WO2009054826A1

WO2009054826A1 - Downender transport table assembly for use in continuous casting plants

Info

Publication number: WO2009054826A1
Application number: PCT/US2007/022579
Authority: WO
Inventors: Steven Spencer; Paul D. Gilman
Original assignee: Loma Machine, A Division Of Magnum Integrated Technologies Inc.
Priority date: 2007-10-24
Filing date: 2007-10-24
Publication date: 2009-04-30

Abstract

A downender transport table assembly (20) is used in a continuous casting plant (10) to engage and support lengths of a continuously vertically cast metal slab (14) for transport and/or further processing. The transport table assembly includes a movable table (50) positionable between vertical and horizontal orientations. A shuttle carriage (82) is movable relative to the table (50) between an initial position spaced proximate to a mould outlet (35), and an end position moved therefrom. In use, the table (50) is oriented in a vertical position beneath the mould outlet (35) with the shuttle (80) in the raised start position. As the slab (14) is cast, its initial engagement with the shuttle carriage (82) results in the shuttle moving downwardly relative to the table (50) at substantially the same rate as the casting rate, providing a counterbalancing force on the slab (24). Once the shuttle carriage (82) moves to the lowered end position, a cut-off saw (34) severs the cast length of slab (24) into an individual billet. The table (50) is then reoriented to the horizontal position with the severed billet (24) thereon. Once so positioned, the shuttle carriage (82) is returned to its initial position, sliding the severed billet (24) from the table (50) for further processing.

Description

DOWNENDER TRANSPORT TABLE ASSEMBLY FOR USE IN CONTINUOUS CASTING PLANTS

SCOPE OF THE INVENTION

The present invention relates to a transport table assembly for use in continuous casting plants, and more particularly a downender transport table assembly for use with a casting machine operable to continuously vertically cast metal slabs. The transport table is provided to support the metal slab as it is cast vertically, and thereafter reposition cut lengths or billets severed from the slab in a generally horizontal orientation, for conveyancing and/or further processing within the plant.

BACKGROUND OF THE INVENTION

Various production systems have been developed for the continuous vertical casting of metal slabs. Typically, in a conventional continuous casting plant, a furnace is used to melt and supply molten metal to a tundish. The tundish in turn feeds the molten metal to a mould cavity having a lowermost discharge outlet opening. The discharge opening is formed with a profile corresponding to that of the desired cast slab or strip to be produced, such that the metal solidifies to assume a metal slab or strip profile corresponding to that of the mould opening. As the molten metal flows through the mould cavity, it is drawn outwardly from the discharge opening by pinch rolls.

Conventional continuous casting plants used in the vertical casting of non-ferrous metal strips, such as that described in United States Patent No. 7,004,236 B2 to Ostlund et al, include a cooling system as part of the mould cavity. The cooling system operates to cool the strip as it moves outwardly from the mould. In this manner, the cooled strip may thereafter be immediately wound or spooled for storage and/or transport.

Vertical casting of thicker metal sheets, strips or metal slabs, such as those having a thickness of 1 mm or greater (hereinafter collectively and generally referred to as slabs), has however, proven more difficult. As a result of the increased slab thickness, it is not possible to directly coil the formed slab for subsequent storage. Rather, a saw is provided to periodically cut the cast slab into pre-selected lengths or billets. The cut billets are then transported to other plant stations, such as grinding, polishing or rolling stations, for further processing.

The continuous vertical casting of thicker metal slabs made of softer non-ferrous metals, such as copper and copper alloys, presents a unique challenge. The thicker slab thicknesses result in increased heat retention within the cast slab, resulting in greater ductility as the slab moves from the mould outlet. As a result, unless the slab is adequately supported as it moves vertically, the slab may slip from the pinch rolls. In addition, until adequately cooled, the severed slab lengths or billets may have an increased susceptibility to bending, twisting or marring, adversely affecting slab quality and/or suitability for subsequent processing.

SUMMARY OF THE INVENTION

To at least partially overcome at least some of the foregoing difficulties, the present invention provides a downender transport table assembly for use with a casting plant, and preferably a casting plant for continuously casting a metal slab. The table assembly is operable to support a metal slab as it is vertically cast and/or transported for further processing. The transport table assembly includes a table which includes a surface having a size and shape selected to adequately support a desired length of cast slab. The table is movable so that the slab supporting surface is positionable between generally vertical (ie. 90° ± 20°) and generally horizontal (ie. 0° ± 30°) orientations. A shuttle carriage is movable relative to the table between an initial position spaced proximate to one table end and an end position moved remote therefrom.

