US2045661A - Door for metallurgical furnaces - Google Patents

Description

June 30, 1936. 1 s`- LoN'GENEcKER 2,@45663 DOOR FOR METLLURGICAL FURNACES Filed Jem.- 22, 1934 2 Sheets-Shet l 7 17 m s 51a! 311i L J L JLL g Y// uw INVENTOR 51M wm M2 www June 30, 1936. Y 1 s; LONGII-:NCKER O 2,045,561 1 DOOR FOR METALLURGICAL FURNACES Filed Jn. 22, 1954 2 Sheets-Sheet 2 Patented June 30, 1936 piro spares ATENT OFFICE Doon Foa METALLURGICAL FURNACES Levi S. Longenecker, Pittsburgh, Pa. Application January 22, 1934, serial No. 707,678

a claims. .(ol. 11o- 173) This invention relates to metallurgical furnaces, and more particularly to charging doors therefor.

An object of this invention is the provision of an improved type of charging door for metallurgical furnaces.

Another object of the invention is the provision of a. charging door for metallurgical furnaces that shall be capable of withstanding high furnace temperatures, and that shall be simple in construction and relatively easy to manufacture.

A further object of the invention is the provision of a charging door having a refractory lining which is rigidly supported as a unit in a frame and that may be easily removed from the frame for repairs and replacements.

Other objects of the invention will, in part, be apparent and will, in part, be obvious from the following description taken in conjunction with the accompanying drawings, in which:

Figure l is a. fragmentary View, partly in section, of a metallurgical furnace having a charging opening in the front wall thereof and provided with vertically movable doors, one of Which is shown in vertical section, and embodying one form of the invention;

Fig. 2 is a view in front elevation of a door frame for the furnace shown in Fig. 1, to which' the refractory door lining is attached, the door frame being of the air cooled type;

Fig. 3 is a view in perspective of a refractory block and a hanger employed in the lining of the furnace door;

Fig. 3a. is a View similar to Fig. 3 showing the tongued side of the refractory block used in the door lining;

Fig. 3b is a view in perspective of the hanger shown with the block shown in Figs. 3 and 3a;

Fig. 4 is a view partlyY inV end elevation and partly in section taken on line IV-IV of Fig. 5 of the door frame shown in Figs. 5 and 7;

Fig. 5 is a view in rear elevation of the door frame shown in Fig. 3;

Fig. 6 is a fragmentary enlarged view in section, taken on line VI-VI of Fig. 5, of the Water cooled door frame showing a hanger for a block of the refractory lining mounted in interlocking relation to the frame;

Fig. 7 is a top plan view of a series of door frames, such as shown in Figs. 3 and 5, mountedV in the position they would occupy when in operative relation to the charging door opening of the furnace shown in Fig. 1 (one of these doors being shown in full width and partly in section, the

doors on opposite sides thereof being fragmentary, and one in section) Fig. 8 is a fragmentary view in rear elevation of the door frame shown in Fig. 2, on which two rows or courses. of blocks of the refractory 1ining have been laid up; and

Fig. 9 is a fragmentary view in rear elevation of a door such as shown in Figs. 3 to 7, inclusive, on which three rows or courses of blocks of the refractory lining have been laid up, the blocks of the lining being made up of single and double Width to effect an interlocking of the various courses.

Throughout the drawings and the specification, like reference characters indicate like parts.

In my copending application Serial No. 707,677, filed January 22, I1934, a metallurgical furnace is shown which embodies` front and rear walls, a suspended roof, and a charging door opening in the front wall which is continuous and substantially uninterrupted throughout the full length of the charging chamber of the furnace. The charging doors herein illustrated `are designed primarily for use in connection with furnaces of the type disclosed in my above-mentioned copending application, andare arranged for tandem mounting lengthwisev of the furnace to thereby provide a door arrangement which affords the operator the opportunity of uncovering the charging door opening throughout its full length, or to open or uncover only a portion of such charging opening at any selected or desired point.

In Fig. 1 of the drawings a fragment of the furnace illustrated in my copending application is shown and designated by reference character l. The front wall and the charging door opening of this furnace are designated by reference characters 2 and 3, respectively.

