GB1592414A

GB1592414A - Sliding gate valve

Info

Publication number: GB1592414A
Application number: GB48173/77A
Authority: GB
Original assignee: USS Engineers and Consultants Inc
Current assignee: USS Engineers and Consultants Inc
Priority date: 1976-11-19
Filing date: 1977-11-18
Publication date: 1981-07-08
Also published as: FR2371260B1; AR215031A1; IN147574B; LU78544A1; ATA824877A; IT1087219B; FR2371260A1; HU178127B; CA1064459A; SE425297B; FI61420B; FI61420C; DD134605A5; SE7713063L; BR7707648A; AT358754B; NO773957L; PL202181A1; NL7712753A; CH624034A5

Abstract

The slide plate held in a frame is designed to be longitudinally displaceable by driving devices (23), the driving devices (23) serving as a supporting device for the frame and the slide plate and thus replacing a separate housing. According to one illustrative embodiment, two such drive units are arranged on the opposite sides of the frame, parallel to the longitudinal direction of the latter, for the purpose of effecting the longitudinal displacement. In a preferred embodiment, further drive units (27), of fundamentally similar design, are arranged on one or both transverse sides of the frame, these drive units serving for the transverse displacement of the frame (21). The drive units can be designed as piston-cylinder units operated by means of a pressurised fluid and having piston rods protruding from the cylinder at both ends or as a driven screw with a travelling motor or as an electric linear motor. <IMAGE>

Description

(54) SLIDING GATE VALVE (71) We, USS ENGINEERS AND CON SULTANTS INC. a corporation organised and existing under the laws of the State of Delaware, United States of America of 600 Grant Street, Pittsburgh, State of Pennsylvania 15230, United States of America do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a sliding gate valve for pouring molten metal, as for example, from the bottom of a receiving vessel such as a ladle or tundish.

A known valve for this purpose and typically includes a slide plate having at least one outlet port and being contained in a movable frame. The slide plate is springbiased upwardly against a head plate located above the slide plate. The head plate contains an opening that communicates with the vessel interior and cooperates with that in the slide plate to pass molten metal from the receiving vessel when the openings are vertically aligned. The head plate is held by a mounting member connected to the bottom of the receiving vessel and the slide gate frame is held by a support device equipped with tensioning means for pressing the frame and its contained slide plate against the head plate.

In known sliding gate valves of the above described type, the frame slides inside a housing forming part of the support device.

Usually the housing is hinged to the mounting plate, and can be pressed against the mounting plate by means of suitable tensioning apparatus, including springs that are compressed between the frame and the slide plate, and thus force the slide plate up against the head plate. A pressure cylinder, operative to move the frame and slide plate relative to the head plate, laterally penetrates the housing to connect with the frame.

The use of an essentially closed housing as a support device has several disadvantages.

A serious drawback is that even minor quantities of escaped liquid metal or other contaminants, for example, tar or sand, can obstruct the free motion of the relatively movable parts, so that the frame and the slide plate contained within it cannot be moved satisfactorily. The resultant operational disruptions can have far-reaching consequences. Furthermore, the fabrication and installation of the housing, the sliding members within it, and the pressure cylinder require considerable constructional effort and expense.

Therefore, it is the aim of the invention to provide a sliding gate valve in which a troublesome and structurally cumbersome housing can be eliminated.

The invention resides broadly in the pro- vision of a sliding gate valve apparatus for a metal pouring vessel, comprising a head plate having an aperture adapted to communicate with the vessel interior; a slide plate movable in its own plane relative to said head plate and containing a pouring aperture co-operable with the aperture in the head plate to control molten metal flow from the vessel interior; a slide plate support member which supports the slide plate against the head plate and at least one drive means to effect movement of the support member and the slide plate relative to the head plate, the support member being fast with and supported by at least one drive member of the drive means, which is supported in turn by another member of the drive means which is in turn supported on the vessel.

