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US1420561A - Electric furnace - Google Patents

Electric furnace Download PDF

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Publication number
US1420561A
US1420561A US382673A US38267320A US1420561A US 1420561 A US1420561 A US 1420561A US 382673 A US382673 A US 382673A US 38267320 A US38267320 A US 38267320A US 1420561 A US1420561 A US 1420561A
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United States
Prior art keywords
furnace
frame
roof
furnace body
electric
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Expired - Lifetime
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US382673A
Inventor
Leander Knut
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LUDLUM ELECTRIC FURNACE Corp
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LUDLUM ELECTRIC FURNACE CORP
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Priority to US382673A priority Critical patent/US1420561A/en
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D11/00Arrangement of elements for electric heating in or on furnaces
    • F27D11/08Heating by electric discharge, e.g. arc discharge
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27BFURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B3/00Hearth-type furnaces, e.g. of reverberatory type; Electric arc furnaces ; Tank furnaces
    • F27B3/08Hearth-type furnaces, e.g. of reverberatory type; Electric arc furnaces ; Tank furnaces heated electrically, with or without any other source of heat

Definitions

  • My invention relates to electric furnaces. and particularly to furnaces of the general type shown in the patent to Trembour, Lam-ram, dated l ⁇ l:ll'(fli 1c. 1920.
  • the 0b ect of my invention is to facilitate the operation of the furnace by so constructing the latter as to permit the withdrawal of the furnace bodv from beneath the roof which carries the electrodes, and particularly to improve the general construction and arrangement of parts by which this is rendered possible.
  • Fig. 1 is a side elevation of a furnace in which my invention is embodied in one form
  • Fig. 2 is a similar view showing the body of the furnace withdrawn from beneath the roof;
  • Fig. 3 is an end elevation of the furnace in the position shown in Fig. 1; v
  • Fig. 4 is a side elevation showing th furnace tipped for pouring the charge.
  • Fig. 5 is a diagram illustrating a general installation embodying the invention.
  • the invention may be applied to furnaces of different types I- have illustrated it embodied in a furnace of the type shown in the Trembour patent. above mentioned, with the understanding that the construction may be varied in many ways. not only with respect to thepresent type of furnace, but
  • the furnace bodyylo comprises a metal shell with the usual refractory lining 11 to form a hearth of generally ovoid shape with bottom upwardly lnclined to the door openings 12 at the oppositeends of the furnace chamber.
  • the shell has secured thereto vertical angle irons 13 and 14 at each end, the angles 14 extending slightly above the sides of the furnace body to afford guides which aid in properly positioning the furnace roof thereon. Between the angles extend horizontal beams .15 which support bearings 16 for running wheels 17 on which the body 10 of the furnace is su Tracks 1 8lead from the furnaceandpermit Specification of Letters Patent.
  • Uprights 31 on the frame are united at their upper ends by cross beams 32, and by intermediate cross beams 33, forming an open' frame work of generally rectangular shape.
  • the furnace roof 34 is arranged within the upper portion of the frame and comprises refractory brick arches springing from the side beams 35 and tied at the ends by arched cross beams 36.
  • Stirrups 37 secured to the longitudinal side beams at suitable points, preferably toward the opposite ends of the furnace, receive eye bolts 38 connected by adjusting turn buckles 39 to cables 40, by which the roof is suspended in the frame.
  • the four cables pass around their respective sheaves 41 to a common guide sheave 42, and thence to one end of a draw bar 43, to which they are, all secured.
  • the latter is provided at its'opposite end.
  • r plate 47 arranged on the inner face of the frame adjacent the motor protects the latter from heat injury when the furnace roof is lifted to permit the furnace body to be run out for recharging, or other purposes.
  • brackets 48 On the opposite side of the frame from the lifting motor 45 are brackets 48 carrying guides 49 for the vertically movable slides 50. Secured to the upper ends of the latter are electrode arms 51 carrying clamps 52, in which are supported the electrodes 53 which pass down through the roof of the furnace into the furnace chamber. The feed and adjustment of the electrodes during the operation of the furnace are secured by raising and lowering the slides 50 by any suitable mechanism, automatically or manually operated. Current is led to the electrodes through flexible connections 54.- extending from fixed terminals 55 to the respective electrode arms 51.
  • the switch controlling the current to the electrodes is located at 56, at one side of the furnace, and adjacent the switch 56 is a second switch 57 controlling the current'for the roof lifting motor 45. The operator may thus, from a single position, not only control the operation of the furnace, but also the lifting and lowering of the roof.
