US3540706A

US3540706A - Heating furnace with skid rails

Info

Publication number: US3540706A
Application number: US800912A
Authority: US
Inventors: Charles Robert Wilt Jr
Original assignee: Salem Brosius Inc
Current assignee: Salem Brosius Inc
Priority date: 1969-02-19
Filing date: 1969-02-19
Publication date: 1970-11-17
Anticipated expiration: 1987-11-17
Also published as: DE1935656B2; DE1935656A1; FR2031507A1; GB1218305A; ES368867A1

Description

"United States Patent Charles Robert Wilt, Jr. Upper St. Clair, Pennsylvania 800,912

Feb. 19, 1969 Nov. 17, 1970 Salem-Broslus, Inc.

a corporation of Pennsylvania HEATING FURNACE WITH SKID RAILS 13 Claims, 8 Drawing Figs.

US. Cl

lnventor Appl. No. Filed Patented Assignee FieldofSem-ch .11. 263/6, 6A,

[56] References Cited UNITED STATES PATENTS 1,922,888 8/1933 Engelbert: 263/6 2,076,739 4/1937 Menough 263/6X 2,620,174 12/1952 Passafaro 263/6 Primary Examiner-John J. Camby Attorney-Buell, Blenko & Ziesenheim ABSTRACT: A furnace for heating metal objects such as slabs, blooms, beam blanks, or the like. The metal objects are pushed through the furnace on water-cooied skids. Means are provided in the furnace for transferring the metal objects from the water-cooled skids onto members which support the metal objects when they are at rest during the final heat cycle.

Patented Nov. 17, 1970 Sheet m2. of 5.

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his ATTORNEYS Patented Nov. 17, 1970 Sheet .1 w of 5 III F l I CHARLES R. WILTJr.

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Sheet .'5 of 5 INVENTOR.

CHARLES R. WELT Jr.

iz Maw his ATTORNEYS HEATING FURNACE WITI-I SKID RAILSv This invention relates to a heating furnace, and particularly I to such a furnace having improvements in the means for supporting objects during the final heating thereof.

One manner of heating metal slabs, blooms, beam blanks, and the like, is continuously heating them in familiar elongated furnaces. The work pieces are pushed into the furnace with conventional pushers and are supported in the furnace on water-cooled skids in preheating and heating zones. The work pieces are removed from the discharge end of the furnace by an extractor or are removed by passing them through a conventional dropout. A new piece is pushed in at the charge end of the furnace and all of the pieces in the furnace advance along its length with one piece being discharged from the furnacc. In the conventional furnace the work pieces are in contact with the skids until the pieces are urged into the soaking zone located at the discharge end of the furnace. Skid marks are formed on the undersurface of the work pieces in contact with the skids due to the continuous removal of heat from the pieces by the water flowing through the skids. These skid marks are removed from the work pieces by applying heat to the pieces in the soaking zone while the pieces rest on a solid refractory hearth. The work pieces are soaked by applying heat to their top surfaces, which then soaks through the pieces to supply the heat necessary to eliminate the skid marks. This soaking requires considerable time. Also, since the work pieces are pushed across the solid refractory hearth, the hearth is subject to considerable refractory wear and as a result requires frequent time consuming maintenance.

I overcome the problems set forth above inherent in a solid refractory hearth in the soaking zone of a continuous heating furnace. by providing a furnace which has a heating zone including water-cooled skids over which the work pieces can be pushed and multiple support members disposed between the skids and means for moving the support members or the skids for transferring the work pieces from the skids to the support members, whereby the skid marks are erased while the work pieces are on the support members. By supporting the work pieces on the support members heat can be supplied to both the top and bottom of the work pieces, and as a result, it will take less time for removal of skid marksformed on the work pieces as compared with soaking the pieces on a solid hearth.

