US1148543A

US1148543A - Boiler water-back.

Info

Publication number: US1148543A
Application number: US70433012A
Authority: US
Inventors: William F Sellers
Original assignee: EDGE MOOR IRON Co
Current assignee: EDGE MOOR IRON Co
Priority date: 1912-06-18
Filing date: 1912-06-18
Publication date: 1915-08-03
Anticipated expiration: 1932-08-03

Description

W. F. SELLERS.

BOILER WATER BACK. APPLICATION man JUNE 18, 1912.

1,148,543. Patented Aug. 3, 1915.

2 SHEETS SHEET l.

INVENTOR WITNESSES 1 v ATTORNEY :QLUMBIA PLANOLIRAPH Cu WASHINGTON, n. c.

W. F. SELLERS.

BOILER WATER BACK. APPLICATION FILED JUNE 18.1912.

Patented Aug. 3, 1915.

2 SHEETS-SHEET 2.

ATTORNEY WITNESSES 55m r I COLUMBIA PLANOGBAPH COuWASHINGTON, D. c.

pnrrnn srarns PATENT onnien VVILLIAJVI F. SELLERS, OF EDGEMOOR, DELAWARE, ASSIGNOR TO EDGE M003. IRON COlvIPANY, OF EDGEMOOR, DELAWARE, A CORPORATION OF DELAWARE.

BOILER WATER-BACK.

Specification of Letters Patent.

Patented Aug. 3, 1915.

To all whom it may concern Be it known that 1, WILLIAM F. SELLERS, a citizen of the United States, residing in Edgemoor, Brandywine Hundred, county of New Castle, and State of Delaware, have invented a certain new and useful Improvement in Boiler WV-atenBacks, of which the following is a true and exact description, reference being had to the accompanying drawings, which form a part thereof.

y present invention relates to boilers such as are employed in the generation of steam for power purposes, and particularly to the construction and arrangement of the water back with its pipe connections to the boiler prop er which it is frequently found desirable to employ in connection with the furnace chamber of such a boiler.

The primary object of my invention is to provide a simple and efi'ective boiler construction in which the water back extends into the boiler housing from one side of the latter, and has the necessary two circulating pipe connections to the boiler proper, each leading from the one outer externally exposed end of the water back, and in which the water back and its pipe connections are so constructed and arranged that the water back may be taken apart for cleaning or re pairs in a simple and expeditious manner, and without destruction of, or injury to any portion of the boiler housing.

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, however, and of the advantages possessed by it, reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described various forms of apparatus embodying my invention. v

Of the drawings, Figure l is a sectional elevation of a water tube boiler equipped with my new invention, Fig. 2 is an end elevation of the externally exposed end of the water back, Fig. 3 is a partial sectional elevation of the boiler, the section being taken on a plane corresponding to the line 33 of Fig. 2, Fig. 4 is a section of the water back taken on the line 4.i of Fig. 3, and Fig. 5 is a longitudinal section of a portion of a modified form of Water back. y In Fig. l of the drawings, I have illus trated the use of my improved water back in a. water tube boiler of well known type. It

is to be understood, however, that the improved water back is capable of effective utilization in many different types of boilers. As shown in Fig. 1, the boiler proper comprises inclined water tubes A connected at their opposite ends to an upper front header B and a lower rear header C. The two headers are also connected above the water tubes by the steam and water drum D. The boiler is inclosed in a housing E of the usual type, and F represents transverse masonry, bridge or battle wall pertaining to the furnace chamber. G represents the grate which, in the particular type of boiler construction illustrated, is in the form of an endless belt. My improved water back, in the form shown, comprises a horizontal tube H which extends into the boiler housing from one side of the latter and lies between the horizontal portion of the baflle wall F and the end of the grate G, and has for its primary function to prevent hot coals on the traveling grate from being carried by the latter into the position in which they may fall off the rear end of the grate. The water back tube H projects through one side wall E of the boiler housing, and has its outer exposed end provided with a flange H. The inner end of the tube H, which is closed as indicated at H? extends into and is supported by the wall E at the opposite side of the boiler from the wall E. The flange H at the expos d outer end of the tube H is detachably connected to the flange J of a fitting J. The latter is formed with a chamber J communicating with and forming an ex tension of the interior passage of the tube H. From the chamber J leads a lateral port or passage J and the fitting is provided with a flange J adapted to be detachably connected to the flange at the end of the pipe K which connects the port J to the front header B of theboiler adjacent the upper end of that header. The fitting J is also provided at its outer end with a chamber J which, as shown, is coaxial with, but of larger diameter than the chamber J and the chambers J and J are connected by a passage J S which, as shown, is slightly smaller in diameter than the bore of the tube H. A port J leads from the chamber J of the fitting J, and the fitting is provided with a flange J 7 adapted to be detachwater through ably secured to the flanged end of the pipe L, which connects the port J to the rear header 0 of the boiler adjacent to the bottom of the header. As shown,

