IMPROVEMENTS IN TUBULAR STEAM BOILERS
Year: 1871

page_text: LETTERS PATENT to James Howard, of Bedford, in the County of
Bedford, Agricultural Engineer, and Edward Tenney Bousfield, of
the same Place, Engineer, for the Invention of "IMPROVEMENTS IN
TUBULAR STEAM BOILERS."
Scaled the 1st August 1871, and dated the 1st May 1871.
PROVISIONAL SPECIFICATION left by the said James Howard and
Edward Tenney Bousfield at the Office of the Commissioners of
Patents, with their Petition, on the 1st May 1871.
We, JAMES HOWARD, of Bedford, in the County of Bedford, Agricul-
tural Engineer, and EDWARD TENNEY BOUSFIELD, of the same Place,
Engineer, do hereby declare the nature of the said Invention for
“IMPROVEMENTS IN TUBULAR STEAM BOILERS," to be as follows :—
This Invention relates to improvements on that class of tubular boilers
for which we obtained Letters Patent dated 30th December 1869,
No. 3770. In the Specification of this Patent we described our boilers
as composed of detachable sections, each of which consisted of a set of
horizontal tubes attached to one main vertical tube, the several vertical
tubes being connected at their upper ends to a transverse steam pipe.

page_text: To facilitate the circulation of the water in this boiler we sometimes
incline the sections forward in their vertical plane, thus throwing the
horizontal tubes slightly out of the horizontal, but for the convenience
of description in speaking of these tubes we shall designate them
horizontal tubes.
The design of the present Invention is to improve the construction
and increase the efficiency of this class of tubular boilers.
The first part of our Invention relates to a method of detaching the
horizontal tubes from the main tube of each group or section. Instead
of making the connections by means of the conical threaded rings or 1
with two screw bolts, the nuts of which were sunk into the face of the
main tube or by other means heretofore employed, the ends of the hori-
zontal tubes are accurately face-jointed to the main tubes, and secured
thereto either by two or more bolts with clips which embrace the main
tube, or by one bolt passing through the main tube, the object being
in either case to obtain a fastening that will admit of the parts being
disconnected on access being had to the rear of the main tube.
The second part of our Invention relates to an improved means for
promoting the circulation of the water in the tubes. This end we
accomplish by placing transversely in the main tubes directly above the
mouths of the horizontal tubes a series of plates, arched or otherwise, for
the purpose of directing the currents flowing from the horizontal tubes
towards the back of the main tube. These plates are so formed as to
present openings at each side and at the back thereof to allow for the
circulation of the ascending and descending currents. As the ascending
currents of water and steam are conducted to the back of the main tube
they will not interfere with the descending currents at the sides of the
tube, and an active circulation will thereby be maintained.
A third improvement relates to a method of supporting the internal
tubes or troughs in the horizontal tubes without forming projections on
the tubes themselves or other appliances which will interfere with the
ready withdrawal of the inner tubes for cleaning. This object we effect
by causing the extremities of cach internal tube to fit into or rest upon
suitable collars or other appliances at the ends of the outer or horizontal
tubes.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Howard and Edward Tenney Bousfield in
the Great Seal Patent Office on the 1st November 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, James
HOWARD, of Bedford, in the County of Bedford, Agricultural Engineer,
and EDWARD TENNEY BOUSFIELD, of the same Place, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of May, in the year of
our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said James Howard and Edward Tenney
Bousfield, Her special licence that we, the said James Howard and
Edward Tenney Bousfield, our executors, administrators, and assigns,
or such others as we, the said James Howard and Edward Tenney
Bousfield, our executors, administrators, and assigns, should at any time.
agree with, and no others, from time to time and at all times there-
after 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 Inven-
tion for "IMPROVEMENTS IN TUBULAR STEAM BOILERS," upon the condition
(amongst others) that we, the said James Howard and Edward Tenney
Bousfield, our executors or administrators, by an instrument in writing
under our, or their, or one of their hands 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 James Howard, on behalf of
myself and of the said Edward Tenney Bousfield, do hereby declare the
nature of our 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 Drawings hereunto
annexed and to the letters and figures marked thereon (that is to say):—
This Invention relates to improvements on that class of tubular boilers
for which we obtained Letters Patent dated December Thirtieth, One
thousand eight hundred and sixty-nine, No. 3770. In the Specification

