Improvements in or relating to Steam Generators and Cannon.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Steam Generators and Cannon.
A communication from GEORGE H. REYNOLDS, of the City and County of New
York, in the State of New York, United States of America.
1 ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
The invention is intended to supply a safe and convenient means of generating and
preserving dry steam under high pressure without priming under sudden demand for
steam. The nature of the improvement and the means of carrying out the invention
are described herein with reference to the accompanying drawings of which
Fig. is a vertical longitudinal section of a stationary steam generator constructed
in accordance with this invention.
Fig. 2 is a vertical cross section of the same made in the line of Fig. 1 and
as seen when looking toward the firebox.
Fig. 3 is a side elevation of a pneumatic gun with a hollow pintle provided with
air passages and having both ends closed and furnished with valve mechanism for
admitting compressed air or other gaseous medium or vaporous body at high tension
into the space within the discharge valve casing, a discharge valve technically called
a firing valve, mechanism for operating the firing valve, means for elevating and
training the gun and other features of construction patented to my correspondent
in four Letters Patent of the United States all dated February 11, 1890 and
numbered as follows:-No. 421306; No. 421308; No. 421311, and No. 421312,
this Figure being introduced with modifications which illustrate the application of
high-pressure steam to the throwing of projectiles and also some features of the
present invention hereinafter described.
Fig. 4 is an enlarged sectional plan of a portion of the rear part of the gun and its
mechanism also showing features of the present invention.
Figs. 5 and 6 are respectively sectional side elevation and a plan view of a
a field of
portable form of the improved steam generator adapted to use on
battle.
The invention is designed to afford a means not only for generating steam at
a very high pressure for use in throwing projectiles (either shot or shell charged
with dynamite or other analogous explosive) but also to generate it in such a way as
to insure perfect dryness in the steam confined for said purpose and also to prevent
sudden diminution of pressure when discharging the gun from causing jumping,
foaming or priming of the water from which steam is generated.
A Fig. 1, is a shell of steel or other metal of sufficient tensile strength and
thickness to carry and sustain with a large factor of safety a very high interior
pressure for example say one thousand and fifty pounds per square inch. The
interior of this shell is supplied with water up to the level of the line W W which
is approximately the intended water-line; and from this water the high pressure
steam is generated by the heat of gaseous products pro luced from combustion of
suitable fuel, coal, wool, mineral oil, natural gas or other available combustible in
a furnace B. Coal being generally the most available, the furnace is shown as
constructed for this fuel. But the furnace may be otherwise constructed and its parts
immediately to be described, may be widely varied without in any manner varying the
principles or the substantial operation of this invention.
In this furnace a is the grate the fire-door, c the ash-pit door, d the combustion
chamber, e the ash-pit, the direct smoke pipe, a pipe or flue for conveying
the gases of combustion to and applying them to the shell A of the generator as

page_text: hereinafter more fully described and h an uptake or flue for conveying the smoke to the
smoke pipe after the heat has been applied to the shell A. The smoke pipe f, flue g,
and uptake h are respectively supplied with dampers kkk".
To protect the flue g from the chilling effect of winds it is enclosed in an air
chamber C, which may be lined with any suitable non-conducting material 1. A door.
whereby access to the inside of the chamber may be had is shown at m.
The combustion chamber d is preferably lined with fire-brick n.
When kindling a fire in the furnace or when it is not desired to make steam the
dampers and may be closed and the draught regulated by opening or closing
the damper k.
The shell A which I shall hereinafter style the boiler is enclosed in a casing D
which for the stationary generator may be all of brick-work but which I prefer to
construct of, first pavement of hard-burned brick p extending also under the ash-pit
and if desirable far enough in front of the furnace to form an ample hearth,
second, of a boiler-iron arched case 9 resting upon the pavement and a cylindrical
lining of fire-bricks. The angles between the course of fire-bricks the pavement.
and boiler iron casing at the bottom, may be filled in with common hard-burned bricks
as shown at s in Fig. 2.
The casing D is joined at t by riveting or bolting with the casing E of the air
chamber C the latter casing being also of boiler-iron arched as shown, and joined to
the casing of the furnace at t¹ by riveting or bolting.
