US2704999A - Fluid cooled enclosure providing access ports - Google Patents

Description

G. J. scHoEssow 2,704,999

FLUID coouan ENCLOSURE PROVIDING ACCESS PORTS 2 Sheets-Sheet l N$ N g INVENTOR G/ezz J Jc/zoessow i M a mm mm w L NMW m m m L w W m A \i N m KN \I w m b wm OM [I'll m m 3 RL m mi 0mm I m I '1 a M M m Q R c w ||||1 a Q (L March 29, 1955 Filed July 8, 1948 ATTORNEY March 29, 1955 G. J. SCHOESSOW 2,704,999

FLUID COOLED ENCLOSURE PROVIDING ACCESS PORTS Filed July 8, 1948 2 Sheets-Sheet 2 INVENTOR ATTORNEY United States Patent Ofiice 2,704,999 Patented Mar. 29, 1955 FLUID COOLED ENCLOSURE PROVIDING ACCESS PORTS Glen J. Schoessow, Barber-ton, Ohio, assignor to The Babcock & Wilcox Company, New York, N. Y., a corporation of New Jersey Application July 8, 1948, Serial No. 37,642

7 Claims. (Cl. 122-65) The present invention relates in general to a fluid cooled enclosure providing ports through which interior chamber conditions may be observed and interior wall surfaces rendered accessible for inspection and cleaning.

ln boiler construction, for example, wherein the outer enclosing walls are generally upright and rectangularly arranged, it has been customary to provide wall ports or openings in the planar side or end wall areas for the purpose of observing interior furnace conditions, or for removing slag accumulations from the various interior surfaces by means of a lance or other implement inserted through the opening. Each port is, of course, fitted with a suitable closure means and, when provided in a planar wall area, generally results in an assembly which appreciably limits the angle of vision and also the available working range through any one port. It has therefore been necessary to provide a considerable number of such ports in each of the surrounding walls in order to permit observation of the chamber throughout at least the greater part of its cross section, and to render interior wall surfaces accessible for observation and cleaning through the various ports. In certain boiler constructions, the formation of ports in planar wall areas is often dependent on the design and support of the unit which might require their relocation in less advantageous positions.

An important feature of my invention relates to the formation of an inspection port or access opening at the corner formed between two intersecting walls whereby the angle of vision is substantially increased and conditions within the chamber may be observed throughout its entire cross section. Similarly, the available working range is increased and lancing of adjoining wall areas may be readily accomplished. This is particularly desirable in heat exchange apparatus having fluid cooled walls defining a combustion chamber in view of the necessity of maintaining the exposed inner wall surfaces clear of excess slag accumulations for increased efficiency of heat transfer.

Another object of my invention relates to the formation of an inspection and lance port between wall tubes normally in contact or otherwise affording a width of intertube space less than the width of access .opening required.

An additional object relates to the formation of an access opening between closely spaced tubes associated with adjoining walls, and to provide a suitable closure means for such an opening.

A further object of my invention relates to the support of a wall port closure means on tubes associated with adjoining wall areas, and to the maintenance of such tubes in relatively fixed relation adjacent the sides of the port whereby the closure means may be rigidly attached to the tubes without risk of damage to its component ports.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described a preferred embodiment of my invention.

Of the drawings:

Fig. 1 is an exterior front elevational view of a boiler unit embodying a fluid cooled enclosure constructed in accordance with my invention;

Fig. 2 is a plan view of the unit shown in Fig. 1, partly in section along line 22;

Fig. 3 is a fragmentary exterior elevational view of Fig. l, rotated through 45, showing the formation of a corner port and indicating the closure means therefor;

Fig. 4 1s, a sectional plan view, taken along line 4-4 of Fig. 3 showing further details of the corner construction;

l igc.1 5 is a side view of the structure shown in Fig. 3; an

Fig. 6 is a fragmentary sectional plan view of Fig. 1, taken along line 6-6, for example, directly above one of the wall-supporting buckstay units, with the outer casing omitted.

in more detail, Figs. 1 and 2 illustrate an embodiment of my invention in a known type of vapor generating unit 10 having a setting of substantially horizontal cross section as defined by upright front and rear walls 12 and 13, respectively, together with oppositely disposed upright side walls 14 and 15. The space within the setting includes a combustion chamber or space 17 lying at one side of an upright fluid cooled wall, herein indicated by dotted line 18, by which the combustion chamber is partitioned from a boiler tube space 19 at the opposite side. One or more burners 21 of a type suitable for the fuel to be burned are installed in the front furnace wall 12, for example, to provide a source of heating gases. Air for combustion is delivered to the burners by means including a wind box 23 and an air supply duct 24.

