US3523684A - Vacuum vessel with inlet closure and provision for sealing engagement with teeming ladle - Google Patents

Description

Aug. 11, 1970 T cusc o ET AL 3,523,684 VACUUM VESSEL WITH INLET' CLOSURE AND PROVISION FOR SEALING ENGAGEMENT WITH TEEMING LADLE Filed May 51, 1968 2 Sheets-Sheet 1 IHH I' I'll %' Arlrney Aug. 11, 1970 T. A. CUSCINO ET AL 3,523,684

VACUUM VESSEL WITH INLET CLOSURE AND PROVISION FORv SEALING ENGAGEMENT WITH 'IEEMING LADLE Filed May 51, I968 2 Sheets-Sheet 2 IN VEN TORS. THOMAS A. CUSC/IVO 8 Alfa ney HERMAN 0. SMITH y United States Patent VACUUM VESSEL WITH INLET CLOSURE AND PROVISION FOR SEALING ENGAGEMENT WITH TEEMING LADLE Thomas A. Cuscino, Baldwin Borough, and Herman O. Smith, Pittsburgh, Pa., assignors to United States Steel Corporation, a corporation of Delaware Filed May 31, 1968, Ser. No. 733,679 Int. Cl. C21c 7/06 US. Cl. 266-34 6 Claims ABSTRACT OF THE DISCLOSURE A bottom-pour teeming ladle has a bearing plate surrounding the nozzle thereof and sealed thereto. A vacuum degassing vessel adapted to receive molten metal from the ladle has a cover with an inlet therein. A pressure plate on the cover has an opening therethrough alined with said inlet. Centering rollers on the cover guide up and down movement of the pressure plate. Fluid-pressure cylinders and pistons on the cover raise and lower the pressure plate. A panel slidable on the pressure plate is effective in one position to close said opening, An expansible ring around the edge of the pressure plate is eifective to make sealing engagement with the bearing plate of the ladle when the pressure plate is raised. A bellows extending between the bearing plate and pressure plate encloses said opening and a pouring tube extending downwardly therefrom. A neck on the cover extends upwardly around the tube within the bellows.

This invention relates to a vacuum vessel for degassing liquid metal received from a teeming ladle and, in particular, to provisions for closing and sealing the vessel inlet, so it can be evacuated before the ladle is brought to it and so the vessel can be repressurized after the ladle has been removed.

It is known to degas molten metal by teeming it from a ladle into a vacuum vessel or bottle. Present practice requires that the teeming ladle be attached to the vessel before pumping the latter down to a high vacuum; also that the ladle remain attached after teeming until the vessel has been repressurized to control the flow of metal from the vessel into a mold th rebelow. This practice permits some loss of temperature from the metal before teeming can be started and ties up the ladle for an excessive length of time. We have invented a vessel and ladle structure which permits the vessel to be pumped down before the ladle is attached and also repressurization of the vessel after teeming is completed, without keeping the ladle in position thereon.

BRIEF SUMMARY OF THE INVENTION In a preferred embodiment, we mount a bearing plate horizontally on the bottom of the ladle surrounding the nozzle thereof and provide a seal between it and the ladle bottom. We mount a pressure plate on the vacuumvessel cover, having an opening alined with the vessel inlet, and provide means for moving it upwardly to engage the ladle bearing plate. Centering rollers guide vertical movement of the pressure plate. A panel slidable on the pressure plate is elfective in one position to close said opening. An expansible ring around the edge of the pressure plate makes sealing engagement with the ladle bearing plate when the pressure plate is raised. A bellows extending between the vessel cover and the pressure plate encloses the inlet in the cover.

3,523,684 Patented Aug. 11, 1970 BRIEF DESCRIPTION OF THE DRAWINGS A complete understanding of the invention may be obtained from the following detailed description and explanation which refer to the accompanying drawings illustrating the present preferred embodiment. In the drawings:

FIG. 1 is a plan View of the vessel cover and the pressure plate thereon with associated parts;

FIGS. 2 and 3 are vertical sections taken along the planes of lines IIII and III-III of FIG. 1, respectively; and

FIG. 4 is an elevation partly broken away, showing the ladle and vacuum vessel in cooperative relation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in detail to the drawings, a bottom-pour teeming ladle 10 is adapted to deliver molten metal to a vacuum vessel or bottle 11 having exhaust outlets 11a and 11b. Metal flows from the bottom of bottle 11, after being degassed therein, into a mold (not shown) therebelow. Vessel 11 is of plate construction, is lined with refractory and has a removable cover 12 sealed thereon. An inlet 13 is formed in the cover. A pressure plate 14 is liftably supported on cover 12 by cylinders and pistons 15 within a circle of centering guide rollers 16. Rollers 16 are journaled on posts 17 upstanding on cover 12.