The shell of the furnace B is also of boiler-iron and in the stationary generator is
preferably square in plan though it may be circular if desired.
The boiler is fed with water by a pump F the induction pipe for water being shown
at and the pipe which feeds the boiler being shown at u.
When it is desired to make steam in A the damper k is closed the damper is
opened and the draught is regulated to meet the demand for steam by the use of
the damper A. The pipe 9 connects the upper part of the combustion chamber
with the annular space gi under the boiler A. This space is separated into upper
and under passages by plates g" one on each side of the boiler extending from
the air chamber C to a distance from the end of the boiler that leaves an ample
The
opening between said upper and under spaces for the passage of the gases.
heated products of combustion circulate, when the boiler is making steam as shown
by the arrows.
The outlet pipe for steam from the boiler is shown at G. A water column with
try-cocks is attached to the boiler as shown at H in Fig. 2, and a steam-gauge may
also be attached to the boiler if desired.
To insure that the steam produced shall be always dry when conveyed to the
gun and also to prevent the jumping, foaming or priming of the water in the
boiler by sudden reduction of pressure when the gun is discharged, I use a steam-
chamber to which while it is liable to a sudden reduction of pressure the steam from
the boiler is fed slowly but continuously till its maximum pressure is reached; and I
place this steam chamber in the steam space of the boiler and place in the pipe G
which is the eduction passage from the boiler leading to the steam chamber a
pressure-reducing valve whereby the pressure is always kept somewhat less in the
steam chamber than in the boiler. By reason of the fact that this steam chamber is
situated in the steam-space of the boiler it takes the temperature of said steam-
space and as its contained steam is maintained at a lower pressure than that in the
boiler, it has a temperature higher than that of saturated steam at the same pressure
and is thus superheated to an amount corresponding to and strictly correlated with
such difference in pressure. For example, if the pressure in the boiler be one
-thousand-and-fifty pounds per square. inch, and that in the steam chamber be one
thousand pounds the steam in the steam chamber will be superheated to an amount
corresponding to and correlated with the difference in pressure-fifty pounds.
Consequently the steam in the steam chamber will be perfectly dry. By adjustment
of the pressure regulating valve this difference of pressure can be regulated to
superheat the steam prior to the use of the latter for the discharge of the projectile

page_text: to any desired amount so that when it expands behind the projectile it will still
remain dry.
By connecting a safety valve with the steam chamber set to blow off at the
maximum pressure in said steam chamber any water that may be forced over into
said chamber or which may be condensed therein when the apparatus is allowed to
cool will when the boiler is again heated, be converted into saturated steam whereupon
any surplus of steam tending to raise the pressure above the regulated maximum
pressure will blow off through the safety-valve and the remainder will then become
superheated.
I use such a safety valve in this present invention and so connect it with the steam
chamber that it relieves from undue pressure not only the steam chamber but also the
boiler thus insuring the safety of both. All these features I will now describe in
detail.
I is the steam chamber. It is made of very heavy strong metal sufficiently stiff to
resist the exterior collapsing pressure in case it should be suddenly emptied of steam
through any disarrangement of the valve which controls its escape. "To this end it
may be strengthened with interior struts. or braces to any extent but as the intro-
duction of these in the drawings would be confusing they have been omitted, the shell
of the steam chamber for purposes of this description being assumed to be thick and
strong enough to support safely the maximum exterior pressure to which it might be
submitted by the sudden total escape of its contained steam.
There are many ways of constructing such a chainber and inserting it into the
steam space of the boiler A which will suggest themselves to skilled boiler-makers. I
will therefore describe only one way in which it can be done premising however that
this invention is entirely independent of any particular construction of the boiler or
steam chamber. Such construction may be widely varied without in any way
affecting the principles or the substantial operation of this invention.
The steam chamber shown is made of sheet steel either strongly riveted and caulked
in the usual manner or welded and either of a thickness to resist any collapsing
pressure which is liable to come upon it or interiorly braced to strengthen it as above
set forth. It has a flanged head K and an extension L. To the extension L is
attached by riveting or welding a flange a fitted to a flange a on the boiler A these
flanges being preferably held together by bolts with suitable interposed packing,
though they may be if desired, riveted together and caulked in the usual manner.