Furthermore, the additional heat supplied to the work pieces will shorten the time to obtain a uniform temperature of the work piece required for further working of the piece. In addition, the multiple support members of the furnace of my invention are not subject to the wear problems associated with the solid hearth since the work pieces are not pushed along the support members but, rather, are pushed along the skids located in the final heating zone. In essence, what lam doing is eliminating the soaking zone of a continuous heating furnace and am providing a final heating zone, so to speak. Thus, the furnace of my invention also results in a furnace having a greater capacity together with better uniformity of temperature of the work pieces heated therein, relative to a conventional heating furnace ofthe same length. In addition, as 'compared with the same conventional furnace, I can shorten the length of my furnace and maintain equal capacity while providing better uniformity of temperature ofthe work pieces.

The principles of my present invention are also applicable to batch type heating furnaces. There are batch type furnaces which have either a solid refractory hearth or piers upon which the work pieces rest while being heated. I can provide a batch type furnace which will have the means for transferring work pieces from one object support means to another in accordance with the essence of the present invention. Thus, as compared to the conventional solid hearth or pier type batch furnaces, my furnace will result in work pieces reaching better uniformity of temperature in much shorter time, as well as eliminating other well-known refractory hearth and pier problems.

More specifically, I provide a furnace having the advantages just enumerated, as well as others, comprising: an elongated generally horizontally oriented hollow housing defining a furnace chamber; burner means disposed in the housing for supplying hot products of combustion into the furnace chamber to apply heat to the objects to be heated; a plurality of transversely spaced object support means supported in thehousing and extending throughout the length thereof for supporting objects during heating; the object support means having first members,.and second members disposed between the first members. with the members being movable upwardly and downwardly with respect to eachother; and movable frame means operatively arranged with the object support means for selectively tilting the members with respect to each other to transfer objects between the members.

Other details and advantages of the invention will become apparent as the following description of certain present preferred embodiments thereofproceed.

In the accompanying drawings I have shown certain present preferred embodiments ofthe invention in which: FIG. 1 is a vertical longitudinal sectional view through part ofa continuous heating furnace embodying the present inventiori, and showing the final heating zone of the furnace with the work piece support members in one position;

FIG. 2 is a view similar to that of'FIG. 1 showing the work piece support members in a second position;

FIG. 3 is a fragmentary vertical transverse sectional view taken along the line 3-3 of FIG. 2;

- FIG. 4 is a schematic representation of the pattern of a trough forming part of seal means for the present invention;

FIG. 5 is a fragmentary vertical transverse sectional view similar to that of FIG. 3 showing another arrangement of the work piece support members in the final heating zone of a continuous furnace of the present invention;

FIG. 6 is a vertical longitudinal sectional view through part of a continuous heating furnace embodying another form of the present invention, and showing the final heating zone of the furnace with the work piece support members in one position;

FIG.'7 is a similar view to that of FIG. 6 showing the work piece support members in a second position; and

FIG. 8 is a fragmentary vertical transverse sectional view taken along the line 8-8 of FIG. 6.

Referring now to the drawings wherein like reference numerals are used to designate like parts throughout the various views, 10 is a heating furnace through which work pieces such as slabs I1, for example, pass more or less continuously to be heated. The basic structure ofthe furnace 10 includes an elongated housing 14 defining a furnace chamber having a preheating zone, not shown, a heating zone 16, part of which is shown, and a final heating zone 18 disposed inwardly of the discharge end 20 of the furnace. Burners 22 are suitably arranged in the walls of the housing 14 for introducing into the furnace chamber hot products of combustion to apply heat to the slabs 11 passing therethrough. The slabs 11 are passed through the furnace chamber by being pushed one against the other in any well-knownmanner, moving from left to right as viewed in FIGS. 1 and 2 The slabs 11 are supported in the preheating and both heating zones on longitudinally extending, transversely spaced conventional water-cooled skids 24 suitably supported on platform 31. In general, except for the slab supporting means 30 in the final heating zone 18, the furnace 10 may be more or less conventional and since such furnaces and their operation are well known to those skilled in the art, I shall not describe in any detail any portions of the furnace except the structure of the support means 30.

