US1808951A - Boiler with superheater - Google Patents

Description

Filed Jan. 5, 1929 2 sheets sheet l J All INVENTOR 6 /442455 Goeoo/V ATTORNEY June 9,- 1931.

C. W. GORDON BOILER WITH SUPERHEAII'ER 2 Sheets-Sheet 2 Filed Jan. 5, 1929 IPIIII.

ooooo m ooooooooo oooooo O O O 0 OOOO Q-OOQOOOOOWOOOOO 7 um 6w IAVENTORE 6442455 14 GOBDON Patented June 9, 1931 UNITED STATES,

PATENT 'FFFICE.

oar-lanes w. eon-non, or rrnasnnrvrnnnnnw YORK, assrenoa TO THE HEATER comm-liar, or new Yonx, n. Y., A oo-arona'rron' or nnnnwnan BOILER VJITH SUPERHEATER Application filed January 5, 1929. Serial No. 330,438,

This invention relates to boilers with superheaters and particularly to that type of boilers commonly known as horizontal water tube and in which a plurality of water tubes i' are arranged in a generally horizontal direction.

' The principal object of the invention is to provide a new and improved construction for horizontal water tube boilers, having is superheatersby means of which higher superheat and increased rated capacity of the boiler may be secured.

According to the standard practice it is customary to construct such boilers with a plurality of banks ofwater tubes arranged at different distances from the furnace, and to employ a system of bafies extending transversely to the longitudinal axes of the water tubes, which bafiles define a plurality of gas passes through which the furnace gasesfiow in a tortuous path to the stack, each of the water tubes having a portion thereof located in each gas pass. The standard construction of the horizontal type of boiler has always been such thata considerable clearance or waste space is provided between the uppermost row of water tubes and the top of the boiler, in which space the superheater, until recently, has been almost exclusively located. In this location, the gas temperature was only sufficient for comparatively low superheat and although the superheat varied with the rating ofthe boiler, such variations were of little consequence because of the low final temperatures. As the demand for higher and higher superheat, that hasmarked advanced modern steam engineering practice, increased, it became necessary to change the location of iliesuperheater to bring the ele- 40 ments or units thereof, or at least a major portion of such units, within the first gas pass and nearer to the furnace. As it is also standard practice withboilers of this type to arrange the water tubes in staggered relationship, the insertion of the superheater units from the topof the boiler to extend vertically into the first gas pass in'the spaces between the water tubes presented the objec tion that it would necessitate an increase in the standard transverse spacing of the. tubes in order to provide sutlicientclearance between said tubes to accommodate the superheater elements and consequently not only would the width of the boiler be increased but the proper relative effective areas of the respective gas passes would be disturbed.

Although many other locations and arrangements of the superheater have been suggested for securing the desired higher degree of superheat, the expedient which has gone into most general use has beenthat known as the interdeck arrangement which consists in increasing the space between the first and second banks of water tubes and in placing of the superheater units to extend substantially horizontally within such spaces; this of course results in an increase in the height of the boiler. a V

The problem of meeting the ever increasing demands'for boilers of larger and'larger capacity, equipped with superheaters capable of delivering steam at higher andhigher temperatures,while at the same time keeping the overall boiler dimensions restricted within the limits of the space available for installation, has been one of the customary practice when a new power plant was designed to provide a boiler room of greater size than necessary to accommodate the number of boilers for the'initial requirement-s upon the plant, so that as the demands for power upon the plant increased additional boilers could be installed. When the time for making-the installation of the additional boilers arrived, it has usually been found that instead of merely adding additional boilers of the same rated capacity as those originally installed,the engineer was great difliculty. It has been met with a demand that the additional boilers be designed not only :for higher superheat v but also for a much greater rated capacity than the original boilers. The boiler room of the power plant having in most cases been designed to accommodate one or more additional boilers of the same rating as the'original boilers, it has been found extremely difficult to meet the demand that the additional boilers be of greater rating than those originallv provided. Therefore much attention has been given in recent yearsto the developing of various devices and expedients that would enable both boiler rating and the degree of superheat to be increased without necessitating a corresponding increase in the size of the boiler. As far as I'am aware, however, such expedients as have been heretofore suggested, have fallen far short of attaining the desired end. The present invention provides a means by which a much greater increase in boiler rating and superheatmay be secured without a corresponding increase in size than heretofore was thought possible.

The above and other objects of the present invention will appear more fully from the following more detailed description and by reference to the accompanying drawings forming a part hereof, wherein Fig. 1 is a somewhat diagrammatic longitudinal sectional view through a boiler constructed in accordance with the principles of the present invention and Fig. 2 is a transverse section through said boiler.

As shown in the drawings, the numeral 10 indicates the combustion chamber of a boiler and the numeral 11 the stack thereof. The boiler isprovided with the usual front and rear headers 12, 13 between which extend, in accordance with the usual practice, a plurality of water tubes, 14. These tubes, also in accordance with the standard practice, are arranged to form a plurality of banks 15, 16 and 17, the bank 15 consisting of one or more rows of tubes located nearest to the furnace,

the bank 16 consisting of a number ofrows of tubes spacedabove the bank 15, while the bank 17 consists of a still greater number of rows of tubes which in turn are spaced slightly above the bank 16.

