US3618925A

US3618925A - Adjustable closure for outlets in receptacles for molten metal or the like

Info

Publication number: US3618925A
Application number: US11232A
Authority: US
Inventors: Bernard Girolami
Original assignee: Institut de Recherches de la Siderurgie Francaise IRSID
Current assignee: Institut de Recherches de la Siderurgie Francaise IRSID
Priority date: 1969-02-14
Filing date: 1970-02-13
Publication date: 1971-11-09
Anticipated expiration: 1988-11-09
Also published as: AT295063B; CA917915A; DE2004907C3; SE365142B; BE745754A; DE2004907B2; DE2004907A1; SU368727A3; GB1229765A; FR2031968A5

Abstract

A closure for outlets in receptacles for molten metal wherein a frame having sides which form a regular polygon accommodates a set of coplanar vanes, one for each side of the frame. The vanes comprise identical triangular portions bounded by edge faces each of which abuts against one edge face of the adjoining vane. The apices of all triangular portions abut against each other in outlet-closing positions of the vanes, and the vanes are movable from such closing positions along the respective sides of the frame, in the same direction and through identical distances, whereby their triangular portions define a polygonal passage for outflow of molten metal. The center of such passage coincides with the center of the frame.

Description

United States Patent ADJUSTABLE CLOSURE FOR OUTLETS IN RECEPTACLES FOR MOLTEN METAL OR THE LIKE 16 Claims, 7 Drawing Figs.

US. Cl 266/38, 164/136, 222/503, 222/561 Iut.Cl C2lb 7/14 Field of Search 266/38;

[56] References Cited UNITED STATES PATENTS 1 1,919,619 7/1933 Dean 222/503 3,226,768 1/1966 Von Zielewsky et a1 222/503 FOREIGN PATENTS 218,734 8/1968 U.S.S.R. 222/502 Primary Examiner-Gerald A. Dost Attorney-Michael S. Striker ABSTRACT: A closure for outlets in receptacles for molten metal wherein a frame having sides which form a regular polygon accommodates a set of coplanar vanes, one for each side of the frame. The vanes comprise identical triangular portions bounded by edge faces each of which abuts against one edge face of the adjoining vane. The apices of all triangular portions abut against each other in outlet-closing positions of the vanes, and the vanes are movable from such closing positions along the respective sides of the frame, in the same direction and through identical distances, whereby their triangular portions define a polygonal passage for outflow of molten metal. The center of such passage coincides with the center ofthe frame.

ADJUSTABLE CLOSURE FOR OUTLETS IN RECEPTACLES FOR MOLTEN METAL OR THE LIKE BACKGROUND OF THE INVENTION The present invention relates to closures for outlets in receptacles for flowable materials, particularly for molten metal, such as molten steel or iron.

Refining of metals normally necessitates treatment in liquid state including decanting of molten metal from one receptacle or vessel into another, for example, pouring of molten metal into ingot molds. The decanting is either continuous or intermittent; in each instance, the vessel from which molten metal is poured must be provided with a closure for its outlet to permit interruption of outflow and/or regulation of the rate of discharge.

Earlier types of receptacles for molten metal, for instance molten steel or iron, are provided with closure in the form of stopper rods which are movable into engagement with a seat provided therefor at the inner end of an outlet, i.e., the stopper rod must extend into the pool of molten metalin the receptacle. Such closures are unsatisfactory for many reasons, for example, when the molten metal is treated with a gas which is caused to bubble through the bath of molten material or when such material is treated in vacuo in a ladle or the like. The stopper rod is likely to be damaged or destroyed, either as a result of violent mixingof molten metal in the receptacle or on prolonged contact with molten metal.

