CA1052095A - Molten metal holding furnace - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A furnace vessel comprises a vertically oriented refractory lined cylindrical metal shell and a cover. The interior bottom of the vessel is dish shaped the vessel has external upwardly ending molten metal receiving and pouring spouts leading to the upper surface of the bottom.
The inlet to the receiving spout is higher than the outlet of the pouring spout whether the vessel is untilted or tilted to enable addition of molten metal to the vessel at all times. Means are provided for tilting the vessel on an axis that is on the same side of a transverse mid-plane through the vessel as are the pouring and receiving spouts. The tilt axis is directed through the outlet end of the pouring spout so the level of its tip is substantially unchanged when the vessel is tilted. The temperature of the metal in the vessel is maintained by heat radiated from an electrically resistive rod which extends across the interior of the vessel above the metal level. The ends of the heating rod are provided with electrical connectors and supports which are mounted on carriages. The carriages are mounted on track sections which tilt with the furnace and align with cooperating stationary track sections on which the carriages may be traversed for servicing the rod when the vessel is untilted. The axis of the rod is aimed such that an extrapolation thereof will not cross over the tilt axis within the width of the furnace so that the carriages and tracks are clear of the working area around the receiving and pouring spouts at all times.
The vessel is adapted for holding, reducing, alloying, degassing, vacuum treatment and introducing additives to molten metal during the interval between melting and utilization of the metal.

Description

iO5Z095 5. The present invention relates to a tiltable vessel or furnace for holding molten metal. Occasions for storing molten metal temporarily arise in steel making plants and foundries where large quantities of molten metal are available periodically from a refining furnace or cupola and the metal is used incrementally, such as for filling ladles or molds. The 10. holding furnace enables maintaining the molten metal at a desired temperature, and permits vacuum degassing of the metal, introduction of additives and treatment with process gases if desired. A desirable feature of a holding furnace is that it be adapted for receiving molten metal at the same time that it is discharging molten metal so as to maintain production 15. continuity despite the fact that metal from the holding furnace is u~ed in small increments and is available and ready in comparatively larger increments. A feature of the holding furnace described herein is that its components are arranged so they will not interfere with the working area at the front of the furnace when it is untilted nor when it is tilted.
20. ln accordance with the invention, a hollow refractory lined metal holding vessel has a molten metal receiving spout in which there is a channel leading to the interior o$ the vessel below the normally expected level of the ¦ molt metal therein. The rlle t to the rece ivir g spout is sù ~Antially above 105'~095 the molten metal level and is arranged to remain above this level when the furnace is tilted on a substantially horizontal axis. The vessel also has a pouring spout which has a channel whose inlet end is below the molten metal level when the vessel is either untilted or tilted and whose exit end 5. or pouring nose is below the inlet end of the pouring spout channel when the furnace is tilted. Means are provided for tilting the furnace vessel on a horizontal axis which is on the front side or same side of a transverse mid-plane of the vessel as are the receiving and pouring spouts such that the spouts do not rise or descend appreciably when the furnace is tilted 10. during regular molten metal receiving and pouring operations. An electrically resistive heating rod extends transversely interiorly of the vessel. The axis of the rod is so directed that it does not cross over the tilting axis of the vessel within the width of the vessel so that components affiliated with the rod externally of the vessel will not cause interference in 15. the working area in front of the vessel when the vessel is either untilted, or in normal operating position, nor when it i9 tilted.

An illustrative embodiment of the holding furnace will now be described in greater detail in reference to the drawings in which:
FIGURE 1 is a plan view of the holding furnace associated with a

2 0. cupola;
FMURE 2 is a front elevation view of the arrangement in FIGURE
l; and . ~ .

105'~095 FMURE 3 is a partial side elevational view of the vessel with portions broken away to show the configuration of the vessel along a plane which is normal to a vertical plane taken transversely through the vessel shown in the preceding figures.

