AN IMPROVED STEAM GENERATOR
Year: 1861

page_text: LETTERS PATENT to Thomas Hughes, of Birmingham, in the County of
Warwick, Manager of the Imperial Iron Tube Company, for the Inven-
tion of "AN IMPROVED STEAM GENERATOR."
Sealed the 21st January 1862, and dated the 24th July 1861.
PROVISIONAL SPECIFICATION left by the said Thomas Hughes at the
Office of the Commissioners of Patents, with his Petition, on the 24th
July 1861.
I, THOMAS HUGHES, of Birmingham, in the County of Warwick, Manager
of the Imperial Iron Tube Company, do hereby declare the nature of my
said Invention for "AN IMPROVED STEAM GENERATOR,". to be as follows (that
is to say):-
In giving effect to my Invention, my improved steam generator may be so
constructed as to be placed wholly or partially borizontally, diagonally, or
vertical, as preferred, and will be found applicable as well for marine and
locomotive engines as for stationary engines. But for simplifying the descrip-
tion and defining the various parts of its construction and proportion, I will
describe my Invention as adapted for an upright position for supplying high-
pressure steam to an engine, say, of ten-horse power; the proportions herein-
after given being generally suitable, as determined from my present expe-
rience. I construct a base or bottom plate, say, of cast iron, about three feet

page_text: square and an inch and a quarter thick with a hole in the centre with a raised
rim or flange, into which I fix a strong wrought or cast iron tube, and which
tube may diminish below the plate or otherwise, and conducted away for
receiving the water supply, hereafter to be referred to. This wrought or cast
iron centre tube has four projections, more or less, as desired, and which pro-
jections are formed about three feet up from the base plate, and have waterways
formed through them to the centre tube. And this same arrangement I also
form at the top of the centre tube, which may be about eight feet high, the top
being open and formed with a wide projecting flange for supporting the steam
chest, which must be made of boiler plate in the ordinary way; and I prefer it
to be of a circular dome shape; and from the side or top of which the blow-off
valve may be placed, as also the steam pipe for conveying the steam to the
engine. To the projecting radial waterways projecting out from the main
centre tube-I-apply-coiled-tubes by means-of-a right-and-left-hand-coupling;
these tubes I prefer being of good gas or steam tubes of the description
known as welded iron gas or steam tubes, about two or two and a half inches
in diameter, and from fifteen to eighteen feet long, more or less, bent into an
open coil about ten inches in diameter, and which coiling process contracts
the length to about five feet, which admits of their being connected, as before
stated (from their ends being screwed), by a collar tapped with a right and
left handed screw, one part of the collar screwing over the end of the tube,
and the other over the corresponding radiál projection formed on the centre
tube. About two feet from the base or lower plate I place my furnace bars,
building up the brickwork in such a way as to support them, and which brick-
work I continue up around the spiral tubular coils, leaving sufficient room for
the blaze to ascend and play through, around, and between them, 'as also
up against the bottom of the steam chest, the brickwork extending up high
enough, so as to partially surround the steam chest for about one-fourth or
one-third of its height. At the back or side, just under the steam chest, 'I
prefer forming a bridge that the flame may pass over and descend, and at or
about the part where it enters the regular draft way or flue to the chimney or
stack, I prefer placing a small draft way from the furnace that 'a small flame
may pass through and ignite, and thereby consume the smoke that may
escape over the bridge.
With this description I will assume that the furnace fire is being made up,
and that my apparatus, as herein described, has been filled with water so as to
fill up and rise through the centre and spiral tubes some little way into the
steam chest; and that this condition is to be maintained by the ordinary