In use, the table is initially oriented with the slab supporting surface generally aligned with a side of the mould outlet and with the shuttle carriage moved to the initial position. As the slab is cast, its initial engagement with the shuttle results in the shuttle carriage moving towards the end position. Most preferably, where the transport table assembly is used with casting plants operable to vertically cast metal slabs, the table is initially oriented in a generally vertical position with the shuttle carriage moved towards the upper oriented end. As the shuttle carriage is engaged by the slab, it moves downwardly relative to the table and most preferably at substantially the same rate as the slab casting rate, providing a counterbalancing force on the slab. Once the shuttle carriage moves to the end position, a cut-off saw, laser or other device severs the cast length of slab into an individual cut slab length. The table is then oriented in horizontal discharge position with the severed billet thereon. The shuttle carriage may then be returned to its initial position, sliding the severed billet from the table for further processing.

Another object of the invention is to provide an improved transport assembly for use with a continuous casting plant which is operable to vertically cast metal slabs, and which facilitates the transport and/or repositioning of slab billets while minimizing surface distortions and/or bending.

Another object of the invention is to provide a downender transport table assembly for use with continuous casting machines, which is operable to transport severed lengths or billets of a continuously cast non-ferrous metal slab in movement from an initial generally vertical orientation during casting, to a generally horizontal orientation for further conveyancing or processing.

A further object of the invention is to provide a continuous casting plant for the continuous vertical casting of metal slabs having a thickness of between about 50 mm and 300 mm, preferably 50mm and 250 mm, and most preferably between about 100 mm and 220 mm, and which includes a slab transport table assembly operable to support at least part of the slab during casting and/or transport to minimize slab damage.

In a simplified construction, the present invention provides a transport table assembly for use in a continuous casting plant and which is operable to support and transport and/or reposition cast sheets or slabs having a thickness of greater than about 50 mm, preferably between about 50 mm and 300 mm, and most preferably between about 100 mm and 220 mm, while minimizing deformation of the slab. Most preferably the casting plant includes a continuous casting machine which is operable to vertically cast metal slabs, and preferably slabs made of non-ferrous metals such as copper or copper alloys. As with typical metal casting plants, a tundish is provided for receiving molten metal from a furnace, and for retaining a volume of molten metal therein. A mould cavity having a downwardly open mould opening is positioned to substantially continuously receive molten metal from the tundish, and from which the metal strip or slab is vertically cast. Most preferably, the mould opening is configured to continuously cast the metal slab along a vertical casting axis downwardly through a pair of pinch rolls at a rate of between about 1 and 30 cm per minute, and preferably about 5 to 10 cm per minute, depending on the desired slab thickness.

A downender transport table assembly is provided to engage and support a portion of the cast slab as it moves vertically from the mould. The transport table is further operable to convey successive cut lengths of the slab which are severed into individual cut slab lengths or billets to outfeed conveyors for transport and/or further processing. The transport table assembly includes a movable table which has a surface having a length and width selected to support a pre-selected desired length of the slab. The table is movable such that the table surface is positionable between a generally vertical infeed orientation beneath the mould opening of 90°±20°, preferably 90°±3°; and a generally horizontal discharge orientation of 0°±25°, preferably 0°±5°. Although not essential, most preferably when in the generally horizontal orientation, the table surface is substantially aligned with the infeed end of an exit or other conveyor used in the transport of the slab billets to other work stations within the plant.

A shuttle carriage is provided which is selectively movable relative to the table surface. When the table surface is positioned in the generally vertical orientation, the shuttle carriage is most preferably initially moved upwardly towards a proximal uppermost raised end of the table, in a position adjacent the mould outlet opening. Most preferably, the shuttle carriage is sized so as to be engageable by a lower end of the cast slab as it moves vertically downward. While so engaged, as the slab is cast vertically, the shuttle is lowered while at least intermittently maintaining contact with the slab. Preferably, the shuttle carriage provides an upward counterforce on the cast slab to minimize the chance of its slipping out of the pinch rolls under its own weight. In a most preferred construction, following its initial engagement with the slab, the shuttle assembly is moved downward relative to the table surface to the distal lowermost positioned table end at substantially the same rate at which the metal slab is cast. The contact between the shuttle carriage and slab is maintained so as to continuously provide an upward force on the slab, minimizing the possibility that the slab may slip out of the pinch rolls under its own weight as it moves outwardly from the mould.

