US3511471A - Ladle stopper - Google Patents

Description

May112, 1970' 'f" 1. @0551 3,511,471

LADLE [STOPPER I FiledJan. 19, 1968 s SheetS -Sheet 1 FIG! INVENTOR. IRVING ROSSI BY j Z M Mam/M ATTORNEYS 3,511,471 LADLE STOPPER Irving Rossi, Morristown, N.J., assignor to Concast, Inc., New York, N.Y. Filed Jan. 19, 1968, Ser. No. 699,265 Int. Cl. F16k /00, 5 /22 U.S. Cl. 251-144 6 Claims ABSTRACT OF THE DISCLOSURE The present invention relates generally to ladles, or other vessels, for molten metal and particularly to stoppers for the outlet openings of such vessels.

Stoppers for ladles, or other vessels of the type under consideration, are usually steel rods covered with refractory sleeves, such as fireclay, that are supprted vertically in the vessels with their lower ends adapted to seat in outlet openings through the bottoms of the vessels and are raised and lowered to open and close the outlet. In operation they are subjected to severe physical and thermal shock and their lower ends rapidly become chipped and worn, permitting leakage. Also the refractory sleeves erode rapidly exposing the core rod at the slack line of molten metal in the vessel. Consequently, these stopper rods must usually be replaced after each heat, which is expensive.

It has been proposed to mount a sliding plate on the underside of the vessel for closing and opening the outlet, but these sliding gates have not been satisfactory. They must be finely ground and closely fitted to the surface of the vessel across which they are adapted to slide; otherwise molten metal leaks out around them. In addition, metal tends to stick to the portion of the gate over the outlet opening in closed position and prevents or impedes sliding of the gate to open the outlet.

It is therefore an object of the present invention to provide a stopper which does not have these drawbacks. Specifically, it is an object to provide a stopper that is effective for closing and opening the outlet without excessive wear, so as to provide a stopper which need not be replaced as often as the rod type.

Another object is to provide a sliding stopper that can be opened without having to apply excessive force even if metal sticks to the portion of the stopper which covers the outlet in its closed position.

A stopper in accordance with this invention comprises generally a block of refractory material rotatively supported with one surface in contact with the outside surface of the vessel around the circumference of the outlet opening in the vessel. The block has an open-ended passage with one end of the passage through the surface of the block in contact with the vessel and arranged to coincide with the outlet opening of the vessel in one position of rotation of the block. When the block is rotated to another position another portion of said surface is United States Patent 0 over the outlet opening and closes it. The walls of the ables the block to be moved to open position, even if some metal sticks to the portion over the outlet opening of the vessel, without having to apply a great deal of extra force to shear the sticking metal off the gate.

Further objects and advantages of this invention will be apparent in the following detailed description of examples of stoppers which embody the features of the invention and which are illustrated in the accompanying drawings wherein:

FIG. 1 is a view of a vertical section through the outlet opening in the bottom of a vessel illustrating one form of stopper, embodying the features of the present invention, mounted on the vessel;

FIG. 2 is a view along the line 22 of FIG. 1;

FIG. 3 is a view similar to FIG. 1, but showing another form of outlet opening in the bottom of the vessel with a second form of stopper embodying the invention;

FIG. 4 is a bottom view of the stopper shown in FIG. 3;

FIG. 5 is another view similar to FIG. 1 but showing still another form of outlet opening and a third form of stopper embodying the invention.

FIG. 6 is still another view similar to FIG. 1, but showing a fourth form of stopper embodying the invention; and

FIG. 7 is a bottom view of the stopper shown in FIG. 6.

