through the Tubes or Flues of Steam Boilers.
Year: 1887

page_text: through the Tubes or Flues of Steam Boilers.
1, MARIE AUGUSTIN DESPEISSIS, of Barkly Street, St. Kilda, in the Colony of
Victoria, Sugar Manufacturer, do hereby declare the nature of this invention to be
as follows:-
This invention of an improved means for creating an even and regular draught
through the tubes or flues of steam boilers is designed to cause the heat from the
furnace or fire-box to spread evenly and pass at a uniform rate through each and
every one of the tubes or flues, thus economizing heat and increasing the steaming
power of the boilers. This I accomplish by compelling the heated air or gases and
Hame from each and every one of the flues or tubes of the boiler to travel the same
distance to the point of exit leading to the flues at the outside top or bottom of the
boiler or those leading to the stack or chimney. For instance in fitting my invention
to a multitubular boiler in which the heat from the tubes has to pass into a back
chamber and thence to side flues leading to chimney I arrange in such back chamber
a series of baffle plates which divide off each vertical line of boiler tubes from one
another, the outer baffle plates being the widest and extending to within about
seven inches of the back of the chamber for a steam boiler having two outside flues
while for a one outside flue boiler the distance will be about fourteen inches. These
baffle plates determine the width of and angle of the remaining plates as they will
require to be of such a width and placed at such an angle as that their width added
to the distance from their back edge to the back edge of the outer baffle plate is equal
in length to the width of such outer baffle plates. These baffle plates may either be
fixed to the back end of the boiler or hinged to it so as to enable the draught to be
regulated or they may be constructed of brick-work, they are made to fit quite close
to the back end of boiler and to the top and bottom of back chamber and such plates
may be of any shape or form convenient for dividing off the boiler tubes to cause the
distance from each to point of exit to flue to be equal. When the baffle plates are
movable they are furnished with rods which pass to outside of brick work to enable
them to be adjusted or to open them to enable the boiler tubes or flues to be cleaned.

page_text: A spy hole is also provided at back of chamber to enable the currents of heated gases
and flame leaving the boiler tubes to be observed. When a boiler is constructed with
two flues or tubes the exit end of the baffle plates are arranged to be immediately
opposite the centres of the flues or tubes, but if it has only one outside flue going to
the chimney the exit end of the baffle plate is arranged to be opposite the centre of
the boiler. An alternative method in multitubular boilers is to dispense with the
baffle plates and extend the tubes backwards the requisite distance to cause an equal
travel of the gases etc. to the flues.

page_text: An Improved Means for Creating an Even and Regular Draught
through the Tubes or Flues of Steam Boilers.
I MARIE AUGUSTIN DESPEISSIS of Barkly Street St. Kilda in the Colony of
Victoria Sugar Manufacturer do hereby declare the nature of this invention and in
what manner the saine is to be performed to be particularly described and ascertained
in and by the following statement :-
This invention of improved means for creating an even and regular draught through
the tubes or flues of steam boilers is designed to cause the heat from the furnace or
fire box to spread evenly and pass at a uniform rate through cach and every one of
the boiler tubes thus economizing heat and increasing the steaming power of the
boilers. To accomplish this I provide means for compelling the heated air or gases
and flame which escape simultaneously from the several tubes to enter the flue at as
nearly as possible the same moment. If such heated air or gases and flame were at
the same temperature in every tube the object would be accomplished by making the
distance to be traversed by them from the point of exit from the several tubes to the
point of entrance to the flue exactly the same but in as much as the heated air or
gases and flame escaping from the lower tubes are always of a lower temperature
than those from the upper tubes it becomes necessary to lessen the distance which
they have to travel before reaching the entrance to the chimney. The difference in
these distances however is rarely more than an inch or two between the two extremes
that is between the highest and the lowest tube. In the case of multitubular boilers I
provide a series of battle plates for determining the distances between the exit of the
tubes and the entrance to the fluc. There may be one of these baffle plates between
the end of every line of tube and that of its neighbour or between every second line
and its neighbour or in such other positions as may be found most convenient although
if practicable and not inconvenient 1 prefer to place one between every tube and its
neighbour. As an alternative to the baffle plates on multitubular boilers I extend the
tubes to such an extent as to leave a nearly equal distance between the tube plate end
of each tube and the entrance to the flue. There may be more than one flue to each
boiler if so desired in which case they should be of equal length and sectional area.
If they are not thus-the shorter one must have a damper of some kind so as to
equalise the draught in each. Of course these flues must lead to a chimney. When
my invention is used in locomotive boilers I so arrange it as to make it useful as a
spark arrester.
These flues may be either at one or both sides at the top or at the bottom of the
boiler or they may lead directly to the stack or chimney. As an alternative they
may be brought to within a few inches of the end of the boiler by using a series of
pipes the length of which will be nearly alike and the combined area of which will
be sufficient to carry off the fumes from the boiler tubes.
In fitting my invention to a multitubular boiler A as shewn in Figure 1 in the

