US2134000A - Wall construction - Google Patents

Description

Oct. 25, 1938. MAYO, 2,134,000

WALL CONSTRUCTION Filed NOV. 28, 1934 6 Sheets-Sheet 1 INVENTOR Dana HNMGJ/O B Oct. 25, 1938. D H. N A WALL CONSTRUCTION Filed Nov. 28, 1934 6 Sheets-Sheet 5 p r-w me T q "1' w w/z INVENTOR Dana HNMa /o v TTORNEY Oct. 25, 1938. DJ H. N. MAYO WALL CONSTRUCTION 6 Sheets-Sheet 4 Filed NOV. 28, 1954 4 1 I" ..l-". H .Ur -IF INVENTOR Dana HNMa z/0 Y Oct. 25, 1938. D. H. N. MAYO WALL CONSTRUCTION Filed Nov. 2 1954 e Sheets-Sheet 5' INVENTOR Oct. 25, 1938 D, H. N. MAYO WALL CONSTRUCTION Filed Nov. 28, 1934 6 Sheets-Sheet 6 Iln INVENTOR Dana HNM 0 ATORN Y I Patented Oct. 25, 1938 UNITED STATES WALL CONSTRUCTION Dana H. N. Mayo, Ridgewood, N. J., assignor to Ihe- Babcock & Wilcox Company, Newark, N. J., a corporation of New Jersey Application November 28', 1934, Serial No. 755,078

3 Claims. (Cl. 122235) This invention is concerned with wall constructions.

In a specific form it relates to improvements in apparatus through .which fluids or gases pass at different pressures and temperatures. It is exemplified herein as a steam boiler heated by furnace gases at pressures differing to an unusual degree in adjoining gas passes.

The invention will be readily understood from the description of the steam boiler shown in the accompanying drawings, in which:

Fig. 1 is a vertical sectional view of a Water tube steam boiler associated with a slag tap furnace.

Fig. 2 is a partial side elevation of the installation of Fig. 1, showing the exterior of the boiler casing and the position of the fluid cooled partition which extends through and completely separates two parts of the casing.

Fig. 3 is a View in the nature of a section taken on a horizontal plane at a level below that of the boiler drum.

Fig. 4 is a partial View in the nature of an elevation, showing the wall or casing construction at the juncture of the vertical and inclined parts of the fluid cooled partition.

Fig. 5 is a section on the line 5-5 of Fig. 4 showing the structure associating the vertical part of the fluid cooled partition with the high temperature casing on one side and. the low temperature casing on the other.

Fig. 6 is a section similar to that of Fig. 5, but taken on the section line 66 of Fig. 4, and showing the structure along the inclined part of the fluid cooled partition.

Fig. 7 is a View on the line 1'l of Fig. 8 in the nature of an end elevation of the downtake header side of the boiler, with the exterior casing removed.

Fig. 8 is a section taken on a plane indicated by the section line 8-8 of Fig. 7.

Fig. 9 is a partial side elevation indicating the relationship of the joint cooling tubes and the downtake headers of the steam generating section.

Fig. 10 is a section taken on the line IO-Hl of Fig. 9, and showing the fluid cooled expansion joint seal at a corner alongside the boiler downtake headers.

Fig. 11 is a partial side elevation indicating the construction at the boiler mud drum.

Fig. 12 is a section taken on the line l2-l2 of Fig. 11 and showing the corner seal at a level between the mud drum and the lower ends of the downtake headers.

Fig. 13 is a view in the nature of an elevation, showing the relationships of the parts near the tops of the downtake headers.

Fig. 14 is a view, partly in elevation and partly in vertical section, taken'on the line |4-l4 of the boiler.

Fig. 13, and looking in the direction of the arrows.

Fig. 15 is a partial section of a side wall. Referring to Fig. 1 of the drawings, there is shown a furnace from which hot gases pass across steam generating tubes and then through an up-pass 20. Under the effect of the induced draft fan 22 the gases are next drawn through the down-pass 24 and the outlet 26 to the air heater 28. They are drawn through the fan and blown through the exhaust conduit 30 to -a stack.

