US1433404A - Electric furnace - Google Patents

Description

7 INVENTORS ATTORNEYS F. F. MUELLER AND R. W. HARRIS ELECTRIC FURNACE.

APPLICATION FILED ocr Patented 0ct. 24,1922-.

rammed. a. 24, 1922.

UNITED STATES 1,433,404 PATENT .QF L,

FREDERICK F. MUELLER AND RUSSELL W. HARRIS, OF WASHINGTQN, PENNSYL- VANIA, ASSIGNOBS TO STANDARD CHEMICAL COMPANY,-v OF PITTSBURGH,

PENNSYLVANIA.

ELECTRIC FURNACE.

Application filed October 20, 1920. Serial No. 418,162.

To all whom it may concem:

Be it known that we, FREDERICK MUEL- LER and Rnssnnr. V. HARRIS, citizens of the United States, and residents of Washington,

' in the county of WVashington and State of uranium low in carbon and silicon,one object of the invention being to provide an electric furnace with a lining which shall have high refractory qualities to withstand excessively high temperatures without deterioration; which shall not introduce into the molten bath anyelement which might contaminate the alloy; and which can be used as raw material in the construction of a new lining.

With this and other objects in view, the invention consists in certain novel features of construction as hereinafter set forth and pointed out in-the claims.

The accompanying drawing is a view in section, of an electric. furnace embodying our invention.

1 represents the shell of the furnace which may be provided with trunnlons 2 to be mounted upon a suitable support so as to be capable of tiplping to discharge the finished product. he shell 1 is hollow and may comprise steel plates so dlsposed and secured as to provide a chamber 3 between them to receive fluid, such as water, for cooling purposes. For this reason, the hollow shell may be provided with suitably located ta s 4. I

ithin the shell 1, a lining; 5 is located and the mass composing this lining is shaped to provide a furnace chamber or hearth 6 open at its upper end. The furnace shell is provided in its bottom with an opening 7 for the accommodation of a bottom electrode 8. This electrode may be made of steel and v provided with a headed upper end embedded in the material of the lining 5 below the bottom of the hearth or furnace chamber 6, and a plurality of iron wires'9 may extend from the headed end of saidelectrode to the bottom' of the hearth or furnace chamber to facilitate the starting of theo eration of the furnace when the latter an the material to be treated are cold. 3

The upper electrode 10 of the furnace which may be made of graphite, depends into the furnace chamber and is carried by suitable regulating mechanism (not shown) to permit its manipulation to establish, maintain and regulate the length of the electric are between the two electrodes and the intensity and degree of the heat to which it may be desired to subject the material under treatment during the carrying out of our improved process, may be determined and controlled by manipulation of said regulating mechanism to raise or lower said upper electrode and thus lengthen or shorten the arc. The upper electrode may have a busbar 11 clamped thereto for connection, by means of a flexible cable (not shown) to one of the terminals of a transformer, and the lower electrode may also have a bus-bar l2 clamped thereto and connected by a flexible cable (not shown) withthe other terminal of the transformer.

An important feature in the construction of the furnace resides in the character of the lining employed. This lining is composed principally of uranium oxide. WVe' mix black oxide of uranium with a binder such as tar and from five to fifteen per cent of refractory cement, such as fire clay or hytempite. The purpose of the binder and. refractory cement is to give body to the lining or to promote cohesion between the pa-rticlesof uranium oxide. Our improved lining of uranium oxide is valuable by reason of its high refractory qualities to withstand excessively high temperatures without deterioration. It will not introduce into the alloy any undesirable contamination. Should any part of the lining fall into the bath, itwill be reduced from the oxide to the metal. When it is necessary to replace a lining, the old lining may be used as part of the raw material charge, and hence there is no waste.

In employing the furnace in making fer-. ro-uranium, a suitablecharge of uranium oxide mixed with an amount of carbon necessary to reduce it is placed in the furnace.

increased (which may be accomplished by lowering the upper electrode and thus shortening the electric arc), in order'that the temperature may be raised to a degree necessary to eliminate the carbon in the bath.

The oxygen of such air as may enter the fur-i then added to the bath in the form of steel turnings or any other suitable, form.

The resultant product will be ferro-uranium low in carbon and silicon, viz., less than one per cent carbon and less than two per cent silicon.

Having fully described our invention,

Continuing this high temperature, until the carbon content of the molten uran-' ium is less than one per cent (1%), iron is What We claim as new and desire to secure by Letters-Patent, is

1. An electric furnace having therein a lining of uranium oxide.

2. In an electric furnace, the combination of a shell, a lining therein of uranium oxide forming the furnace chamber, a bottom electrode having a part embedded in said lining under the bottom of the furnace chamber, and an upper electrode entering said furnace chamber.

3. A furnace lining comprising uranium oxide combined with a binder.

4. A furnace lining comprising uranium oxide mixed with tar and a refractory cement.

In testimony whereof, we have signed this specification in the presence of two subscribing witnesses.

FREDERICK F. MUELLER. RUSSELL \V. HARRIS.

Witnesses:

CLYDE E. HOLDER, THos. J. GEARING.

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