US3866665A

US3866665A - Twin strand continuous casting apparatus with a tundish load balancing vessel

Info

Publication number: US3866665A
Application number: US430032A
Authority: US
Inventors: Rudolf Schoffmann
Original assignee: Allis Chalmers Corp
Current assignee: Voestalpine AG
Priority date: 1974-01-02
Filing date: 1974-01-02
Publication date: 1975-02-18
Anticipated expiration: 1992-02-18
Also published as: CA1039923A

Abstract

A twin strand continuous metal casting apparatus is disclosed including two casting molds, a vertical arbor assembly, and a tundish carrier assembly mounted on the arbor with a pair of forks each carrying a tundish projecting radially outward from a common hub around the arbor. A tundish loading vessel is provided having a pair of discharge spouts projecting in opposite directions. A support is connected between the forks, which carry the tundish loading vessel transversely above the forks with each spout over one of the tundishes. A rocking mechanism is provided to rock the loading vessel for varying the rate of metal discharge through the two spouts to the two tundishes and equalize the load of molten metal in the two tundishes. The rocking assembly comprises linkages which automatically respond to unequal loading of the two tundishes and tilt the loading vessel to increase the flow of metal to the lesser loaded of the two tundishes.

Description

United States Patent [191 Schoffmann [4 1 Feb. 18, 1975 TWIN STRAND CONTINUOUS CASTING APPARATUS WITH A TUNDISI-I LOAD BALANCING VESSEL [75] Inventor: Rudolf Schoffmann, Linz, Austria [73] Assignee: Allis-Chalmers Corporation,

Milwaukee, Wis.

[22] Filed: Jan. 2, 1974 [2]] Appl. No.: 430,032

[52] US. Cl. 164/281, 164/337 [51] Int. Cl B22d 11/10, B22d 37/00 [58] Field of Search 164/281, 335, 337;

[56] References Cited UNITED STATES PATENTS 3,552,902 1/1971 Schoffmann et al 164/281 3,773,228 11/1973 Koch et al. 164/281 X FOREIGN PATENTS OR APPLICATIONS 701,189 12/1953 Great Britain 164/281 Primary Examiner Robert D. Baldwin Attorney, Agent, or FirmArthur M. Streich ABSTRACT A twin strand continuous metal casting apparatus is disclosed including two casting molds, a vertical arbor assembly, and a tundish carrier assembly mounted on the arbor with a pair of forks each carrying a tundish projecting radially outward from a common hub around the arbor. A tundish loading vessel is provided having a pair of discharge spouts projecting in opposite directions. A support is connected between the forks, which carry the tundish loading vessel trans versely above the forks with each spout over one of the tundishes. A rocking mechanism is provided to rock the loading vessel for varying the rate of metal discharge through the two spouts to the two tundishes and equalize the load of molten metal in the two tundishes. The rocking assembly comprises linkages which automatically respond to unequal loading of the two tundishes and tilt the loading vessel to increase the flow of metal to the lesser loaded of the two tundishes.

8 Claims, 5 Drawing Figures PATENTED FEB] 1 75 SHEET 10F 3 FM'ENTEU FEB 1 8 5 SHEET 2 OF 3 1 TWllN STRAND CONTINUOUS CASTING APPARATUS WITH-ll A TUNDISH LOAD BALANCING VESSEL CROSS REFERENCE TO RELATED PATENT I APPLICATION This application discloses an invention which may be applied and is herein disclosed as being applied, to a continuous casting apparatus which is the subject of my copending U.S. Pat. application entitled Continuous Casting Apparatus with Movable Ladles and Tundishes," Ser. No. 430,l95, filed concurrently with this application.

BACKGROUND or THE INVENTION 1. Field of the Invention This invention relates to a coontinuous casting of metals and in particular to a twin strand continuous casting apparatus with movable ladles and tundishes, and balanced metal flow to two casting molds. This invention further relates to improvements to apparatus such as disclosed in a prior patent to Anton Kubera and me, U.S. Pat. No. 3,552,902 ofJan. 5, 1971 and my aforesaid copending patent application.

2. Description of the Prior Art Twin strand continuous casting machines are known to those skilled in this technology. U.S. Pat. No. 2,804,665 discloses a twin strand caster having a single tundish with two orifices for discharging metal simultaneously or alternately to two casting molds. This tundish is rocked to provide unbalanced metal flow into the molds according to a predetermined cycle.

