IMPROVEMENTS IN APPARATUS FOR HEATING AND EVAPORATING LIQUIDS AND FLUIDS.
Year: 1864

page_text: LETTERS PATENT to Arthur Auckland Leopold Pedro Cochrane, of
Portsmouth, in the County of Hampshire, Captain in the Royal Navy,
for the Invention of "IMPROVEMENTS IN APPARATUS FOR HEATING AND
EVAPORATING LIQUIDS AND FLUIDS.
PROVISIONAL SPECIFICATION left by the said Arthur Auckland Leopold
Pedro Cochrane at the Office of the Commissioners of Patents, with
his Petition, on the 24th August 1864.
I, ARTHUR AUCKLAND LEOPOLD PEDRO COCHRANE, of Portsmouth, in the
County of Hampshire, Captain in the Royal Navy, do hereby declare the
nature of the said Invention for" IMPROVEMENTS IN. APPARATUS FOR HEATING
AND EVAPORATING LIQUIDS AND FLUIDS," to be as follows:-
My improvements have reference to heating and evaporating vessels
generally, but more especially to boilers for evaporating water and generating
steam, and most particularly to marine engine boilers, in which economy of
space and fuel are essential features, and they consist in so constructing the
furnace or fuel chamber. of the boiler that the heated products of combustion
are caused to be retained in the upper part or crown thereof for a longer
period than they would otherwise be, and are thereby prevented from readily.
escaping by the uptake leading to the flue, a more complete combustion of
-the-gases evolved from the coal, and consequently a higher temperature
is obtained, and this I effect by placing a check or inverted bridge of suitable
[Prix Bl

page_text: material, but preferring a hollow water bridge, the inner part of which is
open to the body of water within the boiler. As such a bridge is exposed to
a most intense heat, and liable to be destroyed by the cutting action of the
inflamed gases, which by it are deflected downwards and pass on both sides of
it, producing most intense evaporation at that part, I construct within the
water space a chamber or arrangement of tubes by which a current of water
is directed from the body of the water in the boiler to the bottom of the bridge
or water space,..and thus. .supplies the deficiency which would be otherwise
caused by the upward current of the water and steam from immediate contact
with the plates forming, the upright sides of the bridge, or water space. I
further use this inverted bridge in combination with a second bridge at the
termination of the flue or tube chamber (where such is used), and which
latter I make (by preference) adjustible, so as to cause the retention of the
combusted gases in contact with the heating surface of the flue or tube
chamber in a greater or less degree, and also to admit of the adjustment of
the temperature and the. velocity of the products of combustion through the
furnace chamber and flues of the boiler. And I further employ, in combi-
nation with these. improvements, a fan in .connection with the apparatus, or
a modification thereof as patented by me, bearing date the 9th Nov. 1863,
No. 2780, for the purpose of injecting a current of atmospheric air into the
furnace, in which case the ash-pit and furnace mouth are to be closed with
an air-tight door to each, that to the furnace mouth being connected with
a valve or other known device for regulating the current of air through the
supply pipe by a rod and lever or suitable. device, so that whenever the
furnace door is opened for the purpose of supplying the furnace with fresh
fuel, the current of air shall be simultaneously stopped so as to prevent the
inconvenient discharge of air and flame from the furnace mouth. I also apply
to the upper ends of the vertical water tubes, (where such are used) cones or
suitably formed deflecting surfaces, to direct or deflect the current of steam
and water which rises vertically from the mouths of the tubes into a horizontal
direction or approximating to it, so as to diminish the priming effect of the
vertical current.
These improvements have the effect of increasing the evaporating power
of a boiler, and consequently of reducing the dimensions and weight of a
boiler for a given amount of evaporation, and thus economize the cost and
the fuel for working the same.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Arthur Auckland Leopold Pedro Cochrane in the Great
Seal Patent Office on the 24th February 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ARTHUR
AUCKLAND LEOPOLD PEDRO COCHRANE, of Portsmouth, in the County of
Hampshire, Captain in the Royal Navy, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of August, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Arthur Auckland Leopold Pedro Cochrane, Her special licence
that I, the said Arthur Auckland Leopold Pedro Cochrane, my executors,
administrators, and assigns, or such others as I, the said Arthur Auckland
Leopold Pedro Cochrane, my 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 Invention for "IMPROVE.
MENTS IN APPARATUS FOR HEATING AND EVAPORATING LIQUIDS AND FLUIDS," upon
the condition (amongst others) that I, the said Arthur Auckland Leopold Pedro
Cochrane, my executors or administrators, by an instrument in writing under
my, 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 Arthur Auckland Leopold Pedro
Cochrane, do hereby declare the nature of my said Invention, and in what
manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement and accompanying Drawing, that is
to say:-
My improvements have reference to heating and evaporating vessels
generally, but more especially to boilers for evaporating water and generating
steam, and most particularly to marine boilers in which economy of space and
fuel are desiderata, and they consist in so constructing the furnace or fuel
chamber of the boiler that the heated products of combustion are caused to
be-retained-therein for a longer period-than-they would-otherwise be with