The suspended roof for this furnace comprises a plurality of courses of refractory blocks or bricks 4 and 4 which are suspended by means of hangers 5 from beamv 6 that extend transversely of the furnace across thegtop thereof and which are supported Aat the front of the furnace by a beam 7 that runs longitudinally of the furnace and above its front wall. The ends of these beams 6 extending to the furnace back wall (not shown) are likewise supported on a beam or appropriate support member such as is disclosed in my above-mentioned copending application.

The charging door opening 2 may be covered or uncovered by means of a series of doors 8 disposed in tandem relation longitudinally of the furnace in the manner indicated in Fig. 7, and

these ldoors may be independently mounted for vertical movement, as disclosed in my aforementioned copending application, so that they may be raised or lowered in unison, or one or more at a time as the occasion requires.

The doors for this charging opening may be of the air cooled type or of the water cooled type and in either type a refractory lining 9 composed of refractory blocks or bricks I9 is employed, which alone is exposed to the temperature of the heating or charging chamber of the furnace. Whether these doors are of the air cooled or water cooled type, the refractory lining is attached to a frame which may be either water cooled or air cooled, the attachment to the'frame being of such character that the lining cannot fall away from the frame into the furnace even though the blocks or bricks of the lining may burn away almost completely in service.

In a preferred form of the invention as embodied inthese doors it is preferred to utilize the type of refractory blocks or bricks shown in my U. S. Patents No. 1,590,303, granted June 29, 1926 and No. 1,913,168, granted June 6, 1933. In the latter patent, modified forms of the refractory blocks or bricks of my earlier patent are shown, the modification thereof being such as to adapt them vfor use with individual support hangers in the construction of suspended roofs or walis. Hangers for this purpose are also shown and described in connection with the apron wall illustrated `in my United States Patent No. 1,977,799 granted October 23, 1934.

In Figs. 1 and 2 of the drawings, the air cooled. type of door is 'illustrated'and comprises a frame II having open sides, a back I2 of skeleton-like formation, and top and bottom plates lI3 and I4 which extend inwardly from the back and at substantially right angles thereto. The top plate I3 is provided with pairs of lugs I5 located adjacent the opposite ends of the top plate to which a bale I 6 may be attached for use in suspending the door from an operating cable I'I. The operating cable, it will be understood, is employed to raise and lower the door as the occasion requires. To guide the doors and maintain them in vertical position as they are raised or lowered, lugs L may be `provided to cooperate with a guide cable C. This feature is shown in my above-.mentioned application.

The back I-21of the door frame consists of a plurality of 'vertical .risers I8 `in which relatively narrow slots I9 are formed. The upper end of each of these slots terminates in a relatively wide slot portion VZIJ lthrough which means are inserted for anchoring the refractory lining of the door to the back of the door frame. These vertical `risers or uprights I8 may be connected lby horizontal vertically spaced ribs orstruts 2l for rigidifying and bracing the door frame.V To protect plate I4 from wear, a wear plate W may be secured thereto, and this plate rests on the threshold yplate of the furnace.

In order to rigidify and strengthen the top plate I3, a plurality of gussets 22 spaced lengthwise of the door are provided which tie the top plate to the back of the door frame.

The lining 9 for the door comprises a plurality of courses 23 of refractory blocks or bricks I9 each of 'which is formed with T shaped grooves 24 (as in the roof blocks) in one face near the outer end thereof for the reception of a hanger or retainer 25 having a leg 26 of T shape. Each .hanger embodies also a relatively short leg 21 which rests in a recess in the opposite face of the block to which it is attached. Thus, when a hanger 25 is attached to a block, the T shaped leg and the relatively short leg thereof are in effect concealed or imbedded in the block. The outer end of each hanger is formed with a pair of transverse lugs 28 and these lugs are of such width as to span a slot I9 in the door frame when mounted in the position shown in Fig. 1.

When a hanger 25 is attached to a block, the block and hanger are raised as a unit under the top plate I3, alined with the enlarged slot portion 20 of a slot I9, and then moved towards the back of the door frame until the lugs 28 of the hanger or retainer pass through the same. By lowering the block and hanger, the legs 26 and 2 of the hanger move downwardly through the slot while the .lugs 28 thereof span the slot and prevent the hanger and block from being pulled away from the back of the door frame.

By attaching hangers to a block in this fashion and attaching them to the `back of the door frame in the manner above described, the courses of blocks may be laid up until the complete lining is assembled.