The partition wall 18 terminates short of the rear furnace wall 13 to provide a passage 25 through which heating gases are discharged from combustion chamber 17. The gases entering the tube space 19 are caused to flow horizontally, across a bank of boiler tubes 26 in a plurality of passes defined by cross baflies 27 and 28, and are finally discharged through gas outlet 29.

In this form of boiler unit, all walls surrounding the combustion chamber are fluid cooled as provided, for example, by tubes 2, 3, and 5, in exterior upright walls 12, 13, and 15, respectively, and also by tubes 8 in the interior upright partition wall 18. The lateral boundary of the chamber is completed by tubes 30 which are arranged in one or more rows across the gas flow passage 25 to provide a screen in advance of tubular heating surface in tube space 19.

It may be assumed, 'without requiring specific illustration, that the entire weight of the unit including walls 12, 13, 14, and 15 is top-supported, with the weight transferred to the customary structural framework. It is to be understood however that in certain instances, depending on the particular arrangement of parts, for example, a unit of this general type may desirably derive its vertical support from below, as disclosed in my copending patent application Serial No. 654,239, filed March 14, 1946, now Patent No. 2,583,599. In either case, the vertical support of all walls is made from a common elevation along the various Wall tube lengths, whereby the tubes in each two adjoining walls move in unison in response to expansion and contraction so as to obviate relative vertical movement of one wall with respect to another, particularly at the corners of the setting.

In addition to the customary vertical support provided for each upright wall of the unit from a predetermined elevation, it will be noted that the walls 12, 13, 14, and 15 are afforded lateral support at several elevations by means of horizontally extending buckstay units 31, 32, and 34, each of which is constructed substantially as shown for similar units in the aforesaid copending application. Accordingly, one buckstay unit, namely unit 31, encompasses all four upright walls of boiler unit 10, while a second buckstay unit 32, associated only with Walls 12, 13, and 15, is secured at its inner end to the lower boiler drum 35. An additional unit 34, which may be tied-in to the structure of wind box 23, is associated with the four upright walls 12, 13, 15, and 36 which define the lower extended portion of combustion chamber 17, at elevations below muddrum 35, the buckstay unit 34 being located preferably below burner level and above the converging hopper portion 37.

As indicated in Fig. l, inspection doors 38 are desirably arranged at different elevations, and at each elevation, preferably at an outer corner of combustion chamber 17 from which location a view of the entire cross section of the chamber may be had through a single port 39 when the door is open. However, in order that all portions of the chamber may be viewed at reasonably close range, and from different directions, and the cleaning of the various wall surfaces facilitated, the ports 39 are preferably formed at both outer corners of chamber 17, as indicated in Fig. 2. For a unit of the type shown, it will be understood that, except for a region including a port 39, the wall tubes 2, 3, and are arranged vertically and in parallel relationship throughout the major portions of their lengths and are closely spaced in their respective rows adjacent the inner face of the heat insulating refractory material 40.

The ports 39 and doors 38 are thus associated with corners which are defined by walls in which the tubes are closely spaced, and since similar close spacing of tubes is maintained across each outer corner, there is normally no intertube space provided of a width corresponding to the width of inspection or lance port required. In side wall 15, for example, which is the common defining wall for both outer corners, the tubes 5, with the exception of the terminal tubes 5a at opposite ends, are arranged at center-to-center spacings equal to the tube diameters so as to place successive tubes in contact substantially throughout the row. As will be noted from Fig. 6, each end tube 5a is displaced at an angle of approximately 26 /2 from the planar arrangement of the remaining tubes 5 of the row so as to occupy a position midway between, and in planar alignment with, a next to the last tube 5b of the tube row 5 and an end tube 2a or 3a of the rows of tubes associated respectively with front wall 12 and rear wall 13. The end tubes 2a, 2b and 5a, 5b of the respective rows in adjoining walls 12 and thus constitute a series of upright wall tubes arranged in closely spaced succession across the front outer corner of chamber 17, while the end tubes 3a, 3b and 5a, 5b of the respective rows in adjoining walls 13 and 15 constitute a similar series of upright wall tubes arranged in closely spaced succession across the rear outer corner of chamber 17.

