вход по аккаунту


Патент USA US2119451

код для вставки
May 31, 1938.‘
~Filed June 29, 1936
- 2 sheets-sheet 1
May 31, 1938.
'c. s. TURNER
2,1 19,451 '
Filed June 29, 1936 '
2 sheets-sheet? v
WM '
F|G.4. 236
Patented May
Charles S. Turner, Detroit, Mich. _
‘Application. June 29,1936.v Serial No. 81,836
(Cl. 122-481)
This invention relatesto the superheating of provide water regulated superheating of the type.
’ 1s . Claims.
steam, and is particularly directed to improve: indicated, employing a plurality of steam tubes
ment- of the process and apparatusdisclosed in vgrouped about a central or substantially enclosed 1
my PatentNo. 2,000,906, issued May 14,- 1935. ‘ water tube in such manner as to present a main-,_
mum of exposed superheating surface and,pro-,,
Superheaters constructed and operated‘ in ac
tect the water tube ‘when empty, ‘yet so arranged ,
cordance with the disclosure of the patent men-,
tioned are of the radiant type, and may be di
that the water within the central water tube ,
nevertheless e?ectively absorbs‘ heat excess or "
rectly exposed to radiation in the hottest por
tions of the boiler. - They incorporate steam and
unneeded heat from the surface of the steam tubes
water tubes integrated throughout their exposed
before such heat can reach the steam within the ' 10
length. as by welding. In normal operation, the
watt.“ :;: carried at a reduced level in the water
Another important object of this invention is
passage or passages, and the level 'is controllable
to provide in such a. superheater water and».
steam tube elements so structurally and func
tionally inter-related as to incorporate such 15
by an inlet throttle valve to regulate the tem
15 perature of the superheated steam.
The tube
inter-protective function, and allow direct heat
absorption through metal-from the exterior by,
the internal water tube, while heatabsorption:
assemblies are of course arranged in other than
horizontal position, in order to facilitate such
control. When thesteam tubes are empty, as in
starting the boiler, the water tubes are ?ooded,
20 and their‘ heat-absorbing power protects ‘the
by the water tube from. the inner ‘shielded sur-,,
faces of the steam tubes which abut the water
steam tubes against burning out, while when the
tube is greatly restricted.
water is at reduced level in the water tubes, such
In the drawings:
1 is a diagrammatic vertical
> section
tubes are protected by the saturated _steam ‘gen
a vboiler ‘equipped with a radiant superheater as
erated in them and by the excess heat absorb
25 ing capacity of the steam tubes.
sembly constructed, installed, and adapted to
operate. in'accordance with the principles of this
I have found
it desirable, in the construction of such super
heaters, to arrange where ‘possible for disposition
of the steam tubes upon ‘the outside of the as
sembly, in order that an active superheating sur
30 face area as great as possible may be presented
to the source of radiant heat. It is essential,
Figure 2 is a plan view, partly broken away, of
the superheater assembly, constituting a develop
however, if the superheating process is to be
successfully carried out in accordance with the
teachings of the patent, that the water tubes,
35 when and where they contain water, be able to
stantially on the lines 3-3 and 4-4 respectively
of Figure 2, and looking in the direction of the
ment thereof in one plane.
Figures 3 and 4 are cross sections takensubr
Figure 5 is a cross section similar to Figure 3
of a modi?ed form of tube assembly, and
absorb. excess or unneeded heat from the outer,
Figures 6 and 7 are similar cross sections of
heat-exposed surface of the assembly before such
heat can reach the steam, in orderto-prevent
another modi?cation, showing the same adapted
superheating in the portions ofthe apparatus
to construction of different proportions.
Referring now to the drawings, reference char
40 below the water level. Quite naturally, the struc
tures ?rst conceived for. carrying out this process, . acter l0 designates the upper or steam drums of
involved arranging the water passages outside a boiler, whose walls are designated I2, andv
the steampassage or passages, in positions which which is provided with a lower or mud drum l4,‘
appeared best calculated to intercept the heat
45 before it could reach the steam. This, however,_
reduced the exposed superheating surface, due to
the shielding eifect of the water tubes, even when
and where empty. Unless, also, \some means
were provided for limiting heat conduction‘ be
between which and the upper drums water tubes
l5 are shown disposed in more’or less-conven- .
tional arrangement.
