US1115263A

US1115263A - Metallurgical furnace.

Info

Publication number: US1115263A
Application number: US75059613A
Authority: US
Inventors: Utley Wedge
Original assignee: Individual
Current assignee: Individual
Priority date: 1913-02-25
Filing date: 1913-02-25
Publication date: 1914-10-27
Anticipated expiration: 1931-10-27

Description

U. WEDGE. METALLURGIGAL FURNAGE. APPLIGATION FILED FBB.25,1913.

Pamemd @$211914 METALLURG-IGAL F'RNACE.

Application ined February 25,

' which the following is a specification.

My invention relates to a furnace of the superposed hearth type having rabbles which are carried by and depend from the hearths.

My invention relates particularly to a small furnace of this type intended for lab oratory use, the objects of my invention being to so construct such a furnace as to' keep the cost of the same within reasonable limits, to minimize the height of the furnace consideringthe number of hearths therein, to provide simple and eiieient means for carrying the hearths and for rotating such of the same as have to be rotated; to provide for the ready insertion and removal of the rabbles; and to permit of the use of the furnace without discomfort in a closed room.

The objects I attain in the manner hereinafter set forth reference being had to 'the accompanying drawing which represents a vertical sectional 'View of a furnace constructed in accordance with my invention.

In the drawing, I have shown afurnace having nine hearths numbered consecutively from top to bottom of the furnace, the hearths l, 3, 5, 7, and 9 being fixed hearths mounted in the outer wall of the furnace and the

hearths

2, 4, 6 and 8 beingrotatinghearths which are carried by a central shaft l() mounted in a suitable step bearing below the furnace and intended to be rotated by any suitable mechanism, j neferablj7 of such character that the speed of rotation of the shaft can be changed at will. rlhe furnace may, however, have a greater or less number of hearths than I have shown.

The shaft l() is preferably hollow so as to permit of the circulation of a cooling medium through it and it is surrounded bv relatively short sleeve sections llinterposed between the successive rotating hearths so as to aid in the support of the same, said sleeves being composed of fire brick, tile, or other heat-resisting material, in order to protect the shaft from injury by the high temperatures which may have to be maintained within the working chambers of the furnace. I

Speevcation of Letters Patent,

iPatenteol 2l?, fitti? 1.913, Serial No. 7,553,598.

rfhe outer wall of the furnace is composed of rings 12 ofl irebriclr, tile, or other refractory material made either in one piece or in sections and interposed between the successive fixed hearths of the furnace whereby'the building-up of a furnace structure having a closed casing can be elfected expeditiously and with small expenditure of ytime and labor..

ln order to restrict, as much as possible, the radiation of heat from the furnace, 'the outer wall-of the same is provided with a coating orcovering -13 of magnesia, asbestos cement, or'other material which is a nonconductor or a poor conductor of heat.

The. lowermost of the rotating hearths of the furnace is mounted upon a flange or collar 14 on the shaft 10, and, where said shaft passes through the top and bottom fined hearths, it is provided with luted joints l5 to prevent the escape of gas from the interior of the furnace at these points. rlhe top hearth of 'the furnace may conveniently be used as a, drying hearth, the material being fed inwardly over the same by means of rabbles l@ carried by rabble arms 17 secured to and projecting from the upper portion of the shaftlOr` the material being fed from the drying hearth 1, onto the first rotating hearth 2 througl'i the upper luted joint 15 and the course of the material in its pas sage through the furnace being then outwardly on the rotating hearths and inwardly on the stationary hearths, the rotating hearths being less in diameter than the interior of the furnace and the stationary hearths being provided with central openings i8 of greater diameter than the sleeves ll in order to permit of the `dropping of the materialfrom hearth to hearth. In order to provide for such n'ement of the material over the hearths rabliles are provided, these rabbles having stems supported in rabble holders which are mounted in openings in the fixed and rotating hearths and extend below the same so that the rabble stems can be readily applied thereto, the. rabbles of one hearth acting upon-tlie material on the hearth below. The hearths may be so constructed that the directioiifof travel of the material over the same will be the reverse of that just described Without departing j invention.

from any of the essential' features of my The rotating hearths are, by preference, composed of rings of tile or other refractory material, .either in one piece or in sections, and the stationary hearths may be composed of like rings. i

It is also advisable to provide the casing of the furnace at both the uppermost and lowermost chambers .thereof with a pipe or conduit for the introduction of air or the escape ofthe gases dcvelopedin the furnace, the use of such conduit at each end of the furnace providing for the operation of the latter with either updraft or downdraft.