Fig. 6 also illustrates the arrangement of buckstay unit 32 at and adjacent outer corners of the combustion chamber as formed between side wall 15 and the front and rear walls 12 and 13. Buckstay units 31 and 34 at other elevations are of the same general arrangement,

and in each case, unit 31, 32, or 34 may be considered as being of essentially the same construction as a simi' larly positioned buckstay unit disclosed in said prior application. Each buckstay unit therefore includes a tie bar 41 in each of the front and rear walls 12 and 13, and a tie bar 42 in side wall 15, with the tie bars secured to tubes 2, 3 and 5 in their respective rows, and meeting at the corners 43 where they are rigidly con nected, as by welding. Buckstays 45 and 46 for the respective walls are secured at intervals therealong to the corresponding tie bars by tie plates 47 and 48 and, for adjoining walls, are interconnected at each outer corner by a horizontally disposed gusset plate 49 welded to the adjacent tie bars 41 and 43. Slotted bolt holes are provided in the tie plates and gusset plates to permit longitudinal movement of each tube-lined wall 12, 13, or 15 relative to the corresponding buckstay, as more fully described in the aforesaid prior application.

As indicated in Fig. 4, each row of wall tubes terminates in spaced relation to the inner surface of the adjoining wall, at right angles thereto. Accordingly, the end tube 2a in wall 12 is spaced at a distance of one tube diameter from the inner surface of wall 15, and the end tube 5a in wall 15 is spaced at a distance of one tube diameter from the inner surface of wall 12. Thus, a plane tangent to the transversely aligned tubes 5 at one side is also tangent to the end tube 2a at the opposite side of the plane. Similarly, the end tube 511 in wall 15, and the transversely aligned tubes 2, in wall 12, are disposed at opposite sides of a common tangential plane parallel to wall 12. It will be noted that in wall 15, the end tube 5a is arranged at the same center-to-center spacing from the next adjacent tube 5b as for transversely aligned tubes 5 of the row, and that its displacement from the centerline of the row is one-half of its diameter,

thereby placing the centerline of tube 5a in the first above mentioned common tangential plane, parallel to wall 15.

With wall tubes arranged as described, a corner port 39 may be formed by locally displacing intermediate portions of one or more tubes of each of the adjoining walls, at and adjacent the desired port location, thereby repositioning certain tube portions so as to define a port of predetermined width, and other tube portions so as to provide suitable support for the port closure means as hereinafter explained. In the illustrative embodiment, the local displacement of intermediate tube portions is effected by reverse bends which are formed to radii considerably greater than the tube diameters and which serve to restore the various tube length portions to their normal positions at elevations above and below the port. As indicated in Figs. 3, 4, and 5, for wall 12, the end tube 2a, and the next adjacent tube 2b, are reversely bent in planes at right angles to each other, thereby displacing a portion of the tube 2b to the position 2b outwardly of its original position of planar alignment with other tubes 2. The displacement of tube portion 212 is at right angles to the plane of the row of tubes 2, and the extent of displacement, at least one tube diameter. The end tube 2a is formed with reverse bends in the plane of the row of tubes 2 and its intermediate portion 2a moved to the space made available by the displacement of the tube length portion 2b. The tube length 2a is thus in axial alignment midway of its length with the undisplaced straight length portions of the next adjacent tube 212.

The two end tubes in the adjoining wall 15 are similarly formed with reverse bends and their intermediate portions similarly displaced. Thus, in wall 15, the next to the last end tube 5b of the row is provided with an intermediate portion 5b which is displaced a distance of at least one tube diameter to a position outwardly of the row of tubes 5, with the displacement being eifected in a plane at right angles to the row. The terminal tube 5:: is reversely bent in a plane inclined to the plane of the row of tubes 5 and containing the centerlines of tubes 5a and 511. Thus, tube 5a is provided with an intermediate portion 5a which occupies a portion of the space made available by the displacement of the tube portion 5b, in which position the tube portion 5a is in axial alignment midway of its length with straight, undisplaced portions of tube 512, and thereby in transverse alignment with the row of tubes 5.