A cut-off saw or other cutting member is provided to successively cut off predetermined lengths of the slab into individual billets when the shuttle carriage moves to a pre-selected lowered position spaced towards the distal table end. Most preferably, the cut-off assembly is positioned in a location selected between the mould outlet opening and the position assumed by the uppermost proximal end of the table when in the vertical orientation.

Following the severing of each discrete cut slab length, the table is then moved to reposition the table surface in the horizontal outfeed orientation. This repositioning reorients the billet thereon into generally horizontal alignment with the exit or next conveyor. The table may be provided for movement by means of electric, hydraulic or pneumatic lift mechanisms so as to pivot and/or swing between vertical and horizontal positions. In a simplified construction, however, the table is movable along a series of guide tracks so as to be movable by means of a cable drive mechanism incorporating an electric motor and winch and pulley system. Once so aligned, the shuttle carriage is returned to its initial position adjacent to the proximal end of the table. The return movement of the shuttle assembly slides the severed slab length therewith, from the transport table surface horizontally onto the next infeed conveyor for further processing. Following the return of the shuttle conveyor to its initial position, the table is then returned to reorient the table surface in its generally vertical initial feed position, beneath the mould outlet opening.

In a most preferred construction, the transport table assembly is provided in pit- type continuous casting plant which includes a casting machine operable to cast the metal slab vertically into a downwardly extending pit. In such an arrangement, the table is movable into and outwardly from the pit. Most preferably, the table moves between the infeed and discharge positions along a guide track or ramp, and most preferably along one or more slides or guide rails.

Accordingly, in one aspect the present invention resides in a transport table assembly for use with a casting machine operable to vertically cast a metal slab, the assembly including,

a movable table having a slab support surface extending in a longitudinal direction from a first end to a second end, the support surface having a length and width selected to support a length of said slab thereon,

a shuttle carriage engageable with an end portion of the metal slab and being selectively movable in the longitudinal direction relative to said support surface between a first position moved towards said first end and a second position moved towards the second end, a shuttle drive for selectively moving the shuttle carriage between the first and second positions,

a guide track for guiding said table in movement between a first feed position with the support surface of the table is positioned in a generally vertical orientation generally aligned with said length of slab as it is initially cast from said machine, and a second discharge position wherein said support surface is moved at an angle relative to said feed position to engage and support a side of said metal slab, and whereby with the table in the discharge position, the shuttle drive is actuable to move the shuttle carriage to the first position to slide the length of slab from the table support surface, and

a table drive for selectively moving said table between said feed and discharge positions.

In another aspect the present invention resides in a transport table assembly for use with a vertical casting machine operable to substantially continuously cast a metal slab, the assembly including,

a transport table having a support surface extending in a longitudinal direction from a first end to a second end, a shuttle carriage configured for engaging contact with an end of said metal slab, the shuttle carriage being selectively movable in the longitudinal direction relative to the support surface between a first position spaced towards the first end and a second position spaced towards the second end,

a shuttle drive being operable to selectively move the shuttle between the first and second positions,

a guide track for guiding said table in movement between a feed position wherein said support surface is provided in a generally vertical orientation and a discharge position wherein said support surface is moved to a substantially horizontal position, and

In a further aspect the present invention resides in combination a transport table assembly and continuous casting machine, the continuous casting machine including a mould outlet for substantially continuously casting a metal slab vertically therethrough,

the table assembly including,

a movable transport table having a support surface extending in a longitudinal direction from a first end to a second end,

a guide track assembly for guiding said table in movement between a feed position wherein said support surface is provided in a generally vertical orientation substantially aligned with the casting axis and with said first end spaced proximate to said mould outlet, and a discharge position wherein said support surface is moved to a substantially horizontal position,

a table drive for selectively moving said table between said feed and discharge positions,

a shuttle carriage configured for engaging contact with an end of said cast slab, the shuttle carriage being selectively movable in the longitudinal direction relative to the support surface from a first position spaced towards the first end to a second position spaced towards the second end as the slab is continuously cast, whereby the engagement between the end of the cast slab and the shuttle carriage at least partially supports the slab during casting to reduce the possibility of slab slippage, as for example from pinch rolls,

a shuttle drive operable to selectively position the shuttle carriage in said first position with said table initially moved to the feed position.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference may now be had to the following detailed description taken together with the accompanying drawings in which:

Figure 1 illustrates a schematic side view of a continuous casting plant used in the vertical casting of non-ferrous metal slabs, and which incorporates a downender transport table assembly in accordance with a preferred embodiment of the invention;

Figure 2 illustrates a schematic end view of the continuous casting plant of Figure 1;

