CA1103921A

CA1103921A - Throttling molten metal teeming valve

Info

Publication number: CA1103921A
Application number: CA271,970A
Authority: CA
Inventors: Earl P. Shapland; Patrick D. King
Original assignee: Flo Con Systems Inc
Current assignee: Flo Con Systems Inc
Priority date: 1976-10-15
Filing date: 1977-02-17
Publication date: 1981-06-30
Also published as: FR2367569A1; DE2746265A1; MX146103A; CS216909B2; LU78322A1; FI773027A; CH627103A5; YU242677A; IT1091183B; AU512164B2; NL7711330A; PL113655B1; GB1584628A; FR2367569B1; AU2925877A; AT359224B; ZA775824B; IN147808B; SE433713B; HU176626B

Abstract

ABSTRACT OF THE DISCLOSURE
The specification of the present application discloses a sliding gate valve having independent means for throttling a stream of metal during the teeming opera-tion. The structure comprises a sliding gate valve frame at the lower portion of a teeming vessel and a top plate positioned beneath the vessel having an orifice in open communication with the teeming opening in the bottom of the vessel. The structure also includes a sliding gate having a teeming opening positioned beneath the top plate and means for holding the sliding gate in fluid tight relationship with the top plate. Means are provided for moving the sliding gate into and out of the teeming position, and means in addition to and independent of the means for moving the sliding gate into and out of the teeming position for misaligning of the sliding gate from its full flow position.
By providing these two independent positioning means it is much simpler to achieve a constant flow rate during ceeming.

Description

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BA~KGROUND OF INVENTION
Field of Invention The field of invention is the one of pouring, or teeming molten fluids such as steel, iron, aluminum, brass, and glass, which are only fluid at temperatures elevated above normal environmental temperatures. More particularly, the invention relates to an apparatus for accomplishing throttling of the teeming stream without interfering with the on-off function of the valves controlling the teeming from the bottom of a bottom pouring vessel. The method is directed to the independent shifting of the sliding refractory ~ -block or gate, and apparatus specific for that purpose is contemplated.

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Description of the Prior Art -The field of invention is generally described in , United States Patents Nos. 311,902; 1,507,852; 3,436,023;
and 3,454,201. United States Patent No. 3,352,465 and its re-issue No. Re 27,237 entitled "Refractory Closure Member for Bottom Pour Vessels" discloses s~quential refractory valving which is spring loaded against a fixed top plate generally indicative of the environment in which the present nvention finds its utility. More recently issued United States Patent No. 3,866,806 discloses a method of throttling using a check cylinder to stop the gate short of a full stroke.
Ea~h of the foregoing identified patents and its associated structure suffer from the disadvantage of being unable to .
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adjust the degree of throttling action independent of the emergency shutoff function of the valves. Such action is particularly desirable when aluminum killed steel, in particular, is run through a continuous caster. The aluminum oxide formed as a result of the killing process has an affinity toward the side wall of the teeming opening as well as the pour tube. It ultimately can clog both. It is, therefore, necessary with a continuous caster to be able to change the slide valve as well as the gate and tube. This is accomplished, particularly in the construction as disclosed in Patent No.
3,352,465 (Re 27,237) by passing an imperforate plate into position, and replacing the other element.

Summary The present invention is based upon the capability, while teeming, to control the rate of flow even though clogging or erosion is taking place in theteeming orifice.
20 The valve shifts the teeming orifice of one refractory member into and out of alignment with the teeming orifices of other refractory members. Desirably the teeming orifice is elongate along the axis of the axis of throttling.
The method contemplates throttling the stream to compensate for the affects of clogging due to material of erosion of the orifice material, and the affect of varying changes in desired teeming rates.
lt is accordingly a principal object of the present invention to provide both a mechanism or apparatus and a method which will permit throttling of the teeming stream in the environment of existing reciprocating or sequential

