US1883294A - Series boiler with superheater between boiler tubes - Google Patents

Description

Oct. 18, 1932. D. s. JACOBUS 1,883,294

SERIES BOILER WITH SUPERHEATER BETWEEN BOILER TUBES 5 Sheets-Sheet Original Filed April 16 191.8

\ lNV NTOR BY g wfiwq ATTORNEYG D DUUUU umnmumum mmm 06L 18,1932. [1 5, JACQBUS 1,883,294

SERIESL-BOILER WITH SUPERHEATER BETWEEN-BOILER TUBES Original Filed April 16. 1918 3 Sheets-Sheet 2 UDELDEJD EIEJUDDUEI INVENTOR gyi/ w 49 J ATTORN EYS Oct. 18, 1932. D. s. JACOBUS 1,833,294

SERIES "BOILER WIT SUPERHEATER BETWEEN BOILER TUBES Original Filed April 16. 1918 3 Sheets-Sheet L;-

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)JFWENTOR BY W 6% FJM ATTORNEYS 77 Patented Oct. 18, 1932 UNITED STATES PATENT OFFICE.

DAVID S. IACOBUS, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO THE BABCOGK & WILCOX COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION 01 NEW JERSEY SERIES BOILER WITH SUPERHEATER BETWEEN BOILER TUBES Original application filed April 16, 1918, Serial No. 228,827. Divided and this application filed. September 19,

1928. Serial This is a division of my application Serial No. 228,827, filed April 16, 1918. The invention relates especially to the location of the superheater in' a series boiler and will be understood from the description in, connection with the accompanying drawings in which Fig. 1 is a diagrammatic sectional side elevation showing an illustrative embodiment of the invention in a boiler that is stoker fired;

Fig. 2 is a similar view showing a modification with some of the parts omitted; and Fig. 3 is a similar view showing another modification of the invention in a boiler that is provided with oil burners.

In the preferred form of my invention, the

boiler comprises a series of boilerheader boxes to which tubes are connected, the tubes being. preferably of U-form, extending upwardly from the headers.

-A part of the tubes are economizer tubes, part of the tubes are boiler tubes, and part of the tubes are superheater tubes for superheating the steam after it'has been separated from the water with which it flows through the boiler tubes. The superheater tubes are located between the boiler tubes in a pass for versely extending header boxes 2 is located along the lower side of the flue 1 and U-tubes 3 extending upwardly from the'header boxes 2 connect the same. The header boxes 2 are preferably transverse to the flow of the gas and are protected therefrom by the refractory bottom 4 of the furnace chamber or flue.

There is no definite line of division between the economizer portion of the boiler and the boiler itself. Variations in the rate of feed of the boiler, the temperature of the feed water,

used with boilers as the carrying of a small I amount of moisture by the steam into the superheater is an ordinary occurrence.

In Fig. 1 the economizer portion A is made up of the tubes most remote from the source of heat which is indicated as a furnace 5 having a grate 6. B indicates a portion of the boiler tubes that is the evaporating surface, and 0 represents the remainder of the boiler tubes which are nearest the source of heat. The superheater tubes S are located between the portion B and the portion C of the boiler tubes. The off-take 7 for the flue gases is shown at the right. Hottest gases flow over the hottest boilenheating surface and coldest gases over the coldest surface thereby embodying the so-called counterflow principle. The feed water enters the boiler through the pipe 8 leading into the rearmost header box of the economizer portion A. This water flows thence through the U-shaped tubes 3 and the successive boxes of the series toward the furnace end, the water or the combined steam and water pass forwardly into the successive boxes 2 and tubes 3 to the header 9 which is the foremost header of the boiler tubes proper. with a regulated amount of water passes down through pipe 11 into a separating tank 12, the pipe 11 preferably having a handcontrolled valve. A pipe 15 leads from the steam space of the separator 12 to the rear header 16 of the superheater S1 From the superheater headen16 the steam'iiows through the U-tubes of the superheater into the header 18 from which it flows through the outlet pipe 19. By locating the superheater in this position, there is less dan er of burning the superheater tubes than in oilers of the From this header 9 the steam sort where the hottest gases flow over the superheater tubes. The counterflow principle may be'retained both in the boiler portion and the superheater portion.

The water feed to the ecpnomizer and boiler is controlledin the following manner: The separator tank 12 is shown as a horizontal cylinder or drum and the amount of feed water admitted to the boiler through the pipe 8 is regulated by a feed regulating device 20 of well-known construction so as to maintain approximately constant level of water in the separator 12. The water from the separator passes through the valved pipe 21 to the feed tank 22, a coil 23rbeing used to transmit the heat from the water passing from the separator 12 into the feed tank 22 and prevent loss of heat through the vapor escaping from the point where-the hotwater from the valve pipe 21 mixes with the water in the feed tank. The feed regulating device 20 is operated in a well-known manner from the container 24 that is connected by tubes 25 to the steam space and water space, respectively, of the separator 12 so that the Water'level in the container 24 will vary in accordance with the water level in the tank 12 and operate the regulator 20 in such a manner that the amount of water forced into the boiler'through the pipe 8 by means of the pump 26 will increase when the level in the tank falls and will decrease. when the level in the separator '12rises.