Carried by but spaced from the wall‘ l2 and‘
arranged directly above the ?re boxv I6. is a
superheater assembly, generally designated IT in
50 tween the inside abuttingrsurfaces of the steam
Figure 1, comprising a plurality of integrated
and ‘water conduits, the steam lost heat .to'the
steam and water tubes,» arranged vertically in
water, and steam could not ‘be run downwardly
the boiler, although any substantial inclination. _
through the assembly without the occurrence of ' from the horizontal which allows theconvenient
undesirable desuperheating below the water
maintenance of a water level therein will su?ice,
level.‘ The present invention, therefore, aims to ‘
in accordance with the desires of thedesigner of 55
the particular installation. The tube assemblies
terminate at their upper and lower ends in head-'
ers 20—2l, respectively, to which they are welded
as at 26, or otherwise suitably secured. Steam
tubes 23 will be seen to open directly into the
interior of each header, while a continuation 25'
of each central water tube 25 is carried through
the header to a separate header passage as 24
extending along the back of the main header
The central water tube may be fed from the
lower drum l4 by means of a pipe 21 connected to
- the portion 24 of the lower manifold, while the
water supply is controllable by means of valves,
',15 as 28—29, the former thermostatically controlled
in response to the temperature of the output su
perheated steam, and the latter constituting a
hand operable by-pass. The by-pass valve is nor
mally closed, and the thermostatically regulated
20 valve arranged to raise the water-level in re
sponse to a rise of output steam temperature, and
vice versa, in order to maintain the output at any
given temperature. At their upper- ends the
water tubes 25 are connected to the steam
25 spaces of drums ID as by means of a pipe 32, run
ning to the drums from upper water tube header
24. Such steam spaces also supply steam to be
that no return out?ow from the steam tubes to
the weld and then into\the ?ute can be accom
modated. Thus when, as in normal operation,
valve 28 is so regulated as to maintain a reduced
water level in central tube 25 within the zone'of CI
heating, such separation of the integral portions
of tubes 23-25 acts to virtually isolate theminso- ‘
far as heat interchange is concerned, prevent
ing reduction of the temperature of the steam
?owing through the portions of tubes 23 below 10
the water level, while above the water level the
full exposed superheating surface of tubes 23 is
It will also be seen that the water tube
is protected by the steam tubes when’ and where
the former is empty, and that, as stated,_due to 15
the e?icient heat-conductive connections between
the central» passage and the exterior of the as
sembly, the steam tubes when empty are e?ec- _
tively protected by the water which is then pres
ent in the water tube.
In themodi?ed multi-tube assembly shown in
Figure 5, in which analogous portions to those
already described have been given like reference
numerals distinguished by the addition of the
letter “a”, the central water passage is formed of 25
plates 25a of partly cylindrical contour, shaped
to receive steam tubes 23d and partly encircling
superheated to the lower ends of steam tubes 23, . each, the edges of the plates extending outwardly
through a pipe 34 connecting the drum and the
30 lower steam header portion 2|, - although the
steam might be made to ?ow downward through
the assembly rather than upward. The upper
ends of the superheater tubes 23 discharge the
superheated steam through a steam pipe Ill.
The central water tube 25 is provided with
integral ?utes 35, proportioned to provide con
cave channels adapted to receive the steam tubes
23, which are fitted therein and welded, asat 33,
to the tops of the ?utes. The ?utes and tubes
23 are shown as'helically disposed, to render as
uniform as possible the heat absorption by each
tube. The peaks of the ?utes extend outwardly
between the steam tubes,’ and by the welds 33
between each pair of adjacent steam tubes to
form ?ute portions 35a arranged in positions 30
analogous to the locations of the ?utes 35' of the
tube assembly shown in Figure 3. Such out
wardly projecting ?ute-forming portions of the
plates are welded together and to the surfaces
of the tubes between which they extend, as at
33a, and the lack of integral connection between
the water tubes and plates at their other inter
fitted portions inside the assembly similarly pre- '
vents substantial heat ?ow to the central water
passage except from the exposed surface, the ac 40
tion of course resembling that of the ?rst embodi
ment already described.
