Improvements in and connected with Steam Bollers.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in and connected with Steam Bollers.
I, Sir CHARLES STEWART FORBES, Baronet, of Castle Newe, Strathdon, Aber-
deenshire, Gentleman, do hereby declare the nature of this invention to be as
follows:-
-
My invention relates to a special construction of light steam generator and in
improved means and apparatus for firing the same.
It is carried out as follows:
Upon a metallic base 1 secure by screws bolts, or the like, a double jacket formed
of sheet, or cast iron or steel and preferably made in segments, the edges of the
segments being faced and bolted or otherwise fitted together. This jacket may
be packed with asbestos, magnesia or like non conductor of heat, or air may be
permitted to pass through it. To the top of the inner jacket is secured by bolts
or the like a throat preferably of cast iron, or steel having a central orifice which
serves as an outlet to the chimney: a series of pockets being formed in the outer
skin. To the throat is bolted a receiver which is formed of steel copper, iron, or
any suitable metal, this receiver is preferably of T shape but it may take any
other convenient torm which will fulfil the conditions of my invention.
The central portion of the receiver is formed or fitted with a tube in continua-
tion of that in the throat this tube being cast with, riveted or otherwise fastened
at its base to a plute, which is boited or otherwise fastened to the upper flange
of the throat and riveted at its top end to the upper part of the receiver, or in
some cases the upper end of the tube may be passed through a gland so as to
be readily removed. The top end of the central flue is in any case fitted with a
chimney or cowl of suitable height. Into the annular space between the smoke
flue and the body of the receiver, are screwed, riveted, or expanded, a series of
short metal tubes fitted with union nuts, the length of these tubes being 50
arranged as that the nuts shall occupy a position in such pocket suitable for
screwing up by means of a spanner or the like.
These unions serve to connect a series of tubes formed, of copper, steel, iron, or
other suitable metal which are spun into coils or they may take any other suitable
shape for obtaining the best effects of heat. The end of each separate coil or tube
passes through the grate bars and is then turned up outside the jacket and con-
nected preferably by unions to short pieces of tube screwed or expanded into the
covers of the T shaped ends of the receiver, or in case of a cylindrical or rectan-
gular receiver into a suitable position in the sides.
The objects I have in view in the particular construction described being, first,
to obtain rapid circulation by compelling the water to flow from the extreme
onds or coolest part of the boiler downward, and upward through the grate and
hont of the fire.

page_text: Secondly to enable the respective parts of both boiler and furnace to be readily
taken to piece for renewal or repairs. For firing I may use either coal, coke, or
other fuel, or I may employ a series of annular shaped vapourizers each of which
is by preference cast in one piece of metal, thereby saving all joints and avoiding
leakage. These may be so mounted up and connected as that steam taken from
the boiler, or the exhaust steam from an engine shall pass through the inner
tube for the purpose of creating a draught and breaking up and thereby rendering
combustible the hydrocarbon vapour derived from the oil or spirit employed as
fuel.
100%
Improvements in and connected with Steam Boilers.
I, Sir CHARLES STEWART FORBES, Baronet, of Castle Newe, Strathdon, Aber-
deenshire, Gentleman, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement:-
My invention relates to a special construction of light steam generator and in
improved means and apparatus for firing the same. It is carried out as follows:
Upon a metallic base I secure by screws, bolts or the like a double jacket formed
of sheet, or cast iron or steel and preferably made in segments, the edges of the
segments being faced and bolted or otherwise fitted together. This jacket may
be packed with asbestos, magnesia or like non-conductor of heat, or air may be
permitted to pass through it. To the top of the inner jacket is secured by bolts
or the like, a throat, preferably of cast iron or steel, having a central orifice which
serves as an outlet to the chimney; a series of pockets being formed in the outer
skin. To the throat is bolted a receiver which is formed of steel, copper, iron, or
any suitable metal; this receiver is preferably of T shape, but it may take any
other convenient form which will fulfil the conditions of my invention.