page_text: furnaces of ordinary construction, and being thereby prevented from readily
'escaping by the uptake leading to the flue or chimney, a more complete com-
'bustion of the gases evolved from the fuel, and consequently a higher tem-
perature is obtained; the heated products so produced are applied to my
improved arrangements of evaporating surfaces, whereby I effect a saving of
fuel, rapidity of evaporation, and a consideration in the size or dimensions, and
consequently the weight of boilers of given power. And my improvements
consist as follows:-
First, in the application of a hanging or inverted bridge to the extreme end
of the furnace, either before or behind the ordinary bridge as circumstances
may require, and of such form and dimensions that the heated products of
combustion will be retained longer in contact with the crown of the furnace
and of a higher temperature than if they were allowed to escape in the
ordinary manner to the uptake. I employ when necessary a circulator within
such bridge, so that the heated surface of the métal may at all times be
adequately supplied with water and the metal be preserved from being burnt
or otherwise injured, and this may be effected in the manner shewn in the
Drawing hereunto annexed, or by an equivalent substitute.
Secondly, in the application of unequally spaced tubes, when employed for
the passage of water through them, as in water tube boilers. By this arrange-
ment the products of combustion are allowed to penetrate into the body of
"the tube chamber without encountering a sudden check like that presented
by the ordinary arrangement of uniformly spaced tubes, and becomes virtually
an extension of the combustion chamber, which by conducing to a more
complete mixture of the products of combustion causes the flame to be more
completely developed, thereby effecting a higher temperature, and conse-
quently a greater amount of evaporation, while the deposition of soot will be
greatly diminished, if not wholly prevented. After the gases have passed
through the body of the tube chamber, where the tubes are spaced in the
ordinary manner, they are allowed freely to escape to the chimney through
two or three rows of tubes spaced similarly to those at the entrance of the
tube chamber, by which the height of the opening under the bridge leading to
the uptake may be reduced to a minimum.
Thirdly, in the application of circulating tubes or plates to the sides and
crowns of furnaces, by which the surfaces exposed to intense heat are kept
uniformly supplied with a current of water to replace that which is converted
into steam, and which by its velocity over the surface of the metal displaces
the molecules of steam as rapidly as they are formed, and at the same time
prevents the deposition of earthy matter thereon; this I effect by passing