It is also known to provide a receptacle for molten metal with a composite valve which is located externally of the receptacle at a level below and opposite the outlet orifice. Such externally mounted valve is less likely to be rapidly affected by the hot contents of the receptacle. It normally comprises two overlapping plates or blades which are provided with cylindrical bores and are pivotable or reciprocable relative to each other to place their holes into partial or full registry and to thus determine the rate of outflow. It was found that such a valve is reasonably satisfactory when its plates are moved to fully open positions in which their holes arein full registry with each other. However, when the plates are moved toward or from fully open positions, they cause turbulent outflow of molten metal and the position of the jet of issuing material varies in dependency on the extent of overlap. Also, the shifting jet causes localized wear on the refractory material of the plates with the result that the plates offer an increasing resistance to movement between open and closed positions. Therefore, the just described valve is normally used only on or with receptacles wherein the outlet is either sealed or fully exposed, i.e., such valve is not suited to change the rate of outflow during decanting of molten metal. Consequently, the valve is useless in or on vessels serving to pour molten metal into continuous ingots which should receive metal at.a variable rate.

SUMMARY OF THE INVENTION An object of the invention is-to provide a novel and improved closure for use on or with receptacles for flowable materials, particularly for molten metal, and to construct and assemble the closure in such a way that it can completely seal the outlet of a receptacle as well as that it can permit convenient, accurate and repeated adjustment of the rate of outflow.

Another object of the invention is to provide a closure which is less likely to produce turbulence in outflowing material than heretofore known closures.

A further object of the invention is to provide a closure which insures that the jet of discharged molten metal invariably flows in a desired direction, regardless of whether the closure permits flow at a maximum rate or at any rate between the minimum rate (outlet sealed) and maximum rate.

An additional object of the invention is to provide a closure which can be readily installed on or assembled with conventional receptacles for molten metal or the like.

Still another object of the invention is to provide a closure which comprises a small number of relatively simple parts,

' wherein the parts are capable of standing long periods of use,

kll

and which can be manipulated either by hand, by remote control, or by programming means.

The invention is embodied in a closure for use with a receptacle having an outlet for flowable materials, particularly for molten metal. The closure comprises at least three adjoining vanes located in a common plane and each having a triangular portion bounded by two straight edge faces meeting at an apex and making an angle of 360/n wherein n is the number of vanes. Each edge face of each triangular portion abuts against an edge face of the adjoining triangular portion and the vanes are movable in their common plane unidirectionally through equal distances at right angles to the lines dividing the respective apex angles between an outlet-closing position in which the apices of all triangular portions are adjacent to each other and a plurality of open positions in each of which the triangular portions define a polygonal passage of different cross-sectional area in registry with the outlet of thereceptacle.

Each vane preferably comprises or is connected with a carriage which is reciprocable along one of several elongated guide means forming a polygonal frame and enclosing the area which accommodates the vanes. The carriages can be connected to each other by mechanical'me'ans to insure simultaneous movement of all vanes in a clockwise or in a counterclockwise direction, through identical distances, and while the respective edge faces remain in abutment with each other. The center of the polygon defined by the guide means coincides with the point where the apices of the triangular portions meet in closed positions of the vanes. The center of the polygonal passage defined by the triangular portions in each open position of the vanes coincides with the center of the polygon so that the core of the jet of molten'metal issuing from the receptacle in open positions of the vanes does not change its location, irrespective of the extent to which the vanes are moved from their outlet-closing position.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved closure itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic front elevational view of a closure with three vanes which embodies one form of the invention and wherein the vanes are shown in outlet-closing positions;

FIG. 2 illustrates the structure of FIG. 1 but with the vanes shown in one of their open positions;

FIG. 3 is a schematic front elevational view of a closure with four vanes which are shown in outlet-closing positions;

FIG. 4 illustrates the structure of FIG. 3 but with the vanes in one of their open positions;

FIG. 5 is a front elevational view of all important details of a closure with three vanes which is mounted on a receptacle for molten metal;

FIG. 6 is a sectional view as seen in the direction of arrows from the line F-O-F of FIG. 5; and

F IG. 7 is a front elevational view of a modified closure with three vanes.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates the basic components of a closure with three identical vanes l, 2, 3, which are located in a common plane within the confines of a frame F forming an equilateral triangle. The vanes consist of refractory material and include abutting triangular inner portions la, 20, 3a whose apices meet at the center of the polygon defined by the frame F.Each of the portions 1a-3a is an isosceles triangle and is bounded by two edge faces 1b-1c, 2b-2c, 3b-3c and the edge faces 1b, 10, 2b respectively abut against the

edge faces

2c, 3b, 30. Each of the apex angles I, II, III equals 360/3=l 20.

