US2472954A

US2472954A - Adjustable roof mounting means for top charged electric furnaces

Info

Publication number: US2472954A
Application number: US535332A
Authority: US
Inventors: Moore William Enoch
Original assignee: Delaware Engineering Corp
Current assignee: Delaware Engineering Corp
Priority date: 1944-05-12
Filing date: 1944-05-12
Publication date: 1949-06-14
Anticipated expiration: 1966-06-14
Also published as: ES181339A1

Description

June 14, 1949. w, MOORE 2,472,954

ADJUSTABLE ROOF MOUNTING MEANS FOR TOP CHARGED ELECTRIC FURNACES Filed May 12, 1944 2 Sheets-Sheet '1 INVENTOR William E.Mo0re 7 June 14, 1949.

Filed May 12, 1944 W. E. MOO

ADJUSTABLE ROOF MOUNTING MEANS FOR TOP CHARGED ELEGTRIC FURNACES 2 ShetS-Sheet 2 INVENTOR m'zziamfiMoore Ada/i M/M/ Patented June 14, 1949 ADJUSTABLE ROOF MOUNTING MEANS FOR TOP CHARGED ELECTRIC- FURNACES William Enoch Moore, Pittsburgh, Pa, assignor to Delaware Engineering Corporation, a corporation of Delaware Application May 12, 1944, Serial No. 535,332

11 Claims. (Cl. 110-99) My invention relates to electric furnaces, particularly to electric furnaces for producing and refining metal, and more particularly to electric furnaces having a roof adapted to be lifted from the body of the furnace and swung. aside, to give access to the. furnace chamber from above for such purposes as charging the furnace and making bottom.

Electric furnaces of this type are known in the art. The electrodes of the furnace extend through the openings provided therefor in the furnace roof. The electrodes are vertically adjustable in their extent through the roof to the degree necessary to maintain proper position of the discharge ends of the electrodes with respect to the charge within the furnace. In furnaces of the type I have especially in mind, the electrodes are borne by supporting masts that rise from a support which in the parlance of the art is known as a spectacle, and the spectacle is supported either upon an independent foundation at the side of the furnace or immediately upon the metal shell of the furnace body itself. The furnace roof is supported by means of beams that extend from the spectacle. In case the furnace be a tilting furnace, the spectacle is adapted to tilt with the furnace body, and the electrode and roof supporting structure tilts in unison with the spectacle, as also do the electric cables that are looped from the electrode arms carried by the supporting masts, whence they extend to the usual stationary conductors and bus-bars that supply electric current from the transformer equipment of the furnace installation,

My invention consists in the provision of a roof support that provides for the adjustment of the furnace roof with respect to the beams that support it. More particularly, the invention consists of certain new and useful improvements in a roof support, to the end that universal adjustment of the supported roof is afforded, whereby the roof may be positioned with the electrode openings centered with respect to the electrodes, and with the rim of roof arranged to meet the top edge of the crucible-like furnace body in a snug engagement that is effective throughout the entire periphery of the furnace body.

' The invention will be imderstood that upon reference to the accompanying drawings, in which:

Figure 1 is a view in front elevation of an electric furnace of the sort in which the invention may be embodied. The roof of the furnace is shown to be borne by a support which serves in exemplary way to illustrate the invention;

Figure 2 is a fragmentary view, illustrating the roof and its supporting structure in plan from above;