Support means 30, asshown in FIGS. 1,2, and 3, includes a series of elongated, transversely spaced platforms 32 which are part of the overall platform 31, which platforms 32 are suitably supported on the floor of the foundation for the furnace 10. A pair ofdownstream sections 34 of the water-cooled skids 24 are supported by each of the platforms 32 by U- shaped, transversely oriented, pipes 36 longitudinally spaced on platform 32. Each of the skids 24, including skid sections 34, is provided over its entire longitudinal length with a conventional wear bar 35.

The object support means in the final heating zone 18 is movable upwardly and downwardly with respect to the skid sections 34. The object support means include elongated pedestal members 40 disposed in the spaces between the platforms 32v The details of one pedestal member 40 will be described with the understanding that the description pertains to each of the pedestal-members shown in the drawings. Each pedestal member 40 includes an upright tubular structure 42 formed in a fencelike pattern having a longitudinally extending upper section 43 and a plurality of vertical legs 44 joined to the upper section 43.-Upper section 43 is formed with two vertical levels, a first level 43a disposed adjacent the heating zone 16 and a second level 43!; below the first level and forming the remainder of the upper section. Circulating cooling water is passed through the tubular structure 42 and enters and leaves the vertical legs 44 by any suitable piping arrangement well known in the art. An elongated refractory cap 46 extends over the top surface of the second level 43b of upper section 43 of tubular structure 42. The refractory cap 46 is held fixed with respect to tubular structure 42 by bracket 47 suitably secured to the upper section 43. A short wear bar 48 is suitably fixed to the top horizontal surface of the first level 43a of upper section 43.

Each pedestal member 40 is supported by an upright support structure 50 which includes a pair of short pieces of transversely spaced first I-beams 52 disposed adjacent the discharge end ofthe furnace in the excavation 53 below the final heating zone 18. One each of a pair of elongated second I-beams 54 is fixed to each of the first I-beams 52 and extend from the first I-beams-to a vertical plane passing through an intermediate region of the heating zone 16. Pairs of short sections of first channels 56 are disposed at longitudinal intervals between the second I'-beams 54 and third I-beams 58. As shown in FIGS. 1 and 2, four pairs of first channels 56 are disposed as described. The third I-beams 58 extend in excavation 53 from adjacent the region of discharge end 20 of the furnace to a vertical plane passing through the entry region of the final heating zone 18. A pair of elongated second channels 60, shown in FIG 3, is fixed to the third I-beams 58 and is coextensive therewith. An elongated refractory block 64 is suitably fixed to the upper surface of the second channels 60. Passageways 66, shown in FIG. 3, are formed through the refractory block 64 for snugly receiving the vertical legs 44 of tubular structure 42. Brackets 68 are suitably fixed between the inner surface of the second channels 60 and the vertical legs 44 for providing additional support for the tubular structure 42.

As clearly shown in FIGS. 1 and 2, the structural members above second I-beams 54 are inclined downwardly with respect to the I-beams 54. This inclination is provided by suitably varying the height offirst channels 56. In addition, the height of vertical legs 44 of tubular structure 42 are suitably sized so that both levels of upper section 43 are substantially horizontal when support means 30 is in the position shown in FIG. 1. The inclination of members of support means 30 is necessary for providing the relationships between the pedestal members 40 and skid sections 34 as shown in FIGs. 1 and 2. These relationships will be better understood as the present description continues.

