US3511421A - Stopper and nozzle construction for metal ladles - Google Patents

Description

May 12, 1970 w. H. SMITH 3,511,421

STOPPER AND NOZZLE'CONSTRUCTION FOR METAL LADLES Filed April 29, 1968 4 Sheets-Sheet 1 INVE NTOR WILLIAM H. SMITH BY %m,zzown wu ATTORNEYS w. H. SMITH 3,511,421

4 Sheets-Sheet 2 May 12, 1970 S'I'OPPER AND NOZZLE CONSTRUCTION FOR METAL LADLES Filed April 29, 1968 WILLIAM H SMITH FIG. 2

ATTORNEYS United States Patent 3,511,421 STOPPER AND NOZZLE CONSTRUCTION FOR METAL LADLES William H. Smith,, Lansing, Ill. (163 Orchard Drive, McMurray, Pa. 15317) Continuation-impart of application Ser. No. 569,954, Aug. 3, 1966. This application Apr. 29, 1968, Ser. No.

Int. Cl. B65d 47/00 U.S. Cl. 222-559 9 Claims ABSTRACT OF THE DISCLOSURE This application is a continuation-in-part of my prior copending application, Ser. No. 569,954, filed Aug. 3, 1966, now abandoned.

The present invention is directed to new and useful improvements in teeming facilities for molten metal such as are represented by the teeming ladles commonly utilized by the steel industry.

For many years, it has been common practice in the steel industry to utilize stopper rods for controlling the flow of molten metal from the bottom of a ladle. The stopper rod is customarily provided with a head which seats upon a refractory nozzle which is inserted in the bottom of the ladle. The stopper rods have a length which is equal to or exceeds the height of the ladle itself and hence may range from something on the order of 10 feet to 20 feet or even more. These rods are supported in cantilever style over the top of the ladle and are reciprocated by a slide mechanism attached to the side of the ladle so as to open and close the nozzle orifice in the bottom of the ladle. These rods are, of course, immersed in the molten metal during use and hence these rods have customarily been fabricated from an elongated steel rod which is threaded or otherwise affixed to a refractory stopper head and then lined with refractory sleeves throughout the length of the rod. The sleeves which surround the rod are bonded together with a high temperature mortar and thus protect the steel inner supporting rod from the extreme heat of the molten metal. Careful workmanship is required in properly seating these stopper rods in position before the ladle receives its charge of molten metal and the supporting mechanism for the rod must be set with caution to insure that the stopper closes the nozzle orifice in the bottom of the ladle. Careful workmanship is also required in assembling the linear steel rod with its bottom stopper head and protective refractory sleeves since if the refractory sleeves break or the bond is not proper, the high temperature of the molten metal may reach and melt the stopper rod with the result that the rod itself becomes inoperative. After being subjected to the high temperatures involved in the use of these stopper rods, the protective refractory sleeves are usually eroded and charred so badly that they cannot be used for a second ladling operation. The inner steel rods themselves are usually badly warped from the heat and stresses involved in the teeming operation and for these reasons it has been generally customary to make up an entirely new stopper rod assembly for each pour of the ladle. In other words, after a ladle has been completely poured, the stopper rod used with the pour is removed, the refractory sleeves are stripped from the steel rod, the stopper head is removed, the steel rod is straightened and rethreaded, and then a new stopper head, and series of protective refractory sleeves are mounted on the rod for a subsequent teeming operation. Also a new nozzle is customarily provided. Considerable expense is involved in the manufacture and use of stopper rods of this type. Some workers in the industry have proposed other forms of controlling the flow of metal from the ladle by avoiding a stopper rod within the ladle and by controlling through the bottom and the ladle as in U.S. Pats. Nos. 2,268,482, 2,863,189, and 2,921,351, but for some reason or another these variant nozzle controls have not gone into commercial use or any consequence to applicants knowledge and the prevailing practice today is through use of the elongated stopper rods as aforementioned.