The
The inner extremity of the steam chamber is supported by a saddle.
extension protrudes from the boiler A. It has a flanged head to which is
also attached a pipe M which when a pneumatic gun of the construction described in
the patents hereinbefore enumerated is used, leads to and connects with the interior of
the hollow pintle N as shown in Fig. 3. The passage in this pipe is continuous with
passages (Fig. 4) in the trunnions and O leading backward from the trunnions to
the valve mechanism also described in the aforesaid patents. This valve mechanism [
have not considered necessary to describe in detail here as it forms no part of the
present invention, and any other suitable valve mechanism may be used.
other suitable way of connecting the pipe M with a space behind the projectile in the
gun the induction of steam to which is controlled by a valve or valve mechanism of
any suitable description whatever may be used without affecting either the principles
or the operation of this present invention. My correspondent has therefore patented
only in the form of a diagram the valve mechanism patented to him in United States
Letters Patent No. 421306 above cited, which is lettered P in Fig. 3. This valve
mechanism holds the steam back in the pipe M or admits steam to the space P' at the
rear of the projectile according as it is controlled by its lever b².
Also any
The space P¹ also shows a diagram of the projectile retarder patented to my
correspondent in Letters Patent of the United States, dated February 11th, 1890, and
numbered 421307. This retarder is as desirable to use when steam is employed as
when air or an explosive charge is used to throw a projectile; but it forms no part of
the present invention.
The valve P being closed, the steam chamber I and the pipe M will fill with steam

page_text: as hereinafter explained, whenever steam is generated in the boiler at a pressure
exceeding the prearranged difference in pressures in the interiors of the boiler an
the steam chamber which difference is secured by a pressure regulating valve, shown
at Q in Fig. 1. This valve may be of any approved kind in the market that 15
capable of adjustment to regulate the difference of pressure maintained between the
space above and that below its seat. I have typically represented it as a disc-valve e¹
having a stem e² with a step on the end which is engaged by a spring c³ that acis
between the bonnet R and the step to press the valve c' down upon its seat. This disc
is for clearness shown in the drawing in exaggerated proportions. It is in reality a
very small wire-drawing valve, that only permits steam to flow slowly from the
boiler A into the steam chamber I. It has ample time, notwithstanding its small
size, to restore the pressure in the steam chamber in the intervals between successive
discharges of the gun. Steam issuing from the boiler through the pipe G must over-
come the back pressure of the steam on the upper side of the disc c; plus the pressure
exerted by the spring, the strength of which will therefore represent the difference in
the steam pressures on opposite sides of the disc. The difference may therefore
always be prearranged by placing in the valve-case a spring of the requisite power.
From the valve-case above the valve-disc d' extends a pipe or passage S S¹ to the
extension 1 of the steam chamber 1. Through this passage steam enters said steam
chamber.
Also at the junction of S and S, or at any other convenient point in the passage SS',
is attached a safety-valve T, which not only limits the pressure that can be carried in
the steam chamber, but also determines the limit of pressure in the boiler, the latter
being as already explained, the same as that in the steam chamber plus that determined
by the strength of the spring.
The construction of the portable form of the generator is substantially the same as
in the stationary form. The modifications consist as shown in Figs. 5 and 6 in making
the furnace and the outer shell D cylindrical, joining the latter directly to the furnace
and supplying front and rear wheels with the ordinary fifth-wheel mechanism V
and a pole VI
ט
The bearings of the rear wheels may be attached directly to the furnace. The
front wheels are attaclied to an axle and the fifth-wheel V is connected by an iron
frame V to the shell D. It results from the great pressure exerted in throwing heavy
projectiles, and the high temperature of the steam, that the metal of the gun becomes
heated. In throwing dynamite shells this heat is liable to cause exudation of the
nitro-glycerine out of the granular material with which it is mixed into the bore of
the gun which, if prevented, might prove dangerous. To remove this liability and
also recover a portion of the heat which would otherwise be wasted and make this heat
auxiliary to the generation of more steam, the feed-water is caused to pass over the
metal of the gun and near the breech before putting into the boiler. Thus the gun is
cooled while the water is partially heated.
