IMPROVEMENTS IN STEAM ENGINES FOR SHIPS OF WAR
Year: 1876

page_text: LETTERS PATENT to Alexander Carnegie Kirk, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVEMENTS IN
STEAM ENGINES FOR SHIPS OF WAR."
Sealed the 21st October 1876, and dated the 18th August 1876.
PROVISIONAL SPECIFICATION left by the said Alexander Carnegie Kirk at
the Office of the Commissioners of Patents on the 18th August 1876.
ALEXANDER CARNEGIE KIRK, of Glasgow, in the County of Lanark, North
Britain, Engineer. "IMPROVEMENTS IN STEAM ENGINES FOR SHIPS OF WAR."
This Invention relates to the class of engines with which many ships of war are
now fitted, and which under ordinary circumstances work on the compound or
high and low pressure system with an initial or boiler pressure considerably above
that of the atmosphere; and the object of the improvements is to enable the
engines to be satisfactorily worked with an initial pressure as low as that of the
atmosphere or even lower.
The improved arrangements will admit of a steam ship of war with engines of
the kind referred to being got under way much sooner after the first lighting of
the fires than would otherwise be possible; and will give control over the
movements of the ship when only a low pressure of steam is desirable or available.
•
It has already been shown how a ship of war having compound engines can be
provided with arrangements of various kinds admitting of a largely increased power
being developed up on an emergency, as for example, by the late John Elder, in the
Specification of Letters Patent granted to him and dated 14th March 1866,
(No. 759), the object being obtained in the arrangements referred to by means of
valves admitting steam of the initial or boiler pressure to the low-pressure cylinder
or cylinders; and in carrying out the present Invention such arrangements are also
used, but there are in addition combined with them certain arrangements connected
with the condenser to admit of the objects now contemplated being carried out.
The valve arrangements in connection with the cylinders are by preference of an
improved kind, and comprise in the case of each high-pressure cylinder a valve
chest to which steam has access directly from the boiler, and in which there are a
slide valve and a port face having three ports. The middle one of the three ports
communicates with the exhaust port of the high-pressure cylinder, whilst one of the

page_text: outer ports communicates with the valve casing of the low-pressure cylinder or
cylinders, and the other with the condensor. The valve has a cavity for putting the
middle port in communication with either of the other two, and it is formed with a
cover which closes the condenser port when the other two ports are in com-
munication, as happens when the engines are working on the compound system.
When the valve is shifted it puts the exhaust port of the high-pressure cylinder in
communication with the condenser and uncovers the port leading to the low-
pressure valve casing, so as to admit the initial or boiler pressure directly
thereto.
The condenser is by preference of the surface condensing kind; and in order
that the engines may work satisfactorily as non-compound at the low pressure
contemplated it is necessary that a good vacuum in the condenser can be obtained
independently of the working of the main engines. For this purpose the circulating
pumps are worked by a suitable independent engine which is to be kept constantly
at work whether the main engines are going or not, and which may be compound
and arranged like the main engines for working as non-compound when required.
The independent engine is by preference arranged to drive at least two circulating
pumps, one at least of which pumps is a bucket pump or otherwise suitable for
acting as an air pump.
When the main engines are working either as compound or non-compound all
these pumps will pump cold water through the condenser tubes; but while the
main engines are being worked as non-compound and at a low pressure, whenever
they are stopped on any occasion, valves in connection with the pump or pumps
capable of acting as air pumps are adjusted so as to make such pumps draw from
the condenser in order to maintain a vacuum which will enable the main engines to
be again started; then as soon as the main engines are re-started the valves
referred to are reversed, so that all the pumps may again act as circulating
pumps.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Carnegie Kirk in the Great Scal Patent Office on the 16th
February 1877.
ALEXANDER CARNEGIE KIRK, of Glasgow, in the County of Lanark, North
Britain, Engineer. “IMPROVEMENTS IN STEAM ENGINES FOR SHIPS OF WAR."
My said Invention relates to the class of engines with which many ships of war
are now fitted, and which under ordinary circumstances work on the compound or
high and low pressure system, with an initial or boiler pressure considerably above
that of the atmosphere; and the object of my improvements is to enable the
engines to be satisfactorily worked with an initial pressure as low as that of the
atmosphere or even lower.
My improved arrangements will admit of a steam ship of war with engines of
the kind referred to being got under way much sooner after the first lighting of the
fires than would otherwise be possible; and will give control over the movements of
the ship when only a low pressure of steam is desirable or available.
It has already been shown how a ship of war having compound engines can be
provided with arrangements of various kinds admitting of a largely increased
power being developed upon an emergency, as for example, by the late John Elder,
in the Specification of Letters Patent granted to him and dated 14 March 1866,
(No. 759), the object being attained in the arrangements referred to by means of
valves admitting steam of the initial or boiler pressure to the low-pressure cylinder
or cylinders; and in carrying out my present Invention such arrangements are also
used, but there are in addition combined with them certain arrangements connected
with the condenser to admit of the objects now contemplated being properly
carried out.