Figure 3 illustrates schematically an enlarged perspective top view of the transport table used in the downender transport table assembly of Figure 1 ;

Figure 4 illustrates a perspective side view of the transport table shown in Figure 3;

Figure 5 illustrates a perspective end view of the transport table shown in Figure 3; and

Figure 6 illustrates an enlarged perspective side view of the guide track assembly used in the downender transport table assembly shown in Figure 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENETS Figures 1 and 2 illustrate a continuous casting plant 10 which as will be described is operable to continuously vertically cast a copper or copper alloy metal slab 14 along a vertical casting axis A_v-A_v downwardly into a casting pit 16 which extends between about 10 and 25 metres into the plant floor 17. The plant 10 includes a casting machine 18 used to form the slab 14 from molten metal, and a downender transport table assembly 20. As will be described, the downender transport table assembly 20 is operable to reposition and transport individual severed slab lengths or billets 24 from the pit 16 and onto a horizontally oriented outfeed or exit conveyor 22. The exit conveyor 22 in turn is used to horizontally transport the severed metal billets 24 to subsequent grinding or turnover inspection station 27for further processing within the plant 10.

As shown in Figure 2, the continuous casting machine 18 includes a furnace 30, tundish 31, mould 32, pinch roll 33, and a flying cut-off saw 34. The furnace 30 is used to continuously melt and supply molten copper to the tundish 31 in a conventional manner. The tundish 31 is provided in communication with the mould 32. The mould 32 in turn includes a lower outlet opening 35 through which the slab 14 is cast. The pinch roll 33 withdraws newly formed slab 14 from mould 32 substantially continuously moving the slab 14 downwardly along a casting axis Ay- Ay. Most preferably, the outlet opening 35 has a profile selected to form the slab 14 with a thickness of between about 50 and 250 mm, and most preferably between about 100 and 220 mm. In this manner, as molten copper is fed via the tundish 31 into the mould 32, the slab 14 is continuously cast and drawn downwardly by the pinch rolls 33 into the pit 16, moving along the casting axis A_v-A_v at a casting rate selected at between about 1 and 20 cm per minute, and most preferably about 5 and 12 cm per minute.

Figure 1 illustrates the casting pit 16 as defined by opposing pairs of sidewalls 44a,44b extending downwardly below the plant floor 17, to a pit bottom 42. It is to be appreciated that the overall depth of the pit 16 will be selected having regard to the maximum length of severed or cut slab length 24 to be produced in the plant 10. Typically, each pair of sidewalls 44a,44b are provided with a lateral spacing of between about 3 and 4 metres and a length in a longitudinal direction of about 5 metres, again depending on the desired manufacturing capacity of the plant 10 and width of the slab 14.

Figure 6 illustrates best an access shaft 46 as extending into the sidewall 44a. As will be described, the access shaft 46 is provided with a height and width selected to enable the movement of the cut slab length 24 from a vertical position in the pit 16 aligned with the axis Av-Av, to a horizontal position displaced therefrom, and aligned with the exit conveyor 26. The floor 47 of the access shaft 46 extends angularly downwardly from the plant floor 17 adjacent the exit conveyor 26 at an angle of approximately 45°, to intersect the sidewall 44a approximately halfway between the pit bottom 42 and the mould outlet opening 35.

Figure 1 illustrates the transport table assembly 20 as including a table 50, a shuttle carriage assembly 80 and a guide track assembly 100. As shown best in Figures 3 to 5, the table assembly 50 includes a movable table 54 having a support surface 56, and a table drive system 58 (Figure 1). Figure 4 shows best the table 50 as further including forward and rearward support legs 60,62 which extend normal to the support surface 56. The forward support legs 60 extend downwardly from a proximal end 51 of the table 50 a distance D₁. The rearward support leg 62 is shorter than the support leg 60 and extends from the surface 56 a distance D₂. Pairs of wheels 64,66 are respectively rotatably secured to each end of the legs 60,62, with the wheels 66 of the rear support legs 62 being spaced laterally outwardly relative to the wheels 64 of the front support leg 60.

As shown best in Figure 3, most preferably the support surface 54 of the table 50 is elongated in a longitudinal direction extending from the first proximal end 51 to a second distal end 52 remote therefrom. The support surface 56 may further optionally include a series of longitudinally spaced rollers 74. The rollers 74 are advantageously used to movably support the cast slab 14, each cut slab length 24 and severed therefrom in casting operations.