To carry out this part of the invention a hollow annular space or jacket is formed
around the barrel of the gun as shown at j Figs. 3 and 4. It is preferred to make
the shell of this jacket corrugated, as shown, so that it may yield as the interior metal
contracts or expands by heat and thus escape injurious strains; but however the jacket
may be constructed it is a continuation of the water passage which supplies water to
the boiler. The pump produces Ly its action a reduction of pressure in the pipe u
and this reduction of pressure extends to the jacket j, and to the pipe through which
water is drawn to supply the boiler without subjecting the jacket to any internal
pressure above that of the atmosphere, the feed pump being placed between the jacket
and the boiler. If the pump were otherwise placed so that the jacket would lie
between the pump and the boiler, it would be subjected to the same pressure as the
interior of the boiler, and consequently to as great a rupturing strain as the interior
of the gun receives, to resist which the jacket would need-to-be made- very heavy, and
cum brous. As my correspondent has constructed and arranged parts, the jacket' can
be made light and thin so that it need not make a notable and objectionable
enlargement

page_text: The pipes u u' and u are referred to by these letters for convenience only, but they
together with the jacket j and the passages in the feed pump form a continuous.
passage, which for brevity will hereinafter be styled the feed-pipe of the generator.
These pipes are led to points near the trunnions of the gun and there connected by
pipes with flexible joints or lengths of hose rearward to the jacket, in order not to
interfere with the elevation or the training of the gun.
The purpose of the protruding extension of the steam chamber is to bring all the
parts and joints of the valves pipes etc., which may need attention into easily accessible
positions.
When a sudden demand for steam is made upon the dry and superheated steam in
the steam chamber as in discharging the projectile, steam from the boiler begins
to flow quietly through the pipe G into the steam chamber until the pressure is.
gradually restored therein and the steam again, dried and prepared for a subsequent
discharge.
Very good advantages result from the use of steam as a substitute for air in the
throwing of projectiles. The air compression apparatus is rendered needless and as
confined steam issues from an orifice with much higher velocity than air at the same
pressure, a much higher initial velocity and consequently a much greater range of the
projectile is secured.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. In combination with a gun for throwing projectiles a steam generator consisting
of a boiler, a water feed pipe, an eduction pipe for steam, a valve connected with the
eduction pipe for regulating the flow of steam, a steam chamber enclosed in the boiler
having its steam space connected only by the said eduction-pipe with the steam-space-
of the boiler but also having its steam-space connected with a discharge-pipe or
passage for conveying dry steam to the gun, discharge-valve mechanism for controlling
the discharge of steam in operating such guns and a furnace for supplying heat
to the boiler; substantially as herein described and for the purposes set forth.
2. In combination with a gun for throwing projectiles a steam generator consisting
of a boiler, a water feed pipe, an eduction-pipe for steam, a valve connected with the
eduction-pipe for regulating the flow of steam, a steam-chamber placed in the steam-
space of the boiler, the steam-space of the steam-chamber being connected with tho
steam-space of the boiler only by the said eduction-pipe but being also connected
with a discharge pipe or passage for conveying dry steam to the gun, discharge.
valve mechanism for controlling the discharge of the steam in operating such gun and
a furnace for supplying heat to the boiler; substantially as and for the purposes
herein described.
3. In combination with a gun for throwing projectiles, a steam generator consisting
of a boiler, a water-feed pipe, an eduction-pipe for steam, a pressure-reducing valve
connected with the eduction-pipe for regulating the flow of steam and maintaining a
prearranged difference in pressure between the steam-space of the boiler and the
steam-space of the steam-chamber, a steam-chamber inclosed in the boiler having its
steam-space connected only by the said eduction-pipe with the steam-space of the boiler
but also having its steam-space connected with a discharge-pipe or passage for
conveying dry steam to the gun, discharge-valve mechanism for controlling the
discharge of the steam in operating such gun, and a furnace for supplying heat to
the boiler substantially as described and for the purposes set forth.