As herein illustrated, the closure means for a wall port 39 comprises a door 52 having a pivotal connection with a door frame 53 whereby the door is arranged for horizontal swinging movement about a vertical axis as provided by hinge pin 56 which extends through lugs 57 and 58 on the door and the frame respectively. A door-latching mechanism is provided which includes a pivoted latch 59 on the door, and a stationary catch 61 on the frame.

The door frame 53 is formed with an inner flange 62 which defines a rectangular frame opening 63 symmetrically arranged with respect to the port 39, the flange 62 having vertically disposed side portions 64 of enlarged cross section toward their inner ends and presenting arcuate surfaces 65 in contact with the outwardly displaced wall tube portions 2b and 5b at opposite sides of the port. The frame 53 is secured to the wall by means of studs 67 having their inner ends threaded into socket members 68 which are welded to the tube portions 2b and 5b, and having their outer ends threaded to receive clamping nuts 69. The outwardly displaced tube portions 2b and 5b are preferably maintained straight and vertical, parallel to undisplaced tubes of the respective rows, throughout the height of the frame opening 63, and continuing above and below the opening, thereby affording a wide entrance to port 39 and providing a right cylindrical surface suitable for the assembly of door frame 53 thereto. A rim of packing 71 surrounds the opening 63 and provides a door seat surface 72 in a plane parallel to the straight length tube portions 2b and 5b to which the frame is secured. The wall casing 73 is suitably secured to marginal portions of the frame by means of bolts 74. It will be noted that the frame flange portions 64 have their inner sides inclined to the plane of the door seat surface 72 at an angle suitably greater than 45 and are disposed to the outside of converging planes A-A which are tangent,

respectively, to the port-defining tube portions 2a and 2b, and 5a and 5b, at opposite sides. The planes A-A, and the tube portions to which they are tangent, are arranged at right angles to each other and thus are parallel to adjoining walls at the corner so as to afford a line of vision throughout the extent of each wall.

The door assembly 52 includes a layer of high temperature block insulation 75 together with door lining tile 76, suitably in two sections and extending inwardly to about the centerlines of the door-supporting tubular elements 2b and 5b, the tile insert 76 being engaged by a frame-like tile retainer 78 having inwardly converging wall portions as indicated in Figs. 4 and 5, and held in position thereby through the medium of studs 79 which are received in lugs 81 on the tile retainer and extend through the wall of the door. The tile insert 76 and the tile retainer 78 are each formed with inclined peripheral walls, and particularly with inwardly converging side walls 82 which conform substantially to the inclination of the converging tangential planes A-A. This formation of the tile insert and tile retainer permits the installation of a thick layer of refractory material which practically fills the flared entrance to the port when the door is closed, and which obviates any restriction of the available sight or working angle when the door is open.

The arrangement described provides numerous features which are particularly advantageous in the design, construction, and maintenance of heat exchange apparatus. These advantages stern largely from the novel arrangement of each port at a corner of the enclosed chamber, whereby one door thus located provides better and more complete observation than has heertofore been possible with a plurality of doors variously positioned in planar wall areas. In the design of a vapor generating unit, for example, where a considerable area of the front furnace wall is covered by a burner box and associated air ducts, there is often a scarcity of room for a door of adequate size in the remaining planar area of the same wall, whereas a door may readily be positioned at the adjacent corner because of the smaller planar wall area required and the fact that the total required area is distributed over the corner portions of two walls. Moreover, a door located at the corner of a furnace is' in a cooler location than a planar furnace wall area. From an operating standpoint, it is a great improvement to provide a single corner port through which the entire cross section of a chamber may be observed, instead of having to provide a plurality of ports at other locations for the same purpose, thereby enabling the operator to make all required observations by opening only one door,

and as a result, increasing the operator performance and efficiency.

While in accordance with the provisions of the statutes I have illustrated and described herein the best form of my invention now known to me, those skilled in the art will understand that changes may be made in the form of the apparatus disclosed without departing from the spirit of the invention covered by my claims, and that certain features of my invention may sometimes be used to advantage without a corresponding use of other features.

I claim:

1. In a fluid heater having upright walls defining a heating chamber of horizontal polygonal cross section, said walls having fluid heating tubes associated therewith including a series of said tubes arranged upright across a corner formed between two of said walls, and means forming a port at said corner affording a view of said chamber substantially throughout said cross section, said port having upright side wall portions diverging outwardly from said chamber and each portion being disposed substantially parallel to the adjoining chamber wall which is at the opposite side of said port, said side wall portions respectively comprising a pair of contiguously arranged interior and exterior tubes of said series each having an intermediate portion horizontally offset in the form of a single plane bend throughout the height of said opening, said exterior tube of said pair having its offset portion extending toward the outer side of said series of tubes and said interior tube of said pair having its offset portion extending to the space vacated by the single plane bend of said exterior tube.