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valves.
It is a further object, an important object, of the present invention to provide an apparatus and method which will permit throttling of a teeming stream independently of the emergency shut-off or plate changing functions of the device.
Still another object of the present invention is achieved by an apparatus and method capable of shutting or closing a throttled stream and then reopening the same to the previous degree of throttling without hunting or seeking the previous : degree of throttle, since the lateral shifting can be controlled independent of the shut-off means.
Still another object of the present invention is to I provide the subject apparatus which inherently causes little or no significant increase in the expense of operation from pre-existing reciprocating valves which cannot provide for throttling independent of the emergency shut-off function.
;, Yet another object of the present invention is to ~ provide an apparatus and method for throttling which will j 20 permit significantly longer pouring cycles without shutdown , for cleaning, lancing, and other remedial activity than ,; heretofore available.
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DESCRIPTION OF ILLUSTRATIV~ DRAWINGS
Further objects and advantages of the present invention will become apparent as the following description of two illustrative embodiments and methods proceeds, taken in conjunction with the accompanying drawings in which:
FIG. 1 is an oblique section of a bottom pour vessel, here illustrated as a tundish, on which a sequential valve is mounted. The section is taken along a center line which is the main direction of travel of the sliding plate.
FIG. 2 is a sectional view taken at right angles to the section of FIG. 1, shown as Section Line 2-2 of FIG. 1.
FIG. 2 shows the sliding plate offset to one side to cause throttling of the stream. In the embodiment illustrated in FIG. 2, the submerged pouring tube is offset with the sliding plate.
FIG. 3 is taken from a similar elevation and section and scale as FIG. 2, illustrating a submerged pour tube which is not offset with the sliding plate, but remains in line with the upper stationary plate.
FIG. 4 is a further oblique section of a bottom pour vessel, here illustrated as a ladle, on which a reciprocating .. . .
ladle valve is mounted. The section, as is section 1, is ta~en along a center line which is the direction of travel of the reciprocating slide plate.
FIG. 5 is a cross-section of the valve shown in FIG. 4, taken at right angles to the section of FIG. 4, as indicated ;~ by Section Line 5-5 of FIG. 4.
FIG. 6 is an enlarged transverse sectional view of a , typical alternative commercial embodiment for a tundish such as is shown in FIG. 1.

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,, FIG. 7 is taken from vantage point 7-7 of FIG. 6, illustrating an elongate configuration of the sliding plate.
FIG. 8 is a transverse view of the pour opening taken along section line 8-8 of FIG. 7.
FIG. 9 is a downward looking view of the pouring mechanism taken essentially from the section or vantage point disclosed by section lines 9-9 of FIG. 6.

De-scription of Illustrative Embodiments FIG. 1 illustrates a tundish 1 with its refractory lining ~. Mounted on the bottom of the tundish is a stationary mounting plate 3 which holds the refractory stationary top plate 4 in a fixed position relative to the stationary mounting plate. Support rods ~ are atta~hed to the stationary mounting plate and they support the slide gate support frame 6 which has slide gate support rails 7. The gate change cylinder 8 is fastened to the slide gate support frame 6 and the submerged pour tube support frame 9 with its support rails 10 suspended below the slide gate support frame 6.

51ide gate plates S are inserted from position 11 to position 12, then the cylinder 8 pushes them to operating position 13 at the same time pushing a used plate from position 13 to position 14. Slide plates may be imperforate or blanks for shut-off as shown at 12 or perforate with teeming openings as shown at 13 and L4. As shown in FIG. 1, the unit is ;~ equipped with a submerged pour tube although it may be operated without a submerged pour tube. The submerged pour tube holder 15 and submerged pour tube 16 are supported by the submerged pour tube support frame 9 and its support rails.

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FIG. 2, a cross section taken at right angles to the section shown in FIG. 1, illustrates how throttling is accomplished. The slide gate support frame 6 is offset to the right thus causing misalignment between the orifice in stationary top plate 4 and the orifice in the slide gate plate 13, and thus throttling the stream. The slide gate support frame 6 slides on the support rods 5 and in this instance is moved by hydraulic throttling cylinder 17 although it could be moved by levers or screws either manually or electrically operated. In the embodiment of FIG. 2 the submerged pour tube support frame 9 is rigidly connected to the slide gate support frame 6 so the submerged pour tube holder 15 and submerged pour tube 16 are offset with the slide gate plate 13 and remain aligned with it.
FIG. 3 illustrates the same section as FIG. 2 but of a slightly different embodiment. In this embodiment, the submerged pour tube support frame 9 is fastened rigidly to the stationary mounting plate 3 so that when the hydraulic cylinder 17 offsets the slide gate support frame 6 and slide ~ -gate plate 13 as shown, the submerged pour tube support frame 9, submerged pour tube holder 15, and submerged pour ; ~ tube 16 remain in alignment with the refractory stationary i top plate 4 which is retained by the stationary mounting plate 3.