page_text: The valve arrangements which I by preference adopt in connection with the
cylinders are of an improved kind, and a modification of them is shown on the
accompanying Sheet of explanatory Drawings.
Figure 1 of these Drawings is a plan with the cover of a valve casing removed;
and Figures 2 and 3 are vertical sections as at right angles to each other.
The same reference numerals are used to mark the same parts in all the
Figures.
The modification delineated is designed for engines having horizontal cylinders,
and a part of the high-pressure cylinder 4 is shown with a vertical port face 5 at
one side of it. The steam from the boiler has access by a pipe 6 and
passage 7 to
the high-pressure port face 5, and the exhaust steam from the high-pressure
cylinder 4 proceeds by a passage 8 to a casing 9, in the upper part of which there
is a port face 10 and a slide valve 11. A. cover 12 encloses the space in which the
valve 11 works, and steam direct from the boiler has access to that space by a port
or passage 13. The port face 10 has in it three ports 14, 15, 16, the middle port 15
communicating by the passage 8 with the exhaust port of the high-pressure
cylinder 4, whilst one 14 of the ports communicates by a passage 17 and pipe 18
with the valve casing or casings of the low-pressure cylinder or cylinders. The
remaining port 16 communicates with the condenser by a passage 19 and pipe 20.
The valve 11 has a cavity for putting the middle port 15 in communication with
either of the other two 14, 16, and it is formed with a cover 21 which closes the
condenser port 16 when the other two ports 15, 14, are in communication as
happens when the engines are working on the compound system, and as shown in
full lines in Figure 2. When the valve 11 is shifted it puts the middle port 15, and
consequently the exhaust port of the high-pressure cylinder, in communication with
the condenser by the port 16, and it uncovers the port 14 leading to the low-
pressure valve casing so as to admit the initial or boiler pressure directly thereto. The
shifted position of the valve 11 is indicated by dotted lines in Figure 2, and full and
dotted arrows indicate the respective directions of the steam in the two positions of
the valve. The valve is shifted by means of a screw spindle 22 fitted with a pointer
which shows on a plate in what position the valve is.
In engines having two or more sets of high and low pressure cylinders, one
valve (11) may when convenient serve for changing the action of the entire engines
from compound to non-compound, and vice versa.
The condeser is by preference of the surface condensing kind; and in order that
the engines may work satisfactorily as non-compound at the low pressure con-
templated it is necessary for a good vacuum in the condenser to be obtainable
independently of the working of the main engines. For this purpose I arrange a
suitable independent engine for working the circulating pumps. Such engine inay
be compound and arranged like the main engines for working as non-compound
when required, and are kept constantly at work whether the main engines are
going or not for any time during which the main engines may have to work as
non-compound at the low pressure. The independent engine is arranged to drive
two or more circulating pumps, and one at least of such pumps is made a bucket
pump or otherwise suitable for acting as an air pump.
When the main engines are working either as compound or non-compound all
these pumps will pump
cold water through the condenser tubes; but whilst the
main engines are being worked as non-compound and at a low pressure, then
whenever they are stopped on any occasion valves in connection with the pump or
pumps capable of acting as air pumps are adjusted so as to make such pumps draw
from the condenser in order to maintain a vacuum which will enable the main
engines to be again started. As soon however as the main engines are restarted
the valves referred to are reversed, so that all the pumps may again act as circulating
pumps.
The practical engine constructor will have no difficulty in carrying out the
described arrangements in various cases, it being simply necessary to provide
passages or pipes and stop valves of any suitable kind in connection with the

page_text: circulating pump or pumps intended to be used for drawing from the condenser in
addition to the passages by which the circulating water passes to and from it or
them.
Having thus particularly described my said Invention, and the manner of
performing the same, I have to state that I do not restrict myself to the precise
details herein described or delineated, but that what I believe to be novel and original,
and claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,―
1. The arranging of compound engines of war ships so as to be workable as non-
compound and at low pressure by applying to them any suitable arrangement of
valve which can be adjusted to lead steam directly from the boiler to the low-
pressure cylinder or cylinders, and combining with such arrangement an independent
circulating engine arranged so as to be available for obtaining a vacuum in the
condenser of the main engines, substantially as and for the purposes herein-before
described.
2. The combining of a slide valve and passages for converting compound engines
of war ships into non-compound, substantially as herein-before described with
reference to the accompanying Drawings.
3. The arranging of independent circulating engines in connection with the main
engines of war ships, one or more of the pumps of such circulating engines being
provided with passages or pipes and stop valves admitting of their use for obtaining
à vacuum in the condenser of the main engines, substantially as and for the
purposes herein-before described.
In witness whereof, I, the said Alexander Carnegie Kirk, have hereunto set
my hand and seal, this Fifteenth day of February, in the year of our Lord
One thousand eight hundred and seventy-seven.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
ALEXANDER C. KIRK.. (LS.)