AN IMPROVED CONSTRUCTION OF STEAM GENERATOR
Year: 1867

page_text: LETTERS PATENT to Alfred Vincent Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Mechanical Draughts-
man, for the Invention of "AN IMPROVED CONSTRUCTION OF STEAM
GENERATOR." A communication from abroad by Eli Thayer, of Wor-
cester, in the State of Massachusetts, Sabin Peters Pond, of Providence,
and Daniel Bullard Pond, of Woonsocket, both in the State of Rhode
Island, United States of America.
Sealed the 5th July 1867, and dated the 2nd February 1867.
PROVISIONAL SPECIFICATION left by the said Alfred Vincent Newton
at the Office of the Commissioners of Patents, with his Petition, on the
2nd February 1867..
I, ALFRED VINCENT NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Mechanical Draughtsman, do hereby
declare the nature of the said Invention for "AN IMPROVED CONSTRUCTION OF
STEAM GENERATOR," to be as follows:-
This Invention consists in so constructing and arranging the different parts
of a steam generator that while the fire surface may be very great and

page_text: exposed to the highest heat of the furnace there shall be constant and rapid
circulation of water and steam over every part of it, preventing the injurious
beating of the metal of the generator, and the formation or adhesion of
steam globules upon its inner surface; this mode of construction will also
secure cheapness, simplicity, and compactness of form with the greatest possible
safety, efficiency, and economy in use.
The steam generator may be described as a series of horizontal or it may
be inclined tubes arranged in parallel rows one above the other, and all com-
municating with a vertical chamber, into which they discharge the steam as it
is generated in the tubes. The front ends of these tubes are closed, and they
are so disposed by contracting the length of some of the rows as to form
amongst them a fire-chamber, and above that chamber with rows of tubes
intervening a charging chamber for supplying the fire with fuel, which fuel
falls upon the underlying tubes and burns there as upon grate bars. If the
fuel does not in sufficient quantity find its way to the fire-place proper, then
fresh fuel is fed directly to that part, doors extending over the whole width of
the furnace being provided both for the fire-chamber and the feeding chamber.
Within each tube is inserted a smaller tube which extends to near the closed
ends of the outer tubes and through the vertical chamber before mentioned to
a similar feed water chamber; these two chambers extend from below the
lowest line of tubes upwards above the highest line where the feed water
chamber terminates in a cylindrical vessel containing the feed water, and also
the accumulated steam generated in the tubes. The discharge steam
chamber continues up above the water line in this cylinder and thus delivers
the steam into the steam space. The downward pressure of the water causes
it to distribute through all the internal tubes, and escaping from these tubes a
back circulation is created; thus the globules of steam are swept along and
caused to discharge into the vertical discharge chamber; although therefore
many of the tubes are in contact with the incandescent fuel there is a suffi-
ciently rapid circulation of the water to ensure a rapid absorption and
utilization of the heat, and the tendency of the coal to form clinkers will also
be removed. If thought desirable a double set of tubes, may be used, and in
that case a second discharge chamber will be required in juxtaposition with
the water supply chamber.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alfred Vincent Newton in the Great Seal Patent Office ou
the 2nd August 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
VINCENT NEWTON, of the Office for Patents, 66, Chancery Lane, in the County
of Middlesex, Mechanical Draughtsman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of February, in the year of our
Lord One thousand eight hundred and sixty-seven, in the thirtieth year
of Her reign, did, for Herself, Her heirs and successors, give and grant.
unto me, the said Alfred Vincent Newton, Her special licence that I, the
said Alfred Vincent Newton, my executors, administrators, and assigns,
or such others as I, the said Alfred Vincent Newton, 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 CONSTRUCTION OF STEAM
GENERATOR," being a communication to me from abroad, upon the condition
(amongst others) that I, the said Alfred Vincent Newton, my executors.or
administrators, by an instrument in writing under my, or their, or one of their
bands and seals, 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.
NOW KNOW YE, that I, the said Alfred Vincent Newton, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the Drawing hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
This Invention consists in so .constructing and arranging the different parts
of a steam generator that while the fire surface may be very great and
exposed to the highest heat of the furnace, there shall be constant and rapid
circulation of water and steam over every part of it, preventing the injurious
beating of the metal of the generator and the formation or adhesion of steam
globules upon its inner surface; this mode of construction (as will be shown
hereafter) will also secure, cheapness, simplicity, and compactness of form.