With the foregoing in mind, the major purposes of the present invention are to provide a novel stopper and nozzle construction for teeming ladles which may be conveniently assembled from the bottom of the ladle, to provide a stopper and nozzle assembly in which the actuating rod for the stopper is protected from the contents of the ladle except during the time that the metal is being poured, to so arrange a nozzle and stopper assembly that the operating arm or linkage for the stopper is protected from the flow of metal during the pouring operation, to simplfy the working operations necessary for use of a stopper and nozzle asembly and consequently to reduce the attendant expense in connection therewith, to provide an improved stopper head and operating rod connection therefor, all while insuring proper flow control of metal through the throat of the nozzle, these and other purposes of the invention being more apparent in the course of the ensuing specification and claims when taken with the accompanying drawings, in which:

FIG. 1 is a diagrammatic side elevation of a typical ladle provided with the improved stopper and nozzle facilities of the present invention;

FIG. 2 is a sectional view of the stopper and nozzle assembly utilized with a ladle of the form illustrated in FIG. 1;

FIG. 3 is a sectional view of a portion of the stopper assembly illustrated in FIG. 2;

FIG. 4 is a sectional view of a portion of the assembly illustrated in FIG. 2 and looking in the direction of the arrows 44 of FIG. 2;

7 FIG. 5 is a sectional view illustrating a modified form of stopper and nozzle configuration utilizable in the general fashion illustrated in FIG. 2;

FIG. 6 is a sectional view of a further embodiment of the invention;

FIG. 7 is an illustration of an adjustable mechanism which may be utilized adjustably to support certain elements illustrated in FIG. 1;

FIG. 8 is a sectional illustration of a modified form of the invention;

FIG. 9 is a top view of a lower stopper head utilized in the construction of FIG. 8;

FIG. 10 is a cross-sectional view of the nozzle of FIG. 8 taken on the lines 10-10 of FIG. 8; and

FIG. 11 is a vertical cross-sectional view of the nozzle illustrated in FIG. 8 and taken on the section lines 1111 of FIG. 8, while omitting the showing of the connection between the operating arm and the stopper rod and while illustrating movement of the stopper assembly toward open position.

Like elements are designated by like characters throughout the specification and drawings.

With specific reference now to the drawings and in the first instance to FIG. 1, the numeral 10 generally designates a teeming ladle which receives molten metal and which is adapted to pour the same through a bottom nozzle which is generally designated at 11. A stopper assembly generally designated at 12 is adapted to open and close the nozzle opening. A suitable slide mechanism, which is diagrammatically represented by a fluid cylinder 13, is mounted on the side of the ladle and is connected to a gooseneck arm 14 so as to cause vertical reciprocation of the stopper assembly 12 in response to reciprocation of cylinder 13. It should be understood that a slide mechanism may be provided by connecting cylinder 13 to a suitable reciprocating slide which is held for sliding movement in guides mounted on the ladle to thereby reduce bearing strains on the piston rod and piston within the cylinder 13. The slide mechanism may have an adjustable mounting as represented by the turnbuckle 13a in FIG. 7 in order to accurately adjust the vertical axis of the stopper relative to the nozzle 11 and the disposition of arm 14 relative to a horizontal plane.

As is seen more particularly in FIG. 2, ladle 10 is formed with the usual and customary brick working lining 15 and a brick safety lining 1'6, 17 generally designates the metallic shell of the ladle. A refractory pocket block 18 is seated in a recess in the brick working lining and safety lining in accordance with customary practice. The pocket block 18 has a central circular opening defined by a generally cylindrical wall 19. A refractory nozzle 20 is seated in this opening and is bonded to the wall 19 thereof as by means of high temperature mortar 21 in accordance with usual practices. Nozzle 20 may be supported in position by means of a retaining ring 22 which is supported on the lower face of the shell 17 by means of depending lugs 23 and keys 24 or through other suitable means. Retaining ring 22 is circular in form and underlies a shoulder 25 which is formed on the exterior lower wall of the nozzle 20.