5. FIGURE 1 shows a plan view of the holding furnace which is generally designated by the reference number 10. It comprises a normally vertically oriented cylindrical metal shell 11 which i9 lined with a suitable refractory material 12. As can be seen in FIGURES 2 and 3, the interior refractory lined bo~ttom 13 of the vessel is generally upwardly concave or dish shaped.
10. The vessel is provided with an arched roof comprised of blocks of refractory material 14 which are constrained against outward expansion by an annular frame 15. The roof is a unitary structure which sets on the top surface of the refractory walls 12 and is removable therefrom. As is evident in FIGURES 2 and 3, roof frame 15 has several eyes such as 16 15. and 17 welded to it for facilitating lifting the roof from the vessel body.
Removal of the roof may be accomplished with a hoist 18 which is movable on a monorail 19 between positions over the vessel and to tne side of the vessel as is evident in FIGURE 3. A spreader or equalizer assembly is used for coupling the hoist hook 21 to the roof so the roof may be lifted 20. in a level fashion. Equalizer 20 is T-shaped as viewed from the top and generally comprises a traversely disposed front beam 22 and a rearwardly extending beam 23 which may be joined perpendicularly to each other by welding or any suitable means.

ll p ~

105'~095 The rear of the furnace i9 provided with a door 26, as can be seen in FIGURES 2 and 3, which is primarily for removal of slag from the molten contents of the vessel. Door 26 comprises a metal casing 27 with a refractory lining 28. The door is on a hinge 29 which allows it to be swung 5. open for slag removal through an opening 30 in the refractory wall 12 of the vessel.
The vessel may also be provided with suitable conduits for intro-ducing solid materials and process gases to its interior or for evacuating the interior. This is suggested by the broken away conduit 31 which pro-10. trudes from the furnace roof as shown in FIGURES 1 and 2. It will be understood that the conduit is detachable connected to a conduit, not shown, leading to a source of solid materials, gases or vacuum. The detachable connector allows to be removed or replaced conveniently with hoist 18.
Conduits, not shown, providing alternative means for evacuating or 15. eupplying materials to the vessel may also be mounted on the vessel body to communicate with the interior of the vessel below the roof and above the ~ ~-expected level of molten metal in the vessel.
The bottom of the vessel may be equipped with a porous plug 34 leading to a gas supply conduit 35 which is connected to the vessel by means 20. of a nanged nipple assembly 36. The desired process gas under pressure isfed from a suitable source, not shown, to conduit 35 for the gas to diffuse through porous plug 34 and into the molten contents of the vessel from beneath the surface thereof. A typical use of the porous plug is for carrying out .

lOSZ095 the argon-oxygen stainless steel refining process.
The vessel is equipped with a generally radially and upwardly extending molten metal receiving spout 40 and a generally radially and upwardly extending pouring spout 41. Receiving spout 40 comprises an 5. upwardly angulated pipe 42 which is welded or otherwise jo~ned with metal vessel shell 11. An elbow 43 is connected by means of a flange 44 to pipe 42. The elbow and pipe are lined with refractory material which has a duct or channel 45 extending from an inlet opening 46 to an exit opening 47 next to the concave bottom 13 of the vessel. The bottom of channel 45 10. at channel exit 47 is substantially tangential or confluent to the concave bottom surface 13. Thus, when there is a signiflcant quantity of molten metal in the vessel, exit 47 and channel 45 are blocked by molten metal Qo that atmospheric air cannot enter the vessel through the receiving spout nor can process gas, if any is present, escape except if gas pressure would 15. be too high. The highest expected level of molten metal in the furnace is indicated by the dashed line 48 in FIGURE 3. --Pouring spout 41 comprises an upwardly angulated refractory lined pipe 49 joined with vessel shell 11. Pouring spout 41 terminates in a ;
pouring tip or nose 50 comprising a semi-cylindrical metal shel1 51 and a 20. refractory lining 52 which defines a channel 53. As can be seen in FIGURE 1, channel 53 is continuous with a channel 54 extending through refractory lined pipe 49. The entrance to channel 54 is marked 55 and, as can be seen particularly well in FIGURE 3~ the entrance is substantially confluent with 105'~095 the concave surface of refractory vessel bottom 13. Thus, when there is adequate molten metal in the vessel, the pouring spout will be blocked by the molten metal to prevent atmospheric air from entering the vessel and pre~surized processed gas, if any, from discharing out of the vessel as 5. was the case with the receiving spout. Note that the inlet opening 46 of the receiving spout is located above the tip 50 of the pouring spout ~o that when the vessel is tilted to pour metal there will not be an accidental discharge from the receiving spout.
The vessel may be mounted over a pit 55 in which there is a concrete lO. pier 56. A pair of pedestals 57 and 58 are anchored on the top of pier 56.
These pedestals are to support the vessel in a fashion that permits tilting it. ~ ~ -Pedestals 57 and 58 are similar so only one, 57, will be described. Its upper portion 59 is formed as a clevis for receiving an arm 60 therebetween.
Arm 60 is rigidly fastened to vessel shell 11. The arm and clevis are 15. connected with a pivot shaft 61. Pedestal 58 has a similar shaft 62 which is coaxial with shaft 61. Thus, as can be seen particularly well in FIGURE 1, the tilting axis of the vessel is on the front of the vessel or on the same side of a transverse vertical mid-plane of the vessel as are receiving and pouring spouts 40 and 41. It is desirable for an extrapolation of the tilting 20. axis to intersect the vertical axis of receiving spout inlet 46 and in or near -the tip channel 53 of the pouring spout so at least the latter r2mains at substantially the same level when the vessel is tilted with it~ front or nose end downwardly. This avoids otherwise likely collision between the pouring , ':' ` ' : ' '., -7- ~ ~

