US1355687A - Steam-generator - Google Patents

Description

J. F. OTIS. STEAM GENERATOR. APPLICATION FILED JAN.13, 1917.

' Patented Oct. 12,1920.

UNITED S ATES PATENT OFFICE.

JOHN 1. cans, or oswne nnw YORK.

STEAM-GENERATOR.

Patented Oct. 12, 1920.

Original application filed April 11, 1914, Serial No. 831,137. Divided and this application filed January 13,

. T all whom it may concern:

. new and useful Improvements in and Relating to Steam-Generators, of which the following is a specification, this application being a division of my application filed April 11, 1914, Se. No. 831,137, for steami generators.

This invention relates to certain improvements in steam generators; and the objects and nature of the invention will be readily understood by those skilled in the art in p the light of the'following explanation of the accompanying drawings illustrating "what I now believe to be the preferred em bodiments and mechanical expressions of my invention from among other formations,.ar-

' rangements and constructions within the spirit and scope of the invention.

' The object of the invention is to arrange a superheater as close as possible to the upper surface of the top flue sheet and within the flame issuing from the fire tubes to utilize the otherwise waste heat for superheating the steam and to maintain the superheater within a zone of the highest possible temperature; and to so form, construct 1 and support the superheater as to. gain the greatest possible advantage from this high temperature Without obstructing and disturbing the draft through and without causing back pressure within said tubes and withoutexcessive deposits onthesuperheater and sheet and consequent difficulties; and to so form the superheater both internally. and

' externally as to subdivide and distribute thesteam in amanner to gain the full advantageof said high temperature in superheating the generated thereby.

steam and at the same time to produceasuperheaterof extreme simplicity and strength against the expansive forceof'the-steam; 1

"so'formed that it can be locatedclose to the V and the plate isformed with perforations lVith" these objects in view, the superheater of my invention isjcharacterized in whole or in part by a casting or other body top tubesheet of the boiler without obstructthe draft through the firew'tub'es and so formed and balanced with respect to a central vertical bottom steam inlet that the sution to the draft; said superheat'er' embody-- above said flue sheet.

Serial No. 142,215.

ing uniformly spaced and distributed long rounded comparatively small tube-like members that are exceedingly strong against internal pressure by reason of their rounded formation and that do not obstruct the draft because of their small diameter and rounded formation and that are internally formed to distribute the steam from said inlet in long small outgoing streams and correspondng parallel long small return streams lead- 1ng.to asingle central steam outlet, with abrupt transverse edges exposed to said steam and traversed thereby at the junctions between the outgoing and return streams of steam. Referring to the accompanying drawlugs;-

Figure'l, 1s a vertical section through a.

Fig. 3, is a section on the line'3'3,'

Fig. 2.

In the particular example illustrated, I show part of an upright steam generator having upright inclosing shell or wall 2, and horizontal crown or top flue sheet 1, in which the upper'ends of a multiplicity of vertical fire'tubes 7, are secured and through which they open into the combustion chamber 7 I These fire tubes extend through the steam .and water spaces within the boiler shell and attheir lower endsare secured in a suitable bottom head or flue sheet (not shown) and extend therethrough and open into the fire box or chamber of the boiler to carry off the burning gases and smoke and'deliver them into the combustion chamber above flue sheet 1 after subjecting the water and steamv to the heat These fire tubes pass through aor separator plate 16, spanning the steam space of the boiler a shortdistance below flue sheet 1:, and suitably secured toand carried by shell 1 The platelG fits the inner surfaceof shell 2 to preferably" form a steam tight joint,

for the passage of; the fire tubes, the. plate being otherwise imperforate. The perforae tions closely receive the fire tubes toform restricted thin spaces between the surfaces of the fire tubes and the edges of the platesurrounding the tubes throughwhich the steam through the center of the flue sheet 1,v and this nipple rises from said flue sheet and passes in films. The steam is more or less superheated in passing through these perforations along the hot surfaces of the steam and moisture is evaporated therefrom. The plate 16 becomes highly heated and tends to flash water carried by the steam into vapor, and furthermore, the edges of the plate at the holes therethrough will tend to catch water carried by the steam and separate the same from the steam.