Nozzle 20 has a central circular throat or nozzle orifice defined by an inner wall 26 which is of a generally frustoconic form and which increases in cross-sectional area from the top thereof to the bottom thereof. The wall 26 of the nozzle 20 blends into an upper wall 27 which has a curvature which is convex in cross-section and which extends circularly around the throat of the nozzle in the manner illustrated. The curvilinear surface 27 provides a seat for a stopper head 28 which has a lower generally spherically formed curvilinear surface 29 which is adapted to seat upon the wall 27 in a generally circular line contact extending around the throat of the nozzle so as to close the same to molten metal carried within the ladle 10. It should be understood that the precise configuration of the stopper surface 29 and the wall surface 27 may be varied to suit the desires of particular operators. In some cases, for example, an operator may prefer a stopper seat which is generally concave in curvature instead of convex as shown.

The stopper head 28 is preferably formed with a recess in the top surface thereof and with an aperture 31 of smaller diameter than the recess formed through the lower portion thereof. The recess provides a shoulder 32 at the bottom thereof, which shoulder provides a supporting surface for a generally cylindrical and enlarged head 33 of a steel supporting rod 34. Head 33 is securely clamped within the stopper head 28 by means of a refractory insert 34 which is screw-threaded into the walls of the recess 30 at the upper portion thereof and which bears against the upper surface of the head 33 of the rod 34.

Rod 34 is protected by a refractory sleeve 35 which surrounds the rod and which extends from the base of the stopper head 28 to a lower stopper head 36. The protective sleeve 35 may be made in plural cylindrical sections although it is preferred to make the sleeve as a single section if possible. The lower stopper head 36 surrounds the lower portion of rod 34 and has a generally semicylindrical shape on one side of rod 34 while having a different shape on the other side of rod 34. For example, the stopper head 36 has a generally semicylindrical shape designated at 37 which shape matches the cylindrical shape of the protective liner 35 on that side of the axis of the rod. On the other side of the axis, the shape ofthe stopper head 36 is composed of generally vertically extending side walls 38 and 39 as is seen more particularly in FIG. 3 and which extend laterally for a distance sufficient to underlie the lower face of nozzle 20. The upper surface of this portion of the lower stopper head is preferably given a convex curvature as designated at 40, which curvature extends from one of the side surfaces 38 to the other side surface 39. The surface 40 is adapted for abutting contact with a lower downwardly facing convex surface 41 on the nozzle. Surface 41 merges with the wall 26 defining the throat of the nozzle orifice.

The upper stopper head 28 and lower stopper head 36 may be formed from heat and erosion resistant refractory materials such as those having a high percentage of silicon carbide with some clays and other materials therein, which materials are known in the manufacture of other forms of stopper heads for ladle nozzles. The protective liner 35 may be formed from the same material, although, if high resistance to erosion and temperature is not so critical, the cylindrical liner may be formed from less expensive refractory clays. The same is true with respect to the formation of nozzle 20. The cylindrical liner 35 is bonded to the. lower surface of stopper head 28 and the upper surface of stopper head 36 as by means of a high temperature mortar which are known for bonding purposes in the industry.

The lower end of the rod 34 is screw-threaded and is attached to the operating gooseneck 14 by means of nuts 41 and 42 'which embrace opposite sides of a U- shaped end 43 of the gooseneck arm 14. The undersurface of the lower stopper head 36 is recessed to accommodate the gooseneck arm 14 as well as to accommodate the nuts 41 and 42 in the manner illustrated in FIG. 2. The upper nut 41 may bear against a washer 44 which in turn is seated against a shoulder 45 surrounding the opening for rod 34.

A protective refractory element 45 overlies the gooseneck 14 and is undercut as at 46 so as to fit within the lower stopper head 36. Element 45 may have an inverted U-shape as is seen in FIG. 4 and is bonded to the stopper head 36 at the juncture therewith.

The lower curvilinear surface 41 of the nozzle may be made of a different shape than that illustrated in FIG. 2. In FIG. 5, for example, the lower stopper head 36 is shown with relation to a concave lower surface 47 of nozzle 20 so as to provide a greater area of wall to wall contact when the stopper head 36 seats against this surface of the nozzle.