Referring to FIGS. 1 and 2 of the drawings, a section of the bottom 10 of a vessel for molten metal is shown to illustrate the portion of the bottom which has an outlet opening 11 therethrough. The remainder of the vessel is omitted since suitable structure for ladles, and other molten-metal-containing vessels, are well known and form no part of the instant invention. Numeral 12 desigates the bottom plate of the vessel; numeral 13 designates a lining of refractory material. The outlet opening 11 is defined by a bushing 14 of refractory material through the lining in line with a hole 15 through an insert 16 of refractory material, such as graphite-alumina, which is fixed is an appropriate opening in the bottom plate 12. As seen in FIG. 2, the upper portion 17 of the insert 16, and the opening in which it is fixed, are shaped to resist rotation relative to the bottomfor this purpose, they may be hexagonal shape as shown. The lower portion of the insert 16 is a circular protuberance 18 with the hole 15, which forms part of the outlet opening 11, opening through the protuberance at one side (left) of the center line 19 thereof.

In accordance with the invention, the stopper for the opening 11 is provided by a block 20 of refractory material having a surface 21 in contact with the outside surface of the vessel around the circumference of the opening of the outlet 11. In this instance the outside surface of the vessel around the outlet 11 is the lower surface of the protuberance 18 and the surface 21 of the block is concavely contoured to match, and fit closely against it.

The block 20 is supported to rotate relatively around the center line 19 of the protuberance 18 so that in one position of rotation of the block a hole 23 through the block coincides with and opens the outlet opening 11, and so that when the block is rotated to another position, a portion of its surface 21 is over the outlet 11 to close it. The block 20 illustrated in FIG. 1 is shown with alternative hole 23' through another portion of the block in position to be moved into coincidence with the outlet opening 11, alternatively to the hole 23, for unstopping the outlet.

As indicated in the drawing, hole 23, and alternate hole 23, and the lower portion of the hole 15 through the protuberance 18 are preferably bevelled to flare slightly toward the outside to reduce the possibility of metal passing through the outlet 11 and hole 23 or 23 from sticking to the side walls of the outlet passage.

As shown in FIG. 1, suitable means for rotatively supporting the block 20 comprises an annular outward-projecting flange 25 around the sides of the block. This flange 25 extends over an annular flange 26, which projects inward from a flange ring 27. The flange ring 27 is suitably secured on the bottom plate 12 of the vessel by bolts 28, or other conventional fastening device. Means, such as coil springs (not shown around the bolts 28 between the bolt heads and the flange ring 27 in the manner illustrated in FIG. 6, may be provided to hold the block 20 against the insert 16 under spring pressure that is adjusted'to resist the ferrostatic pressure of metal in the vessel when the block 20 is in closed position. Such springs also provide self-regulating compensation for heat expansion of the relatively-sliding parts. A loose ring 29 (or other suitable friction-reducing means, such as ball bearings) seated in appropriate annular grooves in the opposed underside of flange 25 and upper side of flange 26 are provided to facilitate rotation of the block 20 around the flange 26.

As shown in FIG. 1, the sides and part of the bottom of block 20 are carried in, and supported by a metal basket 30, the flange 25 being the upper, outwardly-directed edge of the basket. The block 20 is fixed against independent rotation realtive to the basket by being cemented therein, by pegs or set screws (not shown) or by other conventional means. One or more lugs or handles 31 may be provided on the side of the basket 30 as means to rotate the block 20 for opening and closing the outlet 11.

Rotation of the block 20 relatively around the protuberance 18 is made easier by placing friction-reducing material at the interface between the surface 21 of the block and the surface of the protuberance 18. For example, one or both of the contacting surfaces may be provided with an overlay of a stainless steel foil, indicated at 32. Alternatively, or in addition, powdered refractory material, talc powder or other heat-resistant lubricating powder may be sprinkled on one or both contacting surfaces.

FIGS. 3 and 4 show a second form of the stopper for use with an outlet opening 11. In this form, the lower portion of the outlet opening 11 has two branches 11a and 11b, opening through the lower portion of the protuberance 18 respectively at opposite sides of the center line 19. The hole through the block 20 is provided by a hole 35 opening through the center of the block at the bottom and flaring out to provide an elongated opening through the surface 21 of the block (indicated by dash 7 lines in FIG. 4) to coincide with the branches 11a and 11b of the outlet 11 when the block is rotated to the position shown in FIGS. 3 and 4.