Prior art patents also disclose arrangements for supporting the great weight of ladles and tundishes, with apparatus including carriages having wheels or rollers engaging railway tracks to support the ladles and/or tundishes being moved into and away from casting positions. Examples of such arrangements are disclosed in U.S. Pat. No. 3,344,847, Oct. 3, 1967; U.S. Pat. No. 3,382,913, May 14, 1968; U.S. Pat. No. 3,446,269, May 27, 1969; and U.S. Pat. No. 3,456,713, July 22, 1969.

U.S. Pat. No. 3,552,902, Jan. 5, 1971, granted to Anton Kubera and me, discloses a pair of ladle carrier arms pivotally mounted on a common vertical arbor, and a pair of tundishes each separately pivotable about its own vertical support column, with each of the ladles and tundishes being movable into and away from casting positions.

U.S. Pat. No. 3,556,349 discloses a pair of tundishes mounted to pivot together on a single vertical arbor and which can be raised and lowered, but which will require separate support structure for one or more ladles.

My copending patent application, to which cross reference has been made, discloses ladles and tundishes mounted on a common central arbor assembly which requires no other support for moving the ladles and tundishes into and away from casting positions.

SUMMARY OF THE PRESENT INVENTION It is a feature of the present invention that a tundish carrier assembly is provided with a pair of tundishes carried by forks projecting radially outward from a common hub around an arbor, with a support connected between the forks which carries a tundish loading vessel transversely above the two tundishes for loading both tundishes with molten metal through a LII pair of discharge spouts, one over each tundish. The carrier assembly is pivotally mounted on the arbor to move both tundishes and their loading vessel in a horizontal plane as a single unit over two casting molds for casting twin strands of metal.

Another feature of the present invention is that the tundish loading vessel is mounted to rock on its support for varying the rate of dishcarge to the two tundishes, and with an axis of support moving as the loading vessel is tilted, to be beneath the center of gravity of the load of molten metal within the loading vessel.

Another feature of the invention is that a mechanism is provided which automatically responds to unequal loading of the two tundishes by tilting the loading vessel toward the lesser loaded of the two tundishes.

The objects of the invention comprise providing for the aforesaid features and with a compact single arbor assembly, support for moving the ladles, tundishes and tundish loading vessel into and away from casting position.

Other features and objects of the invention that have been attained will appear from the more detailed description to follow with reference to an embodiment of the invention shown in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 of the accompanying drawings show a side elevation, partly in section, a ladle and tundish support apparatus according to the present invention;

FIG. 2 is a top view of the apparatus shown in FIG. 1;

FIG. 3 is a view taken along line III-III in FIG. 1 and viewing the structure in the direction indicated by arrows;

FIG. 4 is a view in section taken along line IVIV in FIG. 2 and viewing the structure in the direction indicated by arrows; and

FIG. 5 is a fragmentary view in section taken along line VV in FIG. 2 and viewing the structure in the direction indicated by arrows.

DESCRIPTION OF THE [PREFERRED EMBODIMENT Referring to FIG. l and FIG. 2 of the drawing, an apparatus is shown for continuous casting of metal in a pair of casting molds 1 and la opening at or above a casting floor 2 shown in FIG. 1. The apparatus is provided with a central vertical arbor assembly 3 having an upper cylindrical column 4 telescopically arranged within a lower cylindrical column member 5 with column 4 projecting vertically upward from column 5. The column member 5 is secured, as by welding, to support structures 6 beneath the casting floor 2. column 5 has a circular bottom piece 7 also welded to support structure 6, and having a square central opening through which a square key 8 projects (see also FIG. 3) to provide alignment of the arbor assembly 3 relative to the support structure 6.

Column 4 is telescopically fitted within the upper and open end of column 5. One or more keys 10 are provided which are arranged in vertical parallel alignment with arbor 3, which are welded to the inner surface of column 5 and project into a vertical slot 111 defined in the outer surface of column 4, to lock column 4 against rotation while permitting vertical. movement of column 4 within column 5.