  • Fig. 3 I have shown one of the cooling pots 58, through which the electrodes enter the furnace roof. These pots are preferably suspended by cables 59 from the electrodearms 51, and are fed through flexible tubing 60 leading to the water circulating source.
  • Fig. 1 I have indicated at one end of the furnace the lever 61 for lifting and lowering the door 62, which closes the end openin 12 during the operation of the furnace. he lever is pivoted at 63 on the frame, and is extended inward to the counterweight 64. A cable 65 connects the door to the lever.
  • Fig. 5 I have diagrammatically illustrated a general installation in which this furnace is adapted to be used.
  • the track 18 is connected by a transfer table 66 with a second track 67 passing beneath a preheating hood 68 under which the car may be moved after it'has been charged at 69, or elsewhere, with scrap.
  • the charge of cold scrap may be here preheated to a hot or semi-melted condition by any suitable means, such as a gas flame or the like.
  • the furnace body neath the roof 34 and the latter lowered to adjusted position, after which the completion of the melting and refining process is effected throu' h the 'electric current.
  • the present construction offers the great advantage of expediting the charging of the furnace, since by bringing the furnace body from beneath the roof 34 it is possible to place the fresh charge in the bottom much more readily and rapidly than in the customar fashion of introducing it piece by piece t rough the door open is then run be-.
  • An electric furnace comprising independent body and roof elements, a frame in which the roof issupported and vertically adjustable, means on which the furnace body may be travelled into and out of position beneath the roof, electrodes passing through the roof to the furnace and supported by the frame, and means for tilting the frame and the furnace body, roof and electrodes supported thereby, to discharge the furnace.
  • a tilting frame adjustable therein, and a furnace body movable into and out of position beneath the roof and between the illustrates a 3.
  • a tiltable frame having means for supporting a furnace body in the lower portion thereof and between the side members of the frame, a. super-structure for said frame, and means for suspending and vertically adjusting the roof in said super-structure, substantially as described.
  • a tiltable frame having means for supporting a furnace body in the lower portion thereof and between the side members of the frame, a super-structure for said frame, and means for suspending and vertically adjusting the roof in said super-structure, together with means associated with said support for leveling the roof with respect to the furnace body.
  • a frame adapted to support a furnace body, a roof vertically adjustable on. said frame, and an electric motor mounted on the side of said frame for lifting and lowering the roof.
  • a frame adapted to receive and support a removable furnace body, a furnace roof vertically adjustable on said frame to lift and lower the same with respect to the furnace body, and a readily detachable connection between said lifting and lowering means and the furnace roof to permit the roof to be withdrawn from the frame with the furnace body.
  • a frame In an electric furnace, a frame, an associated furnace body movable into and out of position on said frame, a furnace roof vertically adjustable in said frame with respect to the furnace body and means for tilting said frame to discharge the furnace while temporarily supported thereby.
  • a frame In ill'lBlGCtllC furnace, a frame, a furnace body movable into and out of position thereon, a furnace roof vertically adjustable in said frame with respect to said furnace body, electrodes carried by said frame, and means for tilting the frame with its associated elements to discharge the furnace.
  • a frame a furnace body movable into and out of position with respect to said frame, a furnace roof vertically adjustable in said frame, elec trodes carried by said frame, flexible connections leading to said electrodes, and
  • a frame a furnace body movable into and out of operating position with relation thereto, a furnace roof vertically adjustable in said frame above said furnace body, a motor mounted on said frame, means associated with said motor for lifting and lowering the furnace roof, and means arranged in fixed position below said frame and furnace body for tilting said frame and associated elements to discharge the furnace.
  • a frame In an electric furnace installatidn, a frame, tracks thereon, a wheel supported furnace body running into and out of position on said tracks carried by the frame a vertically adjustable roof carried by said frame, means for tilting said frame to discharge the furnace while supported thereon, and means for maintaining said furnace body on said tracks during the tilting of the frame.
  • v p v 12 In an electric furnace installation, a tilting frame, a furnace body adapted to be supported thereby, a roof vertically adjustable on said frame, tracks leading to the frame to permit the furnace body to be run into and away from the frame and guided with relation thereto.
  • a tilting frame In an electric furnace installation, a tilting frame, a furnace body adapted to be supported thereby, a roof vertically adjustable on said frame, tracks leading to the frame to permit the furnace body to be run into and away from the frame and guided with relation thereto, together with a preheater beneath which the furnace body ma be run on said tracks to preheat a fres charge therein.