In some cases, it may be desirable to provide some protective shroud or the like around the operating stem for the stopper. For example, in FIG. 6, I diagrammatically illustrate a generally cylindrical shroud 47 which is affixed to and carried by the operating arm for the st0pper assembly. Shroud 47 may be positioned so that its upper end enters into a cylindrical groove 48 in a depending cylinder sleeve 49 which may be formed as a part of the retaining ring 50 on separately formed and attached to the retaining ring 50 for the nozzle 20.

In using the principles of the invention, a stopper assembly as illustrated may be formed and fitted with a nozzle 20 as illustrated and then the stopper assembly and nozzle may be unitarily inserted within the recess in the pocket block 18. The nozzle 20 may then be coated with cement and then cemented to the wall of the pocket block. The retaining ring 22 is then'fixed in position.

The stopper heads 28, 36 and protective sleeve 35 are preassembled with the steel rod 34 and cementer together and held under compression as by means of nut 41. With the stopper in the position illustrated and supported on the nozzle 20, the gooseneck 14 may then be fixed to the lower end of the rod 34 so that the operating slide mechanism for the stopper is connected for the opening and closing operation of the stopper. The protective element 45 may then be fixed in position over the gooseneck 14. As an alternative, the gooseneck arm may be preassembled with the rod 34 and with the protective element 45 and unitarily positioned in proper relation to the ladle with the positioning of the stopper and nozzle in the ladle.

After the nozzle and stopper are fixed in position, connected to the slide mechanism, and adjusted to a proper setting position by bracket 13a, the ladle may be filled with molten metal and then moved to a position for selective discharge of the metal. Upon reciprocation of the slide mechanism so as to raise the gooseneck 14, the stopper is elevated from the seat 27 to the position illustrated in dotted outline in FIG. 2. Metal then may flow into the throat of the nozzle and downwardly therethrough. When the stopper is in the raised position, the lower stopper head 36 abuts the surface 31 of the nozzle so as to close off the throat of the nozzle at points overlying the gooseneck 14 and for an area occupying a width equivalent to the width of the lower stopper head 36. Metal then is constrained to flow in the partially circular or annular area designated at A in FIG. 3. In other words, the flow area extends around the protective liner 35 to the side walls 38 and 39 of the lower stopper head. Thus, the gooseneck arm is adequately protected from the flow of and intense heat of the metal as being discharged. Some discharge of metal will, of course, occur above the lower stopper head 36 and between the area defined by the side walls 38 and 39 when the stopper initially moves towards the closed position, but this flow of metal is relatively small and insignificant in so far as damaging the assembly is concerned. The area of discharge may be varied to suit the individual users requirement simply by varying the diameter of the throat in the nozzle with relation to the diameter of liner 35, with or without some variance in the diameter of the nozzle receiving opening 19 of the pocket block.

Through use of a nozzle and stopper assembly as thus described, much shorter metal rods are required than in the stoppers customarily used in the industry. Also the major portion of the stopper rod itself is not subjected to the intense heat of the metal in the ladle except during the time that the metal is actually flowing through the nozzle throat. This tends to prolong the useful life of the steel rod.

The assembly utilizes a much lesser degree of ceramic protective material than is necessary with stopper rod constructions currently employed in the industry. The protective material along with the stopper heads are easily fitted to the supporting steel rod simply by inserting the steel rod 34 through the opening 31 in head 28 and then screwing the protective refractory plug 34 into its clamping position as illustrated in FIG. 2. The protective sleeve or sleeves and lower stopper are then moved over the rod 34 and cemented in place.

Through preassembly of the stopper rod and nozzle prior to installation in the pocket block, it is possible to accurately check the fit of the stopper head 28 and the seat 27 of the nozzle to insure a proper closing fit therebetween. This is easily accomplished outside of a ladle and the assembly may then be installed in the ladle even though the ladle is sufiiciently hot from a previous teeming operation as to substantially preclude working within the ladle itself.

After the ladle has been completely emptied of molten metal, the gooseneck 14 is disconnected from rod 34 and the stopper and nozzle 20 are removed from the ladle. Gooseneck arm 14 may be swung out of the way through use of the adjusting mechanism represented by bracket 13a. The rod 34 may be reused through use of new and additional protective sleeves and heads and preassembled with another nozzle 20.

