IMPROVEMENTS IN TUBULAR STEAM GENE- RATORS
Year: 1872

page_text: LETTERS PATENT to Alexander Prince, of the Office for Patents, 4,
Trafalgar Square, Charing Cross, in the County of Middlesex,
for the Invention of "IMPROVEMENTS IN TUBULAR STEAM GENE-
RATORS." A communication from abroad by James Milnor Hicks,
of the City, County, and State of New York, United States of
America.
Scaled the 2nd May 1873, and dated the 4th November 1872.
PROVISIONAL SPECIFICATION left by the said Alexander Prince at
the Office of the Commissioners of Patents, with his Petition, on
the 4th November 1872.
I, ALEXANDER PRINCE, of the Office for Patents, 4, Trafalgar Square,
Charing Cross, in the County of Middlesex, do hereby declare the.
nature of the said Invention for "IMPROVEMENTS IN TUBULAR STEAM
GENERATORS," a communication to me from abroad by James Milnor
Hicks, of the City, County, and State of New York, United States of
America, to be as follows:-
:-
This Invention consists in the application to steam boiler tubes of a
deflector, whereby the current of heated gas is deflected from the mouths

page_text: of the tubes and caused to strike against the tube sheet. This deflector
may be made of a round or somewhat oval disc of moderate thickness,
provided with a tongue or tongues standing at about right angles
thereto; such tongues being inserted in the tube, and when in position
holding the disc opposite the opening of the tube nearly parallel. to the
tube sheet, and about at right angles to the axial line of the tube. The
distance between the outside edges of the tongues is equal or nearly so
to the inside diameter of the tube, the object of the tongue or tongues
being to hold the deflecting piece in position and to conduct, into the
tube the heat which might otherwise overheat the deflecting piece.
By increasing the width of the tongue between the end of the tube
and the disc a shoulder is formed, which serves also to keep the deflector
in place at the end of the tube. The length of this shoulder and the
consequent size of the opening between the end of the tube and the disc
can be varied to suit the case, care being taken to have this deflecting
piece at a sufficient distance from the end of the tube to allow free
passage to the currents, and so as not to obstruct the draft.
The Invention also serves as a deflector to the currents of heated
gases seeking an outlet and causes them to operate as follows:-In
ordinary boilers not provided with my deflectors the currents of heated
gases pass directly into the openings formed by the tubes tending
strongly to the centres of the openings, for the reason that in these
centres there is the least resistance offered by friction to the passage
of these currents. This tendency of the currents to flow not only
directly into the openings, but also into the centres thereof, leaves pro-
portionately unaffected by the direct currents, both the spaces of the
tube sheet between the openings made by the tubes, and also the
circumference of the tubes themselves. These interspaces of the tube
sheet constitute the most available steam making surfaces and the
deflector brings them into increased and positive action. The currents
of heated gases cannot rush into the openings made by the tubes, but
are forced to pass directly against the spaces of the tube sheet between
the openings formed by the tubes. They then having impinged against
the tube sheet between the tubes pass into the tubes. This deflecting
piece can be constructed of any suitable material and of any shape and
convenient size. It need not necessarily be made with a tongue to fit
into the tube or flue; it can be constructed so as to be held in place over
the mouth of the tube by any suitable fastening either to the tube itself,

page_text: or to the tube sheet or fire sheet, nor need these deflectors be of
necessity made separately? as two or more can be constructed together.
Another form of deflector consists of a grooved iron ball through
which the front projecting end of the tongue has passed, and to which it
is fixed, the projection being at a slight angle of deflection from the
line of the tongue passing into the tube.
The tongue may consist of a short length of square bar iron having a
pin or stem near each end to support it in the tube, or other form of
tongue may be used.
The grooved ball being covered with fire-clay or refractory material
which will resist the action of heat, the ball on one side nearest the
tube sheet terminates in tapering grooves, so that it forms a bottle
shaped piece. These deflecting pieces however constructed, fastened or
held together, can be used with advantage at both ends of the tubes or
flues, the deflecting pieces at the ends nearest the chimney causing the
currrents of heated gases in their passage through the tubes to more
closely follow the circumference of the tube, effecting greater heat and
saving fuel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Prince in the Great Seal Patent Office
on the 3rd May 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
PRINCE, of the Office for Patents, 4, Trafalgar Square, Charing Cross,
in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of November, in the year
of our Lord One thousand eight hundred and seventy-two, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto the said Alexander Prince, Her special license
that I, the said Alexander Prince, my executors, administrators, and
assigns, or such others as I, the said Alexander Prince, my executors,
administrators, and assigns, should at any time agree with, and nọ
others, from time to time and at all times thereafter during the term