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First Alternative Embodiment FIG. 4 illustrates a ladle 18 with its refractory lining 19. Mounted on the bottom of the ladle is a stationary mounting plate 20 which holds the refractory stationary top ;~ plate 21 in a fixed position relative to the stationary mounting plate and also supports the slide gate support frame 27 by means of gibs which are not visible in this view but are illustrated in FIG. 5.
At the position shown in FIG. 5, the operating linkage 23 has pulled the slide gate carrier 24 and slide gate 25 to the right until it is against the stop built into the slide gate support frame 27. This would be its normal full open position but, as shown, throttliny cylinder 26 has shifted the entire slide gate support frame 27 to the right a distance equal to about one-third of the orifice throttling the stream through the orifice. Note that throttling could as well be accomplished by shifting the slide gate support frame to the left. The choice as to which of these modes of operation depends on wheth r it is desirable to throttle on the front or back side of the slide gate 25 and upon whether or not the ability to move to a full open position without operation of the throttling cylinder 26. Note also that the valve may be quickly shut off by extending the operating cylinder without the need to operate the throttling cylinder.
FIG. 5, a cross section taken at a right angle to the cross section of FIG. 4, illustrates one method of supporting the sliding gate support frame 27 so that it may be shifted relative to the stationary mounting plate 20 thus shifting the orifice in the sliding gate 25 out of alignment with the orifice in the refractory stationary top plate 21 and the '~ ladle lining 19. Flanged gibs 28 are screwed to the stationary ` 1 ~.
mounting plate 20 by means of cap screws 29. The flange portion of the gibs 28 engage the flange portions of the ; sliding gate support frame 27 supporting it in a fixed vertical position but allowing motion in one direction while g~iding it in other directions. Stops may be affixed to the gibs ~o limit the travel of the sliding gate support frame : ' ' :, _g_ ,~
' Second Alternative Embodiment Yet another alternative embodiment is shown in transverse section in FIG. 6, the section being taken transverse to the direction of longitudinal movement of the slide gate block 'S'. As this particular embodiment is described, the parts which are common with the first and second embodiment will be designated with a prime such as tundish 1', which is the vessel employed. The refractory 2' lines the interior of the tundish 1', and therebeneath a mounting plate 3' is positioned. The top plate 4' as noted is encased in metal, and is immediately beneath the teeming opening of the tundish 1'. The frame 6' surrounds the top plate 4', and interiorly thereof are mounted slide gate support rails 7' for movement of the slide gate S' by means of the drive cylinder 8' (shown on FIG. 9).
A tube support ~rame 9' is positioned beneath the tube support rails 10'. As will be noted in FIG. 9, the sliding gate S' is shown there positioned at position 11 for transverse movement into the assembly for subsequent driving by means of the cylinder 8'. The tube holder 15' is positioned beneath the sliding gate S', and supported by means of the ~' tube support frame 9' as described. The tube holder 15' is e encased in metal as are the top plate 4' and the slide ~t~F

Sl. The tube 16' extends downwardly from the tube holder 15' and the entire assembly is actuated laterally by means of the throttling cylinder 17'. The throttling cylinder 17', particularly as shown in the right hand portion of FIG.

6 and the two o'clock position in FIG. 9, drives a cross link 30 which coacts with the bell crank 31, to drive the crank shaft 32 by means of its coupling with the crank arm 33. The yoke 34, as shown particularly in FIG. 9, is provided ; with opposed push rods 5 which act against the slide gate ':