page_text: with the greatest possible safety, efficiency, and economy in use. To enable
rothers skilled in the art to make and use the improved steam generator, I will
proceed to give a description of its construction and mode of operation..
Fig. 1 represents a longitudinal vertical section of the steam generator;
Fig. 2 represents a transverse vertical section in front of the bridge wall and
through the furnace; Fig. 3 represents the furnace front; and Fig. 4 repre-
sents a single tube of the generator on a larger scale than shown in the other
Figures, for the purpose of exhibiting more clearly its construction and con-
nection with the supply and discharge chambers of the boiler. As these tubes
are all constructed and attached in the same way and differ only in length'
and size a description of one will be a description of all.
b
In Fig. 4 a represents a pipe or tube of metal one and a half inches internal
diameter, one end of which is closed by being welded together, filled with a
plug or covered by a cap; the other end is open and securely screwed into
the side of the discharge chamber e at the point d; b represents a metallic
pipe or tube whose external diameter is less than the internal diameter of the
pipe a and lying within a; this pipe b is open at both ends, one end being
securely screwed into the supply chamber f of the boiler at the point c; the
pipe 6 may properly be called a supply pipe, and the pipe a a discharge pipe.
Suppose now that water is poured into the supply chamber.f until it rises
several inches above the point c the water. will flow through the supply pipe b
and back through the space between the outer surface of 6 and the inner
surface of a into the discharge chamber e, until it rises in the discharge
chamber to the same height as in the supply chamber. Now if the supply
chamber f and the discharge chamber e have no communication with each
other, except as above described, below the surface of the water, and if the
capacity of the discharge chamber e be not very much greater than the
capacity of the space between the pipes a and b, then when sufficient heat is
applied to the pipe a (which is horizontal or nearly so) there will be formed a
rapid circulation of water through the pipe b, and of water and steam through
the space between the two pipes into and through the discharge chamber e.
If the water in the supply chamber f stands three feet above the point ċ, and
the tubes a and b be respectively one and a half and three-fourths inch internal
diameter, and not exceeding twelve feet in length, they may be embedded in
the burning coal of a powerful furnace throughout their entire length without
injury, so rapid is the circulation of water and steam through and. between
them, and so swiftly is the heat of the metal carried away in steam. If now
instead of this single combination of a and b we suppose several hundred such,

page_text: with a corresponding increase of the size of the chambers e and f, the first
connected above with a steam chamber into which it discharges, and the other
connected with a water chamber. from which it receives its supply, we shall
have a very correct idea of the steam generator represented by Figures 1, 2,
and 3. The longitudinal section, Fig. 1, shows how the power of a steam
generator of this kind can be doubled by having a furnace and tubes a, a¹,
and b, b', on opposite sides of the supply chamber f, and leading respectively
into and through the discharge chambers 6 and 6'.
I proceed now to a more full description of the construction and mode of
operation of this steam generator, and for this purpose will use the section
represented by Fig. 1. g is a plain cylinder to be made of sufficient strength
to sustain any required pressure, and of capacity in proportion to the extent
of the fire surface of tubes connected with it by means of the chambers e, e,
and f. These chambers together form a surface of the four sides and one end
of a rectangular parallelopipedon, excepting that inside the cylinder that
portion of the two sides between the chambers e and e¹ is wanting; the width
of these chambers is most conveniently made less than the diameter of the
cylinder, so that the water may flow around the discharge chambers and el
into the supply chamber f so long as any water may remain in the cylinder.
The supply chamber only extends as high as the bottom of the cylinder, but
the discharge. chambers e and e' extend up into the cylinder above the high-
water. line u, or perhaps one-third of the length of the cylinder. These
chambers have their bases in the same horizontal plane, which is so much
below the lowest tier of the steam and water pipes that the adjacent portion.
of the chambers becomes the sediment extractor of the boiler, and should be
supplied with blow-off cocks; y represents the bridge wall built of solid
masonry from the bottom of the ash-pit r, and extends entirely across the
furnace and as high as needed, at least several inches above the top of the
feed chamber m, m; this wall should be built at the same time that the pipes
passing through it are inserted in their places, so as to make the work-per-
fectly tight and compact about then; 3, 3, represent the furnace, and m, m,
the feed chamber. Between this chamber and the furnace, each of which has
doors n opening the entire width of the furnace front, as shewn in Fig. 3,
there are several tiers of pipes, as seen in Figures 1 and 2; the number and
size of the pipes of this generator must vary according to the power required:
For a boiler of one hundred horse-power pipes are used for the outside of
extra strong iron and of one and a half inch internal diameter; the inner pipes
are of ordinary thickness, and three-fourths of an inch internal diameter: In-a