The second or

outer portions

1d, 2d, 3d of the vanes 1-3 are of rectangular outline and are slidable along the respective portions of the frame F from the closing positions shown in FIG. 1 (in which the three apices are adjacent to each other) toward the open positions shown in FIG. 2. The directions in which the vanes l-3 are movable from the closed positions are indicated by arrows shown in FIG. 2. The frame F comprises three elongated guide means 6, 7, 8 along which the

outer portions

2d, 3d, 1d move while the respective edge faces remain in contact with each other. FIG. 2 shows the vanes in fully open positions in which the

outer portions

1d, 2d, 3d respectively abut against the guide means 6, 7, 8 and in which the triangular portions 1a-3a define a triangular passage 9 of maximum cross-sectional area. The center of this passage coincides with the center of the triangle defined by the guide means 6-8 and with the point where the apices of the portions 1a-3a meet in the positions shown in FIG. 1. Of course, the vanes 1-3 can be moved to an infinite number of intermediate open positions in each of which their portions 1a-3a define a passage of a different cross-sectional area but the center of each such passage coincides with the center of the passage 9.

The maximum distance d which the vanes 1-3 can cover during movement between the end positions shown in FIGS. 1 and 2 is less than the distance e between a corner of the polygon and the two nearest outer portions (1d, 2d or 2d, 3d or 3d, 1d) in closing positions of the vanes. Since the outer portions 1d-3d slide along the guide means 8, 6, 7 and since the edge faces of the triangular portions 1a-3a are in constant abutment with each other, movement of any one vane along the respective guide means necessarily causes equidirectional movement of the other two vanes through the same distance. In the closure of FIGS. 1 and 2, the vanes can be moved clockwise or counterclockwise. If the edge faces 1b-3c are in proper face-to-face abutment with each other, and if the outer portions ld-3d are guided with requisite accuracy, the portions 1a-3a prevent any leakage in closing positions of the vanes and they permit molten metal or other flowable material to escape only by way of the passage 9 (or a smaller passage) when the vanes are moved away from the closing positions. During movement of vanes 1-3 from the positions shown in FIG. 1 toward the positions shown in FIG. 2, the area of the passage 9 grows symmetrically about the center of the triangular area which is defined by the frame F and accommodates the vanes. This is important because the core of the jet of molten metal issuing from the receptacle whose outlet is controlled by the closure of FIGS. 1 and 2 need not change its position during movement of vanes 103 toward or away from the closing positions. Consequently, molten metal can be discharged with a minimum of turbulence and the jet of such metal can be readily directed toward a selected part of the vessel (e.g., an ingot) which is to accept the outflowing material.

FIG. 3 illustrates schematically a second closure wherein a frame F of square cross-sectional outline accommodates and guides four

vanes

10, 11, 12, 13 respectively having triangular inner portions a-13a and rectangular outer portions 10d-l3. The angles at the apices of the triangular portions 10a-13 are identical and each thereof equals 360l4, i.e., 90. The distance d shown in FIG. 3 equals the distance e and each edge face of each of the triangular portions 10a-13a abuts against and is slidable along one edge face of the adjoining triangular portion. The directions in which the vanes 10-13 can be moved from the outlet-closing positions of FIG. 3 to the fully open positions of FIG. 4 are indicated by arrows. The vanes then define a square passage 14 whose center coincides with the center of the polygon defined by the four guide means of the frame F. The vanes 10-13 can be moved to a desired number of intermediate open positions to provide a passage of desired cross-sectional area; however, in each open position of the vanes, the center of the passage defined by the triangular portions 10a-13a coincides with the point where the apices of such triangular portions meet in the outlet-closing positions of the vanes (FIG. 3).