I provide a combustion or hot gas chamber at the top of the upper flue sheet 1, and into which the flues or tubes 7 will discharge .the hot or-burning products from the combustion chamber. For instance, I show an upwardly extending hood 18 mounted on the I upper end of the boiler and at the upper end having a suitable outlet or discharge 19. I

provide means for passing the steam from 20 the boiler through the combustion chamber within this hood for the purpose of separating all water from the steam and thoroughly superheating the .steam before it passes off to perform its work whether for heating or power purposes. 1 1

The boiler is provided with a vertical steam outlet pipe or nipple 20 opening into the steam space of the boiler approximately .'the passage of steam therefrom.

The superheater preferably consists of several longitudinally elongated hollow arms or bodies 22, radiating from a common hollow center or hub 23, and the interiors of the hub and arms are spanned by animperforate bafliing plate or diaphragm 24 preferably located centrally or midway between the bottom and bottom walls of the arms and hub. The interiors of the'arms 22 open into the interior of the hub and the arms are otherwise imperforate and the bafiling plate spans the hub dividing the interior thereof. into a bottom steam. inlet space receiving the steam pipe 20 and top steam outlet space receiving outletlpipe 21. The plate extends from the hub longitudinally within the arms but terminates short of the outer ends of the arms so that each arm has a "longitudinal steam passage leading outwardly from the inlet steam space of the hub to a vertical steam port or passage 25 beyond 'intense heat under the hood the end of the bafliing plate and at the outer end of the arm, and a longitudinal return steam passage above the baflling plate and from port 25 to the upper steam space of the hub.

The steam enters the superheater vertically through pipe 20, and impinges directly against the baflie plate and is then divided into outwardly flowing streamsin the several arms and also return flowing streams in said arms, and is thereby subjected to the and is thoroughly superheated.

The surfaces and edges of the bafliing plate will tend to separate all water from the steam and vaporize and superheat the same. The superheater is arranged directly above the fire tubes within the zone and influence of the hot burning gases issuing from said tubes and the heat of such combustion'is thus fully utilized in superheating the steam sub-divided as it is within and by the superheater.

The superheater with its baffling plate is preferably cast in one piece or otherwi formed integral of. suitable'metal.

It is evident that various changes, modi fications and variations might be resorted'to without departing from the spirit and scope of my invention and hence I do not wish to limit myself to the exact disclosures hereof.

What I claim is I I 1. A superheater constructed for-location close to the upper surface of the top tube sheet of a vertical fire tube boiler and to be supported from said sheet by a central vertical nipple forming the steam passage from the boiler to the superheater; saidsuperheater consisting of a central hollow hub having horizontally-elongated hollow arms radiating therefrom and opening thereinto and supportedthereby; said arms being uniformly spaced, closed at their outer ends, small in diameter and substantially cylindrical; the hub and arms being internally sub-divided into upper and lower Y steam chambers and small-elongated passages, the passages of each arm communicating at the outer end of thearm, said hub having a central vertical bottom steam. supply opening and a central vertical top steam outlet openmg. y V

2. A vertical fire-tube boiler having a steam-outlet from its top tube-sheet, and a superheater arranged horizontally over said tubesheet and receiving the steam from 7 said outlet; said superheater composed of a spider-like hollow body formed to avoid obstructing the draft from the fire tubes, and internally formed tojprovide uniformly distributed small elongated outgoingsteam passages or the steam received-from said outlet and uniformly. distributed small elongated return passages for the steam from.

said outgoing passages and having a steam discharge receiving the steam from said several return passages. v

3. A superheater having a central vertical bottom steam inlet and acentral vertical top 'steam outlet and embodying uniformly spaced and distributed tube-like longitudinally-elongated arms internally formed to provide long small outgoing steam passages for the steam from said inlet and corresponding small long return steam passages 10 JOHN F. OTIS.

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