As will be described, the table 50 is mounted for movement along a guide track assembly 100 by way of the table drive 58 so as to be movable between an initial infeed position shown in solid lines in Figure 1 and the discharge position shown in phantom. In the infeed position, the table 50 is positioned within the pit 16 with the support surface 56 of the table positioned at an angle of 0°±3° and generally aligned with the vertical axis Av-Av. In the discharge position, the table 50 is moved from the pit 16 with the support surface 56 horizontally aligned with and adjacent to an infeed end of the exit conveyor 26. In a most simplified construction, the table drive 58 consists of a wire cable 68 and a reversible electric winding motor 70 positioned above the plant floor 17 adjacent to the access shaft 46. The free end of the cable 68 is secured towards the distal end 52 of the table 50. In this manner, the winding or unwinding of the cable 68 about the winding shaft of the motor 70 may be used to selectively raise or lower the table 50 from and into the pit 16 along the access shaft 46.

The shuttle carriage assembly 80 is shown best in Figures 3 and 5 as including a shuttle carriage 82, side rails 84a,84b, a carriage drive 86 and sensors 88,90. Each of the side rails 84a,84b are mounted to a respective longitudinal side of the table 50, extending substantially the length thereof.

Figure 5 shows best the shuttle carriage 82 as spanning laterally the width of the table 50 and defining a central support socket 92. The support socket 92 is open towards the proximal end 51 of the table 50 and is formed with an interior profile which is complementary to that of the mould outlet opening 35, as well as the profile of the cast slab 14. Although not essential, most preferably the support socket 92 is provided as part of a modular insert which is removable, allowing its replacement and substitution with any change in the outlet opening 35 and cast slab profile. Each side of the carriage 82 carries a suitable bearing assembly which are respectively slidably mounted to a respective side rails 84a,84b. In this manner, the shuttle carriage 82 is selectively movable over the support surface 56 between a proximal position where the carriage 82 is spaced adjacent to the proximal end 51, and a distal position, where the shuttle carriage 82 is slid towards the table distal end 52. The drive 86 includes an electric motor 96 and a wire cable 98 which is guided by suitable pulleys to selectively slide the shuttle carriage 82 along the side rails 84a,84b between the proximal end distal positions.

Figure 6 shows best the guide track assembly 100 used in guiding the repositioning of the table 50 between the infeed and discharge positions. The guide track assembly 100 includes upper and lower guide tracks 102,104. In the side view shown, the guide tracks 102,104 are provided in a generally Y-shaped orientation, with each of the tracks 102,104 preferably formed as a pair of parallel spaced guide rails, along which the wheels 64,66 of the respective support legs 60,62 move.

The lower guide track 104 is shown best in Figure 6 as extending along the floor 47 of the access shaft 46 at an angle of about 45° from an upper end 110 which is positioned in a location towards the plant floor 17, to a lowermost end 112 positioned where the bottom of the access shaft 46 opens into the pit 16. Although not essential, preferably the upper end 110 of the guide track 104 extends generally horizontally along a shaft detent 150 which extends a distance D_b below the plant floor 17 a distance approximately equal to the depth Di of support leg 60. Preferably, the lower end 112 of the track 104 is spaced above the pit bottom 42 which is selected so that when the support leg 60 moves thereto, the proximal end 51 of the table 50 locates a distance of between about 2 and .5 metres beneath the cut-off saw 34.

The upper guide track 102 is provided in an orientation which inclines upwardly at an angle greater than that of guide track 104, and most preferably is positioned between about 50 and 70° relative to horizontal. The guide track 102 may be formed with either a straight or bent configuration, and extends downwardly from an upper end 116 which is spaced adjacent to the plant floor 17 to a lowermost bottom end 118 spaced proximate to the pit bottom 42.

The vertical distance separating the upper ends 116,110 of the guide tracks 102,104 is most preferably selected generally equal to the horizontal distance separating the lower ends 118, 112 of the tracks 102, 104. The upper ends 116, 110 of the guide tracks 102,104 are further positioned having regard to the spacing between and relative lengths of the forward and rearward support legs 60,62, such that when the table 54 is moved to the discharge position, the support legs 60,62 position the table support surface 56 in a substantially horizontal orientation, immediately adjacent to and vertically aligned with the infeed end of the exit conveyor 26. The lower ends 118,112 of the guide tracks 102,104 are similarly positioned having regard to the relative spacing between and lengths of the support legs 60,62 so that when moved thereto, the table 50 assumes the feed position with the support surface 56 aligned with the casting axis Ay- Ay, so as to be substantially coplanar with a side surface of the cast slab 14.

