US1857103A - Lining for furnaces - Google Patents

Description

May 3, 1932. R P. SOUTH LINING FOR FURNACES INVENTOR Filed March 22, 1929 Patented May 3, 1932 UNITED STATES PATENT OFFICE- RICI-IARD P. SOUTH, F CLEVELAND, OHIO, ASSIGNOR T0 LAVA CRUCIBLE COMPANY OF PITTSBURGH, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENN- SYLVANIA LINING 'FOR FURNACES Application inea March 22, 1929. seriaifno. 349,169. y Y

This invention relates to linings for furnaces or the like, and more particularly to metal melting furnaces of the cylindrical horizontally disposed rotatable type, wherein slag is formed during the melting operation and in which the melting is effected by heat from an oil or gas blast passing over the contained metal or by heat from an electric arc.

The linings for such furnaces as heretofore employed have been the source of considerable trouble on account of the high temperatures, particularly above the molten metal, and the action of the metal and slag on the lining.

The prime object of the present invention is to provide a cylindrical furnacelining of the character specified, comprising a portion formed of a high temperature-resistant refractory, and a lower or metal-receiving portion formed of a slag resistant and chemicalresistant refractory.

Additional objects will become apparent from the following description taken in connection with the accompanying drawings, wherein:

Fig l is a longitudinal vertical sectional View ofV a cylindrical furnace embodying my invention;

Fig. 2, a sectional view taken at right angles to the view of Fig. 1; and

Fig. 3, a'view similar to Fig. 2, showing a inodied form of furnace.

Referring to the drawings, the furnace in general comprises a cylindrical metal casing 5 provided with a cylindrical lining 6. Casing 5 is separated from said lining by a layer of insulating material 7, such as fire clay or the like.

As shown and as preferred, the lining body 6 is an integral unit formed of two materials, the upper portion A being formed of a refractory material having a high temperature resistance, and the lower portion B formed of a slag resistant and chemicalresistant refractory material; For example,

the portion A may be formed of silicon carbide and the lower portion B of mullite.

' At' its ends, the lining body 6 is provided with'annular recesses 8 to receive circular end pieces 9 constituting portions of the lining portions 8a entered inthe respective recesses and secured by a layer of cement or fire clay lO. The ,end pieces 9 consist of an upper temperature-resisting portion A and a lower slag or chemical-resisting portion B', and are further-each provided with a central opening 1l to receive hollow trunnions 12. The

furnace'is mounted in any suitable mannerV to permit rotation thereof on the said trun-` nions. f

The construction describedV is typical ofthe cylindricalor barrel-shaped furnace used in practice, principally forv melting brass or bronze. In some types, as shown inthe drawings, electrodes 13 are introduced through the hollow trunnions 121:0 yproduce an electric arc i by a refractory door, held in place by clamping and sealed with fire clay in the usual manner.

' During vthe melting,k operation, the molten metal will kbe in contact with the lower lining portions B and B of the body and the end pieces, which, due to their slag and/or chemical-resisting properties, will preventfdestruction thereof. The upper liningportions A and A will withstandthe high temperatures of the process because of their refractory properties. Thus, the-objectionable chemical action of the slag Vin the usual type of lining is not present and the region of highest c u n o u said end pieces having annular projecting lin Vtemperature is protected by portions A and A. Y

Y Upon completing the melting process, the furnace may be rotated on itstrunnions 12 to discharge the molten metal.V

In the form of Fig. 3, the furnace casing 5a is divided horizontally. Such construction provides ease of assembly, for the lining 6a may be secured in the lower half of the furnace before assembling the upper half of the casing. This form of furnace is further provided with an opening 14a in the top thereof, for charging and pouring.

It will be seen that such a furnace lining willrgive ent-ended service, lessen the frequency of shut-downs, and willprovide a lining easily changeable. Y

Various changes and modifications are contemplated, provided they fall within the scope of the following claims.`

Iclaim:V y y l. In a closed cylindrical furnace, a lining comprising a cylindrical body and annular end pieces in interiitting engagement with the Y body, the upper portion of said -c vlindrical i i i body and end pieces formed of a high temperature-resistant refractory and the lower portion of said body and end pieces coacting to Vheld molten metal and being formed of a slag-resistant refractory.

2. In a cylindrical furnace, a one-piece cylindrical lining'member, two end members cacli iii one piece interfitted into the opposite ends of the cylindrical lining member, a portion of each member being resistent to chemical att-ack of slag and jointly forming a holding means for molten metal, and the remainder of each member being of refractory material resi tant to high temperature.

In aY c ndrical furnace, a one-piece cylindrical lining member, two end members each in one piece interfittedinto the opposite ends of the cylindrical lining member, a por- .tion of each member being of mullite and the remainder being` of silicon carbide, and trimiizvons of silicon Vcarbide interfitted into the cnd members at the junction of the mullite yand silicon carbide. Y Y

'In a cylindrical furnace, a olie-piece cyical lining member, two end members each in one piece interfitted into the opposite ends of the cylindrical lining member, a portion of each member being of mullite whereby y closed construction, said furnace having a lining provided with a discharge opening in a side thereof, said lining being of a form to hold molten Vmetal and being of mullite-to a height above the base of said opening.

. 6, In a cylindrical furnace, a cylindrical lining member, two'end members interfitted y RICHARD P. soUTH. y

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