, FIG. illustrates a modified insert 16a, having a hole 15a in line with the outlet opening 11 of a vessel, and a third form of stopper embodying the invention. In this instance the underside of the refractory insert 16a is flush with the bottom plate -12 of the vessel and surface 21a of the block 20a, in contact therewith, is correspondingly contoured (i.e., fiat, as shown). The block 20a is suitably supported to rotate about its center by flanges 25 and 26 as described with reference to FIG. 1. The bevelled hole 23a through the block 20a is at one side of the side center line 36 and the block is placed and supported on the bottom of the vessel for its hole 23a to coincide with and open the outlet opening 11 in one position of rotation; the outlet opening 11 is covered, and thus stopped, by a portion of the block surface 21a, when the block is rotated, around center line 36 to another position.

A fourth form of stopper embodying the invention is shown in FIGS. 6 and 7. In this instance a support plate 37 is welded to the bottom plate 12 of the vessel and has a hole 38 coinciding with an appropriate opening through the bottom plate 12 for the outlet opening 11. As in the embodiments previously described the vessel has a lining 13 of refractory material and the outlet opening 11 is defined by a bushing 14 whichis also of refractory material.

The bottom of the support plate 37 is flat and the block 40 of refractory material, which provides the stopper, is mounted on a base plate 39 which in turn is removably mounted on the support plate 37. As seen in FIG. 7, the periphery of the base plate 39 is a six sided polygon, with three short sides respectively between three long sides, and at alternate three sides (the three short sides in the drawing) the edges of the base plate 39 are provided with deep square notches 43, into which blocks 44 projecting down from the support plate 37 are received when the base plate 39 is in proper position relative to the support plate 37. The blocks 44 project down below the notches and have horizontal, transverse keyways 45 through them, to receive keys 46, which are suitably wedge shaped to be carried through the keyways 45 and wedged against the bottom surfaces of the base plate 39 at opposite sides of the notches 43 for holding the base plate 39 firmly against the support plate 37.

A projection 47, outward from one edge of the base plate, has a downward-projecting block 48 and the ends of a peg 49, fixed transversely through the block by a set screw 50, extend out from opposite sides of the block. When the base plate 39 is in position on the support plate 37, the block 48 is received between a pair of ears 51 projecting down from the support plate 37 with their lower ends extending below the lower end of the block 48, and the ends of the peg 49 are received in elongated vertical slots 52 in the ears. As shown, one side of each slot 52 is open through an edge of the respective ears 51 for the ends of the peg 49 to enter the slots when the base plate 39 is positioned, and the top and bottom ends of the slots 52 are semi-circular to conform to the circumference of the peg 49. With this arrangement, when the base plate 39 is loosened by removing the keys 46, the base plate is let down until the ends of the peg 49 rest in the curved bottom ends of the slots 52 which provide a supporting pivot holding the base plate at one edge and permitting the plate to swing down to a vertical position for repair or replacement of the elements carried thereon.

The central portion of the base plate 39 has a downward-projecting annular protuberance 54 on its underside. A hole 55 through the base plate is stepped with its smaller end opening eccentrically through the protuberance. A stepped bushing 56, of refractory material and having a bore 57 therethrough, is shaped to be received in hole 55 and is held therein by a retaining ring 58 attached on the base plate, in an appropriate annular undercut portion, by bolts 59. As shown, the blocks 44 are located on the support plate 37 to position the base plate 39 with the bore 57 of bushing 56 in line with the hole 38 through the support plate 37.

The lower end of the bushing 56 projects slightly below the bottom surface of the protuberance 54 and the block 40 of refractory material, having a hole 61 eccentrically therethrough, is supported against the bottom of the bushing by an annular basket 62, in which the block 40 is carried, and which has an opening 63 through the bottom to expose the opening of hole 61 in the block 40. The block 40 may be fixed against relative rotation in the basket 62 by having a circumference other than round or by being cemented therein. The basket 62 is supported concentric to the protuberance 54 by an annular outward-turned upper edge 65 slidably supported on inward-extending annular flange 66 of a ring 67 fastened on the base plate 39 by bolts 68. through the ring threaded into the base plate. Coil springs 69 around the bolts 68. between their heads and the ring 67, urge the bushings upward to hold block 40 in basket 62 firmly against the lower end of the bushing 56. The pressure of the springs 69 is adjusted, by tightening or loosening bolts 68, so as to permit rotation of the block 40 relative to the bushing 56 but to prevent the block from being pushed down and separated from the bushing by the ferrostatic pressure of metal in the vessel bearing against the block 40 when the latter is in closed position. The springs 69 also provide compensation for heat expansion of the parts, which move relative to each other, so that they will not become bound in one position.

