IMPROVEMENTS IN COMPOUND. MARINE STEAM ENGINES
Year: 1884

page_text: We, JOHN WIGHAM RICHARDSON, Shipbuilder and Engineer and JOHN TWEEDY,
Engineer, both of Low Walker, in the County of Northumberland, do hereby
declare the nature of said invention for "IMPROVEMENTS IN COMPOUND. MARINE
STEAM ENGINES" to be as follows:-
Our invention relates to certain improvements in the arrangement, relatively to
each other, of the cylinders and valve chests, with their connecting pipes, of triplo
or quadruple expansion engines by which the following advantages are obtained
over existing systems.
1st Reduction of distances between the centres of cylinders, or 2nd With samo
centres, as in existing systems, to give more available space for valves when placed
between cylinders on line of crank shaft affording better access for examination,
adjustment or repairs.
3rd Facility of disconnection of one or more disabled engines from the efficient
engine or engines.
In carrying out this invention in the case of triple expansion engines, having
three cylinders working on separate cranks, the high pressure or N° 1 cylinder is
placed between the intermediate or No 2 and the low pressure or N° 3 cylinder
reducing the distance between the centres required for the cylinders by half the
difference of the diameters of Nos 1 and 2 cylinders as compared with the ordinary
arrangement when No 2 is placed between Nos 1 and 3 cylinders, and by half the
difference of the diameters of Nos 1 and 3 cylinders, as compared with the less
common arrangement where the No 3 cylinder is placed between Nos 1 and 2
cylinders.
The valves of all the cylinders may be placed either in front or behind, or
forward and aft respectively of the end cylinders, but as it is desirable to have the
parts as direct in action, as simple, and as accessible as possible the valve for N° 1
cylinder is by preference placed between that cylinder and No 2 for which this
arrangement provides sufficient space. This valve is, by preference, a piston valve
accessible both from the top and bottom. The valve for No 2 cylinder is, by
preference, placed forward of its cylinder, and may be either a piston or a slide
valve accessible for repairs and examination on the top, bottom or end, or from all
three places. The low pressure slide valve of N° 3 cylinder may be placed between
its cylinder and No 1, but, by preference, it is placed at the back and has an exhaust

page_text: pipe leading into the centre of the condenser, through the column which supports
No 1 cylinder, or through a separate pipe.
The weight of the valve is balanced by the valve gear acting on the opposite
end of a lever of the first order.
As No 1 engine cylinder is in direct communication with the boiler and as it is
placed aft of N° 2, the latter engine may be disconnected altogether in the case of
a break down and the engine thus at once converted into an ordinary two cylinder
compound engine.
In the case of large triple expansion engines two low pressure or N° 3 cylinders
are used between which are placed N° 1 and 2 cylinders and each cylinder works
on a separate crank. In the case of quadruple expansion engines, having four
cylinders, the high pressure and first intermediate cylinders are placed between
the second intermediate cylinder and the low pressure cylinder, in the case of large
quadruple expansion engines two low pressure and two intermediate cylinders
work on separate cranks, the intermediate cylinders being placed as before between
the low pressure cylinder, and the high pressure cylinder is placed on the top of
one of the intermediate cylinders.
The arrangement of valves and connections for these modifications are similar to
that described for the three cylinder triple expansion engine.
To still further reduce the risk of the total disablement of the machinery at sea,
which increases "pro-tanto" with the increase of working parts.
Provision is made for the ready disconnection of one or more disabled cylinders
as follows:-
A valve or, more simply, a reversible pipe, with blank flange is provided to
convey the steam direct from the boiler to No 2 cylinder in the event of the failure
of No 1. The exhaust pipes from No 1 to No 2 and from No 2 to No.3 are
arranged so that the steam may pass directly from N° 1 to N° 3 in the event of
N° being disabled. A similar. arrangement is provided between N°* 2 and 3 to
allow the exhaust steam from N° 2 to pass directly into the condenser should
No 3 engine fail. As a further precaution the air pump donkey, described in
Mr Tweedy's patent N° 898-1883, is connected to the main condenser on both
sides of the tubes and is available either as an air or circulating pump, or both
combined, should the main pump or pumps become disabled from any cause.
The above description of alternative modes of working in cases of disablement
of either N° 1 or N° 2 cylinder applies of course equally to large triple expansion
engines with two low pressure cylinders, to quadruple expansion engines with four
cylinders or to large engines of that type having also two low pressure cylinders,
certain modifications as to steam and exhaust connections being adopted to suit the
special case.