More specifically the invention provides a sliding gate valve apparatus for a metal pouring vessel, comprising a head plate having an aperture adapted to communicate with the vessel interior; a slide plate movable along a path in its own plane relative to the head plate and having an aperture cooperable with the head plate aperture to control molten metal flow from the vessel interior, a slide plate support member which supports the slide plate against the head plate and at least one motor unit for effecting movement of the support member and the slide plate along the said path, the (or each) motor unit including a first member supported on the vessel and fixed against movement along the path, and a second member supported by thc first member and displaccable relative thereto upon actuation of the motor unit, the slide plate support member being supported by and fast with the second member so as to be movable therewith along the said path.

In a preferred embodiment of the invention, the supporting housing, and the slide arrangements of the above described prior arrangements are replaced by motor units located on both sides of a frame, which in turn supports the slide plate whereby thcse units also serve as supporting members as well as drives for imparting motion to the frame and slide plate. The elimination of the housing rcsults in a structure that is open on all sides so that it is not liable to be jammed by liquid metal or other contaminants.

Furthermore, the total construction cffort and expense is reduced by a considerable amount.

An especially advantageous further development of the sliding gate valve according to the invention provides an additional pair of motor units for imparting transverse motion to the frame. These additional motors are desirably located on opposite sides of the frame parallel to its trans vcrsc dimension. The stationary components of the units are rigidly connected with respect to the vessel, and the components that are movable in the transverse direction of the frame support the stationary compo nonets of the motor units used for the longitudinal motion of the frame, so that the frame can be moved selectively not only in its longitudinal direction, but also transversely to it. This arrangement is especially advantagcous in that several pouring ports can be incorporated in the slide plate by arranging the ports, for example, in two rows staggered in the longitudinal direction.

With this arrangement, the various ports may have different diameters, so that the metal pouring rate can be varicd without changing the slide plates. Also, an increase in the number of ports increases correspondingly the expected scrvice life of each slide plate. Moreover, the ability to move the frame transversely permits adjustment of the location of the ports in the pouring stream so that the very intensive wear at the edges can be distributed uniformly around the perimeter of each port. A transverse motion of the frame, while maintaining exact guides in the longitudinal as well as in the transverse direction, is not possible with the closed housing constructed in accordance with the known state of technology.

Various forms of tensioning apparatus can be employed in the operation of the gate valve of the present invention. In one embodiment the tensioning apparatus is located between the cylinder components for the longitudinal motion and the frame in a manner well known in the art. In this form the apparatus, on one side, includes a tensionable hinge joint and on the other side a tensionable releasable latch joint. Manually operated tensioning rods, such as those commonly used with gate valves having housings, may be employed in the present gate valve arrangement.

In another form, the tensioning device is located at the junctures between the motor units for the longitudinal motion of the frame and mounting plate, or between the motor units for the transverse motion of the frame. The tensioning device contains eccentric bushings that are rotated by an appropriate lever system to increase or decrease the tension. The lever system is moved in one or another direction by the longitudinal motion of the frame, as required.

Some preferred forms of sliding gate apparatus in accordance with the invention will now be described by way of example, with reference to the accompanying drawings, in which: Figure 1 is a vertical section taken along line 1-1 of Figure 3 illustrating a first embodiment of the sliding gate valve of the present invention; Figure 2 is a schematic plan view of the slide plate used in the sliding gate valve shown in Figure 1; Figure 3 is an isometric view of the sliding gate valve shown in Figure 1; Figure 4 is a schematic representation of the hydraulic system employed in the operation of the sliding gate valve of Figure 3; Figure 5 is a vertical sectional representation taken along line 5-5 of Figure 3; Figure 6 is a sectional view illustrating the sliding gate valve in its unlatched position; Figure 7 is an isometric view illustrating a simplified embodiment of the sliding gate valve in which transverse mobility of the frame is omitted; Figure 8 is an isometric view, similar to Figure 7, illustrating the sliding gate valve with an alternative form of tensioning means; Figures 9 and 10 are illustrations of eccentric bushings utilized in the embodiment of Figure 8; Figure 11 is an isometric view, similar to Figure 7 illustrating the sliding gate valve having an alternative form of motor means; Figure 12 is a partial sectional view of the motor means of Figure 11; and Figure 13 is a plan view of the sliding gate valve equipped with yet another alternative form of motor means.