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support rail 7 for throttling when the slide plate S' is shifted laterally into the configuration as shown in FIG. 6.
Spring loaded push rods 37 activated by springs 36 bear against rocker arms 38 coacting with the pivot 39 to the end that the action of the spring 36 causes the rocker arms 38 to bear upwardly against the lower metal encased portion of the tube holder 15' to urge the same into compressive relationship with the sliding gate S and the stationary top plate 4'.
As noted in FIGS. 7 and 8, the orifice in the sliding lQ gate S is elongate in the axis of throttling. This con-figuration is highly desirable to maximize the opening at the termination of the pouring effort, prior to total clogging;
and conversely to permit a relatively small total opening when the pour begins prior to any clogging. To be observed is the configuration of the elongate orifice specifically as shown in FIG. 7, where the same is provided with an obround or racetrack-like configuration. Alternatively, an elliptical configuration may also be employed. In the total throttled condition, the plan view of the total orifice is essentially circular, but as the orifice is opened by means of the actuation of the throttling cylinder 17', the overall opening is more closely that shown in FIG. 7, obscured onl~ by the extent to which clogging has occurred.
In this manner, maximum throttling can be achieved while maintaining a compact stream. Further, it is contemplated that perforate plates having different short axis orifices will be used while all will have the same long axis. As the length of the long axis will be a function of the total stroke of the throttling mechanism, the maximum per cent of throttle available will be the same for each different . .

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-` P~ 21 size orifice used. In the illustration here, ~IGS. 5,6, 7,8 & 9, the stroke of the throttling mechanism is one half the long axis length of the orifice. Therefore, the maximum degree of throttle is the same for several orifice sizes.
The elongate or elliptical opening allows the use of plates of various opening areas in a mechanism of fixed throttle travel while avoiding over-throttling which dsrupts the stream flow and results in high erosion in the area below the point of throttle.

The Method The method contemplated by the present invention com-prises the steps essentially as set forth hereinafter:
1. Providing a molten material container or holder such as a ladle or a tundish with a means at its lower portion to have a lower sliding surface, having a central teeming opening.

2. Positioning a sliding gate beneath the lower surface.

3. Moving the sliding gate beneath the top plate to a normally open position.

4. Throttling the open position by moving the sliding ~ gate independent of its moving to a normally open position.
;~ 5. Qptionally but desirably providing an elongate oriflce in the sliding plate which is positioned with its long axis ideally coincident with the path of throttling movement of the sliding gate.
6. Desirably positioning the sliding gate initially in the most closed configuration due to maximum lateral dis-placement, and thereafter progressively opening the orifice as clogging takes place until such time as it is necessary to remove the sliding gate for cleaning and lancing any orifices, or reverse in the event of pouring of eroding materials.
7. Positioning a shut-off plate into the assembly at such time as clogging has proceeded to an undesirable point whereupon the tube or lower pour confining member may be replaced, the top plate lanced, and another sliding gate inserted for further pouring in the sequence as just described.
Essential to the method, irrespective of the desirable steps set forth in Nos. 5 through 7 above, is the lateral - shifting of the sliding plate in order to accomplish the desired amount of throttling or unthrottling, as may be dictated by the pour itself.
Although particular embodiments of the invention have been shown and described in full here, there is no intention to thereby limit the invention to the details of such embodiments. On the contrary, the intention is to cover all modifications, alternatives, embodiments, usages and equivalents of a throttling teeming gate valve and method as fall within ~ 20 the spirit and scope of the invention, specification and the ;~ appended claims.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A sliding gate valve having independent means for throttling a stream of metal during teeming comprising, a sliding gate valve frame at the lower portion of the teeming vessel, a top plate positioned beneath the vessel having an orifice in open communication with a teeming opening in the bottom of the vessel, a slide gate having a teeming opening positioned beneath said top plate, means for holding the sliding gate in fluid tight relationship with the top plate, means for moving said sliding gate into and out of a teeming position and means in addition to and independent of the means for moving said sliding gate into and out of teeming position for misaligning the sliding gate from its full flow position, whereby the teeming stream may be throttled.

2. In the valve of Claim 1, an elongate orifice in the slide gate, said orifice being elongated along an axis coinci-dent with axis of misalignment and throttling.

3. In the valve of Claim 1, yieldable means for holding the slide gate against the top plate.

4. In the valve of Claim 1, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

5. In the valve of Claim 2, yieldable means for holding the slide gate against the top plate.

6. In the valve of Claim 2 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

7. In the valve of Claim 3 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

8. A sliding gate valve for throttling of metal while being teemed comprising a sliding gate valve frame at the lower portion of the teeming vessel, a top plate positioned beneath the vessel having an orifice in open communication with a teeming opening in the bottom of the vessel; a slide gate having a teeming opening positioned beneath said top plate, a member having a teeming orifice positioned beneath the slide gate in substantially fixed orientation with regard to the teeming openings of the top plate and vessel, means for holding the said member against the sliding gate in fluid tight relationship, means for moving said slide gate into and out of a teeming position, and means in addition to and inde-pendent of the means for moving said sliding gate into and out of the teeming position for misaligning the sliding gate from its full flow position, whereby the teeming stream may be throttled.