  • a hearth In an electric furnace, the combination of a hearth, a roof, a frame for the roof, lifting devices engaging opposite ends of the frame and movable upwardly to raise the roof clear of the hearth, and means for shifting the hearth.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)

Description

K. LEANDER.
ELECTRIC FURNACE.
APPLICATION FILED MAY 19, 1920.
1,420,56 1 Patented June 20, 1922.
5 SHEETS-SHEET l- INVENTOR Krvur LEfl/VZIER K. LEANDER.
ELECTRIC FURNACE.
APPLICATION FILED MAYI9, r920.
1,420,561. Patented June 20,1922.
5 SHEETS-SHEET 2.
IN VENTOR KNUT LEH/YDEK K. LEANDER.
ELECTRIC FURNACE.
APPLICATION FILED MAY 19, 1920.
Patented June 20; 1922.
5 SHEETSSHEET 4.
x4 m E 7 0 N w 1 E E y L m N j m KM. B 1;?
APPLICATION FILED MAY 19, 1920.
K. LEANDER. ELECTRIC FURNACE.
Patented June 20, 1922.
5 SHEETSSHEET 5.
INVENTOR Kn'u-r LE/FNDER vmw unrrso STATES rarsnr orrics.
KNUT LEANDER, OF ALBANY. NEW YORK, ASSIGNOR TO LUDLUM ELECTRIC FURNACE CORPORATION, OF WATERVLIET. NEW YORK. A CORPORATION OF NEW YORK.
ELECTRIC Application filed ma 19,
T 0 all to 710m it may concern Be it known that l. Knr'r LEANDER, a subject of the King of Sweden, residing at Albany, in the county of Albany and State of New York, have invented certain new and useful Improvements in Electric Furnaces, of which the following is a specification.
My invention relates to electric furnaces. and particularly to furnaces of the general type shown in the patent to Trembour, Lam-ram, dated l\l:ll'(fli 1c. 1920. The 0b ect of my invention is to facilitate the operation of the furnace by so constructing the latter as to permit the withdrawal of the furnace bodv from beneath the roof which carries the electrodes, and particularly to improve the general construction and arrangement of parts by which this is rendered possible.
Fig. 1 is a side elevation of a furnace in which my invention is embodied in one form;
Fig. 2 is a similar view showing the body of the furnace withdrawn from beneath the roof;
Fig. 3 is an end elevation of the furnace in the position shown in Fig. 1; v
Fig. 4 is a side elevation showing th furnace tipped for pouring the charge; and
Fig. 5 is a diagram illustrating a general installation embodying the invention.
\Vhile the invention may be applied to furnaces of different types I- have illustrated it embodied in a furnace of the type shown in the Trembour patent. above mentioned, with the understanding that the construction may be varied in many ways. not only with respect to thepresent type of furnace, but
also to adapt it'as may be necessary to other types of furnace construction. As here. shown, however, the furnace bodyylo comprises a metal shell with the usual refractory lining 11 to form a hearth of generally ovoid shape with bottom upwardly lnclined to the door openings 12 at the oppositeends of the furnace chamber. The shell has secured thereto vertical angle irons 13 and 14 at each end, the angles 14 extending slightly above the sides of the furnace body to afford guides which aid in properly positioning the furnace roof thereon. Between the angles extend horizontal beams .15 which support bearings 16 for running wheels 17 on which the body 10 of the furnace is su Tracks 1 8lead from the furnaceandpermit Specification of Letters Patent.
ported.
FURNACE.
Patented June 20, 1922.
1920. Serial No. 382,673.
- furnace roo and also to support the furnace body when the furnace is tilted, as shown in Fig. 4, upon the pour of the finished charge. The tilt of the furnace is accomplished by links 27 pivoted at one end to the stringer 28 of the frame, and at the other end to cranks on the shaft 29 driven through gear 30 from any suitable power connection.
Uprights 31 on the frame are united at their upper ends by cross beams 32, and by intermediate cross beams 33, forming an open' frame work of generally rectangular shape. The furnace roof 34 is arranged within the upper portion of the frame and comprises refractory brick arches springing from the side beams 35 and tied at the ends by arched cross beams 36. Stirrups 37 secured to the longitudinal side beams at suitable points, preferably toward the opposite ends of the furnace, receive eye bolts 38 connected by adjusting turn buckles 39 to cables 40, by which the roof is suspended in the frame. The four cables pass around their respective sheaves 41 to a common guide sheave 42, and thence to one end of a draw bar 43, to which they are, all secured.
