US1898428A - Water tube steam boiler - Google Patents

Description

Feb. 21, 1933'. DINGER 1,898,428

WATER TUBE STEAM BOILER Filed May 9, 1930 2 Sheets-Sheet 1 3 nnen tor dttorncgs'.

Feb. 21, 1933. H, D N Q; 1,898,428

WATER TUBE STEAM BOILER Filed May 9, 1930 2 Sheets-Sheet 2 8 Smaentor wr (F21! e.

attorney-S.

Patented Feb. 21, 1933 UNITED STATES PATENT? OF F ICE- warm rune strum BOILER Application filed May 8,1980. Serial No. 451,075.

peculiarly associated in a furnace casing as to utilize the heat of the furnace proportionately to that required for the efiicient r operation of the respective sections, and wherein the high pressure section traverses the zone of highest temperature and wherein thelow pressure section, utilizing the waste heat from the zone of the high pressure section, is efliciently operated without the independent or separate generation of heat and without detractlng from the efficiency in the heating of the high pressure section.

- The present invention also aims at the provision of a novel water tube steam boiler wherein bent tubes are provided for taking care of normal expansion and are so arranged that they may be expanded in the drums and headers by the usual method employed and wherein the tubes are located more nearly a vertical position than is permissible in boilers of this type, wherein a superheater is employed peculiarly positioned between upper and lower banks of tubes so that access may be readily had to the superheater,

and wherein certain of the tubes are so pos tioned and bent as to lie in the back wall of the furnace and promote a natural circulation of Water and generated steam throughout the high pressure section of the boiler.

A still further object of the invention is to provide a water tube steam boiler with upper drums or headers peculiarly connected to series of downcomer and return tubes as to promote a relatively fast circulation of water and steam.

The present invention also embodies certain detail improvements and arrangements which will be hereafter more partlcularly described and brought out and which may be used, interchanged or discarded according to the character of the installation and the particular use to which the steam boiler is to be put.

With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto. 00

In the drawings, wherein like symbols refer to like or corresponding parts throughout the several views,

Figure 1 is a vertical longitudinal section taken through a water tube steam boiler constricted according to the present invention, an 7 Figure 2 is a front elevation of the same with the furnace structure removed.

Referring to the drawings, and first to Figure 1, there is shown a furnace of one configuration and construction, and it is to be. understood that this however is only for the purpose of illustration and that the furnace structure may be varied or modified to meet various conditions of installation and use. 7 In the present example, the furnace is provided with a front wall 10 having a burner opening 11 through which may be mounted v a burner of any suitable type, and the furnace is provided with a rear wall 12 which extends upwardly and into a top wall 13 extending forwardly of the furnace and terminating in a suitable stack 14 located substantially over the front wall 10. The top wall is continued forwardly of the stack 14 to provide a top forwardly and downwardly inclined section 15 which meets w1th the I and the stack 14 so as to utilize the waste heat from the high pressure section before the heat is exhausted through the stack.

The low pressure section comprises an upper drum 17 which is arranged behind the stack 14 and disposed through the top 13 of the furnace with the lower water receiving portion of the drum 17 projecting into the furnace and the upper steam receiving portion of the drum 17 lying above the top 13. A feed pi e 18 opens through one end of the drum 1 below the normal surface level of the water of the drum for introducing raw water into the drum, the pipe 18 being arranged toward the forward side of the drum and between the same and a baffle plate 19 which extends upwardly from said side of the drum at a point below the pipe 18.

The baffle 19 forms a water inlet chamber at the forward side of the drum which is separated from the remaining water space in the lower portion of the drum. The drum 17 is provided with a group of downcomer tubes 20 which are suitably connected in substantially radial relation to the drum and which open from said feed water space, and which are curved and extend downwardly V at an inclination to the vertical in spaced relation beneath the forward front top section 15 of the furnace, and which open into a front header 21 mounted in the front of the furnace.

The header 21 is connected to a second group or bank of pipes 22 ,which preferably correspond in number to the pipes 20 and which serve as return pipes and extend upwardly beneath the pipe 20, are curved and are headed in the lower wall of the drum 17 beneath the partition 19. The front header 21 is provided at a low point with a suitable blow-off cock 23 for removing sediment or other accumulations settling in the bottom of the header 21.

The drum 17 is provided with another group or bank of downcomer pipes 24 which are expanded in the bottom of the drum 17 adjacent to the pipes 22, and which extend downwardly beneath and preferably in spaced relation to the pipes 22 and open into a second lower header 25. A second set of return pipes 26 lead upwardly from the lower portion of the header 25 to the drum 17 and are suitably connected thereto at its under side. A dry pipe 27 leads from the upper portion of the drum 17 to carry off steam accumulating in the top of the drum, the steam being adapted to be delivered at approximately from 50 to 200 pounds pressure. The second front header 25 is also provided with a blow-off cock 28 for removing sediment and other accumulations from the bottom of the header.