FIGS. 8-11 illustrate a modified form of the invention utilizing upper and lower stopper heads and stopper seats. In FIGS. 8-11 the upper stopper head 28, the metal operating rod 34 and surrounding refractory sleeves, operating arm 14 and its connection with operating rod 34, and the refractory elements overlying and protecting the operating arm 14 are made as in the preceding FIGS. 1-7.

In FIGS. 8-11, however, the nozzle 52 and lower stopper head are shaped with different configurations so as to enable a solid circular or other shape of stream issuing from the ladle. In FIGS. 8-11, for example, the nozzle is extended substantially below the ladle, although it is held in place by a retaining ring 22 of the same type as the retaining rings of FIGS. l-7. The nozzle is extended below the ladle sufiiciently far that the lower stopper head 53 is positioned entirely within the confines of the nozzle when the stopper is in the raised or teeming position, which is illustrated in FIG. 8.

The lower stopper head is generally cylindrical in form, although one side of the lower stopper head, namely the side disposed generally diametrically opposite to the operating arm 14, is given a special configuration. For example, as is seen in FIG. 9, a recess 54 is formed in the side wall and extends from the top to the bottom of the stopper head so as to define a partially circular opening for the flow of metal. The recess may have other shapes. The exterior wall of the lower stopper head is tapered with flat surfaces on opposite sides of the recess 54 as indicated at 55 and 56. This taper provides downwardly and outwardly inclined surfaces on opposite sides of the recess 54. These surfaces terminate in relatively straight edge portions 57 and 58 at the bottom of the lower stopper head.

The nozzle 52 is shaped to cooperate with the stopper head 53 in providing a solid stream through the recess 54. For example, the wall of the throat opening through the nozzle is recessed on the side thereof remote from operating arm 14 as indicated at 59. This recess is opposed to the recess 54 in the lower stopper head. The throat wall portions opposed to the beveled surfaces 55 and 56 are also tapered as at 55a and 56a so as to match the taper of the surfaces 55 and 56. The throat wall portions 55a and 56a may have an inclination to the vertical of a degree or several degrees less than the inclination of the surfaces 55 and 56 to provide neat fit while minimizing blocking the seating of the lower stopper head against its seat.

A downwardly concave recess 60 extends around the main opening through the nozzle to the area of the surfaces 55 and 56 as is seen best in FIG. 10. This recess is adapted to match the configuration of the upper portion of the stopper head 53 so as to provide a lower stopper seat. The lower portion of the nozzle opposite to the pouring side is slotted at 61 so as to receive the operating arm 14 and protective refractory sleeve which overlies the arm 14. The lowermost portion of the nozzle opening below the stopper seat 60 is slightly enlarged as indicated at 62 and as is seen best in FIG. 11. This provides a space between and around the lower portions of the lower stopper and nozzle to the area of the surfaces 55 and 56.

In the operation of the assembly in FIGS. 8-11 downward movement of the operating arm (through use of mechanism as disclosed in FIG. 1) causes the upper stopper head 28 to abut against the upper stopper seat 27 and close the opening through the nozzle. In this closed position, the lower stopper head 53 is positioned partly outside of the opening through the nozzle. Upward movement of the operating arm brings the lower stopper head 53 into engagement with the lower stopper seat 60 through an arc greater than although less than 360. When the lower stopper head 53 engages the stopper seat 60, the upper stopper is positioned as in FIG. 8 and metal may flow through the nozzle opening and pass from the nozzle in a relatively solid stream as defined generally by the shape of recesses 54 and 59. The recesses 54 and 59 confine the stream to the shape of these recesses. At this time, lower portions of the surfaces 55 and 56 are engaged with the opposed interior wall portions 55a and 56a on opposite sides of recess 52 to more or less seal this area against flow of metal.

While the invention is illustrated as used with a teeming ladle, it should be understood that it may also be used with metal pouring devices such as, for example, a tun dish used to receive metal from a ladle and to pour metal through one or more nozzles into continuous casting molds. The term ladle as used herein should be taken as meaning a metal pouring receptacle having one or more pouring nozzles of the general type described herein.