In Figure 1, the bottom of a receiving vessel such as a ladle is indicated by the reference numeral 11. A mounting plate 12 is attached to the ladle bottom 11. Bclow the mounting plate lies a refractory head plate 13, secured by bolts 14 against horizontal motion. The ladle bottom 11, the mounting plate 12, and the head plate 13 are penetrated by a pouring port 15, which is lined inside with appropriate inserts 16. Adjacent the lower surface of the head plate 13 is located a slide plate 17, which is also made of a refractory material.

The slide plate 17 contains several apertures 18, which are extended downward by tubes 19. The slide plate 17 is biased upwardly against the head plate 13 by means of springs 20. The springs 20 are supported by a slide plate support member constituted by a frame 21, which is movable in the horizontal direction together with slide plate 17 contained within it.

The frame 21 is supported by a support device, which is indicated generally by the reference numeral 22. The support device also serves to move the frame 21 in the horizontal direction. Figure 3 shows the construction and attachment of the support device 22 at the mounting plate 12, which, in Figure 3, is shown detached from the ladle bottom 11.

The support device 22 contains two piston-cylinder units 23 located parallel to the long dimension of the slide plate 17 at opposite sides of it, only one unit being visible in Figure 3. Each piston-cylinder unit 23, for the longitudinal motion of the slide plate 17 comprises a centrally located cylinder 24, which is connected with the frame 21 as shown in Figure 5. Connecting rods 25 extend from opposite ends of a piston 25' (Figure 4) enclosed within the cylinder. The free ends of connecting rods 25 are joined with the free ends of two further connecting rods 26 of the piston-cylinder units 27 located parallel to the lateral dimension of the slide plate 17 and operative to move the frame 21 in the transverse direction as hereinafter described by connector blocks 28 disposed at the four corners of the support device 22. The piston-cylinder unit 27 for the transverse motion of the frame 21 is constructed similarly to the piston-cylinder unit 23, for the longitudinal motion of the frame 21, but its cylinder 29 is rigidly connected with the mounting plate 12 by means of upright supports 30. Thus, the pistoncylinder units 23 and the piston-cylinder units 27, serve to jointly support the frame 21. More specifically the cylinders 29 are fast with plate 12 and support the connecting rods 26 and 25 for movement as a unit in directions parallel with rods 26. The rods 25 support cylinder 24, which in turn support frame 21 and slide plate 17. The pistoncylinder units 23 and 27 can be supplied with a pressurizing agent in a known manner, and therefore can move the frame 21 and slide plate 17 in the longitudinal andlor transverse directions as described in more detail hereinafter.

To move the frame 21 in the direction of the head plate 13 and to force the frame against the head plate, with consequent compression of the springs 20, the embodiment according to Figure 3 provides for a tensioning device located between the cylinder 23 and the frame 21 and indicated in its entirety by the reference numeral 31.

This tensioning device 31 is constructed as a known latch joint which is described in detail in British Patent Specification No.

1 399 011. As shown in Figures 3, 5 and 6, it comprises an articulated lever 32, one member 32a of which is connected with the cylinder 24 and a notch 32b' in the other member 32b engages a horizontal bar 33, whereby the articulated joint 32c is movable beyond the dead-center as is indicated in Figure 5 by the arrow 34. The articulated joint 32c is moved by a locking bar (not shown), which is inserted into a socket opening 35' in boss 35 on the lever 32b. In a similar manner, the hinge, located on the opposite side of the frame 21 between the frame and the cylinder 24, can be tensioned.

This hinge connection, on the opposite side of the frame 21, is of identical construction except that the lever member 32b is permanently pivotably fixed by pins 32d to the frame. In principle, this mechanism is constructed similarly to the hinged joint used in conjunction with a slide gate housing. This construction permits the housing to swing away from the ladle bottom as shown in Figure 6, after unlocking the latch, for example, to insert a new slide plate 17.