The high pressure section of the boiler is located beneath the low pressure section and comprises a drum or upper header 29 which is preferably of larger diameter than the drum 17 and which is provided with a feed pipe 30 adapted to receive filtered water or condensate. The pipe 30 enters through one end of the drum 29 along the front wall thereof below the normal surface level of the water in the drum and the space about the pipe 30 is segregated from the remainder of the water space in the drum by a partition plate 31 which rises from the lower front wall of the drum to a point above the normal surface level of the water.

This water receiving space between the partition 31 and the drum is in communication with a bank of downcomer tubes 32 which are expanded or otherwise suitably headed in the front wall of the drum 29, which are suitably curved, and which extend downwardly in spaced relation beneath the tubes 26 of the low pressure section, and which terminate in the upper portion of a header 33 also mounted in the inclined section 16 of the front wall of the furnace. The lower portion of the header 33 communicates with return pipes 34 which lead upwardly to and are secured through the lower front wall of the drum 29 beneath the partition 31. The drum 29 is also provided with a bank of curved circulation tubes 35 which are connected to the lower wall of the drum 29 adjacent the tubes 34 and which extend forwardly and downwardly beneath said tubes 34 to a front header 36 mounted in the front wall of the furnace.

The header 36 is in communication with i the lower ends of a bank of return pipes 37 which extend upwardly, are curved and are expanded into the lower rear wall of the drum 29. The front headers 33 and 36 are each provided with a blow-off cock 38 by means of which sediment and other accumulations in the bottoms of the headers may be removed.

successively disposed in rotation and opening into the rear lower wall of the drum 29 is a bank or group of downcomer tubes 39 which are suitably curved and extend downwardly and forwardly to a front header 40 mounted upon the top of the front wall 10 and which at their upper ends open into the drum 29 at points beneath the normal surface level of the water in the drum. Return pipes 41 lead from the lower portion of the header 40 upwardly beneath the tubes 39 and open into the rear wall of the drum 29 at a point above the normal surface level of the water in the drum.

' A; deflector or bafiie plate 42 is carried upon the upper rear wall of the drum 29 and extends downwardly and forwardly therefrom to a point beneath the normal level surface of the water in the drum for deflecting water and steam'downwardly and out of direct contact with a dry pipe 43 which leads from the upper part of the drum 29 and is adapted to conduct the steam under high pressure, such as'at 250 or more pounds to the superheater.

Abottom header 44 is arranged across the tower end of the rear wall 12 and may extend along the opposite sides of the furnace and isconnected at its forward ends by pipes 45 to the lower header 40 seated on top of the front wall 10, the pipe 45 being of relatively large diameter as compared with the tubes above described for freely admitting of the down flow of water and steam from the header 40 into the bottom header 44. The header 40 is also in direct communication with the 35 header 36 by one or more pipes 46 which preferably have interposed in them force pumps 47 for increasingthe circulation through the system and through the bottom header 44.

The rear transverse portion of the bottom '39 header 44 is connected by vertically disposed tubes 48 to the rear side of the drum 29, and

as shown in Figure 1, certain of these tubes 48 are connected above the normal surface level of the water in the drum 29 and other of the tubes open into the drum below the normal surface level of the water.

By this means there is a natural circulation through the tubes 48 and header 44 when the pumps 47 are not in operation.

The side portions or wings of the lower header 44 mayalso be connected to the drum 29 by a plurality of vertical tubes 49 which extend from the header 44 to the lower and rear walls of the drum 29 as clearly shown,

in Figure 1. It is of course understood that these pipes 49 are arranged at both sides of the furnace and may be used in any desired number, or may be completely eliminated as desired. v

A superheater 50, of the hair-pin type and provided with headers 51 and 52 is mounted in the lower part of the boiler, preferably between the banks of tubes 37 and 39 and with the heads 50 and 51 mounted in the inclined v portion 16 of-the front wall of the furnace the lower header 52 of the superheater through a pipe for consumption as shown in Figure 2. Of course the number of tubes in the superheater 50 may be varied from three to six or more, and the superheater may or may not be used according to the requirements, and the superheater may be modified in construction and design to suit any special conditions.

In operation, the products of combustion generated in the lower end of the furnace will rise upwardly about the various tubes of first the high pressure section and finally about the tubes of the low pressure section before the products of combustion are carried off through a stack 14. The cold raw water entering the pipe 18 flows through the downcomer tubes 20 into the head 21 and thence upwardly through the return tubes 22 into the lower end of the low pressure header or drum 17 at the outer side of the bafie 19. This preliminarily heated water then flows in the drum 17 to the downcomer tubes 24 which carry the Water to the second head 25 from which the water rises in circulation through the return tubes 26 into the water section of thedrum 17. The steam accumulating in the tubes is liberated through the water in the drum 17 and rises to the top thereof and is carried off in the dry pipe 27 for consumption.