page_text: accompanying drawings the heat from the tubes B has to pass into a back chamber (
and from thence to side flues C¹ leading to the chimney. In such back chamber I
arrange a series of baffle plates D which divide off each vertical line of boiler tubes B
from the others the outer baffle plates & being the widest Care must be taken to allow
sufficient flue area between its back edge and the back of the chamber. These outer
baffle plates & determine the width of the remaining plates d' d as their width plus
the distance from their edgo to the edge of the outer battle plate d is about equal to
the width of such outer baffle plate. These baffle plates may either be fixed to the
back end of the boiler or be hinged to it in such a manner as to enable the draught
to be regulated. Where practicable they may be secured to the smoke box door and
in some cases they may be built up of brickwork. They are made to fit quite close
to the back end of boiler and have closed upper and lower walls. They may be of
any shape or form convenient for dividing off the boiler tubes to cause the distance
from cach to the point of exit to the flue to be approximately equal. When the
baffle plates are movable they are furnished with rods E which pass to the outside of
the brickwork or walls of the boiler so as to enable the angle of the plates to be
adjusted or to open the plates to allow the boiler tubes to be cleaned. A spy hole F
is also provided at the back of the chamber or through the smoke box door to enable
the currents of heated gases and flame leaving the boiler tubes to be observed.
When a boiler is constructed with two large tubes B as shewn in Figure 2 the exit
end of each baffle plate D is arranged to be immediately opposite the centre
of its tube.
When a boiler is of the Cornish type as shewn in Figure 3 with one large tube B
and the flue C¹ leading from one side of the back chamber C then the baffle plate or
wall D extends to immediately opposite the centre of the tube B. This figure shows
the baffle built up of brickwork.
In Figure 4 the baffle plates D are shewn arranged in the smoke box of a
locomotive boiler so as to equalise the distance which the products of combustion
have to travel from the tubes to the funnel 03. In these boilers as the tubes are
arranged very close together it will sometimes be necessary to corrugate the plates
so as to effectually divide off the tubes and in most cases it will be sufficient for all
practicable purposes to lead two rows of tubes to each space between the baffle plates
and in determining the length of the plates to take the mean between such two rows.
In Figure 5 an alternative method is shewn for arranging the baffle plates D in
the smoke box of a locomotive boiler they being in this case attached to a hood or
framing G which is secured to the end of the boiler and large enough to embrace the
whole of the tubes. The top and sides of this framing are closed while the bottom
is open and its front between the baffle plates is pierced with a sufficient number of
holes or openings G₁ to allow sufficient area for the boiler tubes. It is in the space
between the hood G and the end of boiler that the sparks are arrested. Sometimes
I cover the space at the front end of the baffle plates with a suitable grating. The
baffle plates may be hinged to the hood Ġ and the hood may be hinged to the end of
the boiler or it may be secured in any other practicable manner which will admit of
the tubes being easily got at for the purpose of cleaning them. If preferred instead
of having the grating at the front of the baffle plates such grating (or its equivalent
gauze) may be arranged over the openings Gleading to the baffle plates thus the
sparks are arrested by it and fall through the open bottom of the hood G into the
smoke box.
In Figure 6 the baffle plates D are arranged in the smoke box C of a boiler with
the exit flue C leading along its top the baffle plates being shewn supported by a
frame D¹ from the smoke box door C so that when the door is opened the baffle
plates are carried with it away from the face of the tubes thus allowing them to be
easily cleaned.
In Figure 7 shew the method of bringing the flucs to within a few inches of the
exit end of the boiler tubes B thus I arrange a series of pipes H the length of which
will be nearly alike and the mouths of which are immediately in front of the tube
openings of the boiler their other ends being led direct to the flues the combined area

page_text: of these connecting pipes being equal to the requisite flue area. This may also be
carried into effect in locomotives by arranging a chamber under the funnel and
leading a pipe from the hood or framing G before mentioned to it the blast pipe being
led as ordinarily to such chamber.
In a boiler such as shewn in Figure 1 if there should be a greater draught in one
of the side flues than in the similar flue at the opposite side of the boiler consequent
upon such first mentioned flue being nearer the point of exit leading to the chimney-
then in such cases I arrange a hinged damper which is capable of adjustment to
increase the distance of travel on such shorter flue. This damper may also be so
arranged as to act as a regulator in shunting a portion of the draught of the shorter
flue into the longer one and so equalising the draught. I also find it desirable in
such boilers to place a partition between the two sets of baffle plates-and so convert
the smoke box into two separate chambers.
Figure 8 shews how the baffle plates may be dispensed with on multitubular boilers
the tubes being extended to such a degree as to leave a nearly equal distance from
the tube plate end of each to the point of entrance to the flue.
Having now particularly described and ascertained the nature of my said inven
tion and in what manner the same is to be performed I declare that what
I claim is:
1. In steam boilers having only one tube such as Cornish boilers-the addition of
a baffle plate so arranged as to make the heated air or gases and flame simultaneously
issuing from the several parts of the tube to simultaneously enter a flue leading to
the chimney substantially as herein described and as illustrated in Figure 3 of my
drawings.
2. In steam boilers having two or more tubes the addition of baffle plates at the
exit end of such tubes so arranged as to compel the heated air or gases and flame
simultaneously issuing from the several tubes to simultaneously reach the entrance
to the flue or flues leading to the chimney substantially as herein described and as
illustrated in Figures 1, 2, 4, 5, 6 and 7 of my drawings.
3. In multitubular steam boilers the extension of the tubes to such a degree as to
leave a nearly equal distance from the tube plate end of each to the point of entrance
to the fluc substantially as herein described and as illustrated in Figure 8 of
my drawings.
4. The use of one or more pipes for bringing the flues to within a few inches of the
front of the boiler tubes substantially as and for the purposes described and as
illustrated in Figure 7 of my drawings.
Dated this Sixteenth day of August One thousand eight hundred and eighty seven.