US881517A - Electric furnace. - Google Patents

Description

' 'PATENTED MAR.10, 1908.

c. B. WILSON. ELECT-RIG FURNACE. APPLICATION FILED SEPT 15 1906 2 EHEETS-SEEET l.

lhz/erpiafi' M662 M070, v

- (@ywwww PATENTED MAR. 10, 1908;

C. E. WILSON. ELECTRIC FURNACE.

APPLIOATION FILED SEPT. 15,1906.

2 SHEETS-SHEET 2.

I men/Z 0 Wlsam inciting receptacle or crucible haying coin (FiARLlDS l5 WILSUN, Ol

PATEINT OFFICE.

lrlrlltllllS, WES, VlllOlbliA.

ELECTRIC FURNACE.

Specification of Letters Patent.

Patent-ed March. I 0, 1908.

Application filed September 15, 1906. Serial No. 334;,749.

T 0 all whom may concern:

Be it known that l, LT-init ates it. bison, n

citizen. of the limited States, residing at Ferris, in the county of Fayette end State of l/Vest Virginie. have invented u new and useful Iuun'oveinent in which the following u.- specification.

My invention relates to improvement in electric smelting furnaces pencrslly, and more psrticulsrly to such lurnsces 'for the treat merit of suitably mixed ore charges for the production. cl pig-iron, or steel direct.

My objects to provide lurnnce in. which the wearing u-Wey ol' the electrodes will be nmteriully reduced, and to provide e furnace of the t in named. of generally im proved. construction for use, more especially, in turning out substantially uniform prod nets of high grade.

In carrying out my invention I. provide it para-tively large stationery electrodes and provided with i'ueens for tilting it to regulate the heat-generating resistance between the electrodes; and I also provide it reedily udjustable, as well ren'iovsble, exciting elec trode for use in starting the smelting operation. I ilurtheruiore provide electrically no tuated controllers, preferably automatic in. operation, for governing the tilting of the crucible and the movement ol the exciting electrode, whereby the beet-generating resistance in the crucible mey be rendered 001') stently under substiuitially perlect control.

in the drawings- Figure 1 is u partly broken, sectional 0 love tion and diugrrun in eltic View cl :1 tilting crucible-lurneoe cmistructcd with in y iuugro'venieuts; and Fig. 2,. {L11 end elevation ol. the seine.

The crucible, 3, is preferably rectangular in cross-section. It is formed with a suitably insulated base-plate, 4-, pivotzrlly mounted, centrally toward opposite sides, on triuinions, 5, jourmiled in suitable supports, 6. It has lire-brick side-wells and mid-plates, 7, se

- cured together as by means ol end bars, 8.,

'from the plates 7 by strips 8".

The bars 8 are insulated The front inner wall is of graphite or other suitable car boneceous' materiel lorn'iinp; an electrode 12,

and tie-bolts, 9.

resting upon the refractory bottom 10; end

extending through the front well just above the bottom 10 is u tap-hole 1'! provided with a spout. Extending; across the opposite end of the chamber is clock or mess, 13, of

graphite or other c arboneceous materiel for1nitlectric l urnaces, ol-

{ ing part of the bottom at that end, as indicated, and serving as the second permanent. electrode.

Connected with the base-plate portion, 4, is menus .l'or rocking the crucible on its trunnions consisting ol u cable, 14, uttuchod. to the base-plate and running over upper and lower pulleys, l5. Between the pulleys the cable is wound around a drum, 16, forming part of at suitable electric controller device, not shown. Running on e trucl ,.17, centrally above the crucible, traveling head or trolley, 1-8, connected at one side to a cable 19, running over a. pulley, 20, and carrying a counter-weight, 21, and connected at its opposite side With a cable, 22,.running over a pulley, 23, and connected Wltll'Et drum, 24, which may be and'preierebly is a part of a controller device actuated by an electric current.

25 is a, carbon holder or'head suspended from a pulley, 26, on e raising and lowering cable, 27, extending under the pulley, 26, and over pulleys on the trolley, 18. It is l'ust'ened at one end to a bar, 38, and extends ltl', its opposite end over a pulley, 29, to the drum, 30, of another electric controller device. Extending from u busber, 31, are loads, 32, 32, con'ununiceting through the udjeccnt plate, 7, with the carbon electrode, l3; and extending from a bushel, 33, are lends, 34, communicating with the electrode, 12, through the plate, 7, at that end. Lead wires, 35, extend from the bus-bar, 33, to the carbon holder, 25. Suitably fastened at its upper end or edge to the holder, 25, is on exciting electrode in the form of a graphite plate, 36, which may be nearly as wide as the crucible chamber, as indicated in Fig. 2. y In operation the tap-hole 11 is plugged and the crucible caused initially to extend upright, as shown. The exciting electrode, 3 is lowered into the crucible to the elec-. trode 12' the current then turned on and the electrode 36 then raised slightly to produce the initial heat-generating are between it and the lower portion of the electrode 13. Ore led into the crucible becomes molten at the direction of the electrode 12. metal accumulates the exciting electrode 36 is moved slowly, toward theelectrode 12, to keep it at its lower edge in such, relation to the advancing stream of metal as to mainbetween tho/nu the said ere, and tends to spread and llow in As molten.