page_text: of this Patent we described our boilers as composed of detachable
sections, each of which consisted of a set of horizontal tubes attached to
one main vertical tube, the several vertical tubes being connected at
their upper ends to a transverse steam pipe. To facilitate the circula-
tion of the water in this boiler we sometimes incline the sections forward
in their vertical plane, thus throwing the horizontal tubes slightly out
of the horizontal, but for the convenience of description in speaking
of these tubes we shall designate them horizontal tubes. The design of
the present Invention is to improve the construction and increase the
'efficiency of this class of tubular boilers.
The first part of our Invention relates to a method of connecting the
horizontal tubes of cach group or section with the main tube of the
section whereby we provide for the facile detachment of the parts (for
the purpose of repairing and cleaning the boiler) access being had to the
rear of the main tubes.
The Invention relates, secondly, to an improved means of promoting
the circulation of the water in the tubes, and, thirdly, to a method of
supporting the internal circulating tubes or troughs.
In the accompanying Drawings Sheet I. represents our Invention as
applied to marine and stationary boilers, and Sheet II. shews on an
enlarged scale and in detail our several improvements.
Fig. 1 is a vertical cross section, and Fig. 2 a front elevation of a
marine boiler constructed according to our Invention. The front plates
of one half only of the furnace being represented in place at Fig. 2;
Fig. 3 is a vertical section of a stationary boiler and its furnace shewing
some modifications in the details as compared with Fig. 1, and Fig. 4
is a vertical section taken at right angles to Fig. 3 and in the line 1, 2,
of that Figure.
In Sheet II. Figures 5 and 6 represent on an enlarged scale the
'mode of connecting the horizontal tubes with the vertical tube, and also
the lowest horizontal tube of the group with the water supply tube.
In this arrangement the horizontal tubes A have a slight taper at their
ends, and their rear ends are faced up to fit slightly conical holes made
to receive them in the front of the vertical tube B. A flanged cap C,
Fig. 5 is fitted to the front ends of the tubes A for the purpose of
closing the same. At Fig. 6 the front end of the tube A is represented
as fitting into the horizontal water supply pipe D which connects as
usual with all the sections and is fitted with caps D' directly opposite

page_text: the ends of the tubes A to permit of access to the interior of those
tubes; E, E, are screwed tie rods which are passed through the tubes A,
the vertical tube B, and the caps C or D', as the case may bc, and
receive tapped nuts at their extremitics to bind the several parts
together.
Fig. 7 shews in sectional plan another mode of connecting the hori-
zontal with the vertical tubes. In this example the rear end of the
tube A is screwed into a flanged nozzle A¹ of cast iron which forms
virtually a continuation of that tube. The nozzle is turned or faced up
to fit a slightly coned hole made in the vertical tube B. The tubes are
secured together by means of screw bolts E, E, the heads of which fit
in recesses formed in the flange of the nozzle A' while their screwed
ends pass through clips E' that embrace the vertical tube and are made
fast by nuts applied to the ends of the screw bolts.
Fig. 8 shews in vertical section a vertical tube with the horizontal
tubes connected thereto by means of short tie rods which pass through
the vertical tube instead of along its sides, as in the last described
arrangement; A¹ are the nozzles or castings into which the tubes A are
screwed, but instead of these nozzles fitting into tapered holes made in
the tube B, they are coned on their inner face to receive a collar or short
tube B' which is screwed into the tube B. These collars or short tubes
are faced up to fit the nozzles, and by means of the screw bolts E the
parts A and B are retained in close contact. The vertical tube B is
provided with transverse tubular passages through which the screw
bolts E are passed to receive the tightening nuts at their rear end.
A further modification of this part of our Invention is shewn in the
section Fig. 9 wherein a short tie bolt is used for connecting the hori-
zontal and vertical tubes together. In this example the tube B is fitted
with a short tube B', as in Fig. 8, but both its ends are slightly tapered
to fit conical holes made, the one in the side of the tube B, and the
other in the end of the horizontal tube A, which latter is partially closed
in order to form a shoulder at the end of the tube. This shoulder is
intended to receive the pressure of radial projections or spurs formed on
a hollow cylinder E', through the hub of which the tie bolt E is passed.
This cylinder is shewn detached and in edge view at Fig. 9*. On the
nut being applied to the end of this tie bolt it will by the aid of the
spurs on the cylinder E' draw the horizontal and vertical tubes into
tight contact with the short connecting tube B'. In all the above