A pair of ladle carrier arms 14, are mounted on an upper portion of column 4 to carry a pair of ladles 16, 17. The

arms

14, 15 rest upon

thrust bearing collars

18, 19, respectively, that are secured to column 4. Antifriction roller bearings 22 are interposed between arm 14 and column 4, and antifriction roller bearings 23 are interposed between arm 15 and column 4, and thus both

arms

14, 15 are pivotable around column 4, each in a horizontal plane. The manner in which such pivotable movement is provided for will now be described. A nonrotating ring gear 25 is rigidly secured, as by welding, to the column 4 between

arms

14, 15. A reversible electric motor 26 is mounted on arm 14 with its drive shaft 27 projecting downwardly. A pinion gear 28 is mounted on drive shaft 27 and engages ring gear 25. When motor 26 turns shaft 27 and pinion gear 28, motor 26 and arm 14 pivot horizontally around column 4 because, as has been stated, ring gear 25 cannot turn as it is welded to column 4 and column 4 is held against rotation by the keys 10. Likewise, a reversible electric motor 29 is mounted on arm 15 but with its drive shaft projecting upwardly. A pinion gear 31 is mounted on drive shaft and also engages ring gear 25. When motor 29 turns its shaft 30 and pinion gear 31, motor 29 and arm 15 pivot horizontally around column 4. Electric power for

motors

26 and 29 may be delivered to

movable arms

14, 15 for the motors by such as brushes (not shown) engaging slip rings 32 on gear 25. Column 4,

arms

14 and 15, ladles 16, 17, ring gear 25, and

motors

26 and 29, are also shown in the top view of FIG. 2.

Referring again to FIG. 1, in addition to

arms

14, 15, and ladles 16, 17 being pivotable about the arbor assem bly 3, such arms anad ladles may also be raised and lowered. As shown in FIG. 1 the

arms

14, 15 are in their lowest position, with the thrust bearing collar 19 resting upon an annular cap 35 fastened to the top of the lower column 5. Column 4,

arms

14, 15 and ladles l6, 17 may be raised from the position shown in FIG. 1, and then lowered again, by a reversible lift mechanism 37 arranged within the lower column 5 and beneath the upper column 4. As shown in FIG. 3, the lift mechanism 37 may comprise several units (six are shown) each preferably comprising a cylinder defining block 38 containing a piston 39 actuated by hydraulic fluid pressure.

With reference again to FIG. 1, a pair of tundish carrier arms 40, 41 are mounted on an upper portion of the lower column 5. As shown in FIG. 2, arm carries a pair of tundishes 42, 42a and arm 41 carries a pair of tundishes 43, 43a. As shown in FIG. 1, the arms 40, 41 rest upon thrust bearing collars 44, 45, respectively, that are secured to column 5. Antifriction roller bearings 48 are interposed between arm 40 and column 5, and antifriction roller bearings 49 are interposed between arm 41 and column 5, and thus both arms 40, 41 are pivotable around column 5, each in a horizontal plane. The manner in which the pivotable movement of arms 40, 41 is provided for is similar to that which has been described for the arms l4, 15. That is, a nonrotating ring gear 51 is rigidly secured, as by welding, to the column 5 between arms 40, 41. a reversible electric motor 52 is mounted on arm 40 on the opposite side of column 5 from tundish 42. Motor 52 is arranged with its drive shaft 53 projecting downwardly. A pinion gear 54 is mounted on drive shaft 53 and engages ring gear 51. When motor 52 turns shaft 53 and pinion gear 54,

motor 52 and arm 40 pivot horizontally around column 5 because, as has been stated, ring gear 51 cannot turn as it is welded to column 5 and column 5 is held against rotation because it is welded to support structure 6. Likewise, a reversible electric motor 55 is mounted on arm 41 (on the opposite side of column 5 from tundish 43) but with its drive shaft 56 projecting upwardly. A pinion gear 57 is mounted on drive shaft 56 and also engages ring gear 51. when motor 55 turns its shaft 56 and pinion gear 57, motor 55 and arm 41 pivot horizontally around column 5. Electric power for motors 52 and 55 may also be delivered to movable arms 40, 41 for the motors by such as brushes (not shown) engaging slip rings 58 on gear 51.