.. . .
:: . . . . --~OSZ095 spout nose and any object set below the nose for receiving molten metal poured from the vessel. For example, a ladle 63 may be suspended from a hoist 64 under the nose or exit tip of pouring ~pout 41. Since the nose of the pouring spout remains at substantially the same level when the vessel is 5. tilted with its rear or slag door end up, any container such as ladle 63 needs only to be located slightly below the pouring spout nose and no collision or interference between these objects will occur.
As can be seen best in FIGURE 3, the vessel may be rotated or tilted counterclockwise, that is, with its rear end up and with its nose 10. end remaining at a substantially constant level as suggested by the phantom line positions of the vessel marked 10'. The maximum angle of tilt for pouring in the illustrated design is about 30 from vertical. The vessel may also be tilted clockwise as viewed in FIGURE 3 to the position in which it is shown in phantom line mark 10" such that the slag door 27 is brought below 15. its normal operating level. Reverse nose tilting, as tilting with the rear end of the furnace going down is called, is used primarily when it is desired to remove slagfrom the molten metal surface 48 to slag door 27. Slag may be 8craped into a slag pot 65 which may be set on the floor 66 with a crane.
The mechanism for accomplishing both nose tilting and reverse nose 20. tilting comprises a pair of two-way fluid operated rams comprising cylinders 70 and 71. Parts associated with cylinders 70 and 71 are similar, so only cylinder 70 and its associated parts will be described in reference to FIGURES 2 and 3. As can be seen in FIGURE 3, the upper end of cylinder 70 terminates in a clevis 72 which is connected with a pivot pin 73 to a iO5;2095 bracket 74 which is fastened to vessel shell 11 on the far side as viewed in this figure. The cylinder contains a piston which has connected rod 74 extending therefrom and pivotally connected with a pin 75 to a ~tationary bracket 76 mounted on the floor of pit 55. Extending laterally from cylinder 5. 70 are a pair of cross pins 77 which normally rest on a pair of laterally spaced apart support levers 78 and 79. It will be evident that two-way cylinder 70 may be pressurized internally on one side of its interior piston to extend rod 74 relative to the cylinder and drive the vessel counterclockwise about its horizontal pivot to the upper phantom line position of the vessel 10. indicated in FMURE 3. Note in this figure that the nose or pouring spout 41 tip remains at substantially a constant level even though the rear end of the vessel rises a considerable distance. ~ -The vessel may also be tilted clockwise as viewed in FIGURE 3 through a relatively small angle such as about 10 in this example for 15. carrying on the deslagging operation mentioned above. Under these circumstances, support stop 78 is driven counterclockwise about its pivot 75 by means of a fluid operated cylinder 82 which is pivotally connected to `
bracket 76 and an arm 81 of stop 78. When stop 78 is tilted counterclockwise, pins 77 extending from cylinder 70 no longer rest on the stop and the piston 20. rod extension 74 may contract relative to cylinder 70 in response to the cylinder being pressurized on the appropriate side of its internal piston.
Upon this event, the rear end of the vessel is pulled downwardly to its phantom line position indicated by 10" in FIGURE 3.