The latter is provided at its'opposite end.
with a screw bolt engaged in an internally threaded gear 44 driven by the motor 45 mounted on a bracket 46 (Fig. 3) extending outward from one side of the frame. r plate 47 arranged on the inner face of the frame adjacent the motor protects the latter from heat injury when the furnace roof is lifted to permit the furnace body to be run out for recharging, or other purposes.
On the opposite side of the frame from the lifting motor 45 are brackets 48 carrying guides 49 for the vertically movable slides 50. Secured to the upper ends of the latter are electrode arms 51 carrying clamps 52, in which are supported the electrodes 53 which pass down through the roof of the furnace into the furnace chamber. The feed and adjustment of the electrodes during the operation of the furnace are secured by raising and lowering the slides 50 by any suitable mechanism, automatically or manually operated. Current is led to the electrodes through flexible connections 54.- extending from fixed terminals 55 to the respective electrode arms 51. The switch controlling the current to the electrodes is located at 56, at one side of the furnace, and adjacent the switch 56 is a second switch 57 controlling the current'for the roof lifting motor 45. The operator may thus, from a single position, not only control the operation of the furnace, but also the lifting and lowering of the roof.
In Fig. 3 I have shown one of the cooling pots 58, through which the electrodes enter the furnace roof. These pots are preferably suspended by cables 59 from the electrodearms 51, and are fed through flexible tubing 60 leading to the water circulating source.
In Fig. 1 I have indicated at one end of the furnace the lever 61 for lifting and lowering the door 62, which closes the end openin 12 during the operation of the furnace. he lever is pivoted at 63 on the frame, and is extended inward to the counterweight 64. A cable 65 connects the door to the lever.
In Fig. 5, I have diagrammatically illustrated a general installation in which this furnace is adapted to be used. As here indicated, the track 18 is connected by a transfer table 66 with a second track 67 passing beneath a preheating hood 68 under which the car may be moved after it'has been charged at 69, or elsewhere, with scrap. The charge of cold scrap may be here preheated to a hot or semi-melted condition by any suitable means, such as a gas flame or the like. After the charge has. been preheated the furnace body neath the roof 34 and the latter lowered to adjusted position, after which the completion of the melting and refining process is effected throu' h the 'electric current. It will be noted t at the tracks 18 extends beyond the transfer table 66, so that the empty bottom, from the pouring position, may be got out of the way while the rechar ed bottom or furnace bod is being shi ted from the preheater an run beneath the lifted furnace roof.
Whether or not a preheating hood, or the like, be used, the present construction offers the great advantage of expediting the charging of the furnace, since by bringing the furnace body from beneath the roof 34 it is possible to place the fresh charge in the bottom much more readily and rapidly than in the customar fashion of introducing it piece by piece t rough the door open is then run be-.
lining, since it may be lowered by an electro- -magnet directly to thefurnace bottom without shock or mechanical injury to the lining.
Again, by using a plurality of furnace bodies with a single roof, it is possible to proceed with the refining of the metal electrically in one furnace body, while a second body is being charged and preheated. This materially adds to the capacity of a relatively small plant, since the refining operation can be made practically continuous. Obviously, furthermore, the construction makes it possible to repair the lining of both the furnace body and of the roof much more conveniently than has heretofore been the case.
The construction shown simple, workable embodiment of my invention, but. as previously stated, it is possible to vary the details in many ways, and I do not limit my invention to the particular type of furnace shown, or to the construction described.
I claim- 1. An electric furnace comprising independent body and roof elements, a frame in which the roof issupported and vertically adjustable, means on which the furnace body may be travelled into and out of position beneath the roof, electrodes passing through the roof to the furnace and supported by the frame, and means for tilting the frame and the furnace body, roof and electrodes supported thereby, to discharge the furnace.
2. In an electric furnace, a tilting frame, adjustable therein, and a furnace body movable into and out of position beneath the roof and between the illustrates a 3. In an electric furnace, a tiltable frame having means for supporting a furnace body in the lower portion thereof and between the side members of the frame, a. super-structure for said frame, and means for suspending and vertically adjusting the roof in said super-structure, substantially as described.
4. In an electric furnace, a tiltable frame having means for supporting a furnace body in the lower portion thereof and between the side members of the frame, a super-structure for said frame, and means for suspending and vertically adjusting the roof in said super-structure, together with means associated with said support for leveling the roof with respect to the furnace body.
5. In an electric furnace, a frame adapted to support a furnace body, a roof vertically adjustable on. said frame, and an electric motor mounted on the side of said frame for lifting and lowering the roof.