The final heating zone 18 and the excavation 53 are sealed from each other by well-known seals. As shown schematically in FIG. 4, the seals include a series of suitably supported troughs 70 circumscribing the area adjacent outer sides and ends of each individual third I-beams 58 forming part of an individual upright support structure 50. As shown in FIG. 3,

elongated blades

72 and 73 are fixed to the outer side of each third I-beam 58 forming part of an individual support structure and are shaped and sized to extend into the channels in between the support structures 50 formed by the troughs 70. As shown in FIGS. land 4

blades

75 and 76 are fixed to the ends of the third I-beams 58 and are shaped and sized to extend into the opposite end channels formed by troughs 70. A suitable seal level of sealing medium, such as water, for example, is maintained in the troughs 70 to insure a proper seal between the excavation 53 and final heating zone 18.

All of the support structures 50 are coupled together by a pair of elongated transversely extending I-beams 80 suitablyfixed to all of the first I-beams 52 forming part of the support structures 50. The entire assembly of pedestal members 40 and support structures 50'is supported on the floor of excavation 53 by pairs of laterally spaced drive units 82 and guide units 84 oppositely longitudinally disposed to each other. Each drive unit 82 includes a hydraulic cylinder 86 connected with a source of hydraulic fluid, not shown. The cylinder 86 is pivotably supported between a clevis bracket 88 suitably fixed to a base 89 resting on the floor of excavation 53. The piston rod 90 of the hydraulic cylinder 86 is pivotably connected with a clevis bracket 92 which is suitably fixed with I-beams 80. Each guide unit 84 includes an elongated base member and a pair of longitudinally oppositely disposed identical rollers 93 supported for rotation by identical clevis brackets 94 suitably fixed to the top of base member 95. An arcuately formed guide rail 96 is suitably fixed to second l-beams 54 and is arranged to engage the rollers 93. The guide rails 96 are shaped so that when each of the hydraulic cylinders 86 is actuated from its retracted state shown in FIG. 1 to extend the piston rod 90 to the position shown in FIG. 2. the assembly of pedestal members 40 and vertical supports 50 will move in an arcuate path towards and upwardly of the discharge end 20 of furnace 10, as it goes from the position shown in FIG. 1 to the position shown in FIG. 2.

The skid sections 34 and pedestal members 40 are sized so that the horizontal plane including the upper surfaces of the refractory cap 46 is disposed below the horizontal plane including the wear bar 35 when slabs 11 are being pushed through the furnace chamber. During pushing operations the wear bar 48 on the first level 43a of the upper portion 43 of vertical support 42 will be generally parallel to and below the wear bars on skids 24 in the heating zone 18. When the assembly of pedestal members 40 and support structures 50 is moved from the position shown in FIG. 1 to the position shown in FIG. 2, the plane of the refractory caps 46 will be inclined to and above the horizontal plane of the wear bars 35 of skid sections 34. Thus, by actuating the assembly to the position of FIG. 2, the slabs 11 originally on the portions of the skid sections 34 immediately above'the refractory caps 46 will be raised off of the skid sections 34 and supported on the refractory caps 46 forming part of the pedestal members 40. Therefore, when the slabs 11 are at rest (i.e. not being pushed through the furnace), the slabs in final heating zone 18 are heated while being supported by the pedestal members 40. As indicated earlier in this specification, it will take considerably less time, compared to a solid hearth, for removing the skid marks formed on'the slabs by skids 24 and, also, less time for obtaining uniformity of temperature of the slabs before being discharged from furnace 10 to be worked in a subsequent process, such as rolling, for example.

FIG. 5 illustrates another embodiment of the support means 30 forming part of the present invention. In FIG; 5, all of the structure described earlier is the same except that the pedestal members 40' are fixed to the platforms 32 and the skids 24 include upstream sections disposed in the preheating and heating zones and downstream sections 24b disposed in the final this embodiment the horizontal plane including the refractory caps 46 of pedestal members 40' is disposed below the horizontal plane including the wear bars 35 of downstream skid sections 24b. During pushing of the slabs, the piston rod 90 of the cylinder 86 will be fully extended in order to maintain relationship of the planes of the pedestal members 40' and downstream skid sections 2412, just described. After the completion of the pushing operation ofthe slabs 11 in the furnace, the piston rod 90 of cylinder 86 is retracted and the plane of the downstream skid sections 24b will then be disposed toward and downwardly of the discharge end 20 of the furnace l0, and below the horizontal plane ofthe refractory caps 46' of the pedestal members 40'. Thus, when all the slabs in the furnace are at rest, those slabs in the final heating zone 18 will be heated while they are supported by pedestals 40'.