Figure 3- is a fragmentary view showing, to larger scale, partly in elevation and partly in section, on the plane III-III of Figure 2., an important element of the exemplary roof supporting structure of the invention; andv Figure 4 is a fragmentary view of such structure, as seen in elevation on a vertical plane located, to the left of Figure 3 Referring to Figure 1 of the drawings the reference numeral i0 is applied toa furnace crucible or body having a removable roof ll. The furnace is illustrated as an arcv furnace haying electrodes 12 and electrode columns or masts l3, upon which ride the usual horizontal arms (notv shown) for supporting the electrodes and conveying current thereto while riding on the masts l3 carried by the spectacle casting. The spectacle casting is inthis case supported on the metal shell of the furnace body, and is arranged to be raised and lowered, and swung in a horizontal plane, by means of a hydraulic plunger 4.5 that is powerfully reciprocable and. rotatable a cylinder 43 rigidly secured to the: side. of the metal shell of the furnace body or crucible. The roof of the furnace, comprising a dome Ha of refractory blocks arched from a skew-back or roof-ring 1 lb, is borne by a. pair of horizontal beams. 9, 9 which in turn are borne by the spectacle casting. The general construction of the furnace is fully illustrated and described in United States Letters Patent No. 2,261,587, granted to me November 4, 1.941., and herein I. shall only briefly review the description to the extent necessary to indicate one of the. several types of furnaces in which the improvements of my invention may be enjoyed.

On each side of the metal shell of the crucible a metal bracket I5 is welded or otherwise secured. These two brackets project laterally beyond the crucible, one on each side of the pouring spout l6 and terminate in bearings IT, A metal support. It is provided for each bracket, and each support is bolted or otherwise firmly attached, to the concrete foundation illustrated, and is bifurcatedv at its. upper end to receive the bearing ll of the associate bracket IS. A pivot pin 20 provides articular union of each. bracket with its support IR.

A pit 2.! is arranged in the foundation beneath the furnace, and two hydraulic cylinders 22 (one cylinder lies behind, the other in the line of sight in. Figure 1) are pivotally secured at their lower ends to spaced, brackets 23 secured at the base of the pit in line with the centre of the furnace. As may be clearly understood upon reference to said Letters Patent No. 2,261,587, a pair of brackets 24 is secured to the convex bottom of the furnace shell adjacent the centre line of the furnace, preferably slightly behind the centre lifi', and the hydraulic pistons 25 of cylinders 22 have bifurcated ends that are pivotally secured to these brackets. as to be arranged adjacent the outer wall of the furnace, so that there will be no tendency on the part of the furnace to twist as it is moved about the pivots 20.

Two spaced depending feet or legs 26 (here again one leg lies out of sight) are secured to the bottom of the furnace shell at points opposite the tilting pivot 29, and these legs are adapted to support the furnace in either of two positions.

A concrete wall or pillar 21 terminates below the lower level of the furnace or the floor level and in line with the legs or feet 26. Supporting castings 28 are secured to the wall 21 below the feet 26, and each casting is provided on the side farthest from the furnace with a pivot pin 29 to which a pedestal 39 is pivotally secured. The pedestals 3D normally rest upon the castings 28 and extend vertically upwardly to contact the feet 26 and support the furnace in a level or horizontal position. A projection 3| is secured to the lower end of each pedestal and is curved downwardly to engage the Wall 21 when the pedestal is pivoted about pin 29 to support the pedestal in the broken line position indicated, out of the path of corresponding foot 26.

When the pedestals are in their broken line or non-operating position, the furnace may be tilted back past the horizontal position into slagging or back-tilt position indicated by broken lines 32. In this position the feet 26 rest upon the immovable pedestal supports 33 which may be an integral part of casting 28, and which are arranged forwardly of pedestals all. When the pedestals 39 are in operative position, their upper faces and the upper faces of supports 33 are disposed in the arcuate paths through which feet 26 move when the furnace is moved about its tilting pivot 20.

'It will be seen that when pistons 25 are forced outward in cylinders 22, furnace II] will be moved about pivots 20 to the pouring position indicated by broken lines 34. When pressure is released the furnace will return to the level position with the feet 26 resting on pedestals 30. When it is desired to move the furnace to its back-tilt or 'slagging position 32, the furnace is raised slightly so that pedestals 30 may be swung out of the way and the furnace may then be lowered into contact with supports 33 by releasing the pressure in cylinders 22. By locating the brackets 24 adjacent the centre line of the furnace, an even pivoting is obtained with no detrimental thrusts on pivot pins 20 and bearings I! and I9 and without the use of exceptionally long cylinders. While the furnace may be tilted by one cylinder centrally arranged, and supported by one foot and pedestal also centrally arranged, the use of pairs of these elements, spaced as shown in my said prior patent, produces a much smoother action without danger of twists and strains.

