IMPROVEMENTS RELATING TO COMPOUND STEAM ENGINES AND BOILERS to be as follows
Year: 1885

page_text: We, WILLIAM HARGREAVES and WILLIAM INGLIS, of Soho Iron Works Bolton,
in the County of Lancaster, Engineers, do hereby declare the nature of my
said invention for "IMPROVEMENTS RELATING TO COMPOUND STEAM ENGINES AND
BOILERS to be as follows, that is to say:
"
Our said Invention has for its object to obtain increased economy of fuel in
connection with steam engines, by applying the heat in an improved manner; my
improvements also having other practical advantages.
In carrying out my Invention I employ what may be termed a compound system
of boilers in combination with compound steam engines working with two or more
stages of expansion. In the case of a double-expansion engine working with one
or more high-pressure cylinders and one or more low-pressure cylinders we employ
two distinct boilers or sets of boilers. A high-pressure boiler supplies steam to
the high-pressure cylinder and the exhaust steam from that cylinder passes into
the low-pressure boiler which serves the purpose of a receiver and supplies the
low-pressure cylinder, the exhaust steam from this last passing to a condenser.
Water is fed, by preference, first into the low-pressure boiler, and from that boiler
into the high-pressure boiler.
The most intense heat of the furnace is first applied to the high-pressure boiler,
and the fire gases are made to act subsequently on the low-pressure boiler. It will
be evident that the heat of the fire gases will be more completely utilised than
when the entire boiler is subjected internally to the high-pressure and has necessarily
the highest heat applied to it; as after the fire gases have given all the heat they
can to the high-pressure boiler, further quantities of heat are absorbed from them
by the low-pressure boiler.
When applying our improved system in the case of engines working with more
than two stages of expansion a corresponding number of distinct boilers or sets of
boilers is employed. Thus with triple expansion engines having one or more high-
pressure cylinders, one or more intermediate cylinders, and one or more low-pressure
cylinders there will be three distinct boilers or sets of boilers.
With our improved arrangements an increased efficiency and regularity of action
will be obtained, in consequence of the steam acting in the interinediate and low-
pressure cylinders being maintained of a more uniform pressure during admission
and up to the points of cut off than occurs in existing engines.
Dated this antith
100-
EDMUND HUNT,
Applicants' Agent.

page_text: .
Improvements relating to Compound Steam Engines
and Boilers.
We, WILLIAM HARGREAVES and WILLIAM INGLIS, of Soho Iron Works, Bolton,
in the County of Lancaster, Engineers, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement, that is to say :—
Our said Invention has for its object to obtain increased economy of fuel in
connection with steam engines, by applying the heat in an improved manner; our
improvements also having other practical advantages.
In carrying out our Invention we employ what may be termed a compound
system of boilers in combination with compound steam engines working with two
or more stages of expansion. In the case of a double-expansion engine working
with one or more high-pressure cylinders and one or more low-pressure cylinders,
we employ two distinct boilers or sets of boilers. A high-pressure boiler supplies
steam to the high-pressure cylinder, and the exhaust steam from that cylinder
pases into the low-pressure boiler, which serves the purpose of a receiver and supplies
the low-pressure cylinder, the exhaust steam from this last passing to a condenser.
Water is fed by preference, first into the low-pressure boiler, and from that boiler
into the high-pressure boiler.
The most intense heat of the furnace is first applied to the high-pressure boiler,
and the fire gases are made to act subsequently on the low-pressure boiler. It
will be evident that the heat of the fire gases will be more completely utilised
than when the entire boiler is subjected internally to the high pressure and has
necessarily the highest heat applied to it; as after the fire gases have given all the
heat they can to the high-pressure boiler, further quantities of heat are absorbed
from them by the low-pressure boiler.
And in order that our said Invention and the manner of performing the same
may be properly understood we hereunto append two sheets of explanatory
drawings to be hereinafter referred to and representing two examples of the
practical application of our improvements.
Figure, 1, on sheet, 1, of the accompanying drawings is a sectional plan showing
one arrangement of combined compound boilers and compound engines. Figure, 2,
on sheet, 2, is a plan, figure, 3, is a vertical longitudinal section and figure, 4, is an
end elevation (the smoke box door being removed) showing a second arrangement.
In these drawings the same reference letters and numerals are used to mark the
same or like parts wherever they are repeated.
In the arrangement shown on sheet, 1, of the drawings the engine comprises one
high-pressure cylinder, C1, and one low-pressure cylinder, C2, these cylinders
being placed horizontally and combined tandem fashion, the pistons being on one
rod, R, connected to a single crank on the main shaft S.
There are two
boilers B1, B2, one, B1, being for producing high-pressure steam which is led
from it by a pipe, P 1, to the valve casing of the high-pressure cylinder, C, 1. The
exhaust steam from the high-pressure cylinder, C1, is led by a pipe, E 1, to the

page_text: second boiler, B2, in which the steam is at a lower pressure than in the first
boiler, B 1, and from the second boiler, B2, the steam is led by a pipe P 2, to the
valve casing of the low-pressure cylinder, C2, the exhaust pipe, E 2, from this
cylinder being below the cylinder.
The boilers, B1, B2, may be of various constructions, those represented in figure, 1,
being short horizontal cylindrical boilers with flue tubes through them. The first
boiler, B 1, is subjected to the direct furnace heat and the most intense heat of the
fire gases whilst the second boiler, B 2, is acted on by the fire gases after they have
passed through the first boiler. There is an enclosed space or flue, A between the
boilers through which the fire gases pass on their way from the first to the second
boiler. After leaving the second boiler, B2, the fire gases pass into flues, F,
arranged so that the gases may be led either through feed-heating apparatus, H, or
directly to the chimney, K. The feed water is by preference pumped first into
the second boiler, B 2, and from that boiler into the first boiler, B 1.
In the arrangement shown on sheet, 2, of the drawings. The combination of
boilers, B1, B2, and engine cylinders, C1, C2, is of what is known as the
"locomotive" type. The two boilers, B1, B2, are connected by an intermediate
chamber, A, so as to form as it were one boiler divided into two distinct com-
partments. The cylinders, C1, C2, are placed side by side under the smoke-box
end of the boilers, and are connected to separate cranks on the shaft, S. The
pipe connections and other details are substantially the same as in the arrangement
shown on sheet, 1, of the drawings, and hereinbefore described.
When applying our improved system in the case of engines working with more
than two stages of, expansion, a corresponding number of distinct boilers or sets of
boilers may be employed. Thus with triple-expansion engines having one or more
high-pressure cylinders, one or more intermediate cylinders, and one or more low-
pressure cylinders, there may be three distinct boilers or sets of boilers; or only
two boilers or sets of boilers may be used with triple-expansion or quadruple-
expansion engines, each boiler or set of boilers supplying steam for one or two
stages of expansion.
With our improved arrangements an increased efficiency and regularity of action
will be obtained, in consequence of the steam acting in the intermediate and low-
pressure cylinders, being maintained of a more uniform pressure during admission,
and up to the points of cut-off than occurs in existing compound engines.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed we declare that what
we claim is
The combination with compound steam engines working with two or more
stages of expansion, of compound boilers or two or more boilers or sets of boilers
working with different pressures, the said engines and boilers operating in concert
substantially in the manner herein before described.
Dated this ancntranth day of Fahmuary 1886
EDMUND HUNT,
Applicants' Agent.