Pressure plate 14 has an opening 18 therein alined with inlet 13. A refractory-lined pouring tube 20 extends downwardly therefrom through inlet 13. A neck 22 extends upwardly from cover 12, surrounding tube 20. A metallic bellows 23 encloses neck 22 and tube 20 and has its ends secured to pressure plate 14 and cover 12, respectively. Clamping rings 24 and 25 to which the ends of the bellows are secured, are'tightly fastened to the pressure plate and cover by screws. A telescoping sleeve 26 is fitted within bellows 23.

A marginal ring 27 extends around plate 14 and has a groove 28 in its upper face. An expansible tube 29 in the groove has a hose connection (not shown) to a source of fluid under pressure, for a purpose to appear shortly. A panel 30 is slidable on plate 14 between guides 31. The panel has an opening 32 therein adapted to aline with opening 18. In at least one position, how ever, the panel closes'opening 18. A fluid-pressure cylinder and piston 33 mounted radially on ring 27 actuate the panel between open and closed positions.

Ladle 10 has a nozzle 34 controlled by a sliding panel 35, as disclosed in Shapland Pat. No. 3,352,465. We mount a bearing plate 36 over the nozzle end on bolts 37 Welded to the ladle bottom. Plate 36 is sealed to the nozzle by a layer of refractory cement 38.

In using our improved vessel and ladle, assuming first that they are entirely disconnected, ladle 10 is free and may thereupon be taken to a melting furnace for filling. Meanwhile, on moving panel 30 to closed position, vessel 11 may be pumped down to the desired low pressure. When ready for teeming, ladle 10 is brought over the vessel, plate 14 is raised until ring 27 engages bearing plate 36 and ring 29 is inflated by admitting fluid under pressure, thereby establishing a gas-tight seal. Panel having been withdrawn, movement of panel 30 to open position permits metal to flow from ladle 10 to vessel 11 through tube 20, under the control of the ladle stopper rod, for effective degassing. When the ladle contents have been transferred to vessel 11, the panel 30 is restored to closed position, sealing ring 27 is relieved of fluid and ladle 10 is disconnected from the vessel. Gas under pressure may thereupon be admitted to vessel 11 above the level of metal therein, through a suitable connection (not 3 shown), to discharge metal from the vessel to the mold at the desired rate.

It will be apparent from the foregoing that our invention provides a vacuum vessel which may be pumped down to low pressure before the ladle is brought into position thereover and may subsequently make a gas-tight connection with the ladle. After the ladle has been emptied, furthermore, it may be disconnected and removed yet the vessel may be re-pressurized to control flow of metal therefrom.

Although we have disclosed herein the preferred embodiment of our invention, we intend to cover as well any change or modification therein which may be made with out departing from the spirit and scope of the invention as set forth in the claims.

We claim:

1. The combination with a ladle having a bottompour nozzle, a. closure therefor, and a bearing plate secured to the bottom of the ladle, surrounding said nozzle and sealed thereto, of a vacuum degassing vessel having a cover with an inlet therein, a pressure plate on said cover having an opening therethrough alined witlT said inlet, means guiding up and down movement of the pressure plate, means effecting such movement, a panel slidable on said pressure plate effective in one position to close said opening, an expansible ring extending peripherally of said pressure plate adapted to engage said bearing plate when the ladle is disposed to discharge metal into said inlet and said pressure plate is raised to sealing relation with said bearing plate, and a bellows extending 4 between and secured to the cover and the pressure plate, enclosing said inlet and said opening.

2. The combination as defined in claim 1 characterized by a refractory ring on said pressure plate alined with said opening, adapted to register with said nozzle.

3. The combination as defined in claim- 1 characterized by a refractory-lined tube extending downwardly from said pressure plate in alinement with said opening to said inlet.

4. The combination as defined in claim 3 characterized by a neck on said cover alined with said opening and extending upwardly therefrom.

5. The combination as defined in claim 1 characterized by. said guiding means being centering rollers on said cover spaced peripherally of said pressure plate.

6. The combination as defined in claim 1 characterized by said movement-effecting means being a plurality of fluid-pressure cylinders and pistons on said cover spaced circumferentially of said pressure plate.

References Cited UNITED STATES PATENTS 2,825,107 3/1958 Schueler 164--61 X 2,976,587 3/1961 Daussen 16465 3,163,897 1/1965 Sylvester 164-309 X 3,402,757 9/ 196-8 Halliday 164-66 3,298,680 1/1967 Jablin.

I SPENCER OVERHOLSER, Primary Examiner J. S. BROWN, Assistant Examiner

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