page_text: tubes through all or a portion (as I may find necessary) of the main tubes, the
upper ends extending nearly to the surface of the water, and their lower ends
terminating with one inch or two of the crown of the furnace, or I effect the
same object more completely by plates fixed (as shewn in the Drawing) within
about two inches of the sides and crown of the furnace. Through the inter-
vening space or channel thus formed the water entering at the bottom will
acquire a rapid upward velocity from the heat imparted to it by the heated
surface of the furnace plates and by its intermixture with the steam there
generated. The opening between the plates over the crown of the furnace should
be amply sufficient for the free passage of the combined water and steam.
Fourthly, in the application of vertical water tubes, having their lower ends
closed, in combination with a pendent or inverted bridge, with or without
circulators applied therein. The tubes may be supplied with water through
pipes suspended in them (as shewn in the Drawing), through which water is
conveyed to the lower or closed ends, and thereby prevents them from being
burnt or injuriously heated.
Fifthly, in the application of flat or narrow sheet water cellular chambers
placed over or contiguous to the furnace. The water chambers are open at
the top to the body of the water above them, the ends being closed or open as
most convenient; circulating plates or pipes may be suspended in each
chamber so as to direct the current of the water to the heated surfaces in its
upward 'course.
Sixthly, in the application of a 'furnace door 'divided longitudinally in two
or more parts, so as in opening the door to examine or rake the fire, the
lower part only need be operated, by which arrangement the crown of the
furnace will be much less exposed to detrimental currents of cold air, which,
when admitted, lower the temperature of the gases in the furnace, and greatly
prejudice the evaporation of the 'water.
Seventhly, in the application of vertical water tubes of a diameter not
exceeding one inch and a half and less, and of suitable length, in, combination
with an inverted bridge at the termination of the tube chamber or flue, and
with or without a péndent or inverted bridge at the inner end of the furnace
or thereabouts, by which combination I am enabled beneficially to use tubes
of such length as may be 'readily withdrawn and replaced (when required)
within the boiler, "and by which combination I effect a more complete 'disse-
mination of the heat in the tube chamber throughout the body of the water
in the boiler, and also realize a commensurately increased-evaporation-as-well
as economy of fuel.
---
-Rightht int the onslication Anton tinatal

page_text: foregoing arrangements for effecting increased rapidity of evaporation and
economy of fuel, and construction in boilers of a given capacity.
Having described the objects contemplated by my improvements in the
arrangements herein set forth, the accompanying Drawing and reference will
more clearly demonstrate the nature of the several features of my Invention.
In the reference to the Drawing the same letters apply to similar parts in all
the Figures.
DESCRIPTION OF THE DRAWING
Figure 1 shews an ordinary fire tube marine boiler fitted with an inverted
bridge; Figures 2 and 3 shew vertical water tube boilers, each fitted with an
inverted bridge to the furnace and tube chamber; Figure 4 shews the unequal
spaces of the vertical water tubes; Figures 5 and 6 shew the circulating
plates and tubes applied to furnaces and adaptable to boilers generally;
Figure 7 shews the flat or narrow sheet water cellular chambers as applied to
a marine or other boiler; Figure 8 another form of the same; Figure 9 a
transverse section of the cellular chambers with plate and pipe circulators;
Figures 10 and 11 shew the improved furnace door; Figures 12, 13, 14 shew
the combination of the close ended vertical water tubes with a pendent or
inverted bridge at the termination of the tube chamber.
In Fig. 1, 2, 3, 7, 8, A is the furnace; B is the heating or absorbing
surface in tubes or chambers; C is the inverted bridge (or metal or suitable
material) at the end of the furnace; D is an inverted bridge at the termination
of the tube chamber or flue; E, the uptake to the chimney; F, circulating
tubes or surfaces to promote the circulation of the water from f, and direct it
to the desired point. The tube F in Figs. 2, 3, 7, are surrounded with a water
space crossing the flue.
.
In Figure 4, G is the entrance to the tube chamber, having the tubes
widely spaced, the number of tubes in each row being about one-half of those
In each row in the body of the tube chamber, where they are spaced in the
ordinary manner. H is the end of the tube chamber next to the uptake to
the chimney. The arrows indicate the course of the products of combustion.
The increased spaces at H afford ample room for the developement of the
flame before the gases are checked by their entrance into the tube chamber.
In Fig. 5. and 6 I is a directing plate at each side of the furnace, bent
over the crown, and leaving in the centre an opening the entire length of
the furnace or several smaller openings of ample area for the passage of the
water and steam. Where the crown of the furnace only requires protection,
tube K may be passed through the main tubes to within about two inches of the