The advantages of the present invention, i.e., fast elimination of skid marks from the work pieces, fast-heating time for reaching uniform work piece temperature, elimination of refractory hearth wear, greater capacity, and others. were spelled out in the introductory portion of this specification. It should be now better appreciated how the furnace of the present invention provides these aforementioned advantages. In addition, it should be noted that the arcuate or rocking" movement given to the slabs in the final heating zone provides an additional advantage to this invention. Each slab being pushed through a heating furnace is in abutment with the slabs adjacent thereto. As a result, it has been found-in conventional furnaces that slabs will, on occasion weld to each other by the time they reach discharge. Welding'generally occurs in the soaking zone of the conventional furnace. In this invention, the rocking-' movement provided by the means described regarding FIGS. 1, 2, 3, and 5 will cause the slabs to separate at the entry of the final heating zone 18 and, therefore, virtually eliminating any welding ofslabs to each other,

FIGS. 6 and 7 illustrate yet another embodiment of this invention. The embodiment of FIGS. 6 and 7 is essentially the same as that illustrated in FIGS. 1, 2, and 3, except that pedestal members simply tilt upwardly and downwardly with respect to the skids in the final heating zone. The furnace 100 includes downstream skid sections 102, forming part of elongated water-cooled skids extending throughout the length of the furnace, suitably supported by platform 104. Elongated pedestal members 106 are disposed between the downstream skid section 102, each of which pedestal members include an upright tubular structure 108 formed in a fencelike pattern having a longitudinally extending upper section 110 and a plurality of vertical legs 1'12joined to the upper section 110. Circulating cooling water is passed through the tubular structure 108 and enters and leaves the structure through the vertical legs 112 by any suitable piping arrangement well known in the art. An elongated refractory cap 114 extends over the top surface of each upper section 110 and is suitably fixed thereto by bracket 116. Each pedestal member 106 is suitably fixed to an elongated beam 118 extending longitudinally with respect to the furnace. The beams 118 are fixed to one another by

beams

120 and 122 suitably secured to the respective upstream and downstream ends of the beams 118. The

beams

118, 120 and 122 are disposed below the final heating zone 124 in an excavation 126 suitably arranged below the furnace. The pedestal member 106 assembly, including the

beams

118, 120, and 122, is supported on the floor of excavation 126 by pairs -of laterally spaced drive means 130 and guide means 132, op-

positely longitudinally disposed to each other. Each drive unit includes a hydraulic cylinder 134 connected with a source of hydraulic fluid, not shown. The cylinder 134 is pivotably supported between a clevis bracket 136 suitably fixed to a base 138 resting on the floor ofexcavation 126. The piston rod 140 of the cylinder 134 is pivotably connected with a clevis bracket 142 which is suitably fixed to beam 122. A clevis plate .144 is suitably fixed to beam 120 and is pivotably connected with plate 146 suitably fixed to the top of base 148 resting on the floor ofexcavation 126.

The'skid sections 102 and pedestal members 106 are sized so that the horizontal plane including the upper surfaces of the refractory caps 114 is disposed below the horizontal plane including the wear bars onthe skids, including downstream skid sections 102. During pushing operations the slabs 150 will move through furnace 100 over the skids. When the slabs 150 come to rest, the cylinders 134 are actuated to extend the piston rods 140. The pedestal members 106 all tilt upwardly towards the discharge end of the furnace, as shown in FIG. 7. Thus, the slabs 150 in the final heating zone 124 which were originally on the upstream skid sections 102 will be raised off of the skid sections and supported on the refractory caps 114 forming part of pedestal members 106. The piston rods are retracted to return the pedestal members 106 to the position shown in FIG. 6.