The ring 67 is preferably made of a low-friction material, such as bronze, to facilitate rotation of the basket 62, and hence the block 40 on flange 66; alternative or supplementary lubricating means, such as po\vdered lubricant placed at the interface between the flange 66 and the edge 65 of the basket 62, could also be used. Thus the basket 62 and block 40 are rotatable about the center line of the protuberance 54 from the open position, shown in the drawing, in which the hole 61 in the block 40 coincides with the bore 57 of the bushing 56 to open the outlet from the vessel, to closed position in which a solid portion of the block 40 is over the bottom end of the bore 57. Means, such as a handle bar 70 attached across the outward end of a block 71, which is on the bottom of the basket 62, is provided for rotating the basket and block.

What is claimed is:

1. A stopper for an outlet opening of a vessel for molten metal wherein said outlet opening is formed by an outlet passage opening through the outward end portion of a circular protuberance on said vessel at one side of the center line through said protuberance, said stopper comprising a block of refractory material having a surface concavely contoured to encompass and be in contact with the surface of said outward end portion of the protuberance, and means supporting the block for rotation relatively around said center line of the protuberance in contact with the protuberance for said surface of the block to be slid relatively across the surface of the protuberance which is around the opening of said outlet passage therethrough, said block having an open ended passage therethrough with one end opening through its said surface to coincide with the opening of the outlet passage through the protuberance in one position of rotation, whereby said outlet passage of the vessel is opened by rotating the block to said one position and closed by rotation of the block to another position.

2. The stopper of claim 1 including friction-reducing means between said contacting surfaces.

3. The stopper of claim 2 in which said friction-reducing means comprises a thin layer of metal on at least one of said contacting surfaces.

4. The stopper of claim 1 in which said protuberance projects downward and in which said means for supporting said block comprises a first annular bearing surface on a first member attached to said block, said first bearing surface being concentrically around the block and resting on a second annular bearing surface, said second bearing surface being on a second member supported on a vessel and being concentrically around the protuberance.

5. The stopper of claim 1 which includes: a plate member having an outlet passage opening therethrough and being removably attached to said vessel with said outlet passage coinciding with the outlet opening of the vessel said protuberance being on said plate with said outlet passage opening through its outward end portion at one side of its center line, said block being rotatively supported on said plate member with said surface of the block in contact with and slidable relatively across the surface of the protuberance of the plate member that surrounds the opening at the outlet passage therethrough for the passage through the block to coincide with the opening of the outlet passage through the plate member in one rotative position of the block and for the block to cover the latter opening when the block is rotated to another position, and adjustable spring means urging said contacting surfaces together for resisting separation of said surfaces by pressure of metal in the vessel and for yielding to compensate for heat expansion of said surfaces.

6. The stopper of claim 5 in which said block is rotatively supported on the plate by a first annular flange mounted concentrically on the block and having a bearing surface resting on said supported by a bearing surface of a second annular flange that is mounted on the plate member, and in which said second annular flange is mounted on the plate member by mounting means including said spring means, said spring means being arranged for urging said bearing surface of the second flange toward said bearing surface of the first flange.

References Cited UNITED STATES PATENTS 1,338,001 4/1920 Cordes 251--144 X 3,165,795 1/1965 Bahm 25 l304 X 3,377,006 4/ 1968 Bahm 222-554 X 3,386,633 6/1968 Nadrich et a1 251-144 X M. CARY NELSON, Primary Examiner W. R. CLINE, Assistant Examiner U.S. Cl. X.R.

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