Optionally, a pushing assembly 120 may be provided to maintain lateral contact between the cast slab 14 and the support surface 56 during casting operations, as the slab 14 moves relative to the table 50.

In use of the continuous casting plant 10, the furnace 30 is used to melt and feed molten metal into the tundish 31. The tundish 31 in turn supplies the molten metal into the mould 34 in a substantially continuous manner, to continuously cast the slab 14 vertically through the mould outlet opening 35. As the slab 14 emerges from the mould 32, it moves downwardly along the casting axis Ay-Ay at a preferred rate of between about 5 cm and 12 cm per minute.

Initially, the table 50 is moved to the infeed position shown in solid lines in Figure 1, with the shuttle carriage 82 fully raised relative thereto, and adjacent the proximal end 51. As the end of the slab 14 moves downwardly, it engages the support socket 92. The contact pressure between the slab 14 and the shuttle carriage 82 activates the sensor 88 to operate the shuttle drive 86. The electric motor 96 of the shuttle drive 86 is used to slide the shuttle carriage 82 downwardly relative to the support surface 56 at substantially the same speed as the casting rate of the slab 14 so as to maintain bearing contact therebetween. In this configuration, the support socket 92 engages and supports the lower end of the slab 14 as it moves in the vertical direction of axis Ay-Ay, minimizing the tendency of the slab to slip from the pinch rolls 33 under its own weight.

As the lower end of the cast slab 14 and shuttle carriage 82 approach the distal end 52 of the table, the sensor 90 is triggered to activate the cut-off saw 34. The cut-off saw 34 severs the cast length of metal slab 24 adjacent to the mould outlet opening 35 as a discrete cut slab length 24.

Immediately following the activation of the cut-off saw 34, the table drive 50 is activated to wind the cable 68 about the shaft of the winding motor 70 to raise the table 50 from the infeed position to the discharge position shown in solid lines in Figure 6. As the cable 68 is wound, the table 50 is raised vertically from the pit 16 via the access shaft 46 and guide track assembly 100. As the severed length of slab 24 is raised, the pushing assembly 120 preferably provides a lateral pressure thereon, to maintain contact between the slab length 24 and the support surface 54 of the table 50. As the table 50 is drawn from the pit 16, the movement of the wheeled support legs 60,62 along the respective guide tracks 102,104 results in the support surface 54 moving with the cut length 24 thereon from a vertically oriented position to a generally horizontal position.

Once the table 50 is moved fully to the discharge position, the cut length 24 is positioned in a horizontal orientation, aligned with the infeed end of outfeed conveyor 26. When so positioned, the shuttle drive 86 is again activated to return the shuttle carriage 82 to its initial position adjacent the proximal end 51 of the surface 54. As the shuttle carriage 82 is slid along the side rails 84a,84b, engagement between the support socket 92 and the end of the cut slab length 24, results in the slab length 24 sliding along the rollers, off of the table 50 and onto the outfeed conveyor 26 for subsequent processing in the turnover station 27.

Immediately following the discharge of the cut length of slab 24, table drive 58 is again activated to reverse the electric winding motor 70. As the motor 70 is reversed, the table 50 is returned under gravity via the unwinding cable 68 to the infeed position within the pit 16, with the support surface 54 realigned vertically with the casting axis

The applicant has appreciated that by providing the cut-off saw 34 a distance spaced approximately .5 to 2 metres above the proximal end 51 of the table 50 when in the infeed position, vertical casting of slabs 14 may be performed continuously, even while severed slab lengths 24 are being moved out of the casting pit 16.

Although the preferred embodiment illustrates the casting plant 10 as vertically casting a slab 14 into a downwardly extending pit 16, other casting plant configurations may also be used. By way of non-limiting example, the casting machine 18 could be mounted in a location spaced vertically above the plant floor 17, as for example on a support frame (not shown). While the preferred embodiment describes the casting plant 10 as used to cast non-ferrous copper metal slabs, the invention is not so limited. It is to be appreciated that the transport table assembly 20 may be used with a variety of casting applications, including non-metal casting operations, as well as casting operations for ferrous metal strips, billets and/or slabs of a variety of different thicknesses and/or widths.

Although the detailed description describes the casting plant 10 as including a turnover station 27, the invention is not so limited. It is to be appreciated that other work stations could also or alternately be included. These include, without restriction, rolling stations, grinding stations, washing stations and the like.

While the preferred embodiment describes the use of cables 98,68 to effect movement of the shuttle carriage 82 and table 50, it is to be appreciated that other drive mechanisms including, without restriction, direct drive or indexing motors could also be used without departing from the spirit and scope of the invention.