page_text: force pump or other means with valves and floats, as may be required to.
maintain and indicate a due and proper supply of water as fast as generated
into steam, and escaping through the engine in its ordinary working,. the
fresh supply of water being heated to economise and facilitate its conversion
into steam. Thus it will be seen from this description that I am enabled to
generate steam more rapidly and with a greatly reduced proportion of coal
than now necessary in generating steam from the best description of steam
boilers now in use; and that the entire cost of my apparatus and furnace
will not cost as much by two-thirds as boilers and furnaces now commonly
constructed, in addition to which the dangers from explosion are greatly
reduced; and if such an apparatus can be exploded, such as the bursting of
one of the coils, a new one may be substituted at a trifling cost.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Hughes in the Great Seal Patent Office on the
24th January 1862.
17.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
HUGHES, of Birmingham, in the County of Warwick, Manager of the Imperial
Iron Tube Company, send greeting.
WHEREAS Her most Excellent. Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of July, in the year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Thomas Hughes, Her special license that I, the said Thomas Hughes, my
exccutors, administrators, and assigns, or such others as I, the said Thomas
Hughes, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "AN IMPROVED STEAM
GENERATOR," upon the condition (amongst others) that I, the said Thomas
Hughes, by an instrument in writing under my hand and seal,. should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said Thomas Hughes, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement (that is to say):
may
In my Provisional Specification I have stated that "my improved steam
generator may be constructed so as to be placed or erected horizontally,
diagonally, or vertical, as preferred," but experience now tells me, that a
vertical position is the best. Nevertheless, occasions may arise where, for the
convenience of situation and the adapting of my improvements to furnaces
and flues or chimneys now erected, that a slightly slanting or diagonal posi-
tion be adopted; but in no case do I purpose realising my improvements
in a horizontal position, whether such steam generators be required for loco-
motive, marine, or stationary engines, as a simple and general modification of
the parts have only to be judiciously carried out to render-my improvements
generally applicable. But for simplifying the descriptions and defining the
various parts, general details, and proportions of my generator, I will proceed
to describe the Drawings hereunto annexed, the general proportions of which
are arranged for supplying steam to a stationary engine, and are made to a
scale of about one inch and a quarter to a foot.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a front elevation; Fig. 2, an irregular vertical section; Fig. 3 a
transverse section taken through the dotted line A, B; and Fig. 4 a transverse
section taken through the dotted line C, D, and in the description of the
details it will be seen that the same parts as they occur in the various views,
are marked with the same letters of reference; but as my improvements are
seen best in Figure 2, I will describe that Figure, referring to the parts as
exhibited in the other views when occasion may require. E, E, is the brick-
work or masonry surrounding and forming the furnace for holding the fire,
but which may be constructed of iron if required, and in that case I prefer it
being made double, so as to leave a space between the outer and inner casing
to contain water, which will afford a double advantage, first, the preventing the
iron next the fire rapidly burning away, and, secondly, the means by which
the water may be heated, before supplying my improved steam generator with
the necessary amount of water to support its exhaustion by being converted
into steam; or the outer case may be made of iron, and the furnace portion
lined with fire-brick. F, F, are the fire-bars, which are brought forward to
rest on the dead-plate G, G, in Figure 1; His a base or foundation of stone,

page_text: iron, or other material, on which the main pipe I, I, is placed, and which pipe
is exhibited in section at top and bottom, the latter part terminating with a
contracted neck and broad flange, for forming a seat to rest on the base H:
In the lower end of the pipe I, the tube J, J, is attached, fitted with a tap,
the use of which will be hereafter referred to. K is a supply pipe, through
which water is supplied or injected into the main pipe I, by the usual appliances
now commonly used, to the height indicated by the dotted line L, L, or there-
about, its height being always indicated by the water guage exhibited in
Figure 1, marked M, by a tube from the lower end of the guage being con-
nected with the main pipe I at or about the small circular hole marked N,
while the small hole marked P, is for receiving a small tube in connection
with the cock, Figure 1, marked O. The main pipe I is so formed at the
front and back, that a projection is provided for supporting the ends of the
fire-bars in connection with it, and around the main pipe I, and resting on the
fire-bars; the tube Q, Q, Q, Q, is placed in the position shown, for keeping
the fire from immediate contact with the pipe I; and in order to keep the
pipe I concentric with this tube, projections are formed on the inside for that
purpose, as will be seen at Fig. 5, which is a top view of the tube Q; R, R, is
the base of the steam chest, of which S is the dome, fitted with a man-hole T,
safety valve U, and steam pipe V; all this is supported on the top of the main
pipe I by the bottom of the part R having a concentric hole in its bottom the
same size as the diameter of the main pipe I, which is fitted with a strong
flange or nut shown in section in this view at a, so that the upper end of the
pipe I may pass through, and be held and made steam-tight by the top 'end'
being tapped and fitted with a screw, also shown in section marked b, and
exhibited in a flat view marked with the same letter at Figure 3. The
chamber R, R, is fitted with a circular row of vertical tubes marked A¹, A¹, etc.,
which are tapped each end, and fitted with nuts or screw's so as to fit and secure.
them steam-tight by holding the top and bottom plate of the part R between
the inner and outer nuts, but which row of vertical tubes may be placed in any
other regular or irregular form. These vertical tubes are exhibited also at
Figure 3, and form the draughtway for the flame and heat to pass away between
the outer casing of the part R, R, and the inside of the part or jacket marked
C, C, in the direction of the arrows to the flue B', B', and which flue is
united with angle iron to the outer casing last described, which forms a jacket
for retaining the heat around the base of the steam chest or part R; the
cover D, D¹, I prefer being made in two or more pieces, and capable of being
removed when desired, for removing any dust or non-combustible particles