The present invention can be embodied in a closure with n vanes wherein n is a whole number exceeding two, and the frame for such vanes then preferably defines a regular n-sided polygon. The polygonal passage defined by the vanes has n sides and the apex angles of triangular inner portions of such vanes equal 360ln.

FIGS. 5 and 6 illustrate in greater detail a closure which is analogous to the closure of FIGS. 1-2 and which controls the outlet 37a in the bottom or sidewall 37b of a receptacle (e.g., a ladle) for molten aluminum M. The closure comprises the three vanes 101-103 whose outer portions are received in or form carriages or slides 17, 18, 19. The vanes 101-103 are relatively thick plates consisting of refractory material and are mounted directly below the outlet 37a, as viewed in FIG. 6. The frame 15 for these vanes defines an equilateral triangle and has flanges 15a separably secured to bolts 16 by means of cotter pins 16a. The bolts 16 extend downwardly from the outer panel 370 of the wall 37b.

The frame 15 comprises three guide means or rails 25, 23, 24 having

channels

20, 21, 22 for the

carriages

17, 18, 19, respectively. The rails 23-25 consist of metal and the rail 25 is movable up and down, as viewed in FIG. 5, into abutment with and away from the

rails

23, 24. To this end, the frame 15 comprises an extension 28 providing ways for the end portions of the rail 25 and accommodating a pair of hydraulic or

pneumatic cylinders

26, 27 which bias the rail 25 against the

rails

23, 24. This insures that the edge faces of the vanes 101-103 remain in requisite sealing engagement with each other to completely prevent outflow of molten metal M by way of the outlet 37a (when the vanes assume the closing positions shown in FIGS. 5-6) or to prevent leakage of molten metal between the edge faces when the vanes define a passage of desired cross-sectional area.

The means for simultaneously moving the vanes 101-103 through identical distances comprises three identical hydraulic or

pneumatic cylinders

29, 30, 31 which are respectively mounted on

rails

25, 23, 24 and whose piston rods are coupled to brackets or

projections

32, 33, 34 respectively provided on the

carriages

17, 18, 19. The axes of the cylinders 29-31 are parallel to the respective sides of the triangle defined by the frame F. The means for synchronizing the movements of vanes 101-103 comprises a system of valves (indicated schematically at 129) which supply pressurized fluid to the chambers of cylinders 29-31 at the same rate.

FIG. 6 shows that the vanes 101-103 are sandwiched between two

apertured plates

35, 36 of refractory material. The plate 35 abuts against a washer which is outwardly adjacent to the nozzle 37 defining the outlet 37a. The nozzle 37 also consists of refractory material, the same as the wall 37b. A retaining member 38 is affixed to the frame 15 to hold the plate 36 against movement away from the plate 35. The vanes 101-103 are preferably mounted with some play (in directions toward and away from the outlet 37a) so that the retaining member 38 can exert a necessary pressure which is transmitted to the plate 35.

FIG. 7 illustrates a further closure which comprises three vanes 201-203 having outer portions or carriages 217-219 movable in grooves defined by

rails

225, 223, 224 which form part of a frame 215 having an extension 228 for the movable rail 225. The latter is biased upwardly, as viewed in FIG. 7, by helical springs 39. These helical springs can be replaced by leaf springs, by packages of dished springs.

The means for moving the vanes 201-203 comprises an endless flexible element here shown as a chain 43 which is trained over three

sprocket wheels

40, 41, 42 provided at the corners of the triangle defined by the frame 215. The

numerals

45, 46, 47 denote couplings which respectively secure the

carriages

217, 218, 219 to the chain 43. A linkage 48 is employed to move the vane 203 toward and away from the sprocket wheel 41 whereby the chain 43 insures that the other two vanes share such movement of the vanes 203. Thus, the

chain 43 synchronizes the movements of all vanes by insuring that each vane moves through the same distance and in the same direction. The numeral 44 denotes a turnbuckle or an analogous tensioning device for the chain 43. It is clear that this chain can be replaced by a cable, a belt or another endless flexible element. Furthermore, the chain 43 need not be endless; it may comprise several discrete sections each having its ends attached to two adjoining vanes and a median portion trained over one of the

sprocket wheels

40, 41, 42. The couplings 45-47 are of the type which can be disengaged from the chain 43 so that the latter is then free to move independently of the vanes. Of course, the linkage 48 can be replaced by any other means which is capable of moving one of the vanes 201-203 or the chain 43 in a direction which is parallel to the respective side of the triangle, i.e., in a direction which is normal to the line halving one of the apex angles of triangular portions of the vanes. For example, the chain 43 can be driven by a sprocket wheel or one of the

carriages

225, 223, 224 can be provided with a rack which meshes with a pinion driven by a motor or the like.