In Figures 6 and '7 the plate portions 251) are
further modi?ed to provide concave rather than
convex, inner surfaces imparting a substantially
are integrated to the outer surface of the as
sembly. The parts are so proportioned with re
spect to the maximum heat impingement to ' cylindrical interior to the water channel which
which the apparatus is to be subjected and to
the minimum steam and maximum water tem
peratures to be encountered, that when water
50 is contained in central tube 25, it can absorb ex
cessive or unneeded heat from the most remote
parts of the exterior surface of the assembly, in
cluding the steam tubes, before such heat can
reach any steam which may be present in tubes
55 23, thus preventing over superheating of ‘such
steam, in accordance with the design and the
relative temperature conditions. Preferably the
arrangement is such, however, that when the
steam tubes are empty the water can maintain
all portions-thereof at safe temperatures. This
will be seen to be a simple engineering problem
of proportioning the ?utes, tubes and welded
areas in accordance with the conditions encoim
tered in each installation.
The described action is possible because of the
e?iciency of the heat path through the ‘?utes
and the welds to the exposed exteriors of the
steam tubes, while since there is no integral con
nection between the steam tubes and water tubes
except at such externally located welds, heat
transference between their internal inter?tted
portions is impeded to such degree that-no sub—
stantial heat ?ow is possible; The entire heat
path provided by each weld is also required dur-"
75 ing such operation to handle in?owing heat, so
facilitates its cleaning by ordinary Yturbining
methods. Such plates may, as indicated be used
in conjunction with assemblies of different num
bers of steam tubes (23b) , so that the curvature 50
of the inner surfaces ‘of plates 25b may not be
strictly concentric with the axis of the assem
bly, depending upon the arrangement. Such ec
centricity, within limits, however, does not pre
vent proper cleaning, enabling the adaptation .
of the plate units to constructions of diverse pro
portions, ‘as will be readily appreciated.
While it will be apparent that the illustrated
embodiments of my invention herein disclosed
are well calculated to adequately ful?ll the ob— 60
jects and advantages primarily stated, it is to
be understood that the invention is susceptible to
variation, modification and change within the
spirit and scope of the subjoined claims.
What I claim is:
l. A multi-t’ubesuperheater assembly adapted
to be subjected‘ to direct impingement of radiant
heat, comprising a central water tube, a plurality
of substantially parallel longitudinally extending
rib portions integral with and projecting radially
from its exterior wall, a plurality of longitudi
nally extending steam tubes grouped about the
water tube, one arranged in the channel formed
between each pair of adjacent rib portions, the
steam tubes being spaced apart by and having
3 .
their exposed surfaces welded to the peaks of the , duit structure is shielded‘by said tubes and weld;
'rib portions.
ed areas.
superheater assembly as‘ set forth in
8. A multi-conduit superheater tube assembly -
claim 1 in which the rib portions are formed by
radially thickened portions of the water tube wall,
‘and the water passage lies. entirely within the
area bounded by the steam passages.
comprising a control conduit disposed substan
tially centrally and formed of a plurality of lon
gitudinally arranged elongated elements grouped
about a contained area and welded together along
their edges, said elements having channeled ex
3. A superheater assembly asset forth in claim
1, including means for establishing and control
ternal surfaces, and heating tube portions ?tted
10 ling a waterlevel in the water channel, and in
into said channeled surfaces and welded to the 10
which the radial height of the rib portions and
the proportions of the steam tubes, de?ning the \ .
length of the heat paths between-the exposed
exterior of the assembly and the water passage,
_ .
9. A superheater
mbly as set forth in claim
8 in which said heat ng tube portions are secured
together and to the elongated elements by the
15 are so proportioned to the maximum heat im
pingement to which the apparatus is to be sub— '
welds which secure said elements together.
10. A superheater assembly as set forthv in
-jected, and to the steam and watertemperatures,
that cooling water in the water passage, when‘
and where present, may absorb heat from the
20 portions of the exterior surface most remote
claim 8 in which said heating tube portions are ,
secured together and to the elongated-elements
by said same welds which secure said elements
therefrom more rapidly than such heat may be
transmitted to the steam, while the steam tubes
surround the water tubes and act'to protect the
latter when or where empty of water.
