US396992A - Charles j - Google Patents

Description

Patented Jan. 29, 1889.

(No Model.)

G. J. EAMES., y COMPOUND GRAPHITIC HEARTH FOR METALLURGIG FURNAOBS. No. 396,992.

IINTTEE STATES PATENT OEETEE.

CHARLES J. EAMES, OE NEW YORK, N. Y., ASSIGNOR TO THE CARBON IRON COMPANY, OF SAME PLACE.

COMPOUND GRPHITIC HEARTH FOR METALLURGIC FUIRNACES.

SPECIFICATION forming part of Letters Patent No. 396,992, dated January 2,9, 1889.

Application filed February 3, 1887. Serial No. 226,359. (No model.)

' to be a full, clear, and exact description of the same, reference being had to the accompanying drawing, and to the letters and iigures marked thereon, which form a part of this specification.

The object of my invention is to provide a graphitic hearth or lining for furnaces that are used in the deoXidation of iron ores in the manufacture of iron sponge, which hearth shall be so constructed that the lumps of graphite shall be held together by the forniation of iron sponge in the interstices between the lumps, forming a compact hearth and foundation which will preserve its form, thus protecting the sole-plate and walls of the furnace.

My invention has the additional object of providing a hearth ot' such solidity and strength that it will. bear the weight of the reduced metal without losing' its form or being broken or depressed, and that the reduced metal may be balled or manipulated upon the hearth without disintegrating the hearth or causing any portion of the hearth to be balled up with the metal, the effect being al ways to preserve a clean smooth hearth.

My invention is attained by Jforming the bed l or hearth of ore-reducing furnaces of lumps 0f graphite and powdered iron ore. lflitherto I thehearths of such furnaces have been formed i by mixing with graphite or plumbago various proportions of lire-clay, iire-lnick, ttc., and

forming the mixture into slabs, or plastering it on the sides and bottom of the furnace. z This form of solo or .hearth is liable to bocharge of orc or metal isliable to sink through E this sofi substance and prevent the chemical action that should take place between t-he iron ore and the carbon in the deoxidation of iron ores. Again, in such cases, when it becomes necessary to remove the metal from the furnace, the weight of the metal frequently inch to an inch thick.

' the sole or hearth of my furnace is plumbago or graphite, preferably the graphitic carbon of trade, such as is obtained at Causton, Rhode Island, and elsewhere.

The construction of my hearth is indicated in the annexed drawing, which is a longitudi nal vertical section of the same.

I prefer to make my hearth in the following manner: I place upon the sole of an ordinary reverberatory furnace a layer of graphitic carbon in the form of lumps. These lumps may be of any size that will pack well and form a comparatively level surface. I prefer, however, to use lumps of about twelve inches in thickness7 or, in other words, lumps that are of about the size of a mans head. I make this first layer of carbon from twelve to twenty-four inches in depth. After the carbon layer has been made as level. as possible I fill up the interstices between the lumps of carbon with any finely-powdered iron ore. Then I cover the entire surface of the graphitic lumps andthe iron ore with ground graphitic carbon of about the size of grains of wheat, and to adepth of from two to four inches on the level middle portion, and from three to sixinches near the sides and walls. I then raise the furnace to a temperature that will expel the moisture from the ore and graphite. lVhen the moisture has been thus expelled, I

come soittwhenheated, and the superimposed place another layer of :finely-powdered iron ore on top of the last layer of graphite, makgww... ing the layer of iron orc from about half an 9 5 Then I raisethe teinperature of the ore and graphite gradually or by degrees up to about 2,500D Fahrenheit or more, taking care not to increase the heat to such a point as to melt the ore before it has loo been deoxidized. ,lt is viimiiortant in this part of the operation that the temperature should be increased gradually from the commencement of the heating'. When these several layers of iron ore have become deoxidized and reduced into iron sponge, which will take :from three to live hours or more, I discontinue the hi gh temperati'ire, but hold sufficient heat in the furnace to keep the newly-cimvcrted iron in a soft condition. The iron sponge produced by the last heating will be found to have become so incorporated with the carbon as to form an integral compound hearth with a suitable surface oi' carbon and iron. vWhen the hearth is in this comlitio'n, I proceed to pound it with a heavy wrought-iron maul or dolly until it becomes compact and forms a solid combined graphitic and iron-sponge bottom. The hearth will then be in a form such as is represented in the annexed drawing.

a is the bottom layer of `graphitic carbon.

b represents the ironv sponge after it has been reduced from the iron ore.

o is the upper layer of graphite in finer lumps or grains intermingled with the iron sponge d. The hearth is slightly bowl-shaped, as is shownv in the drawing.

Then the hearth has been made as above described, it is then ready for use. The charge of iron ore to be deoxidized and reduced to sponge, together with the reducing` agent, is spread upon this solid compact bottom, and remains in that position until the process of deoxidation is complete and the iron is ready 'forballingz The charge will not adhere to the hearth, but can be` easily raised from oft' the hearth and balled and taken thence to the blooming-hammer. 'lhe hearth will be found to be very durable, and will not require Further manipulation until it has become worn by longl usage. 'hen this compound hearth has been worn away to any considerable extent, it can be renewed or repaired by spreading1 a fresh layer of fine `graphite and powdered iron ore on the top of the hearth, and pounding down the hearth, as before described, without cooling` off the furnace.

that I claim as new, and desire to secure by Letters Patent, is-

A hearth or sole for furnaces for deoxidiz.- ing or reducing iron ores, composed of lumps of `graphitic carbon and iron sponge between the lumps, the carbon and the sponge being compact and integral with each other, substantially as shown and described.

CHARLES J. EAMES.

'tiiesses:

R. N. KENYON, W. H, KENYON.

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