The frame of the closure may comprise two or more guide means which are movable relative to the other guide means in a manner as shown for the rail 25 of FIG. 5 or rail 225 of FIG. 7. The force of the biasing means (such as the

cylinders

26, 27 of FIG. 5 or the springs 39 of FIG. 7) determines the pressure with which the edge faces of the vanes abut against each other to prevent leakage. The pressure between the edgefaces of the vanes is distributed with greater uniformity if the frame for the vanes comprises two or more guide means which are biased toward the center of the polygon defined by such guide means.

The vanes 201-203 of FIG. 7 are made of refractory material. However, it is clear that these vanes can consist, at least in part, of metallic material and that the previously described vanes may be entirely made of metal. The material forthe vanes will be selected in dependency on the temperature of molten metal, and other factors which effect the useful life of vanes.

If it is desired to produce a jet of circular cross section, the structure shown in FIG. 1, 3, 5 or 7 may comprise an auxiliary or calibrating nozzle defining a cylindrical or conical passage for molten metal and located downstream of the passage defined by the vanes 1-3, 10-13, 101-103 or 201-203. See the phantom-line nozzle 53in FIG. 6. Such composite closure can be used on all types of receptacles for molten metal-in a steel processing plant or the like. It was found, however, that the polygonal passage defined by three or more vanes of my improved closure insures very satisfactory outflow of molten metal with minimal turbulence.

Another important advantage of the improved closure is that the size of the passage defined by its vanes can be varied infinitely to insure satisfactory outflow of molten metal at a desired rate. The axis of the flow of molten metal remains stationary whatever is the cross section of the passage. Thus, the same type of closure can be used on different types of receptacles to insure outflow at a constant rate or at a variable rate. The means for moving the vanes can be manipulated by hand, by remote control or by a suitable programming system so as to initiate, terminate or regulate the rate of outflow in accordance with a predetermined schedule. Thus, the receptacle employing my improved closure can form part of an auto mated metal processing plant.

Finally, the improved closure is longer-lasting and safer than heretofore known closures for outlets which discharge molten metal. This is due to the fact that the contact with molten metal can be readily confined to selected surfaces of the vanes and that the leakage of molten metal can be reduced or eliminated by resorting to relatively simple pressure applying devices.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of my contribution'to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the claims.

What is clairnedas new and desired to ters Patent is set forth in the appended.

1. For use with a receptacle having an outlet for flowable material, particularly with a receptacle for molten metal, a closure for said outlet including at least three adjoining vanes located in a common plane and each having a triangular portion bounded by two edge faces meeting at an apex and making an angle of 360/n wherein n is the number of said vanes, each edge face of each of said portions abutting against an edge face of the adjoining portion and'said vanes being movable in said plane unidirectionally through equal distances at right angles to the lines dividing the respective first mentioned angles between an outlet closing position in which the apices of said portions are adjacent to each other and a plurality of open positions in each of which said portions define a polygonal passage of different cross-sectional area in registry with said outlet.

2. For use with a receptacle having an outlet for fiowable material, particularly with a receptacle for molten metal, a closure for said outlet including at least three adjoining vanes located in a common plane and each having an isosceles triangular portion-bounded by two edge faces meeting at an apex and making an angle of 360ln wherein n is the number of said vanes, each edge face of each of said portions abutting against an .edge face of the adjoining portion and said vanes being movable in said plane unidirectionally through equal distances at right angles to the lines dividing the respective first mentioned angles between an outlet closing position in which the apices of said portions are adjacent to each other and a plurality of open positions in each of which said portions define a regular polygonal passage of different cross-sectional area in registry with said outlet.

