US2877746A

US2877746A - Distributor for boiler heating surfaces

Info

Publication number: US2877746A
Application number: US591634A
Authority: US
Inventors: Oestreich Heinz
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-06-27
Filing date: 1956-06-15
Publication date: 1959-03-17
Anticipated expiration: 1976-03-17

Description

March 17, 1959 H. OESTREICH I 2,877,746

DISTRIBUTOR FOR BOILER HEATING SURFACES Filed June 15, 1956 HEM/z @EsmE/ch' 4, Man);

h-rolue'y Inventor.-

DISTRIBUTOR FOR BOILER HEATING SURFACES Heinz'fles'treich, Hannover-Herrenhausen, Germany, as slgnor to Heinrich Vorkauf, Beriin-Schmargendorf, Germany Application June 15, 1956,,SerisLNo. 591,634 Claims priority, application Germany .lune'27, 1955- 7 Claims. (Cl. 122-406) whereas the tubes more remote from these connections do not receive enough.

The invention aims, therefore, to improve'the water distribution in boilers or steam generators of the mentioned type, andto accomplish such improvement by dividing the water current at the end of a distributor into two' or 'more than two currents and to cause these-currents to enter the distributor over the length of the latter.

Another object of the invention is the provision of means to influence the distribution of the water over the length of the distributor by dividing the water flow, and, in certain instances, to supply a larger quantity, of water to very intensely heated portions than to less heated portions of the heating surface tubes.

A further object of the invention is to prevent totally or partly the throttle losses on account of-suctioneddies taes atent If the below each riser tube from becoming effective over the total length of the distributor, so that such'l'os ses affect, at most, a small number of ,tubes.

In boilers or steam generators according to the invention, the advantage of wide down pipes will be fully utilized inasmuch as the velocity of flow is much higher in :downpipes which are wide and few in numberwithout causing an increase of the pressure drop, than in a larger number of down pipes of small diameter. Owing to the velocity prevailing in the wide down pipes, the kinetic energy of the water can be utilized to cause differences of the water pressure of the individual currents starting therefrom.

According to another object of the invention, special connecting tubes may be provided to the portions of the distributors which are farther remote from the connections of the down pipes, and such connecting tubes are preferably so arranged that they extend from points underneath the connections of the down pipe and the distributor. Such arrangement offers the advantage that owing to the dynamic pressure here created, the water will be forced into the connecting tubes extending from these points. The connecting tubes suitably lead the water to the median part of the distributor where generally in furnaces with rectangular plan, the radiantly heated tubes are more intensely heated than at the ends.

The distributors with their connecting tubes extending from the down pipes may be formed like trellis girders, which have a much higher moment of resistance than a conventional distributor of the same passage cross-see tion. Such distributors, formed as girders, are especially advantageous if they are used as supports of a large heat- 2 ing gsurface; e. g. a large number of banks of tubes, to which the .water is admitted from the distributors. Distribu'tors', formed as trellisgirders, render it possible to carry not only the heating'surface but also fire clay bricks, deflectingwalls or the like;

Further -objects and details of "the invention will be apparent from the description given hereinafter and the accompanying drawing illustrating an embodiment thereof byyway' of example.

In the drawing,

Fig. "l is a longitudinal cross-section of a steam generator incorporating the invention, and

Figs: 2 to 4 are three diiferent distributors of the em bodiment ofFig. 1 in diagrammatic elevations and with the connecting tubes extending between the distributors and the down pipes.

' Referring now to the'drawing.-

Fig.1 shows a steam generator with gravity circulation; however, it is to be understood that the invention is. ap plicable also to other boilers with gravity circulation, such as to certain hot water boilers. The term boiler appears ingv in the claims is, therefore, to be understood to include all kinds of boilers to which the invention is applicable.

'The radiantly heated surface consists of several groups of tubes. The'front wall tubes 11 extend from the water distributor 12. They open into the upper collector 13. The rear wall tubes 14 extend from the distributor 15 to the upper collector. 16. The side wall tubes 17 extend from the lower longitudinal distributor 18 to the upper longitudinal collector 19. The

upper collectors

13, 16 and 19' are'connectedwith the steam drum 20. The namedigroups of

tubes

11,14 and 1'7 substantially line the furnace walls. In a downwardly directed flue, another group 21 is arranged consisting of tubular .elements whioh'are connected to the distributor 22 and open also into .the'c'ollector 16. The heated tube system is supplied with water by the vertical pipes 23 which are not heated and'extend from both ends of the steam drum 20 downward. Furthermore, there areprovided the

return tubes

24 and 25 which bypass the drum and conduct water separated in the upper longitudinal collectors 19, directly to the' lower distributors.

The down pipes 23 and

return pipes

24 and 25 have a relatively large cross section and form, together with the lower'distributors and upper collectors, a tubular frame work carrying the heating surfaces. In this type of boil.- er "structure, a relatively high velocity prevails in its few down and return pipes.- In order to avoid current-losses due to these high water velocities at the points where the water enters the lower distributors, special admission tubes to the distributors are provided according to the invention.