The gas pressures within the furnace and the gas passes are sub-atmospheric throughout, and the pressure at the outlet 26 is much less than the pressure at the bottom of the up-pass. It is also to be appreciated that these pressure relationships mustbe maintained if a uniformly high combustionrate is to be effected in the furnace and a uniformly high gas velocity secured in the gas passes. Any substantial gas leaks from the up-pass directly into the outlet or into the lower part of the down-pass would quickly impair the effectiveness of the apparatus because of the destructive action of the high temperature gases. Without said destructive action, such leakage would result in efliciency losses.

'The. gases in the up-pass have temperatures higher than those in the down-pass, and hundreds of degrees higher than the water, or water and steam mixture in the circulating system of Therefore, any physical parts of the apparatus which are separately affected by these different temperatures must be permited to have relative movement. This invention involves parts which cooperate to prevent the above described destructive action, but are so situated that they tend to separately approach the three different orders of temperatures mentioned. One ofthese parts is the casing section forming walls of the up-pass 20, and a second is the casing section forming walls of the down-pass 24. The third part is the fluid cooled partition 32 which separates the casing sections and is movable relative to them.

The manner in which the casing sections are related to the partition 32 is well illustrated in Fig. 6, of the drawings. This figure indicates a section through the junction of the casing sec-' tions with the partition wallwhich is protected on its up-pass side by cooling tubes 34 having'fins 36 welded thereto. These fins afford supports for the panels 38 and the interposed refractory 40. At the edges of the partition the refractory '42 is additionally held in position and protected by a welded fin 44 preferably disposed at a right angle to the fin 36.

The seal tube 46 is preferably made rigid with the partition by a Weld 48 secured to the panel construction or to a plate 49 rigid therewith. Baffle mix may be placed between this plate and the tube, and in all similar sealing positions. This tube also carries an expansion joint and gas seal structure including the angles 50, 52, 54 and 56 which are preferably rigid with a bar or fin 58 welded to the tube at 60. The angle 56 has one flange 62 welded to a fillet 64 which is in turn welded to the tube 46 and positioned parallel to the fin 58. Battle mix may be positioned between the tube 46 and theflange 62 as heat resisting material also acting as a filler.

One flange of the angle 50 is parallel to the flange 62 and spaced therefrom to provide a passage in which the flange 66 of the floating angle may slide with a reasonably close fit to prevent excessive leakage of air into the furnace. The other flange 68 of the floating angle is guided between an inclined buckstay I and a bar 12 fixed thereto. On the other side of the fin 58 there is a similar arrangement of elements cooperating with the floating angle 14.

The buckstay "I6 preferably supports a wall I8 which is a part of the casing section for the downpass 24, and the wall 80, a part of the up-pass casing section, which is thicker than the wall I8 because it is exposed to furnace gases at higher temperatures. The latter wall is guided by the buckstay I0, and an expansion joint gas seal is provided between the buckstay and the wall. As

shown, this seal consists of wall members forming channels 82 and 84 which slidably receive flanges 86 and 88 preferably secured, respectively. to. the buckstay I0 and the seal tube 46. The flange 88 is apart of a floating angle the other flange of which slides in a guideway formed by the'tube 46 and a' bar 90 spaced from the tube but welded to it along one edge.

Sealing strips or clips 92 secured to the floating angles 66 and complete the gas sealing structure. Asbestos packing may be placed under these strips and at all similar sealing positions. It will be noted that the parts rigid with the partition form therewith a complete wall extending between and. completely separating the confronting ends of the walls I8 and 80. The expansion joint gas seals are separate and are located on opposite sides of the partition. With this arrangement of elements, gas leaks direct from the up-pass 20 to the lower pressure downpass 24 are prevented. In the event that a leak occurs the gas movement will be from the atmosphereinto the furnace and the wall parts will not be subject to the destructive action of high temperature gases.

Fig. of the drawings illustrates the manner in which the vertical section of the partition is associated with the separate casing sections. It is similar to disclosure of Fig. 4 and will be readily understood to be a continuation of the Fig. 4 structure. The wall 93 is in a somewhat lower temperature gas zone than the wall 80, and hence is not as thick.

