IMPROVEMENTS IN THE CONSTRUCTION OF STEAM BOILERS
Year: 1868

page_text: LETTERS PATENT to James Howard, Agricultural Engineer, and
Edward Tenney Bousfield, Engineer, both of Bedford, in the County
of Bedford, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION
OF STEAM BOILERS."
Sealed the 21st April 1868, and dated the 8th February 1868.
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 8th February 1868.
We, JAMES HOWARD, Agricultural Engineer, and EDWARD TENNEY
BOUSFIELD, Engineer, both of Bedford, in the County of Bedford, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE CONSTRUCTION OF STEAM BOILERS," to be as follows:-
This Invention relates to certain improvements in the construction
of that class of boilers for which we have already obtained Letters
Patent bearing date respectively January 23rd 1866 (No. 226),
July 10th 1866 (No. 1811), and January 11th 1867 (No. 76), the
object being to improve the construction and increase the efficiency of
such boilers. This class of boilers may be said to consist of arrange-

page_text: ments of vertical tubes connected together at top and bottom by
horizontal tubes to form groups or sections, which sections are brought
into communication at top and bottom by pipes running at right angles
to the horizontal tubes just named, and forming respectively feed water
and steam pipes. Hitherto in manufacturing our improved boilers we
have placed the several sections of tubes transversely of the furnace and
heating chamber, and we have connected the bottom horizontal tube
of each section with a feed water pipe common to all. These connections
were made underneath the bottom horizontal tubes (the ends of which
were closed).
According to our present Invention, in order to afford increased
facility for removing calcareous or other deposits from the bottom of the
sections, and also to adapt the boiler to confined positions, as, for
example, where the front only of the furnace can be approached, we
propose to place the sections longitudinally of the furnace and heating
chamber, and to gain access to the lower horizontal tubes of the sections
through their front ends. Across the front ends of the lower
longitudinal tubes of all the sections a feed water pipe passes having
openings on one side corresponding with the openings in the ends of the
lower horizontal tubes of the sections and sockets to receive the ends
of those tubes. On the opposite side of the fced water pipe and
coinciding with the openings are other and like openings which are
closed by lids or bonnets. This arrangement admits (by simply
removing the bonnets) of the introduction of a scraper to remove any
deposit that may form on the bottom tubes. In order to support the
sections their front ends may rest on a plate over the firc-door, and those
furthest from the fire may be carried by a perforated wall of fire-brick,
which will allow of the current of heated gases passing out of the fire
chamber with the view of being returned to act on the upper part of
the boiler. The further end of the sections may also be suspended from
a bar secured to the upper side of the bottom tubes or by a bar passing
through the same, in which cases the perforated wall would not be
required. In cases where it is desirable to increase the water space in
the lower horizontal tubes we propose to make them of sufficient
diameter to receive two or more rows of vertical tubes instead of one
row as heretofore. In order to increase the surface of the water at the
water line, and thus to diminish the variation in the height of the water
level, we propose to swell out the vertical tube at that point in a
spherical form. In a line with the horizontal axis of these spheres we

page_text: divide the furnace into upper and lower chambers, and the flame and
heated gases after passing out of the lower chamber we turn into the
upper to heat the upper part of the sections of the boiler.
Another part of our Invention has for its object to increase the
efficiency of the inner circulating tubes and incidentally to allow of the
cleaning out of the horizontal tubes as above explained. Heretofore we
have formed these tubes with open ends and cut vertical wedge-shaped or
pointed slits through the ends to provide for the circulation of the water.
By this arrangement, however, the upward and downward currents
somewhat interfere with each other, and as these internal tubes rest on
the bottoms of the sections they would effectually prevent the intro-
duction of the scraper, as above described. To remedy these defects we
propose to suspend the inner tubes clear of the bottom of the sections
by fitting them with wing pieces which will rest upon the shoulders of
the couplings of the longitudinal tubes. We also close or nearly so the
bottom of the pendent inner tubes, bringing them to the form of an
inverted cone, and just above the cone we make lateral openings in the
tubes so that the descending water may flow through the same. We
adopt the form of the inverted cone, as it offers the least resistance to
the upward flow of the heated water. In order to facilitate the fixing of
the flue division and top covering plates in cases where the top of the
boiler is not accessible we purpose to connect the top and division plates
together, and fit them to the section before putting the sections in
place; by this arrangement, when the sections are set side by side in
the furnace, the flues will be complete. In order to utilize as far as
may be the heat of the gases of combustion before they escape into the
chimney we set in the flue leading to the chimney a group of short
sections through which we cause the feed water to circulate on its
passage to the larger sections or boiler proper. These short sections
are fitted with internal circulating pipes. With the view of effecting
the more perfect combustion of the fuel in the furnace we propose to
use perforated fire-brick bars, which will take the place of certain of
the ordinary fire-bars, and by being raised above the level of the fire
and set at suitable distances apart will distribute a constant stream of
heated air over the surface of the burning fuel in the best form for
admixture with the gases generated by the combustion of the fuel.