In addition to arms 40, 41 and tundishes 41, 42a, 43, 43a being pivotable about the arbor 3, the tundishes may also be raised and lowered. The means for accomplishing this is identical for both tundish arms and therefore only tundish arm 40 will be described. Tundish carrier arm 40 comprises a hub assembly 60 mounted around the lower column 5 and as shown in FIG. 2 a pair

tundish supporting forks

61, 61a project radially outward from hub assembly 60. The

forks

61, 61a are connected together by a cross beam 61b and to the hub 60 for vertical movement relative to the hub 60. The hub 60 defines a pair of slots 62, 63. Only slot 62 can be seen in FIG. 1 but both slots 62, 63 are visible in the top view of FIG. 2. The fork cross beam 61b, as shown in FIG. 2, is provided with vertical guide bars 64 and 65 which project into slots 62, 63 to guide movement of beam 61b and

forks

61, 61a up and down relative to hub 60. The movement of beam 61b and

forks

61, 61a is provided for by winch means 67 shown in FIG. 1 as comprising a hydraulic fluid pressure operated cylinder 68 connected to hub 60 which operates to move a piston rod 69 up and down. A roller 70 is connected to the upper end of rod 69. A cable 71 is secured to hub 60, looped around roller 70 and a second roller 72, and cable 71 extends downwardly and is secured to

forks

61, 61a. Fork 61 is shown in FIG. 1 to be in its uppermost position. To

lower forks

61, 61a, rod 69 and roller 70 are moved upwardly and cable 71 moves over the second roller 72 clockwise, as shown, as gravity moves

forks

61, 61a downwardly. To raise

forks

61, 61a again, rod 69 and roller 70 are moved downwardly to pull cable 71 counterclockwise over the second roller 72 and

forks

61, 61a are pulled upwardly. Thus

forks

61, 61a and tundishes 42, 42a can be raised and lowered relative to the arbor assembly 3 and relative to ladles 16, 17.

A tundish loading vessel 75 is shown in FIG. 1 as being arranged over tundish 42 and beneath ladle 16. The vessel 75 will be described further with reference to FIG. 2 and FIG. 4. The vessel 75 has a pair of discharge spouts 76, 77 projecting from opposite sides of the vessel 75 and as shown in FIG. 4, vessel 75 may also be provided with a cover 78 having a single entrance port 79.

Support means 80 will'now be described with reference to- FIG. 4, which carry vessel 75 transversely above the

forks

61, 61a with spout 76 over tundish 42 and spout 77 over tundish 42a. The support means 80 comprise a cross beam 81 connected between

forks

61, 61a,

vertical posts

82, 83 mounted on beam 81, and a table 84 connected to

posts

82, 83 in a position above beam 81. Means to accommodate rocking or tilting support of vessel 75 are interposed between the vessel 75 and table 84, which comprise an arcuate gear segment 85 secured, as by welding, to the bottom of vessel 75, and a planar gear rack 86 mounted on the table 84. The tops of

posts

82, 83 project upwardly from table 84 toward

notches

87, 88 formed in gear segment 85, to provide for limiting the angle through which vessel 75 can tilt in either direction.

Means to rock or tilt the tundish loading vessel 75 on the support means 80 comprise a pair of balance assemblies 90, 91. Since the balance assemblies 90, 91 are identical, only assembly 90 shall be described in detail. The balance assembly 90 comprises (see FIG. 5) a first linkage 92 and a second linkage 93.

With reference to FIG. 5, the first linkage 92 comprises a fluid pressure operated axially expandable motor 95 connected on one end by a pivot 96 to fork 61, for pivotal movement in a vertical plane, and has a piston rod 97 projecting from motor 95 which is pivotally connected to a cross arm 98 intermediate the ends of cross arm 98. A lower end 99 of arm 98 is pivotally connected to a frame 100 that rests on an end piece 101 of the second linkage 93. An upper end 102 of arm 98 engages a hook 103 attached to the radially inner end of tundish 42. Arm 98 makes contact with tundish 42 as shown in phantom lines. Piston rod 97 is then moved toward pivot 96 and the upper end 102 of cross arm 98 engages hook 103 and lifts the radially inner end of tundish 42 off fork 61 and the weight of tundish 42 (and its load of molten metal) then causes frame 100 to bear downwardly on end piece 101 of the second linkage 93, with a force depending upon the load within tundish 42. The piece 101 is mounted on an arm 105 of the second linkage 93. The arm 105 is connected by a pivot 106 to a member 107 which is in turn rigidly attached to fork 61. Referring now to FIG. 4 the end of arm 105 remote from piece 101 carries a roller 109 which engages a push rod 110. Push rod 110 is axially and vertically slidable in a sleeve 111 attached to cross beam 81. Push rod 110 projects upwardly from cross beam 81 and table 84 to engage the bottom of tundish loading vessel 75. Sleeve 110 is mounted on beam 81 at a location between a first vertical plane XX projecting radially from arbor 3 through the centerline of vessel 75, and a second plane Y-( projecting radially from arbor 3 through spout 76.