.

105;~095 l It is evident in FIGURE 3 that when the vessel is tilted counterclock-¦ wise as indicated by its phantom line position 10', all the molten contents ¦ may be removed from the concave bottom 13 of the vessel because of its ¦ confluence with inlet 53 leading to the pouring spout.
5. ¦ Molten contents of the vessel are held at a desired temperature ¦ with an electrically resistive heating rod 85 that is shown in hidden lines ¦ in FIGURE 1 and in section in FIGURE 3. The heating rod is located above the highest expected molten metal level 48 so that the rod may radiate heat to the contents of the vessel. Rod 85 is preferably a highly 10. resistive and refractory material such as graphite. As will be~ elaborated subsequently, the rod should be located so it and its affiliated parts are in a convenient position for servicing and so they stay as clear as possible from the working areas of the vessel on the front side where the receiving and pouring spouts 40 and 41 are located and the rear side around the 15. slag door.
Note that a horizontal plane at about the same level as the base of the arched or internally concave furnace roof 14 constitutes a chord of an arc in conjunction with the concavity. The heating rod 85 is at a level below the chord and relatively closer to the upper surface 48 of the molten 20. metal than to the arced roof surface. The arrangement tends to reduceroof heating since radiation from the rod to the roof is reflected or re-radiated toward the molten metal.