6. In an electric furnace, a frame adapted to receive and support a removable furnace body, a furnace roof vertically adjustable on said frame to lift and lower the same with respect to the furnace body, and a readily detachable connection between said lifting and lowering means and the furnace roof to permit the roof to be withdrawn from the frame with the furnace body.
7. In an electric furnace, a frame, an associated furnace body movable into and out of position on said frame, a furnace roof vertically adjustable in said frame with respect to the furnace body and means for tilting said frame to discharge the furnace while temporarily supported thereby.
8. In ill'lBlGCtllC furnace, a frame, a furnace body movable into and out of position thereon, a furnace roof vertically adjustable in said frame with respect to said furnace body, electrodes carried by said frame, and means for tilting the frame with its associated elements to discharge the furnace.
9. In an electric furnace, a frame, a furnace body movable into and out of position with respect to said frame, a furnace roof vertically adjustable in said frame, elec trodes carried by said frame, flexible connections leading to said electrodes, and
means for tilting said associated furnace roof and electrodes to discharge the furnace without breaking the electrode connections.
10. In an electric furnace, a frame, a furnace body movable into and out of operating position with relation thereto, a furnace roof vertically adjustable in said frame above said furnace body, a motor mounted on said frame, means associated with said motor for lifting and lowering the furnace roof, and means arranged in fixed position below said frame and furnace body for tilting said frame and associated elements to discharge the furnace.
11. In an electric furnace installatidn, a frame, tracks thereon, a wheel supported furnace body running into and out of position on said tracks carried by the frame a vertically adjustable roof carried by said frame, means for tilting said frame to discharge the furnace while supported thereon, and means for maintaining said furnace body on said tracks during the tilting of the frame. v p v 12. In an electric furnace installation, a tilting frame, a furnace body adapted to be supported thereby, a roof vertically adjustable on said frame, tracks leading to the frame to permit the furnace body to be run into and away from the frame and guided with relation thereto.
13. In an electric furnace installation, a tilting frame, a furnace body adapted to be supported thereby, a roof vertically adjustable on said frame, tracks leading to the frame to permit the furnace body to be run into and away from the frame and guided with relation thereto, together with a preheater beneath which the furnace body ma be run on said tracks to preheat a fres charge therein.
14. In an electric furnace, the combination of a hearth, a roof, adjustable electrodes passing through the roof, a common support for said electrodes and roof, and means for raising the roof from the hearth.
15. In an electric furnace, the combination of a hearth, a frame, a roof carried by the frame, and means for lifting said frame, said lifting means being disengageable from the frame.
16. In an electric furnace, the combination of a hearth, a frame, a roof carried on said frame, lifting means engaging opposite side members of the frame, and associated means to prevent tilting of the roof in lifted position.
17. In an electric furnace, the combination of a hearth, a frame, a roof carried on said frame, lifting devices engaging the frame, and screw means for operating said lifting devices.
18. In anelectric furnace, the combination of a hearth, a frame, a roof carried on said frame, lifting devices engaging the frame, and screw means for operatm said lifting devices, together with an e ectric motor for driving said screw means.
19. The combination of a track, a traveller mounted for movement thereon, a furnace on the traveller, a removable roof, and means for raising the roof, said means being located at such point as to permit the traveller being shifted to clear the furnace from the roof.
20. In an electric furnace, the combination of a hearth, a roof, a frame for the roof, lifting devices engaging opposite ends of the frame and movable upwardly to raise the roof clear of the hearth, and means for shifting the hearth.
In testimony whereof I have signed my name to this specification.
US382673A 1920-05-19 1920-05-19 Electric furnace Expired - Lifetime US1420561A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2472954A (en) * 1944-05-12 1949-06-14 Delaware Engineering Corp Adjustable roof mounting means for top charged electric furnaces
US2528571A (en) * 1948-05-22 1950-11-07 Nat Supply Co Electric tilting furnace
US2535622A (en) * 1941-07-12 1950-12-26 Pour L Ind Du Magnesium Soc Et Production of metal from its ore
US4468781A (en) * 1980-10-09 1984-08-28 Bbc Brown, Boveri & Company Limited Tiltable arc furnace

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2535622A (en) * 1941-07-12 1950-12-26 Pour L Ind Du Magnesium Soc Et Production of metal from its ore
US2472954A (en) * 1944-05-12 1949-06-14 Delaware Engineering Corp Adjustable roof mounting means for top charged electric furnaces
US2528571A (en) * 1948-05-22 1950-11-07 Nat Supply Co Electric tilting furnace
US4468781A (en) * 1980-10-09 1984-08-28 Bbc Brown, Boveri & Company Limited Tiltable arc furnace

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