The frictional resistancemf the water and steam flowing through the series boiler is a material factor and the pressure of the feed water entering through the pipe 8 must be sufiiciently high to overcomethe frictional resistance of the flow. The'frictional resistance varies greatly, increasing with the load and where a constant pressure is maintained in the steam discharged from the boiler, the pressure of the feed water entering into the pipe 8 must be correspondingly varied. The steam andwater from the portion 9 enter the separator 12 where the two separate and the steam passes up through the pipe 15 to the header box 16 of the header and thence through the superheater and out through pipe 19.

In the modification shown in Fig. 2 the parts are similar to those above described and the separating tank, feed pump, etc. have not been shown. In this modification, however,

being heated by a grate. The parts corresponding to the parts in the illustrative embodiments already described are marked with the same reference characters to which the subscript 3 is applied. The boiler portion is divided into two sections B and G with the superheater 8;, between them so that the hot gases from the furnace contact with the portion C of the boiler or evaporating tubes, thence pass over the superheater tubes S thence over the boiler tubes B and thence over the economizer tubes A before reaching the up-take 7 The oil burners 29 may be spaced along the front of the furnace, part of which is broken away in the drawings. Or a stoker or hand-fired grate may be used in this and the other embodiments of the invention.

In the form shown in Fig. 3 the feed water passesthrough the pipe 8 to the rear header box 2 and thence flows upwardly through the economizer tubes A and thence downwardly to the header box 30. From this header box the water, then flows upwardly through the tubes 31 into the header 32. The headers 32 are at a slightly higher level than the headers 30 and the tubes 31 are spaced alternately with reference to the downtake tubes leading into the header box 30. The succeeding arrangement is similar, the downflow tubes being spaced alternately with the uptake tubes of each box until the header 33 is reached. From this header the steam and water flow through tubes 34 which have wider bends bridging the superheater tubes S and entering the header 35. From the header 35 the steam and water flow progressively through the boiler tubes C and finally enter the header 9 From this header the steam and water pass through a series of pipe con nections 36 into a cross pipe 37. The water is separated from the steam in this cross pipe and the water flows through a number of small pipe connections 38 through the valve connection 39 and to the tank 12 From the separating pipe 37 the steam from which the greater part, or all of the water, has been separated passes upwardly through the small, pipes 40 into the superheater header 4:1. From this header the steam passes through superheater tubes into the superheater header 42 from which it is taken away. The level of water in the tank 12 may be maintained in a manner already described in connection with Fig. 1. The Water in the tank 12 may be led oif through the pipe 43 to a feed tank and recirculated as above described. A

blow-off connection 44 is provided for the of the invention, any of these special features may be used on any of the forms shown on either form of my invention. I v

The. changes in my invention result from overcoming a number of the difliculties incident to series of boilers and the obtainingof the features described therein. Utilizing of the frictional resistance through flow through the various sections, comprising the economizer section, the evaporating section, and the superheater section is an important feature. In ordinary economizer practice the temperature of the water delivered by the economizer is kept below the steaming point, since if the water in the economizer reaches this point it will cause this water to belch over from the economizer.

This will at once cause a rise in the water level of the boiler and the film will naturally partly close the feed valve in the boiler to reduce the flow thereinto. Cutting down the flow of the feed water will cause still more boiling and belching over of the water from the economizer and eventually, if the water falls in the boiler, the economizer will be partly emptied. It will take considerable time to fill the economizer during which time no Water could enter the boiler, this possibly resulting in a dangerously low water level therein.

In the case of my series boiler the economizer portion is at all times steaming where it joins the steam forming portion. If the flow of the water through the economizer section is freer than it should be there will be a belching action similar to that in ordinary economizers.

I also find that in this type of boilers it is -of advantage to employ vertical tubes, as

there is less tendency of the tubes to warp and bend through the action of the heat than where the tubes extend horizontally. It is also advantageous to distribute the water retained in the boiler on suddenly shutting down the boiler, at as many points along the length of the boiler as possible. These features are included in the structure shown with vertical loops and the distribution of the water at a number of points is also embodied in the structure where the loops are presented in a generally horizontal position or at an angle to the horizontal.

One important feature of my boiler is that of withdrawing steam and water to a separating tank or vessel in which the Water is separated from the steam. Where a superheater is used, the steam is thus taken in a comparatively dry state to the superheater. The provision of this tank makes it possible to carry a much more uniform degree of superheating and a more uniform pressure than could be obtained without the separating receptacle.

-The tank also serves a useful purpose where there are impurities in the water, as the steam, free or practically free from impurities, flows from the separating tank into the superheater, the impurities collecting in the water.

I claim:

1. A drumless boiler including a source of heat, a gas passage, water tubes in said passage connected for progressive flow from the cooler to the hotter end of said passage, a superheater in said passage nearer the hotter end thereof, some of said tubes forming a superheater in said passage nearer the hotter end thereof, some ofsaid tubes forming a screen for the protection of the superheater, said superheater receiving steam from the tubes in the hotter end of said passage, means between the superheater and the tubes delineating the location at which saturated steam generation ceases, and means forcing more water through the tubes preceding the superheater than can be evaporated thereby.

3. In a steam boiler, a gas flue, tubes disposed in said flue and connected for continuous progressive fluid flow thercthrough from one end to the other countercurrent to the flow of gases through said flue, means causing water andsteam to be discharged from the end of said tubes opposite the inlet, a steam and water separator receiving said discharge, and a superheater constituted of a similar group of tubes and receiving steam from said separator and disposed intermediate the ends of the first mentioned tubes yvith respect to location in said flue.

DAVID S. JAOOBUS.

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