In the operation of the balance system, the downward force on piece 101 resulting from the weight of tundish 42 and the load of metal therein, is transmitted as an upward force to the bottom of tundish loading vessel 75. Since balance assemblies 90 and 91 are identical, except that assembly 91 is on the opposite side of plane X-X from assembly 90, when tundishes 42, 42a are equally loaded with molten metal the assemblies 90 and 91 transmit equal and balanced forces and vessel 75 remains horizontal and discharging metal equally to both tundishes 42, 42a. However if, for example, tundish 42 carries a greater load of metal than tundish 42a, the balance assembly will transmit a greater force through push rod 110 to vessel 75 than is transmitted to vessel 75 by balance assembly 91, and vessel 75 will then tilt toward tundish 42a, as shown with phantom lines in FIG. 4, until the accelerated flow to tundish 42a due to tilting vessel 75, restores equal loading in the two tundishes 42, 42a.

1n the operation of the entire apparatus, with reference to FIG. 2, a pair of tundishes, for example tundishes 42, 42a, are positioned over the molds 1, 1a.

Ladle carrier arm 14, with ladle 16 filled with molten metal, may then be pivoted counterclockwise around column 4 until ladle 16 is over tundish loading vessel 75. The vertical position of ladle 16 may be adjusted by the lift mechanism 37 and the vertical position of tundishes 42, 42a and vessel may be adjusted as desired by the winch means 67. The pouring may then begin. When ladle 16 is almost empty, ladle l7 filled with molten metal will be pivoted clockwise around column 4 to a position alongside ladle 16. When ladle 16 is empty, ladle 16 will be pivoted clockwise away from vessel 75 and ladle 17 is pivoted clockwise to a position over tundish loading vessel 75. Tundish loading vessel 75 and tundishes 42, 42a have sufficient capacity that they do not empty during the brief time required to move ladle 16 out of the way and ladle 17 into position over the tundish loading vessel 75. The empty ladle 16 will be pivoted clockwise to a refill position on the opposite side of arbor 3 from molds 1, 1a. When ladle 16 is refilled it will be pivoted counterclockwise to a position alongside ladle 17 and when ladle 17 is empty it will be moved counterclockwise to the refill position and ladle 16 will be moved counterclockwise over tundish loading vessel 75. When the tundish loading vessel 75 and tundishes 42, 42a are to be taken out of operation, casting is interrupted briefly as arm 40 is turned clockwise around the arbor assembly 3 to make room for arm 41 to turn clockwise and locate tundish loading vessel 75a and tundishes 43, 43a over molds 1, 1a. Arm 40 continues to turn clockwise until arriving at a suitable position for lowering

forks

61, 61a to lower tundishes 42, 42a on suitable carriage means (not shown). New or refurbished tundishes may then be moved over

forks

61, 61a and

forks

61, 61a raised to lift and carry the new or refurbished tundishes, when needed, over molds 1 and 1a. Additionally, the vertical adjustability of forks 61, 6111 as well as hub 60 and the

ladle arms

14, 15 can be utilized to provide improved access to various parts of the apparatus to facilitate inspection and maintenance work.

With a pair of tundishes such as 42, 42a and a tundish loading vessel such as 75, in position over molds 1, 1a, molten metal is poured from a ladle 16 or 17, through port 79 into vessel 75. The tundish loading vessel 75 discharges molten metal through both spouts 76, '77 to the tundishes 42, 42a. The tundish loading vessel 75 with its arcuate gear segment may be rocked or tilted on the planar gear rack 86 and the load applied to gear rack 86 moves as vessel 75 and the arcuate gear rocks thereon, to a location that is always beneath the center of gravity of the charge of molten metal within vessel 75, and thus the metal charge itself produces no unbalanced forces on the support means 80. Furthermore, the rocking or tilting of the tundish loading vessel 75 when the tundishes 42, 42a are unequally loaded, occurs automatically as the balance assemblies 90, 91 operate to tilt the vessel as required to restore balanced loading of the tundishes.

