IMPROVEMENTS IN STEAM GENERATORS
Year: 1884

page_text: I JAMES BLAKE of the Britannia Works, Newton Heath, Manchester in the
County of Lancaster Boiler Maker, do hereby declare the nature of the said
invention for "IMPROVEMENTS IN STEAM GENERATORS" to be as follows :-
My invention relates principally to part of a former invention for which Letters
Patent bearing date the twenty-fourth day of December in the year 1878 and
numbered 5254 have been granted to me. In the specification of my said former
invention and in particular when referring to Figs. 13 and 14 of the drawings
attached to the said specification I described certain forms of steam generators
having cylindro-spherical or plano-spherical shells. The principal object of my
present invention is to increase the steam space and the steam producing capacity
when taking for comparison generators occupying equal horizontal areas whilst
retaining the constructive advantages possessed by the generators described as
aforesaid. According to my present invention I make the shell in the form of two
hemispheres or portions of spheres connected together by means of a cylindrical
belt the regular formation being broken by the introduction of a flat tube plate
on one side or on each of two opposite sides the furnace opening or openings being
also formed in the same plate. I provide the generator with one, two, three or
more furnaces and in order to be able to attach the front ends of the furnace flues
to the tube plate whilst maintaining a suitable area of cross section in each flue
I contract the furnace mouths either by making them of a conical form or by
making the flues barrel shaped. This contraction of each furnace mouth reduces
the size of the hole to be cut in the tube plate. In order to strengthen the said
plate at this part I prefer to fix a water stay or a suitable stay across the furnace
mouth just below the position for the dead plate. The tube plate by preference
is bent outward above the tubes to join the spherically shaped top. In some cases
I may make the outward bend in the tube plate below the tubes and extend the
latter over the front ends of the furnace flues by preference moulding the tube
plate to unite with the cylindrical belt. In some of the cases wherein there are
two or more furnaces each opens into a separate vertical combustion chamber as
for example in a generator having three furnaces or three on each side the central
furnace is lower than the side furnaces and discharges into a taller combustion
chamber having more tubes extending to the front plate than each side chamber.
To connect the inner end of each furnace flue with its combustion chamber I apply

page_text: a tapering contraction ring which has it's axis inclined so as to make connection
with the inclined bottom of the chamber the products of combustion passing into
the chamber partly in an upward direction. My invention facilitates the con-
struction of steam generators suitable for marine purposes and the obtainment of
Bound workmanship as the furnaces combustion chambers and fire tubes can be
completely riveted up and secured to the tube plate and be inserted bodily into
the shell the connection of the two parts being effected by riveting or bolting the
tube plate to the shell. Where necessary the combustion chambers are subse-
quently stayed to the shell in the usual manner. In another modification of the
spherically formed generator I make the front part of the shell to taper to meet
the circular or nearly circular front plate which is excentrically disposed so that
it is kept low the tapering ring being about horizontal at the bottom.
construction is also applicable to the end or to each end of a cylindrical boiler
and dispenses with some of the staying and also leaves the steam space more clear
from obstruction.
This
The accompanying drawing represents a section of a typical boiler constructed
according to my invention. In the said drawing a is the furnace flue or one of
the flues contracted at the mouth band at the rear end c where it joins the
combustion chamber d. The parts e, c, of the shell are spherically moulded the
band f being of cylindrical formation. The upper end of the tube plate g is bent
forward and upward and connected with the shell.
1007

page_text: Improvements in Steam Generators.
I JAMES BLAKE of the Britannia Works, Newton Heath, Manchester in the
County of Lancaster, Boiler Maker, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN STEAM GENERATORS" and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement and accompanying drawings :-
My Invention relates principally to part of a former Invention for which Letters
Patent bearing date the twenty-fourth day of December in the Year 1878 and:
numbered 5254 have been granted to me. In the Specification of my said former
Invention and in particular when referring to Figs. 13 and 14 of the drawings
attached to the said specification I described certain forms of steam generators
having cylindro-spberical or plano-spherical shells. The principal object of my
present invention is to increase the steam space and the steam producing capacity
when taking for comparison generators occupying equal horizontal areas whilst
retaining the constructive advantages possessed by the generators described as
aforesaid. According to my present invention I make the shell in the form of two
hemispheres or portions of spheres connected together by means of a cylindrical
belt the regular formation being broken by the introduction of a flat tube plate on
one side or on each of two opposite sides the furnace opening or openings being also
formed in the same plate. I provide the generator with one, two, three or more.
furnaces and in order to be able to attach the front ends of the furnace flues to the
tube plate whilst maintaining a suitable area of cross section in each flue I contract
the furnace mouths. In some of the cases wherein there are two or more furnaces
each opens into a separate vertical combustion chamber. In a modification of the
spherically formed generator I make the front part of the shell to taper to meet the
circular or nearly circular front plate which is excentrically disposed so that it is
kept low the tapering ring being about horizontal at the botton. This construction
is also applicable to the end or to each end of a cylindrical boiler and dispenses
with some of the staying and also leaves the steam space more clear from
obstruction.
In order that my Invention may be well understood I will describe the saine
with reference to the accompanying drawings wherein Fig. 1 represents a vertical
section of a Marine boiler constructed in accordance with my Invention Fig. 2
being a front sectional elevation of the same the left hand part of the Fig. repre-
senting a section on the line A. B. in Fig. 1. The section of Fig. 1 is supposed to
be taken through the centre of the middle furnace. In this example the upper and
lower portions of the outer shell of the boiler are composed of spherically moulded
plates a. a. which are united by a cylindrical belt b. At the front of the boiler the
spherical and cylindrical portions unite with a flat tube plate which is inclined
outward at its upper end c¹ so as to meet the spherical crown at a lower point than
if the plate was continued upward on the same plane as the lower part. This
formation furnishes increased steam space and also increases the strongth of the
upper end of the plate. If preferred the plate may be continued upward in the