Although the detailed description describes and illustrates various preferred embodiments, the invention is not so limited. Many modifications and variations will now occur to persons skilled in the art. For a definition of the invention, reference may be had to the appended claims.

Claims

We claim:

1. A transport table assembly for use with a casting machine operable to vertically cast a metal slab, the assembly including,

2. The table assembly as claimed in claim 1 wherein the casting machine is a vertical casting machine including a mould having mould outlet for substantially continuously vertically casting said metal slab therefrom, and a cut-off assembly operable to sever said length of said slab from a remaining continuously cast portion in said feed position, the first end of the table being spaced proximate to the mould outlet, the shuttle carriage being movable initially from said first position towards said second position by engaging contact with the continuously cast portion of the metal slab, as the metal slab is cast from said mould outlet.

3. The table assembly as claimed in claim 2 wherein the metal slab comprises a non-ferrous slab having a thickness selected at between about 100 mm and 220 mm.

4. The table assembly as claimed in claim 2, wherein when the table is in the feed position, the shuttle drive is selectively operable to move the shuttle carriage from the first position to the second position at a rate of speed substantially corresponding to a casting rate of said metal slab to substantially maintain engaging contact between the shuttle carriage and the continuously cast portion.

5. The table assembly as claimed in claim 1 further wherein the casting machine includes a cut-off assembly operable to sever said length of said metal slab from a remaining portion, a horizontally extending exit conveyor for conveying severed length of slab for further processing,

in the discharge position, the support surface being positioned in a generally horizontal orientation adjacent the exit conveyor, and wherein the operation of the shuttle drive to effect movement of the shuttle conveyor from the second position towards the first position, slides the severed length of slab from the support surface and onto the exit conveyor.

6. The table assembly as claimed in claim 5 wherein said support surface includes a plurality of rollers for movably supporting said severed slab thereon.

7. The table assembly as claimed in claim 1 wherein said metal slab comprises a non-ferrous metal slab having a thickness greater than about 2 mm, and the casting machine comprises a pit-type casting machine operable to substantially continuously cast said metal slab downward along a vertical axis into a downwardly extending pit, an access shaft extending angularly from a casting plant floor downward into a side portion of the pit, and

the table being movably supported on the guide track by first and second support assemblies,

the guide track including a pair of rails, a first one of said rails extending substantially along a bottom of said access shaft from a lower first slide end spaced towards a bottom of said pit to an upper first rail end spaced towards said plant floor,

the second other one of said rails extending from a lower second slide end positioned vertically below the lower first rail end to an upper second rail end positioned vertically above the upper first rail end,

the first support arm assembly being coupled to said table towards said support surface first end, and being associated with and movable long said first rail,

the second support arm assembly being coupled to said table towards said support surface second end, and being associated with and movable along said second rail,

the first and second support arm assemblies having relative lengths selected whereby when the support arm assemblies are moved towards the lower ends of the associated first and second rails, the support arm assemblies orient said table in said feed position in said pit with said support surface generally aligned with said vertical axis.

8. The table assembly as claimed in claim 7 wherein the relative separation and vertical distance separating the upper ends of the first and second rails is selected generally equal to the relative separation and horizontal distance separating the lower ends such that movement of the first and second support arm assemblies towards the associated first and second rail upper ends, repositions said table with said support surface in a generally horizontal orientation.

9. The table assembly as claimed in claim 7 wherein said table drive comprises an electric motor and lifting winch, wherein the angularly inclined portion of said first rail is inclined at an angle of between about 35 and 55° relative to horizontal.

10. A transport table assembly for use with a vertical casting machine operable to substantially continuously cast a metal slab, the assembly including,

11. The transport table assembly as claimed in claim 10 wherein said metal slab comprises a non-ferrous metal slab having a thickness greater than about 2 mm, and the casting machine is a pit-type casting machine operable to cast said metal slab downward along a vertical casting axis into a downwardly extending pit, an access shaft extending angularly downwardly from a floor surface into a side portion of the pit,

the guide track including a pair of rails,

a first one of said rails including an angularly inclined portion extending along said side opening from a lower first rail end spaced towards a bottom of said pit to an upper first rail end spaced towards said surrounding surface,

the second other one of said rails extending from a lower second rail end positioned vertically below the lower first rail end to an upper second rail end positioned vertically above the upper first rail end, the vertical spacing separating the upper ends of the first and second rails being selected substantially equal to the horizontal spacing separating the lower ends,

a first support arm assembly coupled to said table towards said support surface first end, and being associated with and movable long said first rail, a second support arm assembly coupled to said table towards said support surface second end, and being associated with and movable along said second rail,

the first and second support arm assemblies having relative lengths selected whereby when moved towards the lower rail ends of the associated first and second rails, the support arm assemblies orienting said table in said feed position in said pit with said support surface generally aligned with said vertical axis.