For this purpose, in Fig. 1, special admission tubes 26 lead from the lower ends of the down pipes 23 and the return pipes 24 to the lower longitudinal distributor 18 so that this distributor 18, on the one hand, receives water from its ends directly through the down and return pipes and, on the other hand, through the admission tubes 26 which, however, conduct the water to the median part of the distributor where, as well known, the most intensely radiantly heated tubes are connected. Through these admission tubes 26 the distribution of the water over the length of the distributor 18 will be essentially improved and the current loss decreased.

The distribution of the water to the front wall distributor 12 is provided in a similar manner.

Another tube 27 is positioned parallel to the distributor 12. Both tubes, the distributor 12 and also the tube 27, are connected at their ends to the water circulation by means of the connecting tube 28.

on alarger scale.

It will be seen that the distributor 12 is connected at its ends with the connecting tubes 28. The admission tube 27 is located above distributor 12. The intermediate tubes 29 extend from this tube 27 so that water is admitted to the distributor 12 not only from its ends in the conventional manner, but also from the tube 27 through the tubes 29 whereby the median evaporating tubes, i. e. particularly the most intensely heated ones, receive additional water.

Fig. 3 shows the admission of the water to the rear wall distributor 15. Both ends of this distributor are connected to the return tubes 24.

Above the distributor and parallel to the latter, the admission tube 30 is located which similarly, as described hereinbefore, is connected with the distributor 15 through tube 29 so that through these tubes additional water can flow to the median portion of the distributor. Both the lateral tubes 29 are inclined which is favorable from the view point of the flow. It is also to be noted that a kind of trellis girder is formed by the intermediate tubes 29, the distributor tube 15 and the admission tube 30. This type of structure enables it to be subjected also to high mechanical stresses or loads. Thus, in the present case, this trellis girder serves to support the bundle of tubes 21.

Fig. 4, finally, shows the admission of the water to the distributor 22 of the set of tubes 21. structure described hereinbefore, the distributor 22 is con nected with its ends to the return tubes 25. The tube 31 is provided as an additional admission tube which is also connected with the distributor 22 by the intermediate tubes 29. Also in this case, tube 31 constituting the lower beam, together with distributor 22 forms a girder which is braced by the intermediate tubes 29 so that, in addition to the improved water distribution, a greater strength of the distributor 22 is achieved to support the set of tubes 21. i

It will be apparent to those skilled in the art that many alterations and modifications of the structure shown and hereinbefore described can be made without departure from the essence and spirit of the invention which for this reason shall not be limited but by the scope of the appended claims.

I claim:

l. In a boiler with gravity circulation, the combination of a pair of water-conducting down pipes, a substantially horizontal distributor connected with its ends to said down pipes, respectively, a plurality of risers extending from said distributor, a water admitting tube substantially in a vertical plane with and at a distance from said dis tributor and being in communication with said down pipes,

Similar to the v respectively, and a plurality of connecting tubes connecting said water-admitting tube to said distributor intermediate its ends.

2. A combination of boiler tubes as in claim 1, said water admitting tube being substantially parallel with said distributor.

3. A combination of boiler tubes as in claim 1, said dis. tributor, said water admitting tube and said plurality of connecting tubes being formed substantially as a trellis girder adapted to support other weighty portions of said boiler.

4. A combination of boiler tubes as in claim 1, said distributor being substantially horizontal and said water admitting tube being parallel to said distributor and connected to said down pipes at a distance above the connection of said distributor with said down pipes.

5. A combination of boiler tubes as in claim 1, wherein at least two of said connecting tubes are inclined.

6. In a boiler with gravity circulation, the combination of a pair of water conducting vertical down pipes, a substantially horizontal distributor parallel to the plane defined by said down pipes, tubular connecting pieces between the ends of said distributor and said down pipes, respectively, a plurality of risers extending from said distributor, two upright tubes connected with their ends to the ends, respectively, of said distributor, another tube substantially parallel to said distributor and connected with its ends to the upper ends, respectively, of said upright tubes, and a plurality of connecting tubes between and opening into said distributor and said parallel tube intermediate their ends.

7. In a boiler with gravity circulation, the combination of a pair of water conducting down pipes in corners of said boiler, a substantially horizontal distributor cndwise connected to the lower ends of said down pipes, a plurality of risers extending from said distributor, a tube in the plane of said distributor and said down pipes andvconnected to the latter at their lower ends, said tube being bent so as to have a lowest point underneath the middle of said distributor, and at least three connecting tubes, one of which connecting the middle of said distributor and said first mentioned tube and the other connecting tubes connecting said distributor and said first mentioned tube intermediate their ends and their middles.

References Cited in the file of this patent UNITED STATES PATENTS 2,231,872 Bailey et al. Feb. 18, 1941 FOREIGN PATENTS 580,671 Great Britain Sept. 16, 1946 673,154 Great Britain June 4, 1952