tain the necessary heat-generating resistance I fining, preferably water-jacketed, insulated cover, indicated by the dotted lines, 37, may be placed upon the crucible, the cover having a suitable opening through which 1 1c ore charge may be fed to the crucible.

l/Vhen, as stated, the molt-en metal has accumulated to an extent sufficient to spread entirely across the refractory base 10 from the edge of the electrode 13 to the lower edge of the electrode 12, the consequent free pas sage of the current and lowering of the resistance causes the electric-controller to turn the drum 16 and tilt the crucible to the left,

in Fig. 1, until the molten metal recedes from the electrode 13 far enough to reestablish the resistance which the controller is intended to maintain. Thus as the uantity of molten metal mcreases the cruel le becomes tilted -more and more until the metal extends in in a plane, from close to the lower edge of the electrode 13 more or less nearly to the top of the electrode, 12. The plug is then removed from the tap-hole 11, and first the metal which has separated by gravity from the'slag flows through the tap-hole and then the slag. As the pouring olf progresses the bath of metal'tends to recede from the lower edge of the electrode 13. This causes the controller to reverse its former operation, in its endeavor to maintain the proper resistance, and to turn' the crucible in the direction of its upright position shown. When the surface of the metal sinks below the top of the.

ta hole, molten slag W1 1 pour off.

The controllers, .16, 24 and 30, are not specifically shown and described in the pres ent application, and may be dispensed with if desired and the operation of tilting the crucible and moving and raising and lowering the exciting electrode performed by hand or other means. The controllers 1 prefer to employ may be of known construction and electrically actuated and governed in their operations by the resistance to the current passing through the furnace. As the molten mass cecumulates and resistance diminishes between the molten met... and electrode 13, the controller, 16, would turn to tilt the crucible forward. The controllers,

overlying the metal 24 and 30, would operate to raise the exciting electrode during the initial starting of the operation and move it toward the electrode, 12. In this way approximately constant, uniform resistance and hcat-gcucration may be maintained, which would aid materially in the production of a uniform metal product.

if desired plugged tap-holes at different i l l,

elevations for slag and metal may be provided in place of the one pouring opening, 11, at that end, whereby at the end of a run the slag and metal may be tapped off separately in a well known marmer.

The exciting electrode, 36, need be em ployed only for a comparatively short time at the beginning of a run after a complete shut down and the wear thereon would thus be comparatively little. The electrodes, 12, 13, being comparatively large bodies of carbonaceous material, will permit large units of electric current to be employed and lthe1 wear thereon will also be comparatively itt e.

What I claim as new and desire to secure by Letters Patent is 1. In an electric furnace, the combination of a melting-receptacle provided with main electrodes, and an exciting electrode movable betweenthe main electrodes, to-

ward one and away from the other, for the main electrodes, and an inserti le and withdrawable exciting electrode with-means for moving it between the main electrodes,

toward one and away from the other, for the purpose set forth.

3. In an electric furnace, the combination of. a melting-receptacle provided with main electrodes, an msertible and withdrawable exciting electrode and an electric controller device operatively connected with the exciting electrode for moving the same between the main electrodes, toward one and away from the other, for the purpose set forth.

4. In an ore smelting electric furnace,

the combination of a tiltable melting-receptacle provided with electrodes toward opposite sides, and means for tilting the re ceptacle to prevent accumulating molten metal from contacting with one electrode and to maintain the desired resistance through the heat-generating material overlying the metal.

-5. In an ore-smelting electric furnace, the combination of a tiltable melting-receptacle provided with electrodes toward opposite sides, and an electrically actuated controllcr device operatively connected with the receptacle for tilting the same, to prevent accumulating molten metal from contac'ting with one electrode and to maintain thc desired-resistance throu h the heatgenerating material overlying the metal.

6. in an ore-smelting electric furnace, the combination of a tiltable melting-receptacle provided with main electrodes toward opposite sides, an exciting electrode, means for moving the exciting electrode toward one of the said main electrodes and away from the other, and means for tilting the receptacle cumulates therein, for the purpose set forth.

fs. In on. ore-smelting electric furnace, the comhmatnin ol n liltzible melting-receptacle provided in one side with a pouring opening and in. opposlte sides with electrodes, means for tilting the receptacle in one direction to prevent accumulating molten metal from contacting with one electrode and to maintain the desired resistance through the heatgenerating material overlying the metal, the receptacle being tiltalole in the opposite direction to retain the desired resistance as the molten contents (,lischarge through the said pouring opening.

CHARLES E. WILSON.

vIn the presence of- H. M. GIBBES, TI R. RAGLAND.

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