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 8th August 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
HOWARD, Agricultural Engineer, and EDWARD TENNEY BOUSFIELD,
Engineer, both of Bedford, in the County of Bedford, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of February, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
first 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
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 "IMPROVEMENTS IN THE CONSTRUCTION OF STEAM BOILERS," upon the
condition (amongst others) that we, the said James Howard and
Edward Tenney Bousfield, our executors or administrators, by an instru-
ment in writing under our, or their, or one of their hands and scals,
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 Scal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that we, the said James Howard and 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 Drawing hereunto annexed, and to the letters and
figures marked thereon (that is to say) :-
This Invention relates to certain improvements in that construction
of that class of boilers for which we have already obtained Letters

page_text: Patent bearing date respectively January Twenty-third, One thousand
eight hundred and sixty-six (No. 226), July Tenth, One thousand eight
hundred and sixty-six (No. 1811), and January Eleventh, One thousand
eight hundred and sixty-seven (No. 76), the object being to improve the
construction and increase the efficiency of such boilers. This class of
boilers may be said to consist of arrangements of vertical tubes con-
nected together at top and bottom by horizontal tubes to form groups or
sections, which sections are brought into communication at top and
bottom by pipes running at right angles to the horizontal tubes just
named, and forming respectively feed water and steam pipes. Hitherto
in manufacturing our improved boilers we have placed the several
sections or groups of vertical tubes transversely of the furnace and
heating chamber, and we have connected the bottom horizontal tube of
cach section with a feed water pipe common to all. These connections
were made underneath the bottom horizontal tubes (the ends of which
were closed).
According to our present Invention, in order to afford increased
facility for removing calcarcous or other deposits from the bottom of
the sections, and also to adapt the boiler to confined positions, as, for
example, where the front only of the furnace can be approached, wo
propose to place the sections longitudinally of the furnace and heating
chamber, and to gain access to the lower horizontal tubes of the sections
through their front ends.
This improvement is illustrated in Sheet I. of the accompanying
Drawings, where Fig. 1 is a longitudinal sectional clevation of the
improved boiler; Fig. 2 is a plan or top view of the same; Fig. 3 is
a front elevation, and Fig. 4 is a transverse section taken in the line
1, 2, of Fig. 1.
A is the fire-place, above which are set the sections or groups of
vertical tubes B connected together at bottom by the longitudinal water
pipes C and at top by the longitudinal steam tubes D through the short
coupling tubes d which are screwed into tapped holes in the closed top
ends of the tubes B. The tubes D are closed at their front ends, and
their rear ends connect with a transverse pipe D', from which the steam
is taken from the boiler. Across the front ends of the lower longitudinal
tubes C of all the sections a feed water pipe E passes having openings
on one side corresponding with the openings in the ends of the lower
horizontal tubes of the sections and sockets to receive the ends of those