page_text: We JOHN WIGHAM RICHARDSON, Shipbuilder and Engineer and JOHN TWEEDY
Engineer both of Low Walker in the County of Northumberland do hereby declare
the nature of said invention for "IMPROVEMENTS IN COMPOUND MARINE STEAM
ENGINES and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
"
Our invention relates to certain improvements in the arrangement relatively to
each other, of the cylinders and valve chests, with their connecting pipes, of triple
or quadruple expansion engines by which the following advantages are obtained
over existing systems.
1st Reduction of distances between the centres of cylinders, or,
2nd With same centres as in existing systems, to give more available space for
valves when placed between cylinders on line of crank shaft affording better access
for examination, adjustment, or repairs.
3rd Facility of disconnection of one or more disabled engines from the efficient
engine or engines.
In carrying out this invention in the case of triple expansion engines, having
three cylinders working on separate cranks, the high pressure or No 1 cylinder is
placed between the intermediate or No 2 and the low pressure or No 3 cylinder
reducing the distance between the centres required for the cylinders by half the
difference of the diameters of Nos 1 and 2 cylinders as compared with the ordinary
arrangement when N° 2 is placed between NoB 1 and 3 cylinders and by half the
difference of the diameters of Nos 1 and 3 cylinders as compared with the less
common arrangement where the N° 3 cylinder is placed between Nos 1 and 2
cylinders.
The valves of all the cylinders may be placed either in front or behind, or
forward and aft respectively of the end cylinders, but as it is desirable to have the
parts as direct in action, as simple, and as accessible as possible the valve for
N° 1 cylinder is by preference placed between that cylinder and No 2 for which
this arrangement provides sufficient space. This valve is by preference a piston
valve accessible both from the top and bottom. The valve for No 2 cylinder is by
preference placed forward of its cylinder and may be either a piston or a slide
valve accessible for repairs and examination on the top, bottom, or end, or from all
three places, The low pressure slide valve of N° 3 cylinder may be placed between
its cylinder and N° 1 but by preference it is placed at the back and has an exhaust
pipe leading into the centre of the condenser through the column which supports
No 1 cylinder or through a separate pipe.
The weight of the valve is balanced by the valve gear acting on the opposite end
of a lever of the first order.
As N° 1 engine cylinder is in direct communication with the boiler and as it is
placed aft of N° 2, the latter engine may be disconnected altogether in the case of
a break down and the engine thus at once converted into an ordinary two cylinder
compound engine.

page_text: In the case of large triple expansion engines two low pressure or N° 3 cylinders
are used between which are placed Nos 1 and 2 cylinders and each cylinder works
on a separate crank. In the case of quadruple expansion engines having four
cylinders, the high pressure and first intermediate cylinders are placed between the
second intermediate cylinder and the low pressure cylinder, in the case of large
quadruple expansion engines two low pressure and two intermediate cylinders
work on separate cranks, the intermediate cylinders being placed as before between
the low pressure cylinder, and the high pressure cylinder is placed on the top of one
of the intermediate cylinders.
The arrangements of valves and connections for these modifications are similar
to that described for the three cylinder triple expansion engine.
To still further reduce the risk of the total disablement of the machinery at sea
which increases "pro-tanto" with the increase of working parts, provision is made
for the ready disconnection of one or more disabled cylinders as follows:-
=
A valve or more simply a reversible pipe with blank flange is provided to convey
the steam direct from the boiler to N° 2 cylinder in the event of the failure of N° 1.
The exhaust pipes from N° 1 to N° 2 and from No 2 to N° 3 are arranged so that
the steam may pass directly from N° 1 to N° 3 in the event of N° 2 being disabled.
A similar arrangement is provided between N° 2 and 3 to allow the exhaust
steam from N° 2 to pass directly into the condenser should N° 3 engine fail.
further precaution the air pump donkey described in Mr Tweedys patent N° 898,
AD 1883 is connected to the main condenser on both sides of the tubes and is
available either as an air or circulating pump, or both combined, should the main
pump or pumps become disabled from any cause.
As a
The above description of alternative modes of working in cases of disablement of
either No 1 or No 2 cylinder applies of course equally to large triple expansion
engines with two low pressure cylinders, to quadruple expansion engines with four
cylinders or to large engines of that type having also two low pressure cylinders,
certain modifications as to steam and exhaust connections being adopted to suit
the special case.
DESCRIPTION OF DRAWINGS.
In order that our said invention for improvements in compound marine engines
and the manner of performing the same may be properly understood wo append
hereto 3 sheets of explanatory drawings In these drawings the same numerals
mark the same or like parts where ever they are repeated. The general features
only of the arrangements are shewn and it is to be understood that any parts or
details which are not delineated or described are to be arranged and constructed
as in existing engines or in an analogous manner.
On sheet 1 are. shewn six diagrammatic views. all drawn to the same scale,
looking on the ends of the cylinders of which Figures 1 and 1^ show the proposed
disposition of the cylinders in three cylinder, triple expansion, vertical, horizontal
or diagonal marine engines working on three cranks.-The high pressure cylinder 1
being placed between the intermediate pressure cylinder 2 and the low pressure
cylinder 3.
Figures 2 and 24 show the proposed dispositions of the cylinders in four cylinder
triple expansion marine engines working on four cranks, the high pressure
cylinder 1 being placed between the intermediate cylinder 2 and one of the low
pressure cylinders 3°.
Figures 3 and 4 show (as a comparison of distance between centres) the dis-
positions of the cylinders now generally adopted in triple expansion engines the
figures 1, 2 and