The fluid system employed to effect movement of the frame 21 with respect to the mounting plate 12 is as shown in Figure 4. That portion of the system which is operative in conjunction with the motor units 23 to move the frame 21 longitudinally of the mounting plate 12, shown in phantom in the drawing, comprises oppositely acting pairs of parallely-connected lines 50a, 50b, and 51a, 51b that connect between a fluid source (not shown) and the interior of the cylinders 24. As shown in the figure the lines are conveniently formed through the connecting rods 25 and 26 and connector blocks 28. Lines 50a and 50b are caused to communicate at one end with fluid port 52 and extend each to one of the respective cylinders 24, communicating therewith adjacent corresponding sides of the respective pistons 25'. Lines 51a and 51b, on the other hand, are similarly constructed and extend between port 53 and the cylinders 24, communicating therewith on the other corresponding sides of the pistons 25'. It will be appreciated that with the pistons 25', being effectively fixed with respect to the mounting plate 12, in order to move the frame 21 with respect thereto in the upward direction as it appears in the drawing figure, operating fluid is admitted by means of appropriate valving apparatus (not shown) through port 52 and lines 50a and 50b to the interior of the cylinders 24 on the upper sides of the respective pistons 25'. Simultaneously therewith, fluid from the lower sides of the pistons is released from the cylinders through lines 51a and 51b and port 53 to be returned to the source. The effect is to produce a resultant movement of the cylinders 24 and of the attached frame 21 longitudinally with respect to the mounting plate 12 in the upward direction as it is viewed in Figure 4. When it is desired to move the frame 21 in the opposite direction, the described procedure is reversed.

That portion of the fluid system that is operative to move the frame laterally with respect to thc mounting plate 12 comprises oppositely acting lines indicated as 56 and 57 formed interiorly of the thickness of the mounting plate 12. The lines 56 and 57 each connect at one end with the ports 58 and 59 respectively, that are attached to the mounting plate and which communicate with a source of operating fluid that is independent of the previously described source. The lines 56 and 57 have feeders offset therefrom, indicated by the subscripts a and b which communicate with oppositely spaced cylinders 29 of the motor units 27. In construction these offsets extend interiorly of the upright supports 30 which attach the cylinders 29 to the mounting plate 12. Feeders 56a and 56b communicate with the cylinders 29 on corresponding sides of the pistons 26', here shown as being the left side thereof, which feeders 57a and 57b communicate with the cylinders 29 on the opposite sides of the respective pistons. Thus, since the cylinders 29 are effectively fixed with respect to the mounting plate, to move the frame 21 from left to right as viewed in the drawing figure, operating fluid is admitted to line 56 through the port 58 from whence it flows through the line offsets 56a and 56b to the interior of the respective cylinders 29 on the left side of the pistons 26'. At the same time, fluid is released from the cylinders on the opposite sides of the respective pistons through offsets 57a and 57b and port 59 thereby producing a movement of the pistons 26' to the right.

Since the entire support structure 22 and, thereby the frame 21, is operatively fixed to the pistons 26' movement of the pistons 26' to the right produces movement of the frame coincident therewith. When movement of the frame in the opposite lateral direction is desired, this procedure is reversed.

The embodiment of the support device 22' shown in Figure 7 does not provide for transverse motion of the frame 21. In this embodiment of the invention the free ends of the connecting rods 25 of the pistoncylinder units 23 are rigidly connected with the head plate 12 at posts 36. Otherwise the construction shown in Figure 7 corresponds with those shown in Figures 1 and 3, and the corresponding components are identified with the same reference numerals.

The embodiment shown in Figure 8 also does not provide for transverse movement of the frame 21, and to this extent it corresponds with that shown in Figure 7. It differs from the embodiment shown in Figure 7 by the construction of the tensioning device 31.

The tensioning device 31 shown in Figure 8 contains four eccentric bushings 37, which can be rotated in the bearings 38 located on the underside of the mounting plate 12.

Support rods 39 extend through each pair of eccentric bushings 37, and the free ends of the support rods are connected through connectors 40 with the free ends of the connecting rods 25 of the piston-cylinder units 23, for the longitudinal movement of the frame 21. The cylinders 24 of the pistoncylinder units 23, are rigidly connected with the frame 21. By rotating the eccentric bushings 37 in the bearings 38 the support rods 39, the piston-cylinder units 23, and the frame 21 can be raised and tensioned (see Figures 9 and 10). The eccentric bushings are equipped with upward pointing levers 41. The upper ends of two levers 41 on the same side of the frame are joined by a connecting rod 42, which can be moved by the frame 21 in one or the other direction as desired. For this purpose, the connecting rod 42 contains on its underside projections 43, which can be connected with the frame 21 or can be disengaged from it. In this manner the frame 21 can move the connecting rod 42, the levers 41, and the eccentric bushings 3.7 in the direction of increasing or decreasing tension. The tensioning device of this embodiment of the invention is similar to that which is shown and described in greater detail in British Patent Specification No. 1 521 242.