As to the high pressure section of the steam boiler, the feed water, properly conditioned, enters through the pipe 30 into the top drum 29 behind the baffle plate 31 and. passes down the outer rows of tubes 32 to the header 33 Whichois the uppermost of the high pressure front drums. From the drum 33 the water is carried in circulation up through the adjacent rows of tubes 34and into the. top drum 29 outside of the partition 31 The water then passes down through the next adjacent row "of tubes '35 into the second lower drum 36, and thence upwardly therefrom through the rows of tubes 37 back to the lower rear the water from the second drum 36v passes through the do wncomer pipes 46 to the lower water drum or header 40, and from whence a portion of the water passes'to the bottom or back header 44 through the pipes 45, and thence to the steam space at the rear portion of theupper drum 29 beneath the bafile 42 through the tubes 48.

Where the side tubes 49 are used a certain amount of this water will pass upwardly through the tubes 49 into various portions of the lower section of the drum; 29. From the header 40 there will also be an independent circulation between this header and the top drum 29 through the pipes 39 and 41, the

two rows 4lnext to the fire or source of heat discharge above the water line inthe. top

drum 29, thus securing a relatively dry steam.

The steam generated in the various tubes is collected in the top of the drum orheader 29 and carried outwardly through the dry pipe 48 and steam pipe 53 to the superheater 50, and is thence conducted through the pipe 54 to the desired point of use.

By this system there is created a natural path of circulation of the water, causing a natural and continuous flow of water from the coldest to the hottest part and a countercirculation of the gases from the hotter tubes to the colder tubes. The steam bubbles rise and are liberated at the water level. The hottest tubes next to the fire will discharge their mixture of steam and water above the water level.

The abrupt changes in direction of the water will have a tendency to throw out sediment and have it collect at the bottom of the various water drums, from which it can be blown or drained.

This is an important feature, which tends to trap the sediment before it can reach the hottest tubes. This will, therefore, tend to prevent burning out of tubes due to deposits from foreign matter coming in with the feed water.

Due to the positive and rapid circulation established, it is believed that the heating surface of this boiler will be very effective, allowing for higher rates of evaporation than are usually experienced.

By installing pumps 47, of preferably the propeller type, in the downcolner pipes 46 a forced circulation may be established for the water in the tubes connected to the headers 4A, 40 and 36, which will cause a more rapid flow of water through the tubes connected to these headers, causing greater heat transfer and also guarding against burning out of these tubes at high rates.

This forced circulation in these tubes will also indirectly cause a more rapid circulation in the other tubes, which act as downcomers.

This boiler can be operated with or without this forced circulation device. The accidental stopping of any of the pumps will not cause damage, but merely a less rapid circulation. This is, therefore, not a forced circulation boiler, but a boiler with a device for causing increased circulation at will to the hotter tubes connected to their headers.

This forced circulation would not be used except when it was desired to operate at very high rates, or as a measure of protection when impure water was contained in the boiler. This forced circulation would tend to arrest the formation of scale.

The radiant heat tubes l8 in the back wall, are arranged so that the row next to the fire discharges into thesteam drum 29 above the water line, while the other row passes between the two first rows of inclined tubes to level. This back row, therefore, may serve as downcomers for the water, but steam formed in these tubes has ready access to the steam drum.

This arrangement may serve to cause a circulation under natural conditions down the back row and up the fire row, which discharges above the water level. When forced circulation is on, both of these ttbes will be up-comers. A positive flow of water through these tubes is, therefore, ensured.

The headers shown may be seamless forgings or headers built up by welding, fitted with hand hole plates for access to the tube ends.

It is obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claims:

What is claimed is 1. An improved water tube steam boiler, comprising a furnace, high and low pressure sections mounted in the furnace with an upper drum for each section, said drums arranged at the top of the furnace, a plurality of lower headers for each section, banks of downcomer and return tubes disposed between veach drum and its respective set of lower headers for connecting the lower headers and banks of tubes in independent series between the respective drums of the sections, and means for independently collecting the steam generated in the independent high and low pressure sections from the upper parts of said drums.

2. An improved water tube steam boiler, comprising a furnace, a pair of drums mounted in the upper portion of the furnace, a series of front headers for each drum arranged in the lower front portion of the furnace, indepedent banks of downcomer and return tubes arranged in groups between the respective drums and the headers of each series for effecting independent circulation of water between the drums and their respective series of headers, and means for independently drawing off the accumulating steam from the tops of the drums.

3. An improved water tube steam boiler, comprising a furnace, a drum at the top of the furnace, lower headers in the front of the furnace, a bottom header in the rear of the furnace, independent banks of downcomer and return pipes arranged between the drum and the bottom and lower headers, downcomer pipes interconnecting the lowermost front headers, a connecting pipe leading from one of the lowermost headers to the bottom header, and optionally operable means arranged in said downcomer pipes for forcing the circulation through said tubes and headers.

4. A11 improved water tube steam boiler, comprising a furnace, an upper drum in the furnace, a plurality of lower headers at the front of the furnace, a bottom header at the rear of the furnace, a set of downcomer and return tubes between the drum and each header, a downcomer pipe interconnecting the lowermost headers at the front of the furnace, a pipe connecting the lowermost header at the front of the furnace to the bottom header at the rear of the furnace, and means mounted in the downcomer pipe for forcing a circulation through said lowermost and bottom headers,

HENRY CHARLES DINGER.

Images