By using the features of the invention disclosed herein, it is also possible to use a ladle with a relatively shallow slope toward the outlet defined by the nozzle, thus minimizing formation of nozzle skulls or solidified metal around the nozzle opening. In this regard, ladles used with stoppers extending upwardly above the ladle often have a relatively steep slope in an area immediately around the nozzle to aid in positioning of the stopper. Such relatively steep slopes are apt to result in skulling and attendant erratic pouring and inability to open the stopper seal.

I claim:

1. A stopper assembly for a metal pouring ladle having a bottom discharge nozzle including an elongated metallic rod, said rod having an enlarged head at one end thereof, said rod extending through an aperture formed through a lower curvilinear surface of a stopper head of refractory material, said rod head being seated in abutting relation against a shoulder in said stopper head, said stopper head having a threaded opening of larger diameter than said first-named opening and formed through the upper surface thereof, said rod head being positioned in said opening, and a refractory plug threaded into said opening and bearing against the head of said rod so as to clamp the head of said rod between said plug and said shoulder, and a lower stopper head surrounding said rod while spaced from said upper stopper head, a cylindrical refractory liner surrounding said rod and extending between said heads, said lower stopper head having a recess to receive an actuating arm for said rod.

2. The structure of claim 1 wherein said lower stopper head is formed with a semicylindrical shape of a diameter matching the diameter of said liner on one side of said rod and parallel, laterally extending walls spaced apart by a distance equal to said diameter on the other side of said rod.

3. Apparatus for controlling flow from a teeming ladle for molten metal including a pouring nozzle for a nozzle aperture in a ladle, a stopper having an operating stem extending through the throat of said nozzle, an operating arm fixed to a lower portion of said stem and extending laterally therefrom, said stopper having spaced upper and lower heads formed and adapted for engagement with stopper seats at spaced points of said nozzle, said upper head being formed and adapted for a full 360 engagement entirely around the upper stopper seat, said lower head being formed and adapted for an engagement less than 360 with said lower seat and overlying an operating arm for said stem.

4. Apparatus for controlling flow from a teeming ladle for molten metal including a pouring nozzle for a nozzle aperture in a ladle, a stopper having an operating stem extending through the throat of said nozzle and outwardly of said nozzle, said stopper having a head formed and adapted for engagement with a stopper seat on said nozzle within said ladle, an operating arm connected to a lower portion of said stem and extending laterally therefrom at a location exterior to said ladle, means for operating said arm to cause reciprocation of said stem to thereby open and close the opening through said nozzle, and lower stopper means for directing fiow of metal away from the area over said arm when said stopper is in the open position.

5. The structure of claim 4 characterized by and including a sleeve fixed to the exterior to said ladle and surrounding said nozzle and a sleeve carried by said operating arm and having a portion reciprocably received within a groove within said first-named sleeve.

6. The structure of claim 4 wherein said nozzle extends beneath the ladle and said means for directing flow of metal includes a lower stopper on said operating stern and engageable with a stopper seat positioned within the throat of said nozzle and extending partially around the throat of the nozzle.

7. The structure of claim 6 wherein said lower stopper head and throat of the nozzle are shaped to provide a discharge opening at the side of the nozzle throat opposite to the operating arm and within that portion of the nozzle throat not closed by said lower stopper seat and stopper.

8. The structure of claim 7 wherein said nozzle has a slotted portion receiving said operating arm when said operating arm is in the open position.

9. The structure of claim 8 wherein said lower stopper head includes a downwardly and outwardly inclined tapered surface on the side thereof remote from said operating arm, and a recess is formed in said surface from the top of the stopper head to the bottom thereof to define a discharge opening, said nozzle having a recess opposed to said stopper recess and a tapered surface opposed to said stopper tapered surface.

References Cited UNITED STATES PATENTS 2,587,110 2/1952 Carter 222-559 X 2,863,189 12/1958 Beck 26638 X 2,962,779 12/1960 Hornak et a1. 26638 X SAMUEL F. COLEMAN, Primary Examiner US. Cl. X.R. 266-38

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