2. A furnace enclosure comprising upright fluid cooled walls meeting at a corner and supported from a common elevation so as to obviate movement of one wall relative to the other at said corner as a result of wall temperature variations, said walls having upright fluid heating tubes associated therewith and comprising a series of said tubes arranged across said corner, means defining an opening in said furnace enclosure comprising an exterior tube of said series at each side of said corner and opening having an intermediate portion offset outwardly with respect to said furnace enclosure, and a pair of interior tubes of said series each respectively contiguous to one of said exterior tubes and having an intermediate portion oifset laterally into the space vacated by the outwardly oifset portion of the adjacent exterior tube, tie bar means tying together successive tubes of each of said walls including some of said tubes having portions defining said opening, means rigidly interconnecting said tie bar means for the respective walls at said corner, a door frame secured to certain of said offset tube portions defining opposite sides of said opening, and a door for said opening mounted on said frame.

3. In a fluid heater having upright walls meeting at a corner, said walls having upright fluid heating tubes associated therewith including a series of said tubes arranged in successive relationship across said corner, and means defining an opening at said corner of greater width that the total intertube space afforded between tubes of said series, said means comprising a pair of contiguously arranged interior and exterior tubes of said series at one side of said opening having intermediate portions offset respectively in intersecting planes at a common elevation, said interior tube having its offset length portion disposed at the intersection of said planes in axial alignment with the major length portion of said exterior tube.

4. An enclosure comprising upright walls meeting at a corner and having upright tubes arranged in rows extending along said walls and continuing into said corner, and means defining an opening at said corner comprising an intermediate tube of each of said rows having a portion offset outwardly from its row in a plane extending transversely of its row, and a terminal tube of each row contiguous to said intermediate tube and having a portion offset in a plane intersecting said first named plane, said offset portion of said terminal tube extending to the spgce vacated by the offset portion of said intermediate tu e. I

5. An enclosure comprising upright walls meeting at a corner and having upright tubes arranged in rows extending along said walls and continuing into said corner, and means defining an opening at said corner comprising an intermediate tube of each of said rows having a portion at a common level oflset outwardly from its row in a respective upright plane extending transversely of its row, and a terminal tube of each one of said rows in contiguous relation to the said intermediate tube of its row and having a portion offset longitudinally of its row into a position in said respective upright plane inwardly adjacent said first named offset tube portion.

6. An enclosure comprising upright walls meeting at a corner and having upright tubes arranged in rows extending along the respective walls and continuing into said corner, and means defining an opening at said corner comprising an intermediate tube of each of said rows having an intermediate portion at a common level offset outwardly from its row in a respective upright plane extending transversely of its row, and a terminal tube of each row contiguous to the respective intermediate tube of its row and having an intermediate portion offset longitudinally of its row into a position in said respective upright plane inwardly adjacent said first named offset tube portion, means tying together successive tubes of said rows adjacent said corner, a door frame rigidly secured to said outwardly offset tube portions, and a door for said opening mounted on said frame.

7. In heat exchange apparatus having a heating chamber of horizontal polygonal cross section, upright fluid cooled walls defining said chamber comprising fluid heating tubes associated with said walls and including a series of said tubes arranged upright across a corner of said chamber, and means defining an opening at said corner affording a view of said chamber substantially throughout said cross section, said opening being formed between separate but adjacent groups of tubes of said series and having upright side walls of which each side wall of said opening is defined by horizontally displaced portions of the nearest and innermost pair of tubes of a separate one of said groups, said displaced tube portions at each side of said opening lying tangent to a plane ex tending parallel to the chamber wall which is at the opposite side of said opening, said plane being at a location inglardly spaced from said chamber wall at said opposite 51 e.

323,882 Pratt Aug. 4, 1885 Lapp Sept. 17, Liptak Wells May 18, Bailey Mar. 12, Lucke Nov. 26, Millar Dec. 24, Bennett Mar. 22, Jackson Oct. 18, Van Brunt et al May 20, Kruger June 3, Artsay Aug. 3,

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