page_text: crown of the furnace, and reaching to within about three inches of the surface.
of the water. The tubes and plates may also be used in combination. The
arrows shew the course of the water, by which not only the successive bubbles
or molecules of steam are dislodged from the 'plates as soon as formed, but
any tendency to deposit earthy matter on the plates is thereby prevented.
In Figure 9; L shews, a section of the cellular chambers of boilers in
Figures 7 and 8, fitted with circulators M. N. The chambers may be con-.
structed in various ways as convenience may suggest, and may either be made
with open or closed ends; in any case they should be made so as to admit
of being removed in case of necessity for repairs.
In Figures 10 and 11, 0 is the upper portion of the furnace door, and P.
the lower portion of the same. The latter (P) only should be used for the
ordinary examination and raking of the fire. the portion O being kept closed to
retain the heated gases and prevent their escape from the furnace mouth, and
also to check the influx of cold air to the crown of the furnace, which seriously
impedes evaporation by lowering the temperature of the heating surfaces and
causing a waste of fuel.
In Figures 12, 13. 14, the main tubes, with the circulating tubes within
them, are shewn in section in the three Figures, in which the circulating-tubes-Q
are shewn supplied with water from the less disturbed water of the boiler by
means of connecting tubes R (open at both ends), which conduct the feed to
the bottom of the main tubes, as shewn at large in Fig. 14. The tubes
next the inverted bridge D are shewn of less length than the rest for the con-
venience of the escape of the products of combustion. If they are made of
the same length as the others, sufficient space must be left between them for
the passage of the gases under the bridge D.
Having described the nature and character as well as the objects of my
Invention. I wish it to be understood that I do not claim any of the individual
parts thereof which may have been publicly known or in use for the objects
and purposes herein described, nor do I confine myself to the precise form or
proportions of such parts as herein described, as they may obviously be varied
to suit particular applications without departing from the spirit of my Inven-
tion; but what I claim is the application and use of the several arrangements
herein described separately or in combination, for the purposes and for the
objects herein set forth, that is to say:-
First, I claim the application and use for marine boilers of an inverted or
pendent bridge to the extreme-end-of-the furnace, either before or behind the
ordinary bridge, as circumstances may require, so placed as that the heated
products of combustion may be retained longer in the upper part of the

page_text: combustion.
Secondly, I claim the application and use of unequally spaced tubes in
vertical water tube boilers, the unequal interstitial spaces being disposed
substantially as described, for the purpose of facilitating a better combustion
of the gases, and thereby rendering the tubular surface more effective and less
liable to soot.
Thirdly, I claim the application, and use of circulating plates or tubes,
substantially as described, for the purpose of effecting a more complete circu-
lation of the water at the sides and on the crown of the furnace, whereby the
supply of water is more uniformly maintained, and consequently an increased
evaporation obtained, with the preservation of the heating surfaces from
deposition of earthy matter.
Fourthly. I claim the application and use of close ended vertical water
tubes in combination with an inverted bridge at the termination of the tube
chamber.
Fifthly, I claim the application and use of flat or narrow sheet water
cellular chambers fitted with circulating plates or tubes, substantially as
described.
Sixthly, I claim the application and use of a furnace door divided longi-
tudinally in the manner described.
Seventhly, I claim the application and use of vertical water tubes of
diameters as herein described, in combination with an inverted bridge at the
termination of the tube chamber, with or without a similar bridge at the
extreme end of the furnace.
Eighthly, I claim the application and use of any two or more of these.
several arrangements in combination, for effecting increased rapidity of
evaporation, economy of fuel, and construction and greater durability in
boilers of a given capacity.
In witness whereof, I, the said Arthur Auckland Leopold Pedro
Cochrane, have hereunto set my hand and seal, this Twenty-fourth
day of February, in the year of our Lord One thousand eight hundred
and sixty-five.
ARTHUR A. COCHRANE. (L.S.)