Fig. 4 illustrates the junction of the vertical buckstays H0 and H2 with the inclined buckstays I0 and 16. These parts, as well as the expansion joint parts between them, are shown as being mitered so as to form a single straight line joint, butit is to be understood that separate mitered sections of these parts might be added to the joint so as to make it a two-line joint. In this latter event the juncture of the buckstays and their attached parts would approach the curvature of the seal tube 46 which is shown as having a gradual curvature at the juncture of the vertical and inclined portions of the partition 32.

The partition cooling tubes 34 are connected into the boiler circulation as indicated in Fig. 2.

They, are directly connected at their lower ends to the downtake headers H4, while the seal tubes 46 extend downwardly along the sides of the end headers and are connected at their lower ends The drum and the circulators are shown suspended from the framework I24 by loops I26 and rods I28.

In the up-pass and the down-pass separated by the partition tubes 34 banks of fluid heat exchange tubes are shown. The cooler gases in the down-pass contact with the tubes of the economizer I30. These tubes are connected to an inlet header which receives feed water from any convenient source. At their other ends they are connected to the water space of the drum I20 through the intermediacy of the outlet header I34.

In the up-pass there are located two fluid heaters I36 and I38. These heaters may be superheaters connected in series-or in parallel, or one of them may be a reheater. The tubes of these heaters are shown extending through the exterior wall I40 of the up-pass 20 to inlet headers I42 and I44 on one side, and to outlet headers I46 and I48 on the other side. All of these head ers are preferably in vertical alignment and are supported by the saturated steam tubes I50 and I52 arranged in rows on opposite sides of the header. These tubes are shown to be supported by suspension rods I54 and I56 from the framework I24. They are connected at their lower ends to the header I42 and at their upper ends to the steam space of the drum I20.

The downtake headers I I4 are connected to the water space of the drum I20 by downtake circulators I58 as shown in Figs. 1 and. 15 of the drawings. These circulators are preferably positioned in two spaced rows where they cross the outlet 26. With this arrangement there is no excessive flow resistance imposed upon the gases by the downtake circulators. Along their upper parts they support refractory material which forms the rearward wall I60 of the down-pass 24.

As shown particularly in Figs. '7 and 8, the end downtake header is joined to the seal tube at intervals. This juncture is effected by flns I 62 and I64 which are welded together in overlapping relationship as indicated more particularly in Fig. 8. Fig. also shows this structure in detail. Here, the seal tube 46 has metallic studs I66 welded thereto in radial positions and embedded in refractory material I68 exposed to the furnace gases at the juncture of the wall 80 and the wall formed by the inside surfaces of the downtake header.

Oppositethe fin I64 there is shown the expansion joint fin I10. The latter is preferably welded to the tube 46 and is positioned to have a sliding fit within a passage I12 formed by the buckstay I14 and the angle I'I6. This arrangement of elements permits the pressure parts, including the seal tubes and the downtake headers, to move relative to the casing sections and the buckstays, without excessive leakage of gases from the furnace.

Fig. 7 shows the mud drum extending out beyond the end headers I I4 for connection with the seal tubes 46 and a blow-off connection I80. Inwardly of these connections the mud drum is joined with the separate headers II4 by nipples II8 which are preferably expanded into fluid tight relationship therewith.

As shown in Fig. 12 the nipples I18 have flanges I82 welded thereto at opposite sides. These fianges overlap flanges I83 welded to the seal tubes, and similar elements are provided throughout the length of the mud drum to complete a wall which may maintain refractory material similar to that shown at I68.

Fig. 12 also shows the angles I84 and I86 between which the fillet I88 may be welded to form a closed passage receiving the fin I10 with a sliding fit and gas sealing relationship. These angles are fixed to a slotted buckstay I90 which appears in both of Figs. 10 and 12.

The downtake headers are connected to the uptake headers I92 by horizontally inclined steam generating tubes I93 which extend across the path of hot gases passing from the furnace I96. The latter is indicated as a slag tap furnace fired by burners I88 and 200 supplied with secondary air through the chamber 202. These burners preferably direct fuel streams between wall tubes 206 connected at their ends to headers 208 and 2I0. Similar wall tubes 209 join the headers 208 and 2I2 on one side of the furnace, and 2 I4 and 2I6 on the other side of the furnace. The water tubes are preferably covered with refractory as are the floor tubes 2I8. When a slag pool collects in the furnace it may be tapped through the opening 220.