3. A closure as defined in claim 1, wherein at. least said triangular-portion of each of said vanes consists of refractory material.

4. A closure as defined in claim 1, wherein at least said triangular portion of each of said vanes consists of metallic material.

5. A closure as defined in claim 1, further comprising a plurality of .elongated guide means extending along the sides of an n-sided regular polygon, said vanes being located within the area bounded by said guide means and each including a second portion reciprocable along one of said guide means.

6. A closure as defined in claim 1, wherein the point where saidapices abut against each other in the outlet closingpositions of said vanes coincides with the center of said polygon.

7. A closure as defined in claim 6, wherein at least one of said guide means is movable with reference to the other guide be protected by Letmeans and further comprising means for biasing said onev guide means toward the center of said polygon.

8. Aclosure as defined in claim 5, further comprising means for moving the second portions of said vanes along the respective guide means.

9. A closure as defined in claim 8, wherein each of said second portions constitutes a carriage for the respective triangular portion.

10. A closure as defined in claim 8, wherein said means for moving said second portions comprises means for synchronizing the movements of said vanes.

11. A closure as defined in claim 8, wherein said means for moving said second portions comprises a fluid-operated cylinder for each of said vanes and means for regulating the admission and evacuation of fluid from said cylinders to effect movements of said vanes through identical distances.

12. A closure as defined in claim 8, wherein said means for moving said second portions includes a mechanical connection between said vanes insuring movement of all vanes in the same direction and through the same distance in response to movement of any given vane.

13. A closure as defined in claim 12, wherein said mechanical connection comprises an endless flexible element.

14. A closure as defined in claim 13, wherein said flexible element is a chain.

15. A closure as defined in claim 13, wherein said flexible

Claims

1. For use with a receptacle having an outlet for flowable material, particularly with a receptacle for molten metal, a closure for said outlet including at least three adjoining vanes located in a common plane and each having a triangular portion bounded by two edge faces meeting at an apex and making an angle of 360*/n wherein n is the number of said vanes, each edge face of each of said portions abutting against an edge face of the adjoining portion and said vanes being movable in said plane unidirectionally through equal distances at right angles to the lines dividing the respective first mentioned angles between an outlet closing position in which the apices of said portions are adjacent to each other and a plurality of open positions in each of which said portions define a polygonal passage of different cross-sectional area in registry with said outlet.

2. For use with a receptacle having an outlet for flowable material, particularly with a receptacle for molten metal, a closure for said outlet including at least three adjoining vanes located in a common plane and each having an isosceles triangular portion bounded by two edge faces meeting at an apex and making an angle of 360*/n wherein n is the number of said vanes, each edge face of each of said portions abutting against an edge face of the adjoining portion and said vanes being movable in said plane unidirectionally through equal distances at right angles to the lines dividing the respective first mentioned angles between an outlet closing position in which the apices of said portions are adjacent to each other and a plurality of open positions in each of which said portions define a regular polygonal passage of different cross-sectional area in registry with said outlet.

3. A closure as defined in claim 1, wherein at least said triangular portion of each of said vanes consists of refractory material.

5. A closure as defined in claim 1, further comprising a plurality of elongated guide means extending along the sides of an n-sided regular polygon, said vanes being located within the area bounded by said guide means and each including a second portion reciprocable along one of said guide means.

6. A closure as defined in claim 1, wherein the point where said apices abut against each other in the outlet closing positions of said vanes coincides with the center of said polygon.

7. A closure as defined in claim 6, wherein at least one of said guide means is movable with reference to the other guide means and further comprising means for biasing said one guide means toward the center of said polygon.

8. A closure as defined in claim 5, further comprising means for moving the second portions of said vanes along the respective guide means.

14. A closure as defined in claim 13, wherein said flexible element is a chain.

15. A closure as defined in claim 13, wherein said flexible element is a cable.

16. A closure as defined in claim 13, wherein each of said vanes comprises coupling means connecting the respective vane to said flexible element.