In accordance with the standard construction heretofore employed for boilers ofthe type herein shown, each tube extends longitudinally of the boiler, that isfrom front. to rear, the rows of tubes of each bank extend transversely across the entire boiler from one side wall to the other side wall thereof and a system of transverse baffling is employed which causes the furnace gases to flow in a tortuous path from the combustion chamber to the stack. By transverse baffling is meant that'thc baffles are located in planes extending at right angles to the longitudinal center line of the boilerand reaching from one side wall of the boiler to the other side wall, the tubes passing through apertures provided in the baffles. As hereinbefore pointed out it was also the usual practice in such-boilers to lo cate the superheater within the space provided between banks 15 and 16, in which case the spacing of said banks is much greater than that shown in the drawings of this application. r

In accordance with the principles of the present invention, instead of employing the transverse baffling as is the standard practice,

a system of longitudinal baffling is employed. As shown in the drawings, a baflie 18 is provided which extends longitudinally of the boiler from the front header 12 to the rear header 13 immediately below the bank 16, the baflle lying in a substantially horizontal plane and parallel to the water tubes. This baffle extends transversely approximately half way across the boiler. Located substantially along the longitudinal center line of the boiler is a vertical bafiie 19, the top edge of which projects slightly above the top row of the tubes 14 and the bottom edge ofwhich is in contacting engagement with the inner ed e of the baiiie 18. The baffle 19 forms with tfie side wall 20 of the boiler the first pass 21 for the furnace gases. A third baffle 22 also extending vertically is-preferably located midway between the baflie 19 and the side wall 23 of the boiler, and has its bottom edge terminating a short distance above the top face of the bafile 18. The baffle 22, therefore, defines with the bafile 19 a second gas pass 24, and with the side wall 28 of the boiler, a third gas pass 25. For the purpose of insuring a substantially uniform flow of the gases from the first to the second gas passes, a fourth bafiie 26, also extending longitudinally of the boiler, projects downwardly from the top wall of the boiler and in alignment with the baffle 19, and the lower edge of said baffle 26 terminates as shown, above, and in parallelism with, the top of the bafile 19 thus providing a passageway 27 of uniform width from the front to the rear of the boiler between said first and second passes. The baffle 22 terminates at its upper end at the top wall of the boiler and is inclined, opposite to the passageway 27 so as to deflect downwardly into the second gas pass,'the gases which flow through said passageway. In order to provide sufficient space for the location of the superheater in the first, gas pass relatively close to the furnace and thereby secure a high degree of superheat,a number of rows of tubes are omitted between the first and third banks 15 and 17 respectively to provide a much larger interdeck space 28 than heretofore used, which space in the constructional rxam'ple shown is located, it will be noted, on one side of the boiler and entirely within the first gas pass.

As shown in the accompanying drawings the rows of tubes of the bank 16 instead of extending entirely across the boiler in accordance with the practice heretofore considered standard, are located solely to one side of the boiler and between the baffle 19 and the side wall 23 and said tubes are omitted entirely from the space between the bafiie 19 and the side wall 20. Extending into the space 28 from the side wall of the first gas pass is a plurality of superheater units 29 the ends of which extend through apertures in said side wall and are connected tov the inlet and outlet headers 31, 30, said headers as shown beinglocatedon the exterior of the boiler.

The section 32 of the side wall is preferably made removable so that the superheater units steam is led from the superheater outlet head er 30 by any suitable pipes or conduits to the place of use. It will be obvious that although the interdeck space 28 has been de scribed and shown as provided by the omission of all of the rows of tubes of the bank 16, in the first gas pass such space may be provided by omitting only a part of such rows or by omitting part of the rows of tubes of either or both of the banks 15 or 17, and that such omission may be either with or without an omission of tubes of the bank 16.

The exact location of the superheater, whether as shown with its units extending into the space ordinarily occupied by tubes of v the second bank or ata greater or lesser distance from the furnace will obviously be determined by the degree of superheat desired. It would not, for example, be a departure from the invention to omit the uppermost rows of tubes of the bank 17 and to locate the superheater in the upper part of the first gas pass.

Vith a boiler constructed in accordance with the principles of the invention herein disclosed, it will be seen that each respectve water tube has its entire length located entirely within a single gas pass instead of each tube, as with the standard transverse bafliing, having a portion thereof located within each gas pass. The total exposed surface area of water tubes in each gas pass may however, by a proper positioning of the baflles, be made the same as with the standard transverse baffling, as will be readily understood. The omission of the tubes between the baffle 19 and the side wall 20 permits of the provision of ample space for the interdeck superheater 29 and at the same time allows the space between the lowermost row of'tubes of the bank 17 and the row of tubes of the bank 15 to be very materially decreased. In fact by constructing a boiler in accordance with the principles of the present invention the amount of waste space is reduced by approximately As a result a boiler may be constructed in accordance with the principles of the present invention not only having the same rated capacity as a boiler employing the standard transverse battling but also obtaining greater superheat while at the same time obtaining a reduction in height of approximately 25%. Consequently where but a limitedspace is available and it is desired tubes in two banks to increase the rating of the boiler, a boiler of muchylarger rating and of highersuper heat may be installed by resorting to the principles herein disclosed yet avoiding the necessity of increasing the overall dnnensions of, the boiler.