page_text: same plane or the plate supporting the furnace flues may be bent outward at
a point below the tubes so as to join and support the tube plate which under these
circumstances would be brought forward so as to be flush with the circumference
of the boiler as indicated by the dotted lines in Fig. 1 and by the smaller plan view
Fig. 1. By this construction the length of the tubes is increased. When the tube
plate is thus brought forward cross stays x. are introduced as shown in dotted lines
in Fig. 1. The generator is formed with three furnaces a central furnace d and two
side furnaces e. e. and each furnace opens at its rear end into a separate combustion
chamber f. To suit the half spherical form of the bottom of the generator the two
side furnaces are at a higher level than the centre furnace. The front end of each
furnace is constructed in a similar manner to the mouth of a jar and is riveted to
the tube plate which is flanged inward to meet the furnace mouth. In the cases of
the two side furnaces the contracted mouths are excentric with relation to the
furnace shell as indicated in Fig. 2. This contraction of the furnace mouth and
the excentric formation in the cases of the side furnaces enable me to provide
suitable furnace room whilst keeping the furnace as low down as possible and also
reduces the sizes of the holes cut in the tube plates. In some cases I may cone or
otherwise contract the mouths of the furnaces and when desirable I also contract
the rear end of the furnace at its junction with the combustion chamber. The back
plates of each combustion chamber are spherically moulded or are curved or moulded
to suit the formation of the outer shell and are connected therewith by means of
stays g.
My Invention facilitates the construction of steam generators suitable for marine
purposes and the obtainment of sound workmanship as the furnaces, combustion
chambers and fire tubes can be completely riveted up and secured to the tube
plate and be inserted bodily into the shell the connection of the two parts being
effected by riveting or bolting the tube plate to the shell. The diagram Fig. 3
illustrates a double ended boiler or a boiler constructed to be fired from both sides.
In this example two tube plates c¹ c¹ one on each side of the boiler are mounted
with the spherically and cylindrically formed portions of the outer shell. The
upper end of each tube plate is bent outward at about right angles so as to still
further increase the steam space. Such a formation may be adopted in the
construction of the first described generator. The inner ends of the furnace flues
are connected with the combustion chambers f¹ by means of a tapering contraction
ring e¹ which has its axis inclined so that it can be united by one end with the
furnace flue and by the other end with the inclined bottom of the combustion
chamber. This formation increases the length of the furnace and improves the
draught as the products of combustion flow in an inclined upward direction into
the chamber. The mouths of the furnace are contracted by curving the shells
inward and a water tube stay h. is fixed across the furnace mouth at a point just
below the dead plate. Such stays may be applied in any of the generators
constructed in accordance with my invention. The diagram Fig. 4 illustrates a
modification which may be made in the form of either single or double fired
generators. In this example the top and bottom portions of the shells are made
to be a little more than hemispheres in formation and the central cylindrical belt
is suitably flanged out at both ends to unite with the spherically moulded plates.
In the drawing a barrel shaped furnace is indicated by dotted lines. Such a
formation of furnace may be adopted in any case when carrying my Invention
into effect. Fig. 5 illustrates the construction of generators formed with excen-
trically disposed circular tube plates. In the example a generator of horizontal
cylindrical type has been selected for illustration. The tube plate i. is of a circular
form having a diameter less than that of the cylindrical shell k. The centre of the
circle of the plate is below the axis of the cylindrical shell as indicated by the
diagram Fig. 6. The tube plate is connected with the shell k. by means of a ring 7.
which at one end unites with the said shell and is tapered or contracted so as to be
united by the other end with the tube plate. This taper of the shell varies from
nothing at the bottom to a comparatively considerable amount at the top owing to

page_text: the excentrical position of the tube plate. This formation dispenses with some of
the staying for the upper parts of the tube plate and leaves the steam space more
free from obstruction. It will also be seen that the formation facilitates the
application of the up-take m.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
1. The steam generators formed and constructed substantially as set forth and
indicated herein before and by Figs. 1 and 2 of the drawings.
2. The steam generators having the upper and lower parts formed of spherically
moulded plates and united together by means of cylindrically shaped belts or
plates and flat tube plates substantially as and for the purpose set forth and
indicated.
3. The steam generator of the formation substantially as set forth and indicated
with reference to Fig. 5 of the drawings.