When the rabbles are separate from the rabble holders, a rabble can be readily changed by withdrawing it horizontally from engagement with the rabble holder, removing it through a suitably located opening in the outer wall of the furnace, and inserting a fresh rabble in its place and the rabble holder', after the removal of the rabe ble, can be lifted from its seat in the hearth into the chamber above the hearth from vwhich it can likewise be withdrawn and a new one inserted in its place, whereas, if the rabble and rabble holder was made in one piece' this method of change could not be adopted and the furnace would have to be dismantled Whenever it became necessary to change the rabbles.

In a furnace of the type to which my invention relates. a great number of hearths can be used without unduly increasing the height of the furnace because said hearths can bevdisposed relatively close together, no

provision having to be made for the reception of rabble-Carrying arms in the cham bers between the hearths.

The rabble holders may project below the hearths, as shown for instance at Q0 and 20, Fig. l, so that the rabbles may be connected thereto by horizontally separable joints, as shownrespectively at 19 and 19, or the joints may be vertically separable as shown for instance at 19 and 20h, Fig. 1, or the rabbles may be applied directly to the hearth?,I in soule cases, as shown for instance at 19C, Fig. l, and the term depending from said hearths is intended to apply either to the construction in which the rabbles are applied directly to the hcarths or indirectly through the medium of the rabble holders.

The central shaft may be stationary and the outer casing rotatable if desired, or one may be rotated in one direction and the other in the opposite direction, but the construee tion which l have heretofore described is much to be preferred.

When vertically .separable couplings are einplojjcd bel we'en the rabbles a nd ral'ible holdersy or lwarths that portion of the rabble which enters the coupling is of lesser ver- -tical dimensions` than the distance between the' lbottom of the rabble and the hearth be-l neath so thatl the rabble may be first lowered to clear the coupling and then `Withdrzwm laterally from the chamber between the hearths, and the rabble holders S20a are less in depth than the distance between the adjoining hearths to permit of vertical separation from the hearth below and subsequent lateral removal from between said hearth and the hearth above.

l claim 1. A metallurgical furnace having a central shaft and an outer easing, one rotatable in respect to the other, overlapping hearths carried respectively by said central shaft and outer easing, and rabbles depending from said hearths and serving to move the material over the same.4 '4

2. A metallurgical furnace having a central shaft and an outer casing, one rotatable in respect to the other, hearths mounted alternately upon said central shaft and outer casing, and rings of refractory material surrounding said shaft and interposed between the hearths carried thereby so as to protect the shaft from heat and also aid in the support of the hearths..

3. A metallurgical furnace having alten nating fixed and rotating hearths, a central rotatable shaft on which said rotating hearths are mounted, and rings of refractory material surrounding said shaft and interposed. between the rotating hearths.

e. A metallurgical furnace provided with an outer casing and a central shaft, onerotatable in respect to the other, hearths projecting inwardly from said outer casing, and heart hs carried by and projecting outwardly from said central shaft and alternating with the other hearths, said outer casing being composed of rings of refractory material interposed between the hearths of said outer casing and serving to separate and support said hearths.

5. The combination, in a metallurgical furnace, of a series of supcrposed hearths acme of whichare rotatable in respect to the others, and rabble` depending from said hearths and separably coupled thereto, that portion of the rabble which enters the cou' p-ling being less in vertical dimensions than the distance between the bottom of the rabe ble and the hearth beneath.

G. rlhe combination., in a metallurgical furnace, of alternating fixed and rotating hearths, with rabbles depending from said hearths, and rabble holdersv mounted in said heartl'is so as to be vertically removable therefrom, said rabble holders being of less depth than the space between the hearth which carries them and the hearth above it and being in separable connection with the rabbles.

7. 'lhc cmnbination, in a metallurgical furnace of alternating fixed and rotating hearths, with rabbles depending from said hearths, and rabble holders mounted in said hearths so es o be vertically lemeyabe berefrom, said rabble holders being lees in depth than the space between the hearth. which oar l'es Vthem and the hearth above it, end the e abbles being so mounted in seid holders es to be horizontally separable therefrom.

n testimony Whereoi have signed my l name to 'this Specification, in the'presence of tw ,eubsemomg wltneeses.

UTL'EY WVDGE.

;messesi ,Yi/@TE A., "313mm, EMMIL'EON D., TURNER.