page_text: the boiler.
The second head of our Invention which relates to an improved
means for promoting the circulation of the water in the tubes is shewn
at Figures 8 and 8*, which latter is a section of a vertical tube taken
in the line 1, 2, of Fig. 8. By reference to these Figures it will be seen
that we place transversely in the vertical or main tubes B directly above
the months of the horizontal tubes A a series of arched plates F. These
plates F are introduced for the purpose of directing the current flowing
from the horizontal tubes towards the back of the main tube, and they
are so formed and fitted as to present openings at their sides and back,
and thereby allow for the circulation of the ascending and descending
currents. As the ascending currents of water and steam are conducted
to the back of the main tube they will not interfere with the descending
currents at the sides of the tube and an active circulation will thereby
be maintained.
A third improvement which relates to a method of supporting the
internal tubes or troughs in the horizontal tubes has for its object to
remove the necessity for forming projections on the tubes themselves
or other appliances which will interfere with the ready withdrawal of
the inner tubes for cleaning. This object wc effect by causing the
extremities of cach internal tube to fit into or rest upon suitable collars
or other appliances situate at or near the ends of the outer or horizontal
tubes.
At Figures 5 and 6 the internal tubes are shewn at G, one end resting
on the end of the tube A, while the other is slidden over a ring G¹ carried
by the tie rod. A similar arrangement for supporting an open tube or
trough is illustrated at Figs. 10. In this case the tie rod extends through
a vertical bar G which serves to connect together the horizontal tubes
of the section or group and support the upper ones in position, as
illustrated in Sheet I. of the Drawings. This tie bolt also serves to
hold in place a cap or cover which closes the forward end of the tube A,
as shown also at Fig. 10*.
Another mode of supporting the internal tube is shewn at Fig. 9
where the hollow cylinder forms the bearing for the rear end of the
tube. A free passage for the water being preserved through the cylinder.
In this example the inner tube G has a continuation at G¹ projecting

page_text: into the vertical tube B, and this continuation is held in place by fitting
on to the cylinder E'.
A further modification of the manner of supporting the internal tube
or trough is shewn at Figs. 11. This is to be employed when a central
tie bolt or rod is not available for carrying the internal tube. Screwed
into the end of the tube A is a collar of cast iron A* which is mado
conical on its inner periphery. In this collar the end of the tube G is
inserted. The tube A is closed by a cap piece which is held in place
by short screw bolts and nuts (see also Fig. 11*) and as the end of the
tube G is virtually closed lateral openings are made therein as shown
to allow of the free circulation of water through the same. Other modes
of closing the ends of the horizontal tubes may be adopted as shewn at
Figures 12 and 13.
Having now set forth the nature of our Invention of "Improve-
ments in Tubular Steam Boilers," and explained the manner of carrying
the same into effect, we wish it to be understood that under the above
in part recited Letters Patent we claim,—
First. Connecting the horizontal tubes of cach group or section with
the main tube of the section in the manner and for the purpose above
described.
Secondly. The arrangement described with reference to Figures 8
and 8* of the Drawings for promoting the circulation of the water in
the tubes.
Thirdly. The means described for supporting the internal circulating
tubes or troughs.
In witness whereof, I, the said James Howard have hereunto set
my hand and seal, the Thirty-first day of October, in the year
of our Lord One thousand eight hundred and seventy-one.
TAMES HOWARD
/rol