The preferred type of refractory block for a door of this character is, as stated previously herein, disclosed in my above-mentioned patents. The blocks therein and herein disclosed are each provided with a triangularly shaped tongue 39a'I on one face like tongues 30 and 35 in blocks 4 and 4 and a triangularly shaped recess or groove Sla in the opposite face that occupies substantially the same position-and'location as the tongue. By laying the refractory blocks up in courses, the tongue of one block `rests in a correspondingly shaped recess in a block disposed below the same so that the joint between continguous faces of these blocks is completely s-ealed, whereby the back of the door frame is protected from direct radiation of heat from the furnace and from burning gases. These tongues and grooves also protect the hangers which tie the blocks to the door frame, from radiant heat and leakage gas flames.

As may be seen in Fig. 1, the refractory blocks I0 are laid up course upon course, with the triangularly shaped grooves or recesses 3Ia facing upwards until the lining is built up Vto a height slightly below the tops of slots I9, this height being indicated at `A in Fig. l. When this height is reached, the blocks are reversed and laid with the tongues facing upwardly. At the point where the reversal occurs, modified blocks may be used, that is, blocks having vplane instead of grooved faces or blocks having recesses filled up with cement so as to present flat contacting surfaces as indicated at line A. Thus, all of the blocks in the courses, including the last course, within the top of slots I9 are anchored by hangers to the door frame. The blocks I0 in the courses above slots I9 are of course tied to the courses below them by the interlocking tongues and grooves thereof and are therefore indirectly tied to the back of the door frame. As indicated in Fig. l, only the two uppermost courses of blocks are thus indirectly tied to the door frame.

In Fig. 8, two courses of refractory blocks I 9 are shown laid up on a door frame I I. As there illustrated the joints between the blocks of the various courses are not broken, but in practice the contacting edges of the blocks may have a, coating of cement applied thereto to seal the joints between them.

n Fig. 9 three courses of refractory blocks are shown laid upon the door frame shown in Figs. 3 to "I, inclusive. The blocks of these courses are of modied construction so that the same may be laid up with broken joints. The modified blocks lll herein illustrated are of double Width Whereas the blocks l employed in the door of Fig. 7 are of single width. The double width blocks are provided on one face with two triangularly shaped tongues 30a which are so spaced as to occupy the same location as the tongues of a single Awidth block, and the opposite faces are provided with two triangularly shaped grooves or recesses 3io which occupy substantially the same position and location as the tongues in the opposite face. The outer ends of these blocks may also be formed to accommodate two hangers 25 so that each double width block may be anchored in two slots in the door frame. In laying up the courses of a lining utilizing the double width type of block, a single width block I0 may be placed at one end of the bottom plate followed by the` necessary number of double width blocks and if the length of the bottom plate is not such as willbe equal to a completed course of double width blocks a single width block may be placed at the other end of the bottom plate. The next course of blocks as shown in Fig. 9 is composed of double Width blocks. The tongues of these blocks nest in the triangularly shaped grooves or recesses in the blocks in the course below. The next course of refractory blocks is like the` rst course. Thus, when the refractory lining is laid up in accordance with Fig. 9, every other row will consist of double width blocks which interlock with courses composed of single and double width blocks.

With the type of lining shown in Fig. 9, the joints between the various courses are broken so that at no place in the lining is there a joint of any appreciable length through which gas flames or radiant energy may penetrate. These joints being short they may be completely sealed with suitable cement. Since the blocks in the various courses are interlocked as above described, the sides of the door which are defined by the edges of the refractory blocks will remain plumb and true and cannot be displaced in service.

This is also true with the type of lining indicated in Fig. 8 because the hangers are attached rigidly to the blocks, and by reason of the fact that the rear ends of the blocks lie close to the back of the door frame, the blocks at the edges or sides of the door cannot separate or move out of line to any appreciable or undesirable extent.

The linings shown in Figs. 8 and 9 may be used with either type of door frame illustrated herein.

The water cooled door frame shown in Figs. 3 to 7, inclusive, comprises a pair of spaced inner and outer plates 33 and 34 that constitute the back of the frame. The upper edges of these plates are flanged inwardly as at 35 and 3S, the ends of which flanges are connected by a closure plate 3l.

The inner plate 33, as may be seen in Figs. 3, 5, and '7, is longer than the outer plate and the vertical edges of the outer plate are flanged inwardly as at 38 and 39 and welded to the inner plate.

The lower edges of the inner and outer plates are anged inwardly in the same fashion as at the top of the door, to provide a hollow fluid-tight shelf 40 upon which the lowermost course of bricks or blocks rest.