I Any suitable hydraulic system may be employed to operate the pistons 25, and it is needless to involve this specification with such details.

I In the operation of the furnace, it is necessary to remove the furnace roof to give access to the furnace chamber for charging, making bottom, or

The brackets 24 are so spaced other purpose. This operation of the roof may be conveniently accomplished by means of the

hydraulic ram

43, 45 arranged to raise the roof and swing it way from the furnace body. The ram may be supported by the furnace foundation and arranged to engage and disengage the roof, or it may be, as herein it is, mounted on the furnace shell It) to move therewith and thus dispense with the necessity of disengaging the ram from the roof in order to permit tilting of the furnace. The ram cylinder 43, as has been said, is rigidly secured to the furnace shell and is provided with a plunger 45. A cam slot 48 is formed in the wall of cylinder 43 adjacent the upper end thereof and a roller 49 is secured to the plunger and disposed in slot 48. Such a structural organization is fully disclosed in my said Letters Patent No. 2,261,587. When the plunger is forced upwardly, the roller 49 moves upwardly in a vertical portion of the cam slot 48 and the roof moves upward with vertical motion only. Then the roller reaches an inclined portion of the cam slot, at which time the roof will have cleared the top edge or rim of the furnace body, and the further upward movement of the plunger serves to rotate the rising plunger and swing the upwardly moving spectacle l4, beams 9, 9 and supported roof II from above the furnace body. The means for delivering liquid or fluid under pressure to effect such operation of the plunger are well known in the art, and need not be considered herein. Suflice it to say, when the roof is to be raised and swung, fluid is fed to the ram, and, alternatively, when the roof is to be returned to its normal position on the furnace body, the operating fluid is cut off and the cylinder opened to discharge, whereupon under the effect of the weight of the elevated structure the parts descend and swing into their original positions.

Turning now to a consideration of the roofsupporting structure of the invention, it will be realized that it is desirable not only that the furnace roof shall be firmly supported for the raising and swinging operation, but that it also shall be adjustable in its supported position, to insure that the roof may be properly positioned relatively to the electrodes that extend through it, and may be seated tighly or snugly upon the top edge or rim of the furnace body, in an engagement that is uniformly effective throughout the entire peripheral extent of the furnace. To this end the means for rigidly securing the roof to its powerfully actuated support are particularly effective to afford universal roof adjustment.

Such means comprise a plurality of hanger assemblies A, in this case four hanger assemblies, two associated with each of the two

cantilever beams

9, 9. It will be noted that each beam 9 is of longitudinally slotted construction, the slot being advantageously obtained by forming each beam of two

steel channels

50, 50 that are arranged back to back, but spaced apart to provide between them the desired slot. The two channels of each cantilever beam are rigidly united at their distal ends, and also at spaced points in their extent, by metal spacer elements 5| welded in place, and at their proximal ends the two channels are welded to heavy metal plates 52 that are securely bolted to the spectacle casting l4, as indicated at 53 in Figure 2. Each of the four hanger assemblies A includes a load-sustaining tension member that extends downwardly through the slot in the beam with which it is organized and engages the metal roof-ring ill), the roof-ring including a peripheral flange He. The roof-ring is preferably of the construction amt-e54 disclosed in my copending application, Serial No. 508,486, filed November 1, I943, now matured into U. S. Patent No. 2,414,545, dated January 21, 1947,