page_text: boiler of the power above named there would be about one hundred and sixty
double pipes of the kind just named, each twelve feet long, and placed in the
furnace as shewn in Fig. 2; the lower tier of these pipes (that is to say) those
between the ash-pit and the furnace s, s, are six inches apart between
¡centres, and having the welded ends resting on a bearing bar in front, serve
as the "tubular supporters of grates." The welded ends of the other long
pipes pass through a cast-iron plate securely built into the masonwork
three or four inches back, of the furnace front, Fig. 3, and are. therefore
free to move backward and forward as; the pipes. may expand or contract,
without in any degree straining the threads by which the pipes are attached to
the discharge chamber e. The welded ends of the short pipes, viz*, those
back of the furnace and feed chamber, are sustained by the bridge wall; the
number of these will of course depend upon the height of the furnace and
feed chamber, but in the present plan, as seen in Fig. 2, there would be two
tiers back of the furnace 8, s, and one tier back of the feed chamber m, m;
about thirty-six in all. As the external diameter of the outside pipes is about
two inches we should have as the fire surface in the steam: generator above
described one thousand and sixty-eight square feet; this.estimate does not
include the surface of the chambers e, f, and e¹, around which the draught
should be made to pass. The depth of the furnace from. the bottom of the
pipes over it to the grates is eight inches of the feed chamber, which has pipes
for grates five inches; no two pipes are nearer to each other than the length
of their external diameter. Suppose now that the cylinder g is filled with
water to some point between u and v, the high and low water lines, having
the upper part of the cylinder as the steam' space, the water flows through the
inner pipes b, entering at the points c, c, c, and returns between the two pipes
a and b, entering the discharge chamber eat the points d, d, d; the water
will then stand on the same level in e as in f. (In case the second discharge
chamber is constructed in a boiler for future use when it may be needed, it
should until such use have a communication with f so as to be a part of the
supply chamber). The fire being now lighted the first effect is to produce
steam in the spaces between the outer and inner pipes, which steam presses
equally towards the supply apertures c, c, c, and the discharge apertures d, d, d,
while a part escapes through both or is condensed, but very soon the force of
the steam drives the water entirely, out of the discharge chamber e, and there
is established a constant and rapid current through the pipes and between
them from c to d, the motive power of which is the difference in weight
between the column of water and the column of steam.
After the fuel in the