page_text: 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 "IMPROVEMENTS IN
TUBULAR STEAM GENERATORS," (a communication to me from abroad by
James Milnor Hicks, of the City, County, and State of New York,
United States of America) upon the condition (amongst others) that I,
the said Alexander Prince, executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Inven-
tion, 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 Alexander Prince, 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 thereof, and accompanying Drawings, that is
to say:-
The Invention is designed for the purpose of economizing fuel in the
generation of steam in multitubular boilers, by the novel application
thereto of an arrangement of plates or tubes placed in the fire-box of
the furnaces of such boilers in a manner that they will deflect the
current of heated gas from the mouths or entrances to the tubes, and
cause it to strike or impinge against the tube sheet.
The improvements consist in so constructing and arranging the
deflection device before the open mouths or entrances to the draft tubes,
in the supporting tube sheet of a steam generator, that they may deflect
or turn the heated gases towards and against the spaces of the tube
sheet between the tube ends.
According to one arrangement of deflector I construct it of fire-clay
or metal in the form of a disc of moderate thickness provided with
projecting pieces that fit into the interior of the tube to which such
deflector is attached. When the projections are inserted in the ends of
the tube they will support the disc of which they form a part, opposite
the opening into the tube from the fire-box at a little distance there-
from, and in a position at right angles to the axial line of the tubes.
The currents of heated gas from the furnace cannot by reason of the
deflectors rush direct into the openings made by the tubes, but are forced

page_text: against the intervening spaces of the tube sheet against which they
impinge before entering the draft tubes themselves. These deflecting
pieces can be constructed of any suitable material and of any shape and
size convenient for the tubes they are designed to fit.
According to a second part of my Invention I employ in lieu of the
deflecting pieces before mentioned vertical tubes placed inside the fire-
box, directly in front of the draft tubes of the boiler, which will allow
the water from the inside of the generator to enter within the inner
walls of the said deflecting device or pipes, so as to prevent their
overheating by the action of the furnace. These deflecting pipes are
arranged so that they will enter the generator at convenient points in
the fire-box, and in such a way that they will present their surfaces
right in front of the mouths of the draft tubes at a sufficient distance
therefrom, so as not to obstruct the draught. The deflector pipes so
arranged allow a circulation of water through them which successfully
preserves them from destruction and materially adds to the efficiency of
the boiler.
In order that the Invention may be clearly understood, and to explain
it in detail, I have hereunto annexed a Sheet of Drawings on which
letters of reference are marked on corresponding parts of all the Figures
and boiler of a locomotive engine, having applied thereto the improved
disc deflectors; Fig. 2 represents the side elevation of the fire-box and
boiler of a locomotive engine, shewn part in section, in order that the
position and arrangement of the deflecting water tubes inside the fire-
box may be more readily seen; Fig. 3 represents a front sectional
elevation of the same, and shews the vertical deflecting tubes in the
interior of the fire-box; and Fig. 4 represents a horizontal section of
the same on line y, y, of Fig. 3.
In these Figures A is the fire-box, B the boiler, and C the draft
tubes, all being old and well known. parts of a multitubular boiler; a, a,
are the deflectors inside the fire-box A, which in Fig. 1 are composed of
fire-clay or metal, and are supported in their position by the projecting
tongues a, which are inserted in the ends of the draft tube to which each

page_text: one belongs. In Figs. 2, 3, and 4, an arrangement of verticalwater tubes
is shown in lieu of the discs in Fig. 1. In these Figs. b is the rear of
the fire-box which forms the tube sheet supporting the draft tubes C.
In the crown of the fire-box the ends of the vertical deflecting
tubes a, a, are secured so as to form a communication with the water
space of the boiler; their opposite ends terminate at a point in the tube
sheet b, below the draft tubes, and are also secured thereto, so that they
form a communication with the boiler; these vertical hollow pieces or
tubes a, a, are placed directly before the open mouths of the said draft
tubes C, and nearly parallel to the tube sheet b, in such a position that
the gases of combustion from the furnace in seeking an outlet into the
chimney may be turned aside, so as to first come into contact with and
impinge against the tube sheet b and vertical deflector tubes a, a, before
passing into them. The water from the boiler having free access to the
tubes a, a, through which it circulates, is a means of preserving them
from the destructive influence the heat of the furnace would otherwise
have upon them. By the employment of these deflectors the heat of
the furnace is brought into direct contact with the surfaces that distribute
it to the surrounding water.
In extreme heat the disc deflectors, shown in Fig. 1, become sooner or
later destroyed, and in order to remedy this difficulty I have applied
the tubular or hollow deflector shewn in Figs. 2, 3, and 4, which in
principle is essentially the same as the deflector described in Fig. 1, but
being hollow and directly communicating with the water of the boiler,
the circulation of the same preserves them from destruction, and at
the same time they make a valuable addition to the efficiency of the
boiler.
There are of course various ways of attaching my improvements
without departing from its principle of action. In the case of the
hollow or tubular deflectors they may be connected at one end with a
feeding mechanism for supplying the boiler with water. They may also
be connected together and be attached so as to have only one entrance
above and one below into the boiler or generator.
Having now described the nature of the said Invention, together with
the method of carrying the same into practical effect, I wish it to be
clearly understood in conclusion that I claim, the combination of the
tube sheet of a steam generator, and the disc or tubular deflectors

page_text: described, placed in front of the fire-flues or draft tubes for the purpose
of deflecting the gases of combustion against the tube sheet, and giving
circulation to the water of the boiler, as herein-before substantially
described, and set forth, and fully illustrated in the Drawing annexed.
In witness whereof, I, the said Alexander Prince, have hereunto
set my hand and seal, this Third day of May, in the year of our
Lord One thousand eight hundred and seventy-three.
ALEXR. PRINCE. (L.S.)