is formed with a flange J against, which may be detachably secured a cover plate J which normally closes the outer end of the chamber J Within the tube His placed a tube I, the outer end of which is connected to the fitting J in such manner as to prevent direct communication between the chambers J and J At its inner end the tube I is open and terminates short of the closed end H of the pipe H so that water passing from the rear header C of the pipe L and the port J 6 to the chamber J 5 of the fitting J, may pass from the latter through the channel formed by the tube I to the inner end of the waterback, and from thence may flow back to the chamber J 2 of the fitting J, through the channel formed by the annular space between the outer wall of the tube I into the inner wall of the tube II. From the chamber J the water may pass to the front header B of the boiler through the port J 3 and the pipe K.

In the particular form of apparatus shown, the connection between the outer end of the tube I and the fitting J comprises a collar I secured to the outer end of the tube I and having a body portion fitting snugly in the passage J and a flange which abuts against the inner end wall of the chamber J Projections J formed on the inner side of the cover plate J normally bears against the outer end of the tube I and prevents its axial displacement. It will be understood that there is no necessity whatever for making an absolutely tight joint between the outer end of the tube I and the fitting J. The difference between the pressures in the chambers J 2 and J 5 is slight, and any slight leakage which may occur from one of the chambers into the other through the joint between the flanged end of the tube I and the fitting J would have no appreciable effect on' the efiiciency of the apparatus.

To prevent the inner tube I from sagging, spacing provisions may be made whereby the tube I is supported from the tube H at one or more points along its length. These spacers may advantageously be formed as shown of pieces of band metal M bent snugly about the pipe I and having ends 'M bent away from the tube to form feet bearing against the inner wall of the tube H.

With the arrangement described, it will be apparent that an effective circulation of the water back is obtained by the gravity flow of the relatively cool water from the lower end of the'rear header C through the pipe L to the water back, the water, after being heated in the water back, passing from the latter through the pipe the fitting J boiler through the K to the upper portion of the front header B. i

It will be apparent to those skilled in the art that the water back may be readily taken apart for cleaning or repairs without disturbing the walls of the boiler housing in any way. This taking apart of the water back may be effected without any disturbance of the pipe, connections by simply removing the cover plate J the tube I. It will be understood that the provisions employed for. spacing the tube I centrally with respect to the tube H should be of such a character as not to interfere with the withdrawal of thepipe I. In the form shown in the drawings, the spacing members M are of such a size relative to the passage way J that they readily pass through the latter when the tube ,I is slightly displaced laterally position in which it is coaxial with the tube A. The tube I may be so laterally displaced of course as soon as the enlarged flanged end I passes out of the fitting J.

Instead of'taking the water back apart by removing the cover plate J and withdrawing the tube I through the outer end of the fitting, the fitting J may be uncoupled from the pipe H and the pipes J and K, and the fitting J and the tube I can then be moved bodily away from the tube H. A very important advantage of my improved water back arrangement arises from the fact that it is common practice to arrange batteries of boilers in pairs in which case, as indicated in Fig. 3, the housing wall E is common to and serves as a central dividing wall between the furnace chambers of the two boilers. Heretofore in such boilers, water back consisting of a tube extending transversely through the furnace chamber of each boiler and connected at one end to the boiler proper by a pipe embedded in the wall E This arrangement is open to the serious objection that the pipe connection embedded in the central wall of the boiler housing is exposed 'to undesirably high temperatures and deteriorates rapidly, and, moreover, this pipe cannot be gotten at or removed for cleaning or repairs without the practical destruction in whole or in part of the central wall. lVith my'arrange ment, the water back and its pipe connections between the water back and the boiler proper are not exposed to the high temperatures of the interior of the boiler housing.

Where the space between the outer surface of theside'wall E of the boiler housing and an adjacent boiler housing or other immovable apparatus or an adjacent wall of the boiler roomisrestricted, it may sometimes be desirable to form the tube I in de tachable sections a i as shown in Fig. 5. These sections may be detachably connected and withdrawing from its normal it has'been the practice to employ a w together as by means of the threaded collars N. It will be understood that there is no more necessity for making perfectly tight joints between the adjacent ends of adjacent sections 2' than there is for making a perfectly tight joint between the outer end of the tube I and the fitting J.

lVith the arrangement described, the cross sectional area of the annular space between the tubes I and H may well be made equal to, or even less than the cross sectional area of the pipes L and K with the advantageous result that the flow velocity of the water through the annular inter-tube space will be made equal to or even higher than the velocity of the water through the tubes L and K. Those skilled in the art will understand that the rapidity of flow of the water through the hottest portions of the apparatus thus obtained and the film-like character of the stream in which it flows, increase the rapidity with which heat is abstracted from the tube H as is desirable in order to keep down the temperature of the latter. The relatively rapid flow of water through the water back and particularly through the hottest portion thereof is advantageous also in that it tends to reduce the deposit of impurities in the water back thus prolonging the intervals permissible between successive cleaning operations and adding to the safety of the apparatus.