105;~095 Considering the right end of the heating rod as viewed in FIGURE 2, one may see that the rod 85 is in a casing 86 and in FIGURE 3 it is evident that the rod may be engaged by a graphite sleeve 87 which is held by the casing 86. The casing is connected by means of a gland 88 in a sealed 5. relationship with a thimble fastened to the vessel shell. Rod casing or holder 86 is clamped to a movable carriage 90 which has upper pairs of rollers or wheels 91 and 92 and lower rollers 93. The upper rollers rest on the top flange 94 of an I-beam section 95 which is fastened to the vessel shell. The lower roller 93 engages top flange 94 on its bottom 10. and prevents the carriage from separating from the I-beam 95. Endwise and in substantial abutting relation with I-beam portion 95 is a stationary I-beam 96 constituting a track extension. Beam 96 has a cross section ;~, similar to that of beam 95. Because of the separation between carriage supporting beam or track 95 and stationary track 96, the rod supporting 15. carriage can swing or tilt with the vessel while track portion 96 remains in place. ; -The other end of the heating rod 85 is similarly mounted to the vessel and need not be described in detail except to say that it has a casing -~or holder 96 mounted on a carriage 97 that is supported by means of rollers 20. or wheels on a beam or track portion 98 which is fastened to the vessel.
Beam 98 is also aligned with an adjoining stationary track or beam 99.
It will be noted that both stationary track sections 96 and 99 are remote from and out of the way of the active area of the vessel which includes the 105;~095 receiving spout 40 and pouring spout 41.
When heating rod 85 i8 consumed by voltalization or if it breaks, rod holder 86 can be retracted from gland 88 and rolled onto track 96 by means of carriage 90. Its counterpart carriage 97 may also be retracted 5. and rolled onto track section 99. A new rod may then be inserted in the holder and tne latter may be pushed back to tne position in which it appears in the drawings while the other holder is similarly reinserted to engage tne free end of the rod and establish electrical continuity. The electrical connectors to the holders are not shown for the sake of brevity, 10. but it will be understood that they are supplied from cables, not shown, leading to a d-c source which is also not shown. ~`
In FIGURE 1 it is particularly evident that rod 85 and its carriages and the track sections 9S and 96 on one side and 97 and 98 on the other side of the vessel are aligned. The rod axis and aligned elements like on 15. a transverse vertical plane through tne vessel, that is, on a plane perpendicular to the drawing in FIGURE 1. Tn this particular example, ~e rod axis is at a slight angle of rotation with respect to a transverse plane that parallels the tilting axis of the vessel, that is, the axis of pivot pins 61 and 62. It is contemplated that the rod may be disposed at other 20. angles relative to a mid transverse plane as viewed from the top of the vessel but not at a sufficiently great angle to result in one of the rod carriages or the short track section on which it is supported extending into the working area around tne furnace such as tne area around the pouring and receiving spouts at the front of the vessel or around the slag door in the rear. Moreover, with the stationary tracks 96 and 99 at the side of the vessel they are always remote from the working areas. In the illustration, the rod is angulated only enough to avoid its associated 5. stationary track 99 being interfered with by an adjacent molten metalsource such as cupola 101 which will be discussed below. In general, it may be said that the rod may be located so that its axis, when extrapolated, will cross over the horizontal tilting axis of the vessel a ~
substantial distance to the side of the vessel and at least not cross over - ~ -10. said horizontal axis anywhere within the overall width dimensions of the ~ -vessel.
A holding furnace, such as has been described above, may cooperate ~ -with various means for supplying molten metal to it. 1~ the drawings, the holding furnace 10 is arranged for cooperating with a cupola 101 in which lS. molten metal is prepared in traditional fashion. The cupola has a base ~
102 from which a horizontal duct 103 extends. The other end of the duct i8 ..
coupled with a continuous open refractory lined trough or launder 104. The launder has a cha~rnel 105 that terminates in a tip 106 which i8 located over inlet 46 of receiving spout 43. It will be evident that, owing to the 20. tilting axis of the vessel extending through the receiving spout, the tip 106 of the launder 104 will remain over and aligned with inlet 46 regardless of an;y expected angle to which the vessel i8 tilted. Thus, whenever a heat from the cupola 108 is ready for use, it may be transferred to the vessel 10 . . ~ -. . ,-: , ........................... .
.. ; : .'' ~ 105'~095 through receiving spout 40 even though the vessel is discharging molten metal to a ladle or other metal receiving device simultaneously. Thus, vessel 10 may continue to pour and fill molds or ladles passed under the pouring spout with substantially no interruption even tnough additional 5. molten metal is available from tne cupola only periodically.
It should also be noted that although the tip 106 of launder 104 is rather close to inlet 46 of receiving spout 43, the launder need not be elevated when the vessel is reverse tilted since its rear end merely goes downwardly at this time without its front end and the receiving 10. and pouring spouts rising substantially.
~upola 101 is shown to have a drain launder 107 for removing slag after a heat is completed.
In some installations the holding vessel 10 may be located adjacent a steel refining furnace, a metal mixer or an additional large holding 15. vessel which may be provided with a launder analogous to launder 104 for discharging molten metal periodically into receiving spout 40. It is also contemplated that several sources of molten metal may be located adjacent -holding vessel 10 whereupon each may have a launder such as 104 extending over inlet 46 to maintain a high pouring rate by vessel 10.
20. Although a preferred embodiment of tne invention has been described in detail, such description is to be considered illustrative rather than limiting, for the invention may be variously embodied and is to be limited only by interruption of the claims which follow.

Claims (27)

1. A holding furnace comprising:
an enclosed refractory lined vessel, molten metal receiving spout means mounted on said vessel and having a channel whose lower end is in communication with the interior of said vessel, pouring spout means mounted on said vessel and having a channel whose lower end is in communication with the interior of said vessel, said channels of said receiving and pouring spout means extending outwardly from said vessel each respectively having an opening at its outer end, means supporting said vessel for tilting on an axis, tilt means coupled to said furnace and operable to tilt said vessel selectively on said axis for discharging metal therefrom and for returning said furnace to an untilted position, said receiving spout means and pouring spout means being mounted on said vessel on the same side of a generally vertical transverse mid-plane through said vessel as said tilting axis, the outer end opening in said receiving spout being disposed above the outer end opening of said pouring spout and being above the expected level of molten metal in said furnace through the opening in said receiving spout when said furnace is tilted and metal is being discharged from said pouring spout, and elongate heat producing means disposed in said vessel above the expected level of molten metal for providing substantial heat to the upper region of said metal, said elongate means being directed in said vessel such that an extrapolation of its axis does not cross the tilting axis of said vessel at least within the width of said vessel.