4. The combination with the gun, the boiler having a water-feed-pipe, an eduction-
pipe for steam which is also an induction-pipe, to a steam chamber within the boiler,
a pressure-regulating valve connected with the eduction-pipe for regulating the flow
of steam into the steam-chamber and reducing its pressure, a steam-chamber for
superheating the steam enclosed in the boiler having its steam-space connected only by
the eduction-pipe with the steam-space of the boiler but also having the steam-space

page_text: "
connected with a discharge-pipe or passage for conveying dry steam to the gun,
discharge-valve mechanism for controlling the discharge of steam in operating such.
gun, and a furnace for applying heat to the boiler, of a safety-valve connected with
the eduction-pipe or passage of the boiler between the pressure-reducing valve and
the opening of said pipe or passage and steam chamber whereby the pressure being
relieved at a certain maximum in the steam chamber the pressure in the boiler will
be simultaneously relieved by the action of the pressure-reducing valve; substantially
as herein described and for the purposes set forth.
'
5. The combination with a steam-generator constructed and connected substantially
as described, having a boiler containing a steam-chamber, a pipe connecting the
steam-space in the boiler with the steam-space in the steam-chamber, a valve for con-
trolling the flow of steam from the boiler into the steam-chamber, a discharge-pipe
connected with the steam-chamber, a water-feed-pipe for the boiler and a furnace B
for combustion of fuel, of a casing D divided by plates g" into spaces forming a
continuous flue under and over the boiler, a flue g connecting the combustion chamber
of the furnace with the space under the boiler, and an uptake for the spent gases or
ammoke; substantially as described.
6. The combination with a steam generator constructed and connected substantially
as described having a boiler containing a steam-chamber, a pipe connecting the steam-
space in the boiler with the steam-space in the steam-chamber, a valve for regulating
the flow of steam from the boiler into the steam-chainber, a discharge-pipe connected
with the steam-chamber, a water-feed-pipe for the boiler, a furnace B for supplying
heat to the boiler, a casing D containing a flue for the passage of heated products
of combustion under and over the boiler, an uptake for escape of the spent gases, and a
flue y, connecting the combustion chamber of the furnace with the flues in the casing,
of an air-chamber G, which prevents loss of heat from the flue g and permits access to
said flue and to the flues in the casing D for the purposes of cleaning or repairs ;
substantially as herein described.
7. The combination of the boiler and its contained steam-chamber, the eduction-
pipe of the boiler constituting also the induction pipe, of the steam-chamber, the
valves and the fittings in and connected with said pipe, and the extension L connected
with the discharge-pipe M, the said pipe, valves, fittings and extension being all
exterior to the boiler, whereby the connections are all made easily accessible from the
exterior of the generator; substantially as described.
8. The combination with the boiler and its contained steam-chamber, the eduction-
pipe of the boiler constituting also the induction-pipe of the steam-chamber, the
valves and fittings in and connected with said boiler, steam-chamber and eduction-
pipe, the extension L and its discharge-pipe M, the furnace B, the casing D, the air-
chamber U, the uptake leading from the casing D to the smoke-pipe and the flue g
connecting the combustion chamber with the flue space in said casing, of running
gear consisting of rear carriage wheels attached to the furnace, from carriage
wheels attached to the casing D, and provided with an axle, fifth wheel and pole
whereby the generator is rendered portable for use on a field of battle substantially
as described.
9. The combination with a gun for throwing projectiles and the water-feed-pipe,
of a steam generator for supplying steam to the gun, of a water jacket surrounding
the back part of the gun, and having its interior continuous with the interior of
the said pipe for extracting heat from the gun and imparting the heat so
extracted to the water passage through the said pipe and jacket on its way to the
interior of the steam generator; substantially as herein set forth and for the
purposes described.
10. The combination with a gun for throwing projectiles and the water feed pipe
for supplying water to a steam generator which supplies steam at high pressure to
the gun, of a water jacket which surrounds the back part of the gun and has its
interior continuous with the interior of said feed pipe for extracting heat from the
gun and imparting it to the water during the passage-of-the-water to the generator

page_text: and a feed pump connected on its discharge side with the generator and having its
suction valve chamber connected with said jacket whereby the water is subjected to
pressure greater than that of the atmosphere only after it passes through the jacket
and enters the pump; substantially as berein described.
Dated this 4th day of June 1890.
W. P. THOMPSON & BOULT,
Agents for the Applicant.