9. In the valve of Claim 8, an elongate orifice in the slide gate, said orifice being elongated along an axis coinci-dent with axis of misalignment and throttling.

10. In the valve of Claim 8, yieldable means for holding the slide gate against the top plate.

11. In the valve of Claim 8, yieldable means for holding said member beneath the slide gate.

12. In the valve of Claim 8 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

13. In the valve of Claim 9, yieldable means for holding the slide gate against the top plate.

14. In the valve of Claim 9, yieldable means for holding said member beneath the slide gate.

15. In the valve of Claim 13 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

16. In the valve of Claim 9 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

17. In the valve of Claim 10 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

18. In the valve of Claim 11 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

19. A sliding gate valve for throttling of metal while being teemed comprising, a sliding gate valve frame at the lower portion of the teeming vessel, a top plate positioned beneath the vessel having an orifice in open communication with a teeming opening in the bottom of the vessel, a slide gate having a teeming opening positioned beneath said top plate, a member having a teeming orifice positioned beneath the slide gate in substantially fixed orientation with regard to the teeming opening of the slide gate, means for holding the said member against the sliding gate in fluid tight relationship, means for moving said slide gate into and out teeming position and means independent of and in addition to the means for moving for misaligning the sliding gate and said member from their full flow position whereby the teeming stream may be throttled.

20. In the valve of Claim 19, an elongate orifice in the slide gate, said orifice being elongated along an axis coin-cident with axis of misalignment and throttling.

21. In the valve of Claim 19, yieldable means for holding the slide gate against the top plate.

22. In the valve of Claim 19 yieldable means for holding said member beneath the slide gate.

23. In the valve of Claim 20 above a throttling cylinder coupled by means of a bell crank to crank shaft, a yoke positioned along the crank shaft and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

24. In the valve of Claim 20, yieldable means for holding the slide gate against the top plate.

25. In the valve of Claim 20 yieldable means for holding said member beneath the slide gate.

26. In the valve of Claim 21 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

27. In the valve of Claim 25 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

28. A sliding gate valve for throttling a stream of metal during teeming from a vessel comprising, a top plate positioned beneath the vessel having an orifice in open communication with a teeming opening in the bottom of the vessel, a sliding gate valve frame at the lower portion of the teeming vessel arranged to support and guide a slide gate, a slide gate with a teeming opening positioned beneath the top plate arranged so that its teeming opening may be shifted into and out of alignment with the teeming openings in the top plate and bottom of the vessel, a drive means for moving the slide gate so that its orifice moves into and out of alignment with the teeming openings of the top plate and vessel, means in addition to and independent of the means for moving said sliding gate into and out of teeming posi-tion for misaligning the sliding gate from its full flow position.
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29. In the valve of Claim 28, an elongate orifice in the slide gate, said orifice being elongated along an axis coinci-dent with axis of misalignment and throttling.

30. In the valve of Claim 28, yieldable means for holding said member beneath the slide gate.

31. In the valve of Claim 29, yieldable means for holding said member beneath the slide gate.

32. In the valve of Claim 28 above,a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke posi-tioned along the crank shaft and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

33. In the valve of Claim 29 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft, and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

34. In the valve of Claim 30 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

35. In the valve of Claim 31 above, a throttling cylinder coupled by means of a bell crank to a crank shaft, a yoke positioned along the crank shaft and opposed push rods coupled to said yoke for engaging a slide plate and moving the same laterally.

36. A sliding gate valve as claimed in Claim 8 wherein said top plate is a refractory slab and wherein said sliding gate is a refractory slab having a teeming orifice at its central portion, said orifice being elongated along an axis coincident with the path of throttling and wherein said refractory slabs are held in fluid tight relationship.

37. In the sliding gate of Claim 36, said teeming orifice being abround.

38. In the sliding gate of Claim 36, said teeming orifice being elliptical.

39. In the sliding gate of Claim 36, said refractory slab being metal encased about its periphery.

40. In the sliding gate of Claim 36, support rail means intermediate the top and bottom of said slab and parallel to the normal axis of movement.