page_text: furnace has become thoroughly ignited coals should be shovelled into the feed
chamber, and allowed to fall among the pipes till the spaces between them are
full. The pipes make the coal easily permeated by the heat and gases from
the fire below by partly sustaining its weight and thus preventing its massing
together or "clogging." In this way the coal is burned in actual contact
with the fire surface of the boiler to any extent that may be desired.
As soon as the fire needs cleaning the furnace is opened and the ashes
sifted through the grate. The coal in this furnace will consume much sooner
than that lying among the pipes above the furnace; hence the furnace may
be nearly empty while the space above it is full of partly consumed coal;
in this case the furnace should be replenished with fresh coal. The coni-
bustible gases arising from this must traverse and permeate the already
ignited coal above, thus securing the most perfect combustion. For the
purpose of removing any cinder or other obstruction which may get among
the pipes lying between the furnace and feed chamber the doors w, w, aro
provided in the walls of the generator, as seen in Fig. 2, through which with
a common slash bar every point in the many tiers of pipes can be reached.
It may in some cases be desirable to have even a second feed chamber above.
m, m, or a feeding door even in the top of the structure above all the pipes for
the purpose of throwing down coal to be consumed in contact with the pipes,
but the plan above given is probably the best for ordinary use. Instead
also of the discharge chamber e, which all the pipes have in cominon,
there might be a separate discharge pipe for each double pipe a, b, (Fig. 1).
or one discharge pipe for several of the double pipes, but this plan would be
more complicated and expensive than the one above described of having a
common discharge chamber for all the pipes in which steam is formed. It
will be observed that the supply aperture for each double pipe a, b, is c
(Fig. 1), while the discharge aperture for each and all of the double pipes
is z, the upper end of the discharge chamber e.
We have thus far described the steam generator without dwelling particularly
upon its most important feature, namely, the several pipes or tiers of pipes
between the feed chamber m, m, and the furnace s, s. While these pipes
constitute the most effective part of the generator, in the production of steam
on account of their contact with the incandescent coal, they also subserve'
another very important purpose to which attention is now invited. When
the coal is shovelled into the feed chamber and allowed to fall among these
pipes; it does not occupy or fill all the space between them. Under each-pipe
there will be left an air space as long as the pipe and as wide as its diameter,

page_text: averaging about one inch in depth, while between the pipes in the same
horizontal tier the coal lies very lightly as its weight is mainly or entirely
sustained by the adjacent pipes. It is obvious then that this minute division
of the coal by the supporting tubes greatly facilitates the passage of air
through the fuel for the support of combustion. If, however, the coal should
be, of very great depth for the purpose of containing or covering a large
number of tubes, it might be necessary to admit air from the furnace front
directly under a part or all of the pipes so embedded in the coal.
We see
then that these pipes between the feed chamber and the furnace or (if the
furnace be also filled with them) between the feed chamber and the grate,
serve to support the coal to increase air spaces in it, thereby promoting
combustion and to generate steam. They also effectually prevent the for
mation of "clinker," for the heat of the fire is so rapidly carried away by the
passing water and steam, that the coal and ashes among the pipes cannot be
melted. With reference therefore to the mechanical effect of these pipes as
above described embedded in the coal, whether one tier or more, the Inventor
has named them the "upper grate." This grate may be used with such a steam
generator as above described, or with any other of which, as of the above, it
may form a part.
It may not be necessary, though it is pertinent to say here that this Invention
is based upon new views of radiant heat, and is a reduction of such views to
practice. In accordance with this new theory it is found that the steam
generated in these embedded pipes, constituting the upper grate, is made by
heat which would otherwise be of little or no use, and does not therefore
materially diminish the power of the fire for accomplishing other work. In
the Drawings and description above given I have represented a vertical
boiler for containing the steam and water, but a horizontal one could
perhaps in many locations be used with better economy. I have also
represented a bridge wall, but this may be dispensed with by bringing the
discharge chamber forward to the back end of the furnace. This method
would be preferable with a horizontal boiler lying above the pipes and parallel
with them..
Having .now set forth the nature of the Invention of "An Improved.
Construction of Steam Generator, as communicated to me from abroad,
and explained the manner of carrying the same into effect, I wish it to
be understood that under the above in part recited Letters Patent, I claim,-
First, the discharge chamber e in combination with a tubular steam generator,
substantially as set forth.

page_text: Second, the arrangement of the several doors n, n, w, w, for feeding the fuel
among the pipes constituting the upper grate, and for clearing them of cinder
or other obstructions, substantially as set forth.
Third, the feeding chamber m, m, substantially as set forth.
Fourth, the upper grate, substantially as set forth.
In witness whereof, I, the said Alfred Vincent Newton, have hereunto
set my hand and seal, the First day of August, in the year of our
Lord One thousand eight hundred and sixty-seven.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
A. V. NEWTON. (L.S.)