The central portion of the receiver is formed or fitted with a tube in continua-
tion of that in the throat, this tube being cast with riveted, or otherwise fastened
at its base to a plato which is bolted or otherwise fastened to the upper flange
of the throat, and riveted at its top end to the upper part of the receiver, or in
some cases the upper end of the tube may be passed through a gland so as to
be readily removed. The top end of the central flue is in any case fitted with n
chimney or cowl of suitable height. Into the annular spaco between the smoke
flue and the body of the receiver are screwed riveted or expanded a series of
short metal tubes fitted with union nuts, the length of these tubes being so
arranged as that the nuts shall occupy a position in such pocket suitable for
screwing up by means of a spanner or the like.
These unions serve to connect a series of tubes formed of copper, steel, iron or
other suitable metal which are spun into coils, or they may take any other suitable
shape for obtaining the best effects of heat. The end of each separate coil or tube
passes through the grate bars and is then turned up outside the jacket and con-
nected preferably by unions to short pieces of tube screwed or expanded into the
covers of the shaped ends of the receiver, or in case of a cylindrical or rectan-
gular receiver into a suitable position in the sides. The objects I have in view
in the particular construction described being, first to obtain rapid circulation

page_text: by compelling the water to flow from the extreme ends or coolest part of the
boiler downward, and upward through the grate and heat of the fire; secondly,
to enable the respective parts of both boiler and furnace to be readily taken to
pieces for renewal or repairs. For firing I may either use coal, coke or other fuel, or
may employ a series of annular shaped vapourizers, each of which is be pre-
ference cast in one piece of metal, thereby saving all joints and avoiding leakage.
These may be so mounted up and connected as that steam taken from the boiler,
or the exhaust steam from an engine shall pass through the inner tube for the
purpose of creating a draft and breaking up and thereby rendering combustible
the hydrocarbon vapour derived from the oil or spirit employed as fuel.
To enable my invention to be better understood I will proceed to explain the
same by means of the accompanying drawings, in which:
Fig. 1, Is a part vertical section.
Fig. 2, Is a sectional half-plan taken on line A B. Fig. 1.
Fig. 3, Is a sectional plan of throat on line C D. Fig. 1.
Fig. 4, Is a part sectional view shewing removable smoke tube.
Fig. 4, Is a section shewing smoke tube riveted to receiver.
In the drawings 1, is the base, which is usually formed of cast iron. To this
is secured by screws, bolts or rivets 2, a double jacket preferably
formed by means of 4, or in the case of large boilers more than 4,
cast steel or iron segments 3, united by flanges or ribs 4, which after being
tooled or faced are bolted together in the manner shewn in Fig. 2. Around the
ribs is bent a thin skin of steel or iron plate 5, to which it is fastened by studs or
screws 2; the void space thus formed may be packed with asbestos, magnesia or
other suitable non-conductor of heat 6, or it may be left quite open, air being
admitted through holes 6°, cast or drilled in the base plate. To the top flange
of the inner segmental jacket 3, is secured by bolts 2, a throat 7, of peculiar
construction, this usually consists of a mild steel or iron casting having a central
opening or orifice 8, which serves as a flue or outlet to the chimney 9. The
annular space between the walls 10, 10', being divided up into a series of pockets 11,
by means of the radial ribs 12. The base 121 and sides 12", being cored out as
shewn. To the faced upper flange 7, of the throat 7, is fastened by bolts 2, a
receiver 13, this I may form of mild steel, copper admixed with sufficient tin or
zinc, to ensure soundness, brass or gunmetal as casting as shewn in Fig. 1, or
it may be welded or riveted up in iron or steel, or brazed up in copper. It is
conveniently made of the T shape shewn, the two outside bends 14, being fitted
with flauges 14', stiffened with gussets 15. When cast a central orifice or flue 8
is formed by coring in continuation of that passing through the throat 7. The
chimney which is formed of sheet iron or steel being secured by screws or bolts 2,
to a faced seating 16, upon the top side. When the receiver is riveted or brazed
up the smoke tube or flue 8, may be cast with riveted, or otherwise fastened at its
base to a plate 9*, bolted to the flange 7 of the throat, its top end being riveted
by an angle ring or equivalent 9, to the upper part of the receiver or if the
tube is liable to be burnt out, it may with a view to easy replacement, pass through
a gland or stuffing-box 9°, see Figs. 4, 4*.