Figures 11 and 13 illustrate alternative forms of motor means for the gate valve herein. In the embodiment of Figure 11 the sliding gate valve and support structure are in all substantial effects the same as those shown in Figure 7 and as described in connection therewith. In this embodiment, however, the hydraulic motor units 23 of Figure 7 are replaced by electrical linear induction motors indicated generally as 60.

The linear induction motors 60 on the opposite sides of the frame 21 each comprise a moving inductor member 61 that is fixedly mounted on a sleeve 62 that attaches one end of the frame 21 and that surrounds an elongated rod 63 forming the secondary or reaction axis of the motor. As shown, the rods 63 are caused to extend between and are fixedly attached to oppositely spaced posts 64, the latter being disposed at the four corners of the mounting plate 12. In this embodiment of the invention, movement of the frame 12 is effected by imposing an electric current through the coils of the inductor members 61 to produce an axial movement thereof along the rods 63 thereby moving the frame 21 longitudinally of the mounting plate 12.

In the embodiment of Figure 13, the frame 21 is driven by a reversible electric motor 70 through appropriate worm gearing and drive screws. As shown in the drawing figure the frame 21 is attached at its opposite ends to movable nut members 71. The nut members 71 are operated by drive screws 72 that extend along opposite sides of the mounting plate 12 between corner posts 73 and 74. Posts 73 contain appropriate bearings to permit rotation of the respective drive screws while posts 74 contain, in addition to the bearings, worm gear means to effect rotation of the drive screws, all as is well known in the art. The worm gears are in turn driven by a reversible electric motor 75 suspended from the mounting plate 12. The motor 75 connects with the respective worm gear apparatus through oppositely extending drive shafts 76 each of which contains clutch apparatus 77.

Thus the weight of the frame and slide plate is taken by the nut members 71 and so to the drive screws 72 and mounting plate 12.

While the motor 75 has been described as being a reversible electric motor, this motor may, in some applications, preferably be a pressure-actuated motor, such as, for example, a compressed alr motor.

It will be understood that various changes in the details, materials and arrangements of parts which have been herein described and illustrated, in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended

Claims

claims. WHAT WE CLAIM IS:

1. A sliding gate valve apparatus for a metal pouring vessel, comprising a head plate having an aperture adapted to communicate with the vessel interior; a slide plate movable in its own plane relative to said head plate and containing a pouring aperture co-operable with the aperture in the head plate to control molten metal flow from the vessel interior; a slide plate support member which supports the slide plate against the head plate and at least one drive means to effect movement of the support member and the slide plate relative to the head plate, the support member being fast with and supported by at least one drive member of the drive means, which is supported in turn by another member of the drive means which is in turn supported on the vessel.

2. A sliding gate valve apparatus for a metal pouring vessel, comprising a head plate having an aperture adapted to communicate with the vessel interior; a slide plate movable along a path in its own plane relative to the head plate and having an aperture co-operable with the head plate aperture to control molten metal flow from the vessel interior, a slide plate support member which supports the slide plate against the head plate and at least one motor unit for effecting movement of the support member and the slide plate along the said path, the (or each) motor unit including a first member supported on the vessel and fixed against movement along the path, and a second member supported by the first member and displaceable relative thereto upon actuation of the motor unit, the slide plate support member being supported by and fast with the second member so as to be movable therewith along the said path.

3. An apparatus as claimed in claim 2, in which said slide plate support member is constituted by a frame movable with said slide plate and having spring means for biasing said slide plate against said head plate, said frame being attached to and supported by the said second member of the (or each) motor unit.

4. An apparatus as claimed in claim 2 or claim 3 having two parallel motor units arranged for simultaneous actuation and disposed on opposite sides of said slide plate.