12. The transport table assembly as claimed in claim 11 wherein the casting machine includes a mould cavity having a mould outlet from which said slab is cast, and a pinch roll for drawing said slab from said mould outlet in said feed position, the first end of the table being spaced proximate to the mould outlet, and the shuttle carriage being movable initially from said first position towards said second position while maintaining engaging contact with at least a portion of the metal slab, to at least partially support said slab to minimize its slippage relative to said pinch roll.

13. The transport table assembly as claimed in claim 12 wherein the shuttle carriage is moved to the second position at substantially the same rate as a casting rate of the slab.

14. The transport table assembly as claimed in claim 10 wherein the casting machine includes a cut-off assembly operable to sever a length of said cast slab as a cut slab length when said shuttle carriage is moved towards the second position, a generally horizontal exit conveyor operable to convey each said cut slab length for further processing,

in the discharge position, the support surface being generally horizontally aligned with the exit conveyor, wherein the operation of the shuttle drive to effect movement of the shuttle conveyor from the second position towards the first position slides the severed cut slab length from the support surface and onto the exit conveyor.

15. In combination a transport table assembly and continuous casting machine, the continuous casting machine including a mould outlet for substantially continuously casting a metal slab vertically therethrough,

the table assembly including, a movable transport table having a support surface extending in a longitudinal direction from a first end to a second end,

a shuttle carriage configured for engaging contact with an end of said cast slab, the shuttle carriage being selectively movable in the longitudinal direction relative to the support surface from a first position spaced towards the first end to a second position spaced towards the second end as the slab is continuously cast, whereby the engagement between the end of the cast slab and the shuttle carriage at least partially supports the slab during casting to reduce slab slippage and/or damage,

16. The combination of claim 15 wherein the shuttle carriage is moved to the second position at substantially the same rate as the rate of casting the slab.

17. The combination of claim 16 further including a cut-off assembly, the cut-off assembly operable to interpose between said mould outlet and the table, and being activatable to sever a length of said slab as a cut slab length as said shuttle carriage is moved to said second position,

substantially immediately following the severing of said length of slab, the table drive being operable to move said table together with a said cut billet to said discharge position.

18. The combination of claim 17 further including an exit conveyor for conveying the cut slab length to further processing machines, when said table is moved to said discharge position, said first end of said support surface being moved substantially adjacent to an infeed end of said exit conveyor, in the discharge position the shuttle drive being operable to return said shuttle carriage to said first position and slide the cut slab length from the support surface onto the exit conveyor.

19. The combination of claim 18 wherein said metal slab comprises a non-ferrous metal slab having a thickness selected at between about 50 and 250 mm, the casting machine comprising a pit-type casting machine operable to cast said metal slab downward along a vertical casting axis into a downwardly extending pit, an access shaft extending downwardly from a floor surface into a side portion of the pit,

the guide track assembly including first and second rails,

said first rail comprising a pair of angularly inclined rail tracks extending along said access shaft from a lower rail end spaced towards a bottom of said pit to an upper rail end spaced towards said floor surface,

said second rail comprising a pair of inclined rail tracks extending from a lower end positioned vertically below the lower end of the first rail, to an upper rail end positioned vertically above the upper rail end of the first rail, wherein the relative vertical spacing separating the upper ends of the first and second rails being selected generally equal to the relative horizontal spacing separating the lower ends of the rails,

a first support arm assembly coupled to said table towards said support surface first end, and being associated with and movable long said first rail,

a second support arm assembly coupled to said table towards said support surface second end, and being associated with and movable along said second rail,

the first and second support arm assemblies having relative lengths selected whereby when the support arm assemblies are moved towards the lower ends of the associated first and second rail, the support arm assemblies orient said table in said feed position in said pit with said support surface generally aligned with said vertical casting axis.

20. The combination of claim 16 wherein said metal slab is selected from a copper slab and a copper alloy slab having a thickness selected at between about 50 mm and 250 mm, the shuttle carriage further includes a clamping assembly for releasably coupling said end of said slab thereto as the shuttle carriage moves from the first position towards the second position.

21. The combination of claim 20 wherein the clamping assembly is operable to couple said cut slab length thereto as said table moves from said feed position to said discharge position.