page_text: carried up by the force of the draught that would tend to deposit itself at the
bottom of this part, or around the draughtway B', B¹. The cover D', D', is
supported on an outer and inner ledge formed of angle iron, one secured to
the outer case at c, and the other to the steam chest at d. The flue B¹ may
be fitted with a damper as here shown, or other suitable means for opening
and closing. the draughtway. On the main pipe I, two circular rings marked
E, E, are fixed by being shrunk on hot, and which rings are exhibited in a
separate top and edge views at Figs. 6 and 7; these rings have four hollow
projections as-at-e, f, g, h, which are tapped for the purpose of receiving right
and left-handed screws as at i, j, and k, and l, m, and n, in Figure 2, holes
being formed through the main pipe I corresponding to the hollow projections
formed on the rings, by which means the coiled tubes F, G, and H', are
united internally and externally-to-the-main-pipe I; and in order to form a
perfect water-tight joint at the meeting of the ends of the coiled tubes, and
the corresponding radial hollow projections on the rings E¹, E', I prefer placing
between them, a soft copper or metal washer as exhibited in an edge and flat
view at Fig. 8, and shown also in dotted lines at i, j, l, and n, and at the same
parts at Figure 4. The coiled tubes I prefer placing in the diagonal form
here shown, in order that the flame arising from the-fire-shall take a more
tortuous course, as it ascends, licking and passing between and around the
tubes in its passage upwards to the vertical tubular flue ways before described
at A', A¹, etc.; the slanting position of the tubular coils is also exhibited in
a top view at Figure 4, but for small engines and contracted furnaces or fur-
nace room, the coiled tubes, instead of being placed entirely from the centre
main pipe I, one or more tubes may be coiled around the centre pipe, so as
to place the main pipe concentrically within the coil or coils of tubes that may
be preferred, such coiled tubes being connected at top and bottom to the main
pipe I in the way herein described and exhibited; or the coils may be bent
of an irregular oval shape, the poles of one revolution of a coil intersecting
the conjugate of the preceding and following one, but in every instance the
course of the coil must be regularly ascending. I mean by this, that in bending
the tubes, they shall gradually ascend from the bottom to the top, no part of
it being parallel or below a horizontal line, for if such was the case, the par-
ticles of steam as generated would be confined, rather than be allowed to freely
rise and escape to the steam chest.
Having now given a general detailed description, and objects of the parts
in detail, I will suppose that water has been supplied or forced in to the main
pipe I to the proper height, filling of course the tubular coils, and that the

page_text: fire being lit, the effect will be to boil and heat the water so as to generate
steam very rapidly, and which steam as fast as generated will become super-
heated by the heat given out from the tubular flues, as it passes up into tho
decreasing
dome S, to escape as required through the steam pipe V, and thus
the volume of water, and increasing the heating surface, a considerable increase
of superheated steam in a given space of time, and with a greatly reduced
proportion of coal than has hitherto been effected by any means of generating
steam, is produced by this Invention, and from any neglect or inattention
should the water be wholly or partially exhausted, or allowed to escape through
the blow-off tube J which forms its sole use, so as to allow the tubular coils
to become red-hot, no dangerous explosion is to be apprehended, as in the
course of testing my Invention, I have by way of experiment stopped the
supply of water, and allowed the tubular coils to get red-hot; and in that
condition, I have again injected cold water without producing any perceptible
injurious effect; but, for example, I will suppose, that one of the tubular coils
should burst, (and I refer especially to the coils, because I believe from their
proximity to the fire, that they are more likely to yield from long usage than
any other part of my generator), the explosion will be insignificant and non-
destructive, and purely local, remediable by the removal of the defective coil,
and the substitution of a new one at little cost, and at the expense of a trifling
loss of time in its repairing. I have not thought it necessary to elaborate
the description of Figure 1, by describing the angle iron, stay rods, peep-
holes, X, X, X, X, etc., as they are common in connection with brick-built fur-
naces, and need no further description, nor the general construction of the water
guage M, and pressure guage Y, as their general construction is well known
and understood; nor have I considered it necessary to exhibit distinct and
separate Drawings of the applicability of my Invention to the generating of
steam for locomotive or marine engines, as the manufacturers of such engines
well know how to adapt my steam generator to such purposes, the advantages
of which are of the highest importance, more particularly to marine engines,
where the economy of coal to ocean-going steam ships is of the highest import-
ance, as it decreases the cost, and increases the space to be profitably used for
mercantile or other freightage.
Having now given a general description of my Invention, and the manner
in which the same may be carried into effect, I wish it understood that I
do not purpose confining myself to the general details herein described and
exhibited, as the same may be varied without departing from the spirit of my
Invention, as, for instance, the top angle of the part R may be curved, and the

page_text: jacket C¹, C', may be of a semi-spherical shape or otherwise, as preferred; and
in some instances, the draughtway may be formed. under the bottom of the
part R, instead of going through tubes, and escaping at the top as here
shown, and, again, the coils may be smaller, and more in number, or shorter
or longer as may be desired; but what I claim, and wish to protect by these
my in part recited Letters Patent is, the way of generating steam herein
generally described and exhibited.
In witness whereof, I, the said Thomas Hughes, have hereunto set my
hand and seal, this Twenty-first day of January, in the year of our
Lord One thousand eight hundred and sixty-two.
Witness,
ALFRED PERRY,
Clerk to J. S. Cockings,
Patent Agent, Birmingham.
THOMAS HUGHES.
(8.)