2. The apparatus of claim 1 including:
means disposed on the outside of said vessel for supporting opposed ends, respectively, of said elongate heating means, track means mounted on said vessel adjacent each of said supporting means for moving with said vessel when it is tilted, carriage means mounted for selective movement on said track means, respectively, said supporting means being mounted on said carriage means, respectively, and stationary track means adjacent each of said vessel mounted track means and being substantially continuous therewith when said vessel is untilted and separable therefrom when said vessel is tilted.

3. The apparatus in claim 1 wherein said refractory lining includes a refractory bottom in said vessel which has a generally dish shaped surface, the said lower end of said pouring spout channel being at least in part at the level of said surface and generally confluent therewith.

4. The apparatus in claim 1 wherein said vessel tilting axis is directed along a line that extends through said outer ends of said receiving and pouring spout means to thereby maintain said outer ends at substantially the same level when said vessel is tilted as when said vessel is untilted.

5. The apparatus in claim 1 wherein said vessel has an opening above the expected level of molten metal in said vessel when it is untilted, said opening being rearwardly of said mid-plane on a side opposite thereof from said tilting axis, door means mounted on said vessel for cooperating with said opening, said tilt means comprising extensible and contractible means interposed between a fixed point and said vessel, said means when extended causing said vessel to rotate about said axis in a direction to elevate the rear of said vessel and when contracted causing said vessel to rotate reversely to lower the rear of said vessel.

6. The apparatus in claim 5 wherein:
said extensible and contractible means comprise cooperating cylinder means and piston means movable selectively, in opposite directions therein under the influence of fluid pressure, means for pivotally connecting said cylinder means and said piston means to one and another, respectively, of a fixed point and said vessel, movable stop means, means on said cylinder means for engaging said stop means to thereby support said vessel in normal operating position, and means for selectively moving said stop means in an out of engagement with said engaging means whereby, when said means are disengaged, contraction of said means will tilt said vessel reversely.

7. The apparatus in claim 6 wherein said cylinder means is pivotally connected to said vessel at a point intermediate said mid-plane and said door means.

8. The apparatus in claim 1 including:
porous plug means extending through said vessel at a level below the molten metal when said vessel is in its untilted and normal operating position, and conduit means coupled with said plug means for delivering gas thereto and enabling said gas to diffuse through said plug means to the interior of said vessel.

9. The apparatus in claim 1 including conduit means leading to the interior of said vessel, said conduit means being adapted for connecting to a vacuum source.

10. The furnace set forth in claim 1 including:
cover means for said vessel having a lining comprised of refractory material, said refractory lining having an arcuate surface presented toward the chord thereof and toward the metal containment space interiorly of said vessel, said heat producing means extending transversely across the interior of said furnace substantially in a plane between said chord and said expected metal level.

11. The furnace set forth in claim 10 wherein said heat producing means comprises graphite rod means for producing heat by conduction of electric current, said rod means extending transversely of the interior of said vessel.

12. The apparatus in claim 1 including:
means for producing molten metal adjacent said vessel, launder means having opposite ends, one of which is in communication with said molten metal producing means and the other of which is disposed above said opening at said outer end of said receiving spout means for enabling molten metal to pour from said launder means into said opening when said vessel is untilted or tilted.

