US2042560A - Furnace wall - Google Patents

Description

June 2, 1936. A- H STEWART 2,042,560

FURNACE WALL I Filed Sept.y 28, 1954 2 Sheets-Sheet l l INVENTOR Patented June 2, 1936 UNITED STATES PATENT OFFICE FURNACE WALL Andrew H. Stewart, Shields, Pa. Application September 28, 1934, Serial No. 745,890

2 Claims.

My invention relates to furnace walls and more particularly to the walls of furnaces for molten glass or other metals;

In the case of glass-melting furnaces and the 5 like, the molten metal, particularly at what is known as the metal line or normal glass level, exerts a gradual progressive erosive action on the clay wall of the furnace. The furnace walls are usually constructed of what is known as tank l'y blocks, and as initially produced, have a somewhat smooth surface. The erosive action of the molten glass is not so rapid on a smooth surface as when the surface is rough or has become pitted and eroded.

Attempts have heretofore been made to '1ncrease the life of tank blocks by artificially cooling the same in order to retard the erosive effect of the molten glass. In some cases, air has been blown against the outer sidesof the blocks, 20 but if the block is made of sufficient thickness to render it suitable for use in a melting tank, the

cooling action of the air is not suiliciently effective, particularly when the block is new and is of its full thickness, because the heat transferred 25 through the block is approximately in direct inverse ratio to the thickness of the block.

One object of my invention is to provide for the cooling of the blocks at zones adjacent to their inner or glass-contacting surfaces.

Another object of my invention is to provide a structure wherein successively smooth surfaces are presented to the glass in the vicinity of the metal line, as the block is eroded or worn away.

Some of the forms which my invention may 35 take are shown in the accompanying drawings,

wherein Figure l is a sectional View, through a portion of a melting furnace embodying my invention; Fig. 2 is a similar View, but showing a portion of the block eroded or worn away by the 40 molten glass; Fig. 3 is a view taken on the line III- III of Fig. 1; Fig. 4 is an inner face View of one of the blocks; Fig. 5 is a plan View thereof; Fig. 6 is a view similar to Fig. l, but showing a modified form of block; Fig. 7 is a vertical sec- 45 tional view of the block of Fig. 6, but taken at right angles to the View of Fig. 6; Fig. 8 is a plan view of the block of Fig. 7, and Fig. 9 shows a manner in which the bridge wall of a furnace may be cooled.

Referring rst to Figs. l to 4, I show a furnace of somewhat the usual form, but employing specially-formed tank blocks I2 that extends somewhat above the normal glass level I3, and upon which tuck stones or blocks I4 are positioned as 55 is common in structures of this kind, the blocks I2 being replaceable without disturbing the structure above the tuck stones.

The blocks I2 may be cast or molded in any well-known manner, cores of wood or other suitable material being provided to produce the core 5' openings I5 and I6. The cores are preferably of wedge-like or tapered form, so that they can be readily removed from the block before it is fired. Lateral openings l1 and I8 extend from the outer surface of the block to the pocket-like core spaces l0 I5 and I6, respectively, the air pipes I9 and 20 discharging into the passageways I1 and I8, respectively, from an air supply line 2I, in which the pressure may be so low as to produce only a gentle flow of the air. l

The tuck stones I4 are preferably of channel form and provide a convenient exit for the cooling air that is blown through the pockets l5 and I6.

As is well understood in the art, the tendency of the glass to eat into or erode the blocks I2 is most pronounced at the metal line I3, and the effect on the block is shown more clearly in Fig.

2, wherein the inner wall has been dissolved or eaten away until the glass has entered the inner pockets I5. At this stage, the tuck stones I4 may be left in place or drawn backward somewhat on the supporting angles of the structural work, or replaced by other tuck stones that will overlie only the pockets I6, while molten 30 glass will enter into the recesses or openings I1, and freeze therein, as shown in Fig. 2.

The pockets I5 and I6 are of considerable width as shown more clearly in Figs. 4 and 5, so as to present wide smooth surfaces to the glass as the clay in front of the pockets is distintegrated. The pockets I6 are staggered relative to the pockets I5 so as to not necessarily weaken the block. As above-explained, the wide smooth surfaces of the pockets, when the molten glass has penetrated thus far into the block, are more resistant to erosive action than pitted or rough surfaces. When the molten glass has penetrated to the pockets I5, air is, of course, supplied only to the pockets I6, and after the glass has penetrated to the pockets I6, air can be blown against the outer surface of the block in the usual manner, the pipes I9 and 20 being suitable for this purpose also.

Referring now to Figs. 6, 'l .and 8, I show a 50 structure wherein pockets 25 and 26 which correspond somewhat to the pockets I5 and I6, are inclined relative to one another and communicate at their lower ends, as shown more clearly in Figs. 6 and 8. In this structure, discharge 55 pipes are required only for the pockets 25 since worn away to the pocket 33, the supply of air the air that is blown into such pockets will pass through the pipe 36 is cut off, and air is then out through the pockets 23 and beneath a plate supplied through the pipe 37. When the glass 21 that underlies the tuck stone. If desired, the has eaten into the pocket 34, the air supply 5 air could, of course, be blown through the pockets through the pipe 31 will be cut ofi", and air will 5 2G and then passed through the pockets 25, but then be directed through the pipe 38 to the rear it is preferable to have the air in a colder condiside of the block 32. tion supplied to the pockets 2E which are near- I` claim as my invention:- est the inner face of the block. When the glass l. A melting furnace having refractory walls has eaten into the pockets 25, the plate 27 will be provided with a series of slots adjacent to the 10 removed and the pipes 28 will be pulled back toinner surfaces of the walls and widened in didischarge directly to the pockets 26, and nally rections parallel to the planes of said surfaces, when the glass has eaten to the pockets 26, the vand 4also provided with recesses in staggered relapipes will be caused to discharge against the tion to the first-named recesses and located outermost face of the block. nearer to the outer surfaces of the side walls. l5

In Fig. 9, I show a fragmentary longitudinal 2. A melting furnace having a refractory wall sectional view of a furnace wherein the melting provided with a series of upwardly-exposed reend 30 is separated from the refining end 3| by a cesses at approximately the height of the molten bridge wall under which the molten yglass flows, metal level, and provided with a second series of as indicated by the arrows. The bridge wall is upwardly-exposed recesses between the rst- 20 provided with a block or blocks 32 at the side named series and the outer face of the wall, a

32 is provided with recesses or pockets 33-34 ing Huid through said recesses and channel j. which correspond to the pockets 25 and 25 of member, the channel member being supported for 25' Fig. 6. adjustment transversely of the furnace Wall The cover block 35 is recessed for the placing of whereby it may be caused to overlie only the air discharge pipes 36 and 3l that discharge into second-named series of recesses. the pockets 33 and 34. Air will rst be supplied 'through the pipe 36. After the block 32 has ANDREW H. STEWART. 30'

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