Into the annular space between the smoke flue and the central portion of the
body of the receiver are screwed expanded or riveted, depending upon the con-
struction, a series of short metal tubes 17, having union nuts 18, so arranged
as to be easily screwed up or released by means of a spanner passed through the
openings 12, from the series of tubes 19, which lower down within the inner
jacket, are spun into coils or such other shapes as may best suit the particular
constructional conditions in any case, and the liquid or other fuel employed,
I prefer that these tubes should be solid drawn from steel, copper or suitable alloy
and that thoy should in the case of a segmental jacket of the contour shewn tako
a conical shape. The straight end of each tubular coil passes downwardly through
the segmental grate bars 20, being steadied by means of the hole 20', cored, filed
or otherwise formed between the segments. A union 18, couples the lower end

page_text: of each tube 19, with a dopending tube 19, connected by a union joint 18, with
the short plugs 17, screwed, expanded or otherwise fastened into the covers 14",
bolted to the flanges as shown: a back pressure valve 21, may conveniently be
attached to one of the depending tubes, and to this the feed water pipe 22, is
coupled. A light steam dome may be bolted to one of the flanged connections 23,
and provided with a starting cock and a safety valve may be attached to the
other 23¹.
Two gauge or blow-off cocks and a water gauge glass are attached to the
paps 24, 24. The openings 12 at the base of the throat. 7, are after the pipes
are inserted plugged up with fire-clay 25, or like fire-resisting medium, which
effectually protects from Blume or undue heat the union pipe joints. To stiffen
and support the over-hanging bends I employ by preference a steel rod 26, stepped
into paps 27, on the base plate, and covers 14", or this may be replaced if required
by a light strut or stay cast or built up in wrought iron.
I may use as fuel Coal, Coke, breeze or other suitable solid fuel, or I may use
liquid fuel, in which case vapourizers of the annular type by preference cast in
one piece or made with as few parts or screwed joints as possible, to avoid leakage,
may be employed. Such burners may be mounted up in a ring or otherwise in
a suitable position under the coils or other convolutions of the tubes, and so con-
nected as that live or exhaust steam shall pass through the inner tube for the
purpose of creating a draught and breaking up and rendering more readily com-
bustible the hydro-carbon vapour. The tubular coils are supported by means of
the brackets 29, fastened to the inner skin of the jacket as shewn, and the fire
is fed or attended to by means of the fire-door 28, formed in the base of the front
segment.
The operation of my invention is as follows:-Water is pumped or forced into
the boiler to a suitable level, the fire ignited and steam raised. Since the T shaped
bends are removed to an appreciable distance from the immediate action of the
flame, a sufficient difference of temperature is created to set up a rapid and con-
tinuous circulation through the dependent lateral tubes 19%, in the direction of
the arrows, with the consequent rapid production of steam. A boiler constructed
as described may on occasion be forced to a very high pressure without risk, and
since all the connections are protected from the direct action of the flame leakage
is avoided.
The particular segmental construction herein described enables the tubes or
the receiver to be removed, cleaned and replaced with the minimum of trouble
and a great saving of labour. The receiver is shewn of cylindrical section. It
may however take a rectangular or other shape, being cast or riveted up as may
be most suitable.
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
clain is:-
1. The combination in or with a steam generator of a T shaped receiver, sup-
ported as shewn, and the tubular coils constructed, mounted, connected and having
the union joints protected as described, with a removable segmental casing or
jacket attached to a bed-plate carrying a grate formed in parts or segments and
perforated or shaped as shewn for the purpose of staying the tubes in the manner
Bet forth.
2. In or with a steam generator constructed as described in Claim 1, the par-
ticular combination and arrangement of the throat having cored pockets luted
with fire-clay or the like, for protecting the upper union joints of the coils from
the direct action of the fire, and side apertures therein for connecting or discon-
necting the unions in the way and manner described.
3. In a steam generator constructed as described the combination of the external
and disconnecting circulating tubes coupled to the T shaped receiver bends,
and the tubular coils supported in the jacket by stays and union joints and by

page_text: means of the stay holes formed between the respective parts of the segmental fire
bars or grate as described.
Dated this 4th day of November 1897.
FRANCIS M. ROGERS,
Agent for Applicant, 21 Finsbury Pavement, London, E.C.