The foregoing is accomplished with an apparatus that utilizes only a single vertical arbor assembly to support and move ladles, tundish loading vessels and tundishes as required for such operations and purposes as have been described, and thus it has been shown how the features and objects of the present invention have been attained in a preferred manner. However, modification and equivalents of the disclosed concepts such as readily occur to those skilled in the art are intended to be included in the scope of this invention. Thus, the scope of the invention is intended to be limited only by the scope of the claims such as are or may hereafter be, appended hereto.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A twin strand continuous metal casting apparatus comprising:

a. two casting molds spaced apart in a common horizontal plane;

b. a vertical arbor assembly horizontally spaced from both molds;

c. a tundish carrier assembly mounted on the arbor for pivotal movement in a horizontal plane above the molds, said assembly having a hub around the arbor and a pair of forks projecting radially outward from the hub in a common horizontal plane;

d. a plurality of tundishes, with one tundish mounted on each fork;

e. a tiltable tundish loading vessel having a pair of discharge spouts projecting from opposite sides of the vessel;

f. vessel supporting means connected between said forks and carrying the tundish loading vessel transversely above the forks with each of the spouts over one of the tundishes; and

g. ladle supporting means adapted to carry a ladle containing molten metal and operative to move a ladle of molten metal into a teeming position over the tundish loading vessel to discharge metal thereto for selective flow through both said spouts to both said tundishes.

2. An apparatus according to claim 1 having an arcuate gear segment mounted on the bottom of the tundish loading vessel above the vessel supporting means and having gear teeth projecting downwardly therefrom, a

planar gear rack mounted on the vessel supporting means having gear teeth engaging the teeth of the arcuate gear segment, and rocking means connected to the tundish loading vessel constructed and arranged to tilt the tundish loading vessel and arcuate gear on the supporting means and planar rack gear for varying the rate of metal discharge from the loading vessel through said spouts to said tundishes.

3. An apparatus according to claim 2 with said rocking means having a pair of balance assemblies each comprising:

a. a first linkage connected on one end to a radially inner portion of said fork and with a second end thereof being adapted to engage a radially inner end of the tundish on said fork for lifting the radially inner end of the tundish upwardly from its supporting fork;

b. a second linkage carried by said fork and having a first end engaging the second end of the first linkage, and a second end engaging the bottom of the tundish loading vessel at a location between a first vertical plane projecting radially from the arbor through the center of the vessel and a second vertical plane projecting radially from the arbor through the vessel spout above the tundish engaged by the first linkage, with said second linkage being operative to transmit downward force applied thereto by the first linkage as an upward lifting force to the bottom of the tundish loading vessel; whereupon the pair of balance assemblies respond to unequal loading of the two tundishes and tilt the tundish loading vessel toward the lesser loaded tundish to increase the flow of molten metal from the loading vessel to the lesser loaded of the two tundishes and decrease the flow of molten metal from the loading vessel to the greater loaded of the two tundishes until a balanced loading of the two tundishes is restored.

4. An apparatus according to claim 3 in which the first linkage comprises:

a. a fluid pressure axially expandable motor connected on a first end to said fork for pivotal movement in a vertical plane b. a cross arm in a vertical plane connected intermediate the ends thereof to a second end of the expandable motor, said cross arm having a lower end connected to a pivot carried by the first end of the second linkage, and said cross arm having an upper end engageable with said tundish for lifting the radially inner end of the tundish off the fork when said motor pivots the cross arm about the pivot at the lower end of said cross arm, to thus apply the downward force of tundish loading to the first end of the second linkage.

5. An apparatus according to claim 1 in which said i ladle supporting means comprise first and second carrier arms mounted in vertically spaced arrangement on an upper portion of the arbor assembly above the tundish carrier assembly for independent pivotal movement of said arms relative to said arbor and each other in a horizontal plane.

6. An apparatus according to claim 5 in which the tundish carrier assembly comprises third and fourth carrier arms mounted in vertically spaced arrangement on the arbor assembly for independent pivotal movement of the third and fourth arms relative to the arbor assembly in a horizontal plane, and with each of the tundish carrier arms having a pair of forks for carrying tundishes and a said tundish loading vessel above each pair of tundishes.

7. An apparatus according to claim 5 in which:

a. the vertical arbor assembly comprises telescoping upper and lower column members with the lower column adapted to be rigidly attached to support structure and the upper column projecting upwardly from and movable relative to the lower column;

b. the first and second ladle carrier arms are mounted in vertically spaced arrangement on the upper column for independent pivotal movement of said arms relative to said upper column in a horizontal plane;

0. a vertically arranged key attached to one of said column members and projecting into an elongated vertical slot defined in the other of said column members to limit movement of the upper column to vertical movement; and

d. a reversible lift mechanism between the telescoping column members for lifting and lowering the upper column and both of the ladle carrier arms relative to the tundish loading vessel.