page_text: tubes. On the opposite side of the feed water pipe and coinciding with
the openings are other and like openings which are closed by lids or
bonnets e, e; this arrangement admits (by simply removing the
bonnets e) of the introduction to the bottom of the boiler of a scraper
for the purpose of removing any deposit that may form on the bottom
tubes. In order to support the sections their front ends may con-
veniently rest on a plate F over the fire-door, and those furthest from
the fire may be carried by a perforated wall of fire-brick G through
which the current of heated gases after playing upon the under side of
the longitudinal pipes C will pass from the fire chamber. With the
view of exhausting as much as possible the heat of the gases of
combustion the current is now turned back so as to circulate among the
tubes B. The space containing the tubes is divided by a horizontal
partition II into two flues, the longitudinal pipes C forming the floor of
the lower flue, and the plates II' forming the roof of the upper fluc.
The heated gases after circulating among the tubes in the lower fluo
and following the course of the arrows are turned into the upper flue
to act on the upper part of the boiler. The horizontal partition II is
composed of plates formed to fit around and fill the space between the
vertical tubes, as shewn in the plan view, Fig. 2; these plates are
supported by transverse ribbed girders h, the ends of which rest on a
ledge of the brickwork. The plates II' (see Fig. 1) in like manner fit
around the coupling tubes d and are supported on the top of the
tubes B. In cases where it is desirable to increase the water space in
the lower horizontal tubes we propose to make them of sufficient
diameter to receive two or more rows of vertical tubes instead of one
row as heretofore. This modification is illustrated at Fig. 5, Sheet II.,
where two rows of tubes B, B, are bedded side by side in sockets cast
for them in the longitudinal tube C. In order to increase the surface
of the water at the water line and thus diminish the amount of variation
in the height of the water at or about the mean water level consequent
on the variation of the quantity of water in the boiler we propose to
swell out the vertical tubes in a spherical form at that level, as shewn
at Figures 6 and 7, Sheet II. These spherical enlargements will in
coming together assist in forming a barrier to the escape upwards of the
heated gases; this barrier we complete by the aid of filling plates, as
described with reference to Fig. 1, in order that the heated gases may
be caused to traverse to the front of the furnace (as in Fig. 1) before
reaching the upper parts of the tubes.

page_text: Another part of our Invention has for its object to increase the
efficiency of the inner circulating tubes and incidentally to allow of
the cleaning out of the horizontal tubes, as above explained. Heretofore
we have formed these tubes with open ends and cut vertical wedge-
shaped or pointed slits through the ends to provide for the circulation
of the water. By this arrangement, however, the upward and downward
currents somewhat interfere with each other, and morcover, if these
internal tubes rested on the bottoms of the sections, as they have
hitherto done in our boilers, they would effectually prevent the intro-
duction of the scraper into the pipes C. To avoid these inconveniences
we now suspend the inner tubes 15 I (see Fig. 1), clear of the bottom
of the sections by fitting them with wing pieces i, i, which will rest
upon the sockets of the longitudinal pipes C. We also close or nearly
so the bottom of the pendent inner tubes, bringing them to the form
of an inverted cone, and just above the cone we make lateral openings
** in the tubes so that the descending water may flow through the same.
We adopt the form of the inverted cone, as it offers the least resistance
to the upward flow of the heated water.
It may be well here to remark that in order to facilitate the fixing
of the flue division H where that is used and the top covering plates II',
in cases where the top of the boiler is not accessible, we purpose to
connect the top and division plates H and H' together by coupling
rods, and to shape them as shewn at Figs. 8 and 9, Sheet II., that
they may be fitted to their several sections before the sections are put
in place; by this arrangement, when the sections are set side by side
in the furnace, the flues will be complete.
In order further to utilize the heat of the gases of combustion
before they escape into the chimney K we set in the fluc leading to
the chimney a group of transverse sections composed of short vertical
tubes L connected together only at their upper ends, and that by
flange couplings. The tubes L are each fitted with a cover to afford
access thereto for cleaning, and the sections are connected together at
their ends by means of tubes M. Through these sections we cause the
feed water to circulate in order that it may become heated before
entering the larger sections or boiler proper. After circulating through
these small sections the now heated water passes off by a pipe N, Fig. 2,
and enters the boiler, as shewn at O in the front clevation, Fig. 3,

page_text: Sheet I. The short sections are fitted with internal pendent circulating
tubes.
Having now set forth the nature of our Invention of "Improvements
in the Construction of 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. Constructing the sections of the boiler and arranging them in
the furnace and fitting the dividing and top covering plates thereto,
in the manner and for the purpose above explained with reference to
Sheet I. of the Drawings.
Seconly. The means above described for reducing the amount of
variation in the height of the water line.
Thirdly. The improvement in the means of keeping up the circulation
of the water in the tubes B.
And, lastly. The employment of the supplementary sections for heating
the supply water for our improved boilers.
In witness whereof, we, the said James Howard and Edward
Tenney Bousfield, have hereunto set our hands and scals, the
Seventh day of August, in the year of our Lord One thousand
eight hundred and sixty-eight.