41. In the sliding gate of Claim 37, said teeming orifice being elliptical.

42. In the sliding gate of Claim 37, said refractory slab being metal encased about its periphery.

43. In the sliding gate of Claim 38, said refractory slab being metal encased about its periphery.

44. In the sliding gate of Claim 41, support rail means intermediate the top and bottom of said slab and parallel to the normal axis of movement.

45. In the sliding gate of Claim 42, support rail means intermediate the top and bottom of said slab and parallel to the normal axis of movement.

46. A method of teeming a molten material comprising the steps of providing a molten material container such as a ladle or a tundish with a means at its lower portion to have a lower sliding surface, said surface having a central teeming opening, positioning a sliding gate beneath the lower surface, moving the sliding gate beneath the lower sliding surface means to a normally open position, throttling the open position by moving the sliding gate independent of its moving to a normally open position.

47. In the method of Claim 46 providing an elongate orifice in the sliding gate which is positioned with its long axis coincident with the axis of throttling movement.

48. In the method of Claim 46, positioning the sliding gate initially in the most closed configuration due to maximum lateral displacement, and thereafter progressively opening the orifice as clogging takes place until such time as it is necessary to remove the sliding gate for cleaning and lancing any orifices.

49. In the method of Claim 46 positioning the sliding gate initially in the most open configuration due to alignment with the central vertical axis of the stationary lower sliding surface teeming opening and thereafter progressively closing the orifice as erosion takes place until such time as it is necessary to replace the sliding gate.

50. In the method of Claim 96, positioning the sliding gate initially at a position providing an opening intermediate to its fully open and fully throttled positions and thereafter shifting it to a more open or more closed position in order to adjust the rate of teeming from the vessel.

51. In the method of Claim 46 providing a tube or lower stream confining member beneath the slide gate, positioning an imperforate plate into the assembly at such time as clogging has proceeded to an undesirable point whereupon the tube or lower stream confining member may be replaced, the teeming opening of said lower sliding surface lanced, and another sliding gate inserted for further pouring in the sequence as just described.

52. In the method of Claim 47, positioning the sliding gate initially in the most closed configuration due to max-imum lateral displacement, and thereafter progressively open-ing the orifice as clogging takes place until such time as it is necessary to remove the sliding gate for cleaning and lancing any orifices.

53. In the method of Claim 47, positioning the sliding gate initially in the most open configuration due to alignment with the central vertical axis of the stationary lower sliding surface teeming opening and thereafter, progressively closing the orifice as erosion takes place until such time as it is necessary to replace the sliding gate.

54. In the method of Claim 47, positioning the sliding gate initially at a position providing an opening intermediate to its fully open and fully throttled positions and thereafter shifting it to a more open or more closed position in order to adjust the rate of teeming from the vessel.

55. In the method of Claim 47, providing a tube or lower stream confining member beneath the slide gate, positioning an imperforate plate into the assembly at such time as clogging has proceeded to an undesirable point whereupon the tube or lower pour confinging member may be replaced, the teaming open-ing of said lower sliding surface lanced, and another sliding gate inserted for further pouring in the sequence as just described.

56. In the method of Claim 48, providing a tube or lower stream confining member beneath the slide gate, positioning an imperforate plate into the assembly at such time as clogging has proceeded to an undesirable point whereupon the tube or lower pour confining member may be replaced, the teaming opening of said lower sliding surface lanced, and another sliding gate inserted for further pouring in the sequence as just described.

57. In the method of Claim 52, providing a tube or lower stream confining member beneath the slide gate, positioning an imperforate plate into the assembly at such time as clogging has proceeded to an undesirable point whereupon the tube or lower pour confining member may be replaced, the teaming opening of said lower sliding surface lanced, and another sliding gate inserted for further pouring in the sequence as just described.

58. A method of teeming a molten material comprising the steps of; providing a molten metal container such as a ladle or tundish with a means at its lower portion to have a lower sliding surface, having a teeming opening in communication with the teeming opening of the vessel, positioning a reciprocating sliding gate having a central teeming opening beneath said lower sliding surface, providing a means for moving the sliding gate so that its teeming opening moves into and out of align-ment with the teeming openings of the lower sliding surface and the vessel.