8. An apparatus according to claim 6 in which the third and fourth arms are each constructed with the pair of forks connected to the hubs thereof by a winch mounted on the hub having a cable connected to the forks for raising and lowering the pair of forks, the tundish loading vessel supporting means, and the tundish loading vessel relative to the ladle carrier arms and the two casting molds.

Claims

1. A twin strand continuous metal casting apparatus comprising: a. two casting molds spaced apart in a common horizontal plane; b. a vertical arbor assembly horizontally spaced from both molds; c. a tundish carrier assembly mounted on the arbor for pivotal movement in a horizontal plane above the molds, said assembly having a hub around the arbor and a pair of forks projecting radially outward from the hub in a common horizontal plane; d. a plurality of tundishes, with one tundish mounted on each fork; e. a tiltable tundish loading vessel having a pair of discharge spouts projecting from opposite sides of the vessel; f. vessel supporting means connected between said forks and carrying the tundish loading vessel transversely above the forks with each of the spouts over one of the tundishes; and g. ladle supporting means adapted to carry a ladle containing molten metal and operative to move a ladle of molten metal into a teeming position over the tundish loading vessel to discharge metal thereto for selective flow through both said spouts to both said tundishes.

2. An apparatus according to claim 1 having an arcuate gear segment mounted on the bottom of the tundish loading vessel above the vessel supporting means and having gear teeth projecting downwardly therefrom, a planar gear rack mounted on the vessel supporting means having gear teeth engaging the teeth of the arcuate gear segment, and rocking means connected to the tundish loading vessel constructed and arRanged to tilt the tundish loading vessel and arcuate gear on the supporting means and planar rack gear for varying the rate of metal discharge from the loading vessel through said spouts to said tundishes.

3. An apparatus according to claim 2 with said rocking means having a pair of balance assemblies each comprising: a. a first linkage connected on one end to a radially inner portion of said fork and with a second end thereof being adapted to engage a radially inner end of the tundish on said fork for lifting the radially inner end of the tundish upwardly from its supporting fork; b. a second linkage carried by said fork and having a first end engaging the second end of the first linkage, and a second end engaging the bottom of the tundish loading vessel at a location between a first vertical plane projecting radially from the arbor through the center of the vessel and a second vertical plane projecting radially from the arbor through the vessel spout above the tundish engaged by the first linkage, with said second linkage being operative to transmit downward force applied thereto by the first linkage as an upward lifting force to the bottom of the tundish loading vessel; whereupon the pair of balance assemblies respond to unequal loading of the two tundishes and tilt the tundish loading vessel toward the lesser loaded tundish to increase the flow of molten metal from the loading vessel to the lesser loaded of the two tundishes and decrease the flow of molten metal from the loading vessel to the greater loaded of the two tundishes until a balanced loading of the two tundishes is restored.

4. An apparatus according to claim 3 in which the first linkage comprises: a. a fluid pressure axially expandable motor connected on a first end to said fork for pivotal movement in a vertical plane b. a cross arm in a vertical plane connected intermediate the ends thereof to a second end of the expandable motor, said cross arm having a lower end connected to a pivot carried by the first end of the second linkage, and said cross arm having an upper end engageable with said tundish for lifting the radially inner end of the tundish off the fork when said motor pivots the cross arm about the pivot at the lower end of said cross arm, to thus apply the downward force of tundish loading to the first end of the second linkage.

5. An apparatus according to claim 1 in which said ladle supporting means comprise first and second carrier arms mounted in vertically spaced arrangement on an upper portion of the arbor assembly above the tundish carrier assembly for independent pivotal movement of said arms relative to said arbor and each other in a horizontal plane.

7. An apparatus according to claim 5 in which: a. the vertical arbor assembly comprises telescoping upper and lower column members with the lower column adapted to be rigidly attached to support structure and the upper column projecting upwardly from and movable relative to the lower column; b. the first and second ladle carrier arms are mounted in vertically spaced arrangement on the upper column for independent pivotal movement of said arms relative to said upper column in a horizontal plane; c. a vertically arranged key attached to one of said column members and projecting into an elongated vertical slot defined in the other of said column members to limit movement of the upper column to vertical movement; and d. a reversible lift mechanism between the telescoping column members for lifting and lowering the upper column and both of the ladle carrier arms relative to the tundish loading vessel.