The headers 2I0 and 2I6 are connected into the boiler circulation by tubes 222 and 224 and there may be similar tubes connecting the lower headers with the drum I20. Similar connections 226 and 228 are provided for the headers 230 and 232 of a furnace screen formed by inclined tubes 234 connecting the headers 230 and 232.

The hot gases from the furnace pass through the flue or outlet 26 to a dust hopper 240 located at the base of the air heater 28. Any material collecting in this hopper may be withdrawn through the discharge tube 242.

Referring to Fig. 3 of the drawings the partition 32 is shown between the front and rear walls I40 and I60. Beyond the wall I40 is an exterior casing having the panel wall 244, and a similar exterior casing wall 246 is shown spaced from the wall I60. Fig. 2 shows a .side wall connecting the walls 244 and 246. It includes the buckstays I I0 and H2 and other vertical members 248 and 250 of an outside insulating panel wall construction as well as the horizontals 252, 254 and 256.

In the structure indicated in Fig. 2 of the drawings the exterior wall is preferably of insulating panel construction and the wall sections A B C D E, and F G H H I J K are unitarily suspended from the load carrying structure at the top of the installation. These sections thus expand downwardly, as do the pressure parts of the boiler. Along the line K H H there is preferably located an expansion joint, permitting this expansion and the upward expansion of the panel wall section L M O P R which is preferably supported by the water tube side wall of the furnace.

In Fig. 15 of the drawings the horizontal structural members 252 and 254 are shown. Between these members there is positioned a bottom supported wall consisting of a metal panel section 256 and refractory material 258. This wall is preferably supported upon the wall tubes 260 which are connected to the header 262. Extending upwardly from the position of the member 252 is a part of the top supporting wall, including a panel construction 264 and refractory 266. At the junction of these two Walls the upper part 268 of the lower wall is shown as overlapping a refractory footing 210. These parts are placed and arranged as shown in order that the bottom supporting wall may expand freely in an upward direction.

What is claimed is:

1. In a water tube steam boiler, a horizontally inclined bank of steam generating tubes, uptake and downtake header constructions at oppositetake header construction, a cross header forming a mud drum extending transversely below the downtake header construction and extended beyond the sides of said construction, means establishing direct communication between the cross header and the downtake header construction, and tubes extending along the edges of said wall and connected to the ends of the cross headers extended beyond said construction, said latter tubes being also otherwise connected into the boiler circulation.

2. In a water tube steam boiler, a steam and water drum, a bank of inclined steam generating tubes, uptake and downtake headers at opposite ends of said bank of tubes, means connecting said headers to the drum, an angled baille positioned above said bank of tubes so as to separate two gas passes and including parallel water tubes extending from thetops of the downtake headers toward the opposite side of the boiler and then upwardly, said baffle including seal tubes having their upper portions parallel to said water tubes and their lower portions extending alongside the downtake headers beyond the lower end of the baflle, means connecting said water tubes to the drum, means closing the spaces between the parallel water tubes and said additional tubes, and a mud drum positioned below the lower ends of the downtake headers and connected to them, the seal tubes having their lower ends connected to the ends of the mud drum.

7 3. In a fluid heat exchange system, upright sectional headers at one side of a gas pass, sectional side walls defining opposite sides of the gas pass, a convection section including a bank of tubes connected to headers and extending across the gas pass, a baffle wall extendingupwardly above an intermediate portion of the tubes of said bank and laterally outwardly beyond the inner surfaces of said side walls, spaced wall cooling tubes communicating with said headers and defining said baflle wall, side seal tubes parallel to wall tubes and positioned at the vertical margins of the baffle wall, said seal tubes extending into spaces between confronting and adjacent sections of the side walls and extending downwardly alongside the outermost of said headers, means connecting the convection section and the seal tubes into the fluid circulation of the system, and refractory means closing the spaces between said wall tubes and between the wall tubes and the seal tubes.

DANA H. N. MAYO.

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