The load-sustaining member of each hanger assembly consists in a threaded stem or shank 54 that extends through

sleeve washers

55 and 56 arranged as shown in Figure 3. Above and below the

washers

55 and 56, respectively,

handleequipped nuts

51 and 58 are provided on the threaded shank 54, and by tightening these nuts against the sleeve washers, it is manifest that the threaded shank may be rigidly clamped to the slotted. beam structure through which it extends. Projecting downward from the beam, the shank is threaded in the upper arm of a o-clamp 59 that embraces the peripheral flange lie of the roof-ring, and by rotating the shank (the nut 58 being loosened) the end of the shank may be screwed against the roof-ring flange llc to lock the C-clamp thereto. The shank 54 is provided at its upper end with a handle 60 which is rigidly secured to the shank as by welding, and by means of this handle, the rotation of the shank may be readily efi'ected. ,Such is the structure of each of the several hanger assemblies that together suspend the roof structure from the

beams

9, 9, and rovide for the universal adjustment of the suspended roof, as follows: 7 By loosening the lower nuts 58 of the several hanger assemblies A, the clamped engagement of the hanger assemblies to the beams is released, and the roof is sustained by the bearing of the nuts (through washers 55) upon the top edges of the beams. Accordingly, the roof may be horizontally adjusted in the direction of the slots in the beams, it being understood that the sleeve washers 5'5 and 56 extend between the channels that form the beams with sufficient clearance to permit the sliding of the hanger assemblies lengthwise of the beams. By unscrewing the shanks 54 and removing their lower ends from engagement with the roof-ring, the roof may be rotated in the plane of its expanse, the flange lie of the ring sliding within the C-clamps. Thus, any desired angular adjustment of the roof in a horizontal plane may be efiected, and it will be manifest that, by effecting the rotation of the suspended roof in conjunction with the adjustment of the hanger assemblies longitudinally of the supporting beams, the roof may be shifted laterally to one side or the other of the beams. In brief, the roof may, within adequate limits, be adjusted in every direction in the plane of its extent. Additionally, by rotating the nuts 51 of the several hanger assemblies in one direction or the other, the threaded shanks may be raised or lowered, correspondingly adjusting the vertical position of the roof, and by the selective adjustment of the nuts 51 the roof may be tilted to bring it into exactly the proper plane for snug engagement with the top edge or rim of the furnace body. It will be understood, therefore, that the structure described provides a universal adjustment of the roof. When the roof has been properly adjusted, the threaded shanks are rotated to lock the G-clamps to the roof-ring, and the nuts 58 are tightened to lock the hanger assemblies to the supporting beams. The roof is firmly secured to supporting beams.

Whereas the furnace herein illustrated is of the tilting type, it will be understood that the roof-supporting structure of the invention may be used with a non-tilting or stationary furnace. Whereas the spectacle casting l4 and the hydraulic cylinder and plunger unit are herein shown to be secured to the metal shell of the crucible I0, it will be understood that such casting and hydraulic unit may be mounted upon an independent support at the side of the furnace. And whereas the roof-supporting

beams

9, 9 are illustrated to be cantilever beams supported by the spectacle casting I4, it will be understood that such beams may comprise the essential elements of the well-known gantry type of roof support, or the like.

Within the terms of the appended claims various modifications and variations may be employed without departing from the invention covered herein.

I claim as my invention:

1. A support for a furnace roof comprising a. horizontal beam, and means for securing the roof to the beam comprising a load-sustaining member adjustable vertically and longitudinally of the beam and provided with a device adjustable along the periphery of the roof for engaging the member to the roof, and means for looking the adjusted load-sustaining member to the beam.

2. A support for a furnace roof comprising a cantilever beam, and means for suspending the roof from the beam comprising a load-sustaining tension member adjustable vertically and horizontally of the beam and provided with means adjustable along the periphery of the roof for engaging said tension member to the roof, and means for locking the adjusted load-sustaining member to said beam and roof.

3. A support for a furnace roof comprising a horizontal beam, and means for securing the roof to the beam comprising a plurality of loadsustaining members severally adjustable vertically and longitudinally of the beam and provided with devices severally adjustable along the periphery of the roof for engaging the members to the roof, and means for severally locking the adjusted load-sustaining members to the beam.

4. A support for a furnace roof comprising a pair of horizontal, parallel beams, and means for securing the roof to the beams comprising a plurailty of load-sustaining members organized with each beam and being severally adjustable vertically and longitudinally of the beams, each of said load-sustaining members being equipped with a device for engaging the roof at a variable point on the periphery of the roof, and means arranged with each load-sustaining member for locking it in adjusted position to the beam with which it is organized.