It should be clear that the furnace of FIGS. 6-8 has essentially the same advantages as those set forth for the earlier embodiments. It should also be noted that the furnace of FIGS. 6- 8'can be adapted so that the skid sections in the final heating zone 124 are arranged to tilt relative to the pedestal members. Such an arrangement would be similar to the embodiment of the invention illustrated in FIG. 5. It should be further noted that the embodiment of this invention illustrated in FIGS. 6-8 could be simply adapted to a batch heating furnace; although it should also be understood that the other embodiments of this invention can, likewise, be adapted to a batch furnace. In batch furnaces, however, there would be no need to have water-cooled skids. The work pieces could be placed on piers, for example, and then raised onto pedestal members in any of the manners set forth above.

In the embodiments of this invention previously described, the movable object support members located in the final heating zone were provided with means to move them in a more or less upwardly and downwardly slanting relationship with respect to the stationary support members. I refer to this movement as being along a tiltable path; with the understanding, however, that this expression is not limited only to tilting as illustrated in FIGS 6, 7, and 8, but to any movement which results in one set of support members being inclined with respect to another set of support members to result in the transferring of objects between the support members to achieve the advantages set forth hereinabove.

While l have shown and described present preferred embodiments of the present invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied within the scope of the following claims.

Iclaim:

l. A furnace for heating objects, comprising:

an elongated gener'allyhorizontally oriented hollow housing defining a furnace chamber having first heating zones and a final heating zone inwardly adjacent the discharge end of the housing;

burners disposed in said housing for supplying hot products of combustion into the chamber to apply heat to the ob jects to be heated;

a plurality of elongated transversely spaced skid means supported in said'housing and extending longitudinally with respect thereto for supporting objects therein;

a plurality of elongated transversely spaced pedestal means disposed between said skid means in said final heating zone and having object supporting upper surfaces;

the plane extending transversely of said housing and including the upper surfaces of said pedestal means is below the plane extending transversely of said housing and including the upper surfaces of said skid means when objects to be heated are being pushed along the skid means through the furnace chamber; and

movable frame means for supporting all of one of said means and for selectively tilting such means upwardly and downwardly with respect to the discharge end of said housing from a first position where the said plane of said skid means is above said plane of said pedestal means to a second position where said plane of said skid means is inclined to and below said plane of said pedestal means,

whereby objects being pushed in said furnace chamber upwardly and downwardly with respect to the discharge end of i said housing from a first position where said plane of said pedestal means is below said plane of said skid means to a above and inclined upwardly towards said discharge end with respect to said plane of said skid means.

3. A furnace as set forth in claim 1 wherein said skid means include first skid members disposed in said first heating zones and second skid members disposed in said final heating zone and detached from said first skid members; said frame means supports said second skid members and isselectively tiltable upwardly and downwardly with respect to the discharge end of said housing from a first position where said plane of said pedestal means is below the plane extending transversely of said housing and including the upper surfaces of said second skid members to a second position where said plane of said second skid members is below and inclined downwardly towards said discharge end with respect to said plane of said pedestal means.

4. A furnace as set forth in claim 1 wherein saidframe means includes an elongated base means extending generally longitudinally of said housing; guide means operatively arranged atone end portion of said base means for guiding said base means along an arcuate upward and downward path; drive means operatively fixed with the other end portion of said base means for selectively moving said base means up-' wardly and downwardly along said path.

5. A furnace as set forth in claim 1 wherein said frame means includes an elongated base means extending generally longitudinally of said housing; guide means operatively arranged atone end portion of said base means and including at least one guide rail formed in an arcuate shape defining an upward and downward path for said base means and at least one roller in engagement with said guide rail; and extensible and retractable drive means fixed with the other end portion of said base means for selectively moving said base means upwardly and downwardly along said path.

