for the purpose of discharging slag, as shown in Fig. 2, the forward segment 34 will begin to open away from the brim 16 of the ladle 10 before the slag flows up to the front edge 20 of brim 16. Therefore, by the time the slag reaches the brim 16, the forward segment 34 of lid 26 will have opened far enough away to avoid any contact with the hot slag .

[0032] As mentioned above, due to the ladle pouring and/or the tapping of the steel making vessel, solidified slag has a tendency to build up along the front edge 20 of brim 16, as shown in Fig. 4. This may affect the position of the forward segment 34 of lid 26 when in the closed position, with the ladle 10 in an upright position. However, any misalignment of the forward segment 34 of lid 26 caused by the build up of material adjacent to the front edge, will not have any effect on the positioning of the rearward segment 32 of the lid 26. Since the rearward segment 32 carries the upstanding brackets 36 and pins 38 which engage the lifting assembly 46, the alignment of lid 26 with the lifting assembly will not be affected by any build up of material along the front edge 20 of brim 16.

[0033] A second embodiment of the invention is now described below with reference to Figures 5 and 6, showing a ladle 110 according to a second embodiment of the invention. The ladle 110 is similar in structure to ladle 10 described above, having a body 112, having a bottom 114 and a brim 116. The ladle 110 according to the second embodiment has a pair of pouring spouts, including a rear pouring spout 118 located along a rear edge of the brim 116, and a front pouring spout 120 located along a forward edge of the brim 116. In other words, the ladle 110 is configured to pour from one of the opposing spouts 118, 120 when tilted forwardly or rearwardly.

[0034] The ladle 110 includes a segmented lid 122 having a stationary central segment 124, a pivotable rear segment 126 adapted to cover the rear pouring spout 118, and a pivotable forward segment 128 adapted to cover the front pouring spout 120.

[0035] Hinged connections are provided between the central segment 124 of lid 122 and each of the rear segment 126 and forward segment 128. Each of these hinged connections comprises a pair of hinge brackets 130, 132 and a hinge pin 134 defining the pivot axis. As shown in the drawings, the pivot axis is located above the brim 116, so that, when the ladle 110 is tilted either rearwardly or forwardly for the purpose of discharging slag (or otherwise), one of the segments 126, 128 will pivot away from the brim 116, to allow slag (or otherwise) to be poured from the ladle 110.

[0036] Illustrated in Figure 7 is a third embodiment of the invention, comprising a ladle 210 which is similar in structure to ladle 10 described above, and in which like elements are identified by like reference numerals. As in the first embodiment, ladle 210 has a body 12 with a bottom 14 and a brim 16. The ladle 210 has a front edge 20 which forms a pouring lip and a rear edge 22, provided with a pair of hinge brackets 24, each carrying a hinge pin 25, for connection to a lid 232, which may be equivalent to the rearward segment 32 of lid 26 in Figures 1-4. As shown, the lid 232 of Figure 7 only partially covers the open top of the ladle 210, and leaves an opening in the vicinity of the front edge 20 through which the contents of the ladle 210 can be poured without opening of lid 232 away from the brim 16.

[0037] Therefore, the lid of ladle 210 does not include a forward segment 34 such as that shown in Figure 1-4, nor does it include the hinge brackets 40, 42 or the hinge pin 44 by which the forward segment 34 of lid 26 is connected to the rearward segment in the embodiment shown in Figures 1-4. Thus, the embodiment of Figure 7 provides a simpler design which may be used in applications where it is acceptable to not completely cover the contents of the ladle 210.

[0038] In order to empty the ladle 210 of its contents, it can be tilted unto the horizontal orientation as shown in Figure 2, which will cause the contents of ladle 210 to be discharged through the opening at the front edge 20. Further tilting of the ladle past horizontal as shown in Figure 3 will eventually resu lt in the partial lid 232 pivoting away from the body 12, increasing the area of the discharge opening.

[0039] Due to the lack of a forward lid segment 34, the embodiment of

Figure 7 avoids any issues with displacement and / or sticking of the forward segment 34 caused by contact with slag on the front edge 20 of the vessel brim 16, as shown in Figure 4, while also avoiding any contact between the slag and the refractory layer of the lid 232 as the slag is poured from the ladle 210.

[0040] Although the invention has been described in connection with certain embodiments disclosed herein and shown in the drawings, it is not intended to be limited thereto. Rather, the invention is intended to include all embodiments which may fall within the scope of the following claims.