5. A support for a furnace roof comprising a cantilever beam, and means for suspending the roof to the beam comprising a plurality of loadsustaining tension members severally adjustable vertically and horizontally of the beam and severally provided with devices adjustable along the periphery of the roof for engaging said tension members thereto, and means for severally locking the adjusted load-sustaining members to said beam and roof.

6. A support for a furnace roof comprising a plurality of parallel cantilever beams, and means for suspending the roof from the beams comprising a plurality of load-sustaining members organized with each beam, each of said members being severally adjustable vertically and longitudinally of the beam, with which it is organized and being provided with means for looking it to the beam in adjusted position, a device carried by each member for engagement with the roof, said device being adjustable along the periphery 7 of'the roof, and means for locking the device to the roof in adjusted position on the periphery thereof.

7. A support for a furnace roof that includes in structure a peripherally extending flanged metal skew-back supporting a dome of refractory material, said support comprising a plurality of parallel horizontal beams, a plurality of loadsustaining members suspended in spaced-apart relation from each of said beams and adjustable vertically and longitudinally of the beams, means for severally locking the members in adjusted positions on the beams, and a device on the lower end of each of said suspended members for engaging the flange of said skew-back, each of said devices being adjustable peripherally of the engaged skew-back and arranged to be locked to the skew-back in adjusted position.

8. A support for a furnace roof that includes in structure a peripherally extending flanged metal skew-back supporting a dome of refractory material, said support comprising a plurality of parallel horizontal beams, a plurality of loadsustaining members suspended in spaced-apart relation from each of said beams and adjustable vertically and longitudinally of the beams, said members severally comprising threaded shanks equipped with nut elements for clamping the members in adjusted positions on the beams, and a clamp on the lower end of each threaded shank engaging and being adjustable longitudinally of the flange of said skew-back.

9. In an electric furnace having a roof of refractory material supported by a flanged skewback and a plurality of horizontal beams for supporting the roof of the furnace, and means for raising and lowering said beams and swinging them in a horizontal plane; means for adjustably securing the furnace roof to said beams which comprise a plurality of load-sustaining members suspended in spaced-apart relation from each of said beams, said members severally comprising threaded shanks equipped with nut elements for clamping the members in adjusted positions on the beams, and a clamp on the lower end of each threaded shank engaging and being adjustable longitudinally of the flange of said skew-back to vary the supported position of said roof.

10. In an electric furnace having a plurality of horizontal beams for supporting the flanged metal the slot in the beam with which it is organized, a

pair of nut elements on said shank for clamping the associate beam and providing for the adjustment of the shank vertically and longitudinally of the beam, and a clamp on the lower end of said shank adjustable peripherally of and engageable to the flange of said roof-ring.

11. A support for a furnace roof having a flanged skew-back, said support comprising a horizontal beam, and means for securing the skew-back of the roof to said beam comprising a load-sustaining threaded shank adjustable vertically and longitudinally of the beam and provided at its lower end with a device adjustable along the periphery of the skew-back, means at the upper end of said shank for rotating the shank to lock said device to the skew-back, and a pair of nut elements on said shank for clamping said shank in vertically adjusted position to said beam.

WILLIAM ENOCH MOORE.

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 431,012 Smythe June 24, 1890 1,339,615 Wundrack May 11, 1920 1,420,561 Leander June 20, 1922 1,488,576 Waite Apr. 1, 1924 1,629,668 Lenk 1 May 24, 1927 1,730,667 Lorino Oct. 8, 1929 1,846,178 Bergren Feb. 23, 1932 1,877,781 Akerlund Sept. 20, 1932 1,976,595 Asleson Oct. 9, 1934 2,114,230 Moore Apr. 12, 1938 2,182,675 Morton Dec. 5, 1939 2,200,372 ,Linder May 14, 1940 2,299,102 McLimans Oct. 20, 1942'