25 4. In combination with a steam boiler includ
connection between the heating tubes and said
11. A superheater assembly as set forth in
claim 8 in which said heating tube portions are
secured together and to the elongated elements 25
ing radiant heating means and water-containing
portions, superheating means comprising a multi
tube assembly directly exposed to the radiant
heat and comprising a‘ central water tube having
30 a longitudinally ?uted exterior, a plurality of
steam tubes ?tted into the channel's formed by
said ?utes and welded to the tops thereof, the
steam tubes being spaced by the ?utes, means
for delivering steam to be superheated to said
35 steam tubes from said boiler,‘ regulable means
for delivering water to the“ water passage from
said water-containing portions and for maintain
ing a reduced and controllable water level in said
passage, the welds being located at the exposed
40 surface of the assembly and the other inter?tted
portions of the tubes having distinct walls act
ing to restrict heat transfer therebetween ex
cept at said exposed surface, the proportions of
the ?utes being such, and the steam tubes being
so proportioned to the maximum heat impinge
ment to which the apparatus is to be subjected,
that cooling Water in the water passage, when
and where present, may absorb heat from the
portions of the exterior most remote therefrom
50 rapidly enough to prevent excessive temperatures
in all parts of the tube and unwanted super
heating, while the steam tubes surround the wa
ter tube ‘and act to protect the latter when or
where empty of water.
5. A superheater assembly as set forth in claim
1 in which said water tube is formed of a plu
rality of elongated channeled elements of such
external concavity as to receive the water tubes,
together, said welds forming the only integral 20
by said same welds which secure said elements
together, said welds forming the only integral
connections between the heating tubes and said
elements and being located upon, the outsidev of‘ '
the assembly.
12. A superheater assembly as set forth'in
claim 8 in which said heating tube portions are
secured together and to said elongated elements
by said same welds which secure said elements
together, said welds forming the only integral 35
connections between the heating tubes and said
elements and being located upon the outside of
the assembly, said control conduit being ‘com
pletely enclosed by said welds and tube portions.
13. A superheater assembly as set forth in 40
claim 8 in which the internal surfaces of said
' elongated elements are also channeled substan
tially partly cylindrlcally, and said last-men
tioned channels, when the plates are assembled,
cooperate to provide said control conduit with 45
a substantially cylindrical internal wall.
14. A superheater assembly as set forth in
claim 8 in which the internal surface of each of
said elements is provided with a reentrant sub—
stantially partly cylindrical channel extending 50
substantially the full width of they element;' said
lastginentioned channels, when the elements are '
assembled, cooperating to form a tubular control
conduit having rounded internal walls.
_ 15. A superheater assembly as set forth in 55
claim 8 in which each of said elements is chan
neled both internally and externally, the in-.
ternal» channel in each being of substantially
arranged edge-to~edge,isaid edges projecting be
partly cylindrical form and extending substan-.
60 tween the steam tubes to form the ?utes and be
tlally the full width of the element, said internal 60
ing welded together and to the steam. tubes. channels when the elements are assembled co
throughout their length,
operating to form a tubular control conduit hav
6. A superheater assembly comprising a cen
tral conduit structure having wall portions of
65 variant thickness de?ning longitudinal chan
nels upon its exterior surface, a plurality of tubes
arranged in said channels, thicker. wall portions
of said central conduit structure projecting out
ing rounded internal walls, the external chan
nels being upon lesser radius and adapted to hold
said tubes in spaced relation.
16. A superheater assembly as set forth in
claim 8 in which each of said elements is chané
neled both internally and externally, the inter
nal channel in each being of substantially partly"
ing welded thereto throughout their exposed' cylindrical form and extending'substantially the 70
width of the element, saidinternal channels
length but only adjacent exposed portions, _of full
when the elements are assembled cooperating to
form a tubular control conduit having rounded
70 wardly between the walls of said tubes, and be
said tubes.
'7. A'superheater structure as set forth in claim
75 6 in which the entire surface of said central con
internal walls, the external channels being upon ,
lesser radius and adapted to hold said tubes in 75
nel enclosed by wall portions provided with pro
spaced relation, portions carried by said elements jeeting
rib portions extending ‘longitudinally and
extending outwardly at least part way between
said tubes, said'projecting portions being welded
together and to said tubes.‘
17.. Means as set forth in claim 6 in which said
central conduit structure is formed of a plurality
of sections divided longitudinally in their thicker
areas and'secured together by said same welded
_ connections.
18. A multi-tube superheater assembly adapt
ed to be directly subjected to radiant heat, com
prising integratedsteam. and water tube portions,
the water tube portions including a central chan
in substantial parallelism, said rib portions be
ins spaced from eaehother'to de?ne a plurality
of channels. a steam tubelportion in the‘ iorm
of a separatepipe being arranged‘in each chan
nel and welded to the peaks of the rib portions
on either side thereof, each welded portion be
ing located substantially at the surface of the
assembly, extending longitudinally and ‘uniting
two adjacent steam tube‘ portions to a single rib
Без категории
Размер файла
662 Кб
Пожаловаться на содержимое документа