In addition the provision of a clearance space in accordance with the principles of the invention possesses the marked advantage of permitting a superheater arrangement to be adopted, that not only is easier to install but also is more readily accessible for inspection, repair or replacement, as will be readily understood.

/Vhile a satisfactory constructional example embodying the principles of the present inventionhas been illustrated in the accompanying drawings, it will beunderstood that such example is merely illustrative of such principles and that the invention is not'limited to the specific constructional details shown, as many changes, variations and modifications of such details may be resorted-to without departing from the spirit of the invention. V

- For example, although the inventionhas been described and illustrated'for the purposeof the present disclosure as applied to a boiler in which the water tubes are arranged in three spaced banks and in which the superheater is located in spaces between the banks in what is known as in interdeck arrangement, it will be understood that as the arrangement of the Water tubes in three banks is resorted to for the purpose. of providing sufficient header capacity to insure proper circulation, the principles of the present invention which relate primarily to a system of bafiling, are not limited to the three bank arrangement described. It will therefore 'be understood that no departure from the present invention would be involved by arranging the instead of three banks as such "arrangement involves merely a matter of circulation. It will likewise be understood that no departure from the scope of the invention will be involved by omitting all of water tubes shown and I thermore, it will'be understood that the superheater elements could just as readily be vertically arranged with the headers located at the top of the boiler but with such headers preferably outside of the boiler walls.

Ineach of the. above cases the same system of longitudinal baffling would be employed and the sameprinciple resorted to of omitting in the first gas pass a number of rows of tubes sufficient to provide the desired space for the accommodation of the superheater units. Any of these arrangements that obviously may be resorted to will permit'the 2 rality of communicating first gas pass, ing vertically spaced from. each other above between saidfirst gas parallel to the planes of said 'locationof the superheater within the first gas pass relatively close to the furnace so that the desired'high degree of superheat may be obtained and at the same time will 1 enable a much larger number of water tubes to be installed in a boiler ofgiven dimensions than was possible with the system of battling heretofore considered standard.

I claim: 7

1.- In a horizontal water tube boiler,'a plurality of water tubes extending longitudinally of the boiler in inclined relation to the top thereof, a plurality of baflies extending longitudinally of said tubes to provide a plugas passes through which the furnace gases flow in a tortuous passage from the furnace to the stack, said baffle including a vertically extending pair which define with aside wall of the boiler a the members of said pair beto provide an opening pass and the second gas pass, said opening being of the same width throughout its entire length, and a transversely inclined baffle located in proximity to said opening for deflecting gases passing therethrough downwardly into said second gas pass.

2.- In a horizontal water tube boiler, .a plurality of water tubes extending longitudinally of the boiler ininclined relation to the top thereof, a plurality of bafiles extending the uppermost tubes longitudinally of said tubes to provide a plurality of communicating gas passes through which the furnace gases passage from the furnace to the stack,

flow in a tortuous said baflles including a vertically extending pair which defines with a side wall of the boiler a first gas pass, the members of said pair being vertically spaced from eachv other above the uppermost tubes to provide an opening between saidfirst gas pass and the second gas pass, said opening being of the same width throughout itsentire length, a plurality of superheater units extending into said first gas-pass and a plurality of water. tubes interposed'between said units and the boiler furnace.

3. In a boiler, a furnace ha "ng walls, and a plurality of groups of water tubes within said walls arranged in difler'ent substantially horizontal planes, a plurality of substantially vertical bafiies extending longitudinally of v ly of the those tubes only of one or more of said groups which are within said restricted portion being omitted to provide a clearance space, and a superheater arranged in said clearance space and having tubes arranged transversely of said Water tubes.

4. In a horizontal water tube boiler, a plurality of water tubes extending longitudinalboiler in inclined relation to the top thereof, a plurality of battles extending 1ongitudinally of said tubes to provide a plurality of communicating gas passes through which the furnace gases flow in a tortuous passage from the furnace to the stack, said baffles including a vertically extending pair which define with a side wall of the boiler a first gas pass, the members of said pair bemg vertically spaced from each other above the uppermost tubes to provide an opening between said first gas pass and the second gas pass, said opening being of the same width throughout itsentire length, and being inclined at an angle equal to the angle of inclination of' said tubes.

In testimony whereof I have hereunto set my hand.

CHARLES W. GORDON.

said tubes, a battle in a plane substantially groups and located above the lowest of said groups, said horizontal baflle extending from one of said vertical baffles transversely ofsaid tubes to one of the walls of the furnace, said bafiies providing a plurality of gas passes including a first gas pass having a relatively wide portion below'the plane of said horizontal battle and a relatively, restricted portion abovejthe plane of said horizontal bafile,

Images