6. A furnace as set forth in claim 1 including sealing means between said housing and said frame means for sealing the furnace chamber above said frame means from the area below said frame means.

7. A furnace as set forth in claim 1 wherein said frame means includes a plurality of elongated transversely spaced beams extending generally longitudinally of said housing; attachment means fixed between said beams for attaching the sequentially spaced beams to each other; an elongated upwardly extending post means fixed to each of said beams and disposed in the area of said final heating zone for supporting one each 'of said pedestal means in an upright position such that said plane of said pedestal means is below said plane of said skid means; at least one roller supported below said housing and disposed below one of said beams at one end portion thereof; a guide rail fixed to one of said beams and in engagement with said roller, and formed in an arcuate shape to provide said beams with a'path of movement towards and upwards of the discharge end of said housing and away and downwards of the discharge end of said housing, and extensible and retractable drive means fixed to one of said beams at the other end thereof for selectively moving said beams along said path.

8. A furnace as set forth in claim 3 wherein said frame means includes a plurality of elongated transversely spaced beams extending generally longitudinally of said housing; attachment means fixed between said beams for attaching the sequentially spaced beams to each other; support means on each ofsaid beams for supporting one each of said second skid members in an upright position; said pedestal means is fixed with respect to said housing; at least one roller supported below said housing and disposed below one of said beams at one end portion thereof; a guide rail fixed to one ofsaid beams and in engagement with said roller and formed in an arcuate shape to provide said beams with a tilting path of movement towards and upwards of the discharge end of said housing and away and downwards of the discharge end of said housing; and extensible and retractable drive means fixed to one of said beams at the other end thereof for selectively moving said beams along said path.

9. A furnace as set forth in claim 1 wherein said frame means includes an elongated base means extending generally longitudinally of said housing; guide means operatively arranged atone end portion of said base means and including at least one first plate member supported below said base means and a second plate member fixed to said base means and pivotably connected with said first plate member; and drive means operatively fixed with the other end portion of said base means for selectively tilting said base means upwardly and downwardly.

10. A furnace for heating objects, comprising:

anelongated generally horizontally oriented hollow housing defining a furnace chamber;

burners for supplying hot products of combustion into the furnace chamber to apply heat to the objects to be heated;

a plurality of elongated transversely spaced object support means supported in said housing for supporting objects during heating;

said object support means having first members for supporting objects, and second members disposed between said first members, with said members being tiltable upwardly and downwardly with respect to each other; and

movable frame means operatively arranged with said object support means for selectively tilting said members with respect to each other to transfer objects between said members.

11. A furnace as set forth in claim 10 wherein said frame means includes guide means for guiding said frame means in an upwardly and downwardly arcuate path with respect to one end ofsaid housing.

12. A furnace as set forth in claim 10- wherein said first members of said object support meansincludes a plurality of water-cooled skids; said skids having an upstream first section and a downstream second section; said second members are a plurality of pedestals disposed between said second section of said skids and having object bearing upper surfaces; said housing has a charge end and a discharge end; said frame means supports said pedestals and is selectively tiltable upwardly and downwardly with respect to the discharge end of said housing from a first position where the plane of the upper surfaces of said pedestals is below the plane of the second section of said skids to a second position where said plane of said pedestals is above and inclined upwardly towards said discharge end with respect to said plane of said second section of said skids 13. A furnace as set forth in claim 10 wherein said first members of said object support means includes a plurality of water-cooled upstream first skids; and a plurality of watercooled downstream second skids; said second members are a plurality of pedestals disposed between said second skids and having object bearing upper surfaces; said housing has a charge end and a discharge end; said frame means supports said second skids and is selectively tiltable upwardly and downwardly with respect to the discharge end of said housing from a first position where the plane of the upper surfaces of said pedestals is below the plane of the second skids to a second position where said plane of said second skids is below and inclined downwardly towards said discharge end with respect to said plane of said pedestals.