13. The apparatus in claim 12 wherein said means for producing molten metal is a cupola.

14. A holding furnace comprising:
a metal shell having bottom lining means and wall lining means comprised of refractory material defining a vessel having a space for containing molten metal, molten metal receiving spout means mounted on the front of said vessel and extending generally upwardly and having a channel whose lower end has an outlet is in communication with the interior of said vessel generally below the expected level of molten metal in said vessel and whose upper end has an inlet generally above said level, pouring spout means mounted on said front of said vessel and extending generally upwardly and having a channel whose lower inlet end is in communication with the interior of said vessel generally below the expected level of molten metal in said vessel and whose upper outlet end is generally above said level but below said receiving spout inlet, means for supporting said vessel for tilting about a substantially horizontal axis generally on the same side of the center of said vessel as the front on which said receiving and pouring spouts are mounted, said shell and wall lining means having spaced apart openings for receiving resistive heating rod means whose axis extends through said interior space of said vessel above said expected metal level, said rod axis being directed such that an extension thereof will not cross said tilting axis within the width of said vessel, first and second engaging means for engaging opposite end portions of said heating rod means, said engaging means cooperating with said openings, respectively, first and second movable means for supporting said respective engaging means from exteriorly of said furnace, first and second track means exteriorly of said furnace shell for supporting said movable means, respectively, for movement toward and away from said furnace, at least one of said track means being comprised of a first section carried by said furnace and a second relatively stationary section with a joint between said sections for permitting said movable means to be moved onto said stationary track section when said vessel is untilted to thereby enable retraction of said rod means from said vessel and for permitting said first section to be carried by said vessel during tilting, and means for tilting said vessel selectively in forward and reverse directions about said tilting axis.

15. The apparatus in claim 14 wherein said rod means and said track means are in substantial alignment and are displaced toward the rear of said vessel relative to the front thereof and to said spouts to enable locating said stationary track means remote from said spouts.

16. The apparatus in claim 14 wherein said rod means is in substantial parallelism with said tilt axis of said vessel.

17. The apparatus in claim 14 wherein said tilt axis is directed such that it projects generally through said outlet end of said pouring spout whereby said outlet end will maintain a substantially constant level when said vessel is untilted or tilted.

18. The apparatus in claim 14 wherein said tilt axis is directed such that it projects through said inlet end of said receiving spout and said outlet end of said pouring spout whereby said spout ends will maintain a substantially constant level when said vessel is untilted or tilted.

19. The apparatus set forth in claim 14 wherein said first track section of at least said one track means is substantially shorter than said second track section.

20. The apparatus in claim 14 including:
means for producing molten metal adjacent said vessel, launder means having opposite ends. one of which is in communication with said metal producing means and the other of which is disposed above said receiving spout inlet for enabling molten metal to pour from said launder means into said inlet when said vessel is untilted or tilted.

21. The apparatus in claim 20 wherein said means for producing molten metal is a cupola.

22. The apparatus in claim 14 wherein said refractory material bottom of said vessel has a surface generally concave toward the interior of said vessel and said inlet of said pouring spout channel is at least in part at the level of said surface and confluent therewith.

23. The apparatus in claim 20 wherein said rod means and track means are disposed along a line that passes said molten metal producing means and said launder means.

24. The apparatus in claim 14 wherein:
said wall lining means and said shell have an opening above the expected level of molten metal in said vessel when it is in normal operating position, said opening being rearwardly of said vessel on the opposite side of said rod means from said front side on which said receiving and pouring spout means are mounted, said means for tilting said vessel comprising selectively extensible and contractible means pivotally connected at one end to said vessel rearwardly from said rod means and pivotally connected at its other end to a fixed point, said tilting means when extended rotating said vessel about said tilt axis to raise the rear of said vessel and when contracted rotating said vessel about said axis to lower said rear end of said vessel.

25. The furnace in claim 14 including:
cover means for said vessel having a lining comprised of refractory material, said refractory lining having an arcuate surface presented toward the chord thereof and toward the metal containment space interiorly of said vessel, said heating rod means extending across said vessel interior in a plane between said chord and said expected metal level.

26. The apparatus in claim 14 wherein:
said tilting means comprises cylinder means and piston means therein, said piston means and cylinder means being relatively extensible and contractible in response to fluid pressure in said cylinder means, one of said cylinder means and said piston means being connected to said vessel more remotely from said tilt axis than is said rod means and stationary means to which said other end of said piston means is connected, stop means mounted for moving on said stationary means between first and second positions, means on said cylinder means for engaging said stop means when it is in said first position to thereby support said vessel in untilted position and permit said vessel to be turned in one direction about its tilt axis in response to extension of said tilting means, and means for moving said stop means to a second position for disengaging said means on said cylinder means to enable said vessel to be tilted in an opposite direction in response to contraction of said tilt means.

27. The apparatus in claim 14 wherein said heating rod means comprises graphite.