Another important characteristic of my water back construction and arrangement is the provision of a free return passage to the boiler from the water back for the steam forming in the water back as well as for the water passing through the water back, and the avoidance of all pockets in the water back in which steam may collect.

It will be apparent that with the water back construction disclosed, the tubes H and I are free to expand and contract as they vary in temperature independently of each other, and without subjecting any portion of the water back to undesirable strains. Those skilled in the art will understand that the fitting J may readily be cast from a single adjusting pattern with the passages J and J at any angle desired, thus greatly facilitating the use of my improved water back in boilers of different types and shapes. v lVhile in accordance with the provisions of the statutes I have illustrated and described the best forms of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed; without departing from the spirit of my invention, and that certain features of the invention may sometimes be employed with advantage without a corresponding use of other features of the invention.

Having now described my invention what I claim as new and desire to secure by Letters Patent is, I

1. The combination with a boiler proper, its housing and furnace chamber, of a water back projecting into and removable from the furnace chamber through an outer wall f the boiler housing and formed with two channels communicating at the inner end of the water back, and pipes detachably connected to the outer end of the Water back externally of the boiler housing and connecting one of said channels to the boiler proper at one point and the other channel to the boiler proper at another point.

2. The combination with a boiler proper, its housing and furnace chamber, of a water back projecting into and removable from the furnace chamber'through an outer Wall of the boiler housing, and comprising pair of tubes arranged one within the other with a space between the outer wall of the inner tube and the inner wall of the outer tube which connects at its inner end with the interior of the inner tube, and means detachably connected to the water back externally of the boiler housing and to the boiler providing a water supply passage leading to the interior of said inner tube from the boiler, and providing a free return passage from the inter-tube space for water and steam said return passage opening to the boiler at a level above that at which said supply passage opens to the boiler.

3. The combination with a boiler proper, its housing and furnace chamber, of a water back projecting into and removable from the furnace chamber through an outer wall of said housing and comprising a pair of tubes separated from each other by an inter tube space communicating with the interior of the inner tube at the inner end of the water back, a fitting to which the outer ends of the two tubes are connected and formed with one chamber surrounding the inner tube and communicating with the inter-tube space and with a second chamber communicating with the interior of the inner tube, and conduits detachably secured to said fitting and connecting the two chambers to different portions of the boiler proper.

4. The combination with a boiler proper, its housing and furnace chamber, of a water back projecting into the furnace chamber through an outer wall of said housing and comprising a pair of tubes separated from each other by an inter-tube space communicating with the interior of the inner tube at the inner end of the water back, a fitting forming a means ends of the two tubes are detachably connected and formed with two passages communicating one with the inter-tube space and the other with the interior of the inner tube, and conduit connections leading from by which the outer the two passages to diiierent portions of the boiler proper, said inner tube being divided into separable longitudinal sections.

5. The combination with a boiler proper, its housing and furnace chamber, of a water back projecting into and removable from the furnace chamber through an outer wall of said housing and-comprising a pair of tubes separated from'each other by an intertube space communicat ng wlth the interior of the inner tube at the inner end of the water back, a fitting to which the outer ends of the two tubes are connected and formed with two passages communicating one with the inter-tube space and'the other with the interior of the inner tube, means interposed between the two tubes and spacing them apart, and conduits detachably secured to said fittings and connecting the two passages to different portions of the boiler proper.

6. A water back adapted to project into the interior of a boiler through the boiler housing and comprising a pair of tubes arranged one within the other and separated from each other by an inter-tube space communicating with the interior of the inner tubeat the inner end of the water back, and a fitting to which the outer ends of the two tubes are connected, said fitting being Copies of this patent may be obtained for formed with one chamber surrounding the inner tube, and communicating with inner-tube space and with a second chamber communicating with the interior of the inner tube, and having provisions for detachably connecting to said fitting two pipes, one communicating with one, and

, the other with the second of said chambers.

7 A water back adapted to project into the interior of a boiler through the boiler housing, and comprising a pair of tubes arranged one within the other and separated from each other by an inter-tube space communicating with the interior of the inner tube at the inner end of the water back, a hollow fitting, means for detachably connecting the outer end of said outer tube to said fitting, means for securing the outer end of said'inner tube into said fitting so that said inner tube divides the interior of said fitting into two chambers communicating one with said inner tube and the other with said inter-tube space, and means for detachably connecting two pipes to said fitting, one communicating with one, and the other with the second of said chambers.

WM. F. SELLERS.

Witnesses ARNOLD KA'rz, D. STEWART.

five cents each, by addressing the Commissioner of Patents,

Washington, D. C.

the