' In order to provide means with 'whichfthe transverse lugs 28 of the hangers 25 may interlock to hold the refractory lining in place, the inner plate 33 of each door is provided with spaced vertical slots 4| which terminate at their upper ends in relatively wide slot portions 42 through which the transverse lugs of the hangers or retainers 25 are inserted in the process of laying up the refractory lining. In order to seal these slots from the interior chamber of the door frame, channels 43 are placed over slots 4l-42 and Welded to the inside face of the plate 33, the line of weld of the channel to such plate being such as to completely close off communication with the door frame chamber and the slots.

When a door frame is thus constructed, the frame is hollow and fluid tight so that water or other cooling liquid may be circulated through the same. To provide for the circulation of water through the door, inlet and outlets 45 and 46 are provided at the top of the door to which iexible pipes (not shown) may be connected to convey the liquid through the chamber of the door frame. At the bottom of the door, drain plugs 41 are provided so that the door may be drained when necessary. To rigidify and stiifen the door, staybolts or stayrivets 45 may be employed.

When a door has been construction in accordance with the drawings, the joint between the vertical edges of the inner door plates may be effectively sealed by means of a plate 4!) secured to an edge of one door, so as to overlap the joint between adjacent edges of two doors and rest on the edge of the adjacent door (see Fig. '7).

When a water cooled door is constructed as above described, it will be observed that the inwardly extending flanges at the top and bottom of the door plates 33 and 34 perform in effect the same function as the top and bottom plates I3 and I4 of the air cooled doors shown in Figs. 1 and 3.

The bottom flange of the door may be protected from wear by means of wear plate 55 that is secured to the door frame in any suitable manner. When the door is closed, the wear plate rests on the threshold plate I of a furnace.

The water or liquid cooled door may be suspended in the same fashion as described in connection with the air cooled door and in order to provide for its suspension from an operating cable, the top of each door is provided with a pair of spaced lugs 52 and 53 to which a bail disclosed in connection with the door of Figs. 1 and 2 may be attached.

While but two forms of door have been shown and described as embodying the invention, it will be appreciated by those skilled in this art that various modifications and changes may be made without departing from the spirit or scope of the invention. It is desired, therefore, that only such limitations shall be placed on the invention as are imposed by the prior art and the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. A charging door for metallurgical furnaces comprising a metallic frame having a back, and inwardly projecting top and bottom plates disposed at substantially right angles to and integral with the back, said back having a plurality of spaced relatively narrow vertical slots terminating in relatively wide slot portions at the tops thereof, a brick lining for the inner face of the door and supported on said bottom plate, and hangers attached to the bricks of said lining, said hangers having extensions projecting through said slots and provided with lugs wider than the narrow portions of the slots in said frame for holding the bricks in place, said lugs being inserted through the wide portions of the slots in the back of the door frame in the assembly of said lining and means attached to said top plate for raising and lowering the door.

2. A charging door for metallurgical furnaces comprising a metallic frame having a back, and inwardly projecting top and bottom plates disposed at substantially right angles to and integral with the back, said back including spaced walls to denne a water chamber, and having a plurality of relatively narrow vertical slots terminating in relatively Wide slot portions at the tops thereof, a brick lining for the inner face of the door and supported on said bottom plate, and hangers attached to the bricks of said 1ining, said hangers having extensions extending through said slots and provided with lugs wider than the narrow portions .ofsaidfslots forlholding the bricks in place, v*said :lugs bei-ng inserted through the wide portions of k.the slots in the assembly of said lining, and means attached to said top plate for raising and lowering the door.

3. A lcharging door V:for metallurgical furnaces comprising a lmetallic frame having a back, and inwardly projecting top and bottom plates disposed at substantially right angles to .and `integral with the back, said back including spaced walls to define a water chamber, the inner of said walls having a plurality of vertical slots terminating in relatively wide slot portions at the tops thereof and channel members overlying the slots to separate the water chamber therefrom, a brick lining for the inner face of the -door and supported on said bottom plate, and hangers attached to the bricks -of said lining, said hangers having extensionsextending through said slots and provide-dwith lugs Wider ,than the narrow portions of said slots for holding the bricks in place, said lugs being inserted through the wide portions of the slots in the assembly of said lining, and means attached to said top plate for raising and lowering the door.

LEVI S. LONGENECKER.

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