5. An apparatus as claimed in claim 4, in which said slide plate support member is constituted bv a frame movable with said slide plate, one side of said frame being hingedly connected to one of said motor units and the other side of said frame being releasably latched to the other of said motor units.

6. An apparatus as claimed in any one of claims 2 to 5 including a mounting plate for attachment to said vessel and secured to said head plate, and support posts depending from opposite ends of said mounting plate, said first member comprising a connecting rod extending from opposite ends of said second member and connected to said posts, said second member being movable along said connecting rod.

7. An apparatus as claimed in any one of claims 2 to 5, including an additional motor unit disposed transversely of the first motor unit or units, said additional motor unit including a first member and a second member movable relative thereto, means attaching said first member with respect to said head plate and means attaching said second member with respect to the first member of the first said motor unit or units, whereby said slide plate is movable along a longitudinal axis and a transverse axis per pendicular thereto.

8. An apparatus as claimed in claim 7, having two parallel motor units operable to effect movement along the transverse axis and arranged for simultaneous actuation and disposed on opposite sides of said slide plate.

9. An apparatus as claimed in claim 7 or claim 8, including a mounting plate for attachment to said vessel and secured to said head plate, the second member of the or each additional motor unit comprising a connecting rod extending from opposite ends of the first member, and the first member of the or each first motor unit comprising a connecting rod extending from opposite ends of the second member, means attaching the first member of the or each additional motor unit to said mounting plate and means joining the adjacent free ends of said connecting rods.

10. An apparatus as claimed in any one of claims 2 to 9, in which the or each motor unit comprises a fluid pressure activated piston cylinder unit.

11. An apparatus as claimed in claim 10 when dependent on claim 6 or claim 9 in which said piston-cylinder unit of the or each first mentioned motor unit has a piston rod which constitutes said connecting rod and which has a passage for the introduction of pressurized fluid into the cylinder.

12. An apparatus as claimed in any one of claims 2 to 9 in which the or each motor unit comprises a linear induction motor.

13. An apparatus as claimed in any one of claims 2 to 9 in which the or each motor unit comprises a screw threaded rod operably connected to a reversible rotary motor and a screw threaded nut in screw-threaded engagement with said rod.

14. An apparatus as claimed in claim 13, in which said rotary motor is a fluid pressure activated motor.

15. An apparatus as claimed in claim 13 in which said rotary motor is an electric motor.

16. An apparatus as claimed in any one of claims 2 to 1 5 in which the slide plate has a plurality of pouring apertures diposed in staggered relation.

1 7. An apparatus as claimed in claim 2, in which the head plate is secured to a mounting plate to which is secured the first member of the said one motor unit, the second member of the motor unit being fast with a frame movable along a first axis by actuation of the one motor unit, the said frame supporting the slide plate for movement along a second axis perpendicular to the first axis, and wherein a second motor unit is provided for effecting movement of the frame along said second axis, the second motor unit having a first member fast with the second member of the first motor unit and a second member fast with the frame, the first and second motor units being operable independently of each other to displace the slide plate along the two said axes to produce a desired resultant path of movement of the slide plate relative to the head plate.

18. A sliding gate valve apparatus for a metal pouring vessel, constructed and adapted to operate substantially as hereinbefore described with reference to and as illustrated in Figure 1 to 6 of the accompanying drawings.

19. A sliding gate valve apparatus for a metal pouring vessel, constructed and adapted to operate substantially as hereinbefore described with reference to and as illustrated in Figure 7 of the accompanying drawings.

20. A sliding gate valve apparatus for a metal pouring vessel, constructed and adapted to operate substantially as hereinbefore described with reference to and as illustrated in Figures 8 to 10 of the accompanying drawings.

21. A sliding gate valve apparatus for a metal pouring vessel, constructed and adapted to operate substantially as hereinbefore described with reference to and as illustrated in Figures 11 and 12 of the accompanying drawings.

22. A sliding gate valve apparatus for a metal pouring vessel, constructed and adapted to operate substantially as hereinbefore described with reference to and as illustrated in Figure 13 of the accompanying drawings.