AN IMPROVED COMBINATION AND ARRANGEMENT OF MARINE BOILERS FOR THE ECONOMY OF FUEL, AND OCCUPYING LESS HORIZONTAL SPACE IN THE SHIP THAN ORDINARY BOILERS OF THE SAME POWER
Year: 1875

page_text: LETTERS PATENT to Charles Cottew, of South Shields, in the County
of Durham, for the Invention of "AN IMPROVED COMBINATION AND
ARRANGEMENT OF MARINE BOILERS FOR THE ECONOMY OF FUEL, AND OCCUPYING
LESS HORIZONTAL SPACE IN THE SHIP THAN ORDINARY BOILERS OF THE SAME
POWER."
Sealed the 12th April 1876, and dated the 2nd November 1875.
PROVISIONAL SPECIFICATION left by the said Charles Cottew at
the Office of the Commissioners of Patents, with his Petition, on
the 2nd November 1875.
I, CHARLES COTTEW, of South Shields, in the County of Durham, do
hereby declare the nature of the said Invention for "AN IMPROVED
COMBINATION AND ARRANGEMENT OF MARINE BOILERS FOR THE ECONOMY OF FUEL,
AND OCCUPYING LESS HORIZONTAL SPACE IN THE SHIP THAN ORDINARY BOILERS OF
THE SAME POWER," to be as follows:-
The object of my Invention is to provide an arrangement of boilers
that shall occupy less horizontal space, consume less fuel, and yet be as

page_text: efficient as any ordinary marine boiler of the same power. To this end
I place say, two ordinary Cornish boilers side by side, and above these
I set a cylindrical multitubular boiler. Each of the lower boilers have
two furnaces with cylindrical flues running through to the end.
The upper or multitubular boiler has no means of generating heat,
but the flames and heated gases from the furnaces below after passing
through their respective smoke tubes commingle in an uptake or
combustion chamber which is surrounded on three sides by the feed
water, the fourth side representing the ends of the three boilers, and
forms a communication between the four furnaces (thero being two
furnaces in each of the lower boilers as already mentioned), and the
tubes of the multitubular boiler through which the flames and heated
gases pass conveying heat thereto and generating steam thereby before
entering the chimney or funnel.
Pipes with suitable valves connect the steam spaces of each boiler
with one another. The water spaces are similarly united by pipes and
self-acting feed valves, so that the feed water after flowing round the
three sides of the combustion chamber and deriving heat therefrom,
enters the upper boiler, thence admitted through the self-acting feed
valves into the lower boilers. This method of feeding prevents the
incrustation of the small tubes in the tubular boiler, the deposit of lime
or salt being carried downward into the lower boilers, whence it can be
more easily removed.
A great saving of fuel will be found to result from the above com-
bination and arrangement of boilers, by the more perfect combustion of
the smoke and gases in the large uptake or combustion chamber at the
rear of the boilers and around which the feed water flows; the boilers
can be made shorter; this gives more stowage room for cargo, and the
great extent of water surface prevents the possibility of priming.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of November, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Charles Cottew, Her special
licence that I, the said Charles Cottew, my executors, administrators,
and assigns, or such others as I, the said Charles Cottew, my exe-
cutors, 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 "AN
IMPROVED COMBINATION AND ARRANGEMENT OF MARINE BOILERS FOR THE ECONOMY
OF FUEL, AND OCCUPYING LESS HORIZONTAL SPACE IN THE SHIP THAN ORDINARY
BOILERS OF THE SAME POWER," upon the condition (amongst others) that I,
the said Charles Cottew, my 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
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 Charles Cottew, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement in writing, reference being had to the accom.
panying Drawing and to the letters and figures marked thereon (that is
to say) :-
The object of my Invention is to provide an arrangement of boilers
that shall occupy less horizontal space, consume less fuel, and yet be as
efficient as any ordinary boiler of the same power.
To this end I place,
say, two ordinary Cornish boilers side by side, and above them I set a
cylindrical multitubular boiler. The lower boilers may each have, as is
usually the case, two furnaces with smoke tubes running through to.
the end.
The upper or multitubular boiler has however no means of generating
heat, but at the rear end of the boilers I construct what may be called

page_text: an up-take or combustion chamber, which forms a passage, smoke way,
or flue from the furnaces in the lower boilers to the smoke tubes in the
upper boiler. This uptake or combustion chamber is surrounded on
the top and three sides with a water space (the fourth side formed by
the ends of the boilers), and becomes an excellent generator of steam,
and as the smoke and heated gases from the furnaces commingle therein
before passing through the smoke tubes of the upper boiler, it also
becomes in part a smoke consumer.
Pipes with suitable valves connect the steam spaces of each boiler
with one another. The water spaces are similarly united by means of
pipes and feed valves, so that the feed water after flowing round the
sides of the combustion chamber and deriving heat therefrom, enters
the upper boiler, thence admitted through the feed valves into the lower
boilers. This method of feeding the boilers with water prevents the
small smoke tubes which are so difficult to clean becoming incrustated
with lime or salt, the deposit being carried down to the lower boilers,
whence it can be readily removed.
The boilers may also be fed by injecting in the usual way the feed
water into the upper boiler, where it would receive the heat passing
through the numerous small smoke tubes, passing from thence through
suitable pipes to the water space of the uptake or combustion chamber,
and from thence to the lower boilers by means of regulating cocks or
valves.
A great saving of fuel will be found to result from the above com-
bination and arrangement of boilers, and by the more perfect combustion
of the smoke and gases in the large uptake or combustion chamber at
the rear of the boilers, and around which the feed water flows.
My improvements also admit of the boilers being made shorter than
usual, thus, giving more stowage room for cargo or coal, and the steamer
made capable of making longer voyages without recoaling. The great
extent of water surface prevents the possibility of priming.
In Figure 1 of the accompanying Drawing I have shown a front view
partly in elevation and partly in section of my improved combination
and arrangement of marine boilers.
Figure 2 is a longitudinal section on line A*, B*, (Figure 1), and
Figure 2 is a longitudinal elevation of the same.

page_text: Figure 3 is an end view partly in section, shewing on the one side the
uptake or combustion chamber in section, on the other side the feed
water space surrounding it in elevation.
Figures 4 and 5 are diagrams of my Invention modified to suit
particular situations, purposes, or conveniences.
Figures 6 and 7 are a modified form of uptake or combustion
chamber, Figure 8, being a plan of the top, and Figures 9, 10, and 11,
sections respectively on lines A, B, and C, see Figure 7. For the sake
of convenience Figures 6 to 11 inclusive are drawn to a reduced scale.
In all these Figures A, A, are the Cornish boilers surmounted by the
multitubular boiler B; a, a, a, a, are the furnaces or flues, the flames
and smoke from which comingle in the uptake E and ascending pass
through the small tubes b, b, b, of the upper boiler into the smoke
box C, and out of the chimney or flue D, see Figures 1, 2, and 3; F, F,
is the water space surrounding the top and three sides of the combustion
chamber E, and supplied by the valve i; G, G, are the water spaces of
each boiler, and communicate one with the other by means of pipes g, g,
provided with feed valves; H, H*, are the steam spaces likewise com-
municating with one another by means of pipes h, h, and valves h*,
h*.
Each boiler is provided with an ordinary safety valve, blow-off cocks,
water gauges, man-holes, and other necessary furniture and appendages
not shown on the Drawing. The uptake and feed water space are also
constructed with suitable man-holes and cocks for cleansing and
repairing the same.
In Figure 6, a, a, a, a, are the smoke tubes from the four furnaces
entering the combustion chamber E. The bottom of the chamber and
the ends of the boilers are here shown covered with fire-brick lining;
F, F, is the feed water space. In Figures 7, 9, 10, and 11, t, t, are stay
bolts to give stability to the structure; E is the combustion chamber,
and F, the feed water space.
The mode of action would be as follows:-The valve i admits water
into the water space F, where it is heated by the flames and gases from
the furnaces a, a, a, a, Figure 1, and passing along the pipe k, Figure
2*, or its accessory k*, Figure 2, (which is inserted in the under side of
the boiler to ensure complete circulation of the water,) the feed water
enters the upper boiler and receives the hoat that is passing through the

page_text: small tubes b, b. From this boiler the water is admitted through
regulating feed valves j, j, and by means of the pipe 9 (which is fitted
with a self-acting feed valve as shown to a large scale in Figure 12) into
the lower boilers, where it acquires great heat and steam generative
power from the fierce furnaces a, a, a, a. Steam is now rapidly pro- 5
duced, filling the steam space H, see Figure 1, from whence the power
to drive the engine is derived by means of the steam pipe with which
both, or in cases where more than two lower boilers are used, as shown
in Figure 5, then all the lower boilers are provided. Each of theso
steam pipes are fitted with a suitable valve m, m, Figures 1 and 2, com- 1
municating with the connecting pipe n leading to the supply pipo to
the engine (o).
In Figure 12 I have shown to a large scale the self-acting feed valve
that is fitted to the end of the pipe g (Figures 1 and 2); W, L, is the
water line in the boiler, and r, the float that opens or shuts the conical 1
valse 8, as the water line varies, according as feed or consumption
predominates.
No deposit or sediment is formed in the upper boiler, where it would
be with difficulty removed, but the lime, salt, and mud are carried down
by the flowing water into the lower boilers, and therefrom readily 2
removed in the ordinary way, for which purpose the usual man-holes
(not shown in the Drawing) are provided.
To recapitulate the advantages derived from the above arrangement
may be briefly stated,-
1st. A great economy of fuel arising from the general arrangement 2
and combination of the boilers, and from the more perfect combustion of
the smoke and gases in the combustion chamber, consequently the
vessel is able to take longer voyages without recoaling.
2nd. Greater simplicity, durability, stability, and efficiency than
ordinary boilers.
3rd. Occupying as it does less horizontal space in a steam vessel more
cargo room is obtained, or a greater quantity of coal may be stowed for
a long voyage.
3
4th. Less skill and attention is required in the management, the self-
acting feed valves always keeping the water in the lower boilers at the 3
proper height.

page_text: 5th. The property of not depositing scales on the tubes of the upper
boilers, nor on the plates of the feed water chamber, dispenses with the
necessity of a surface condenser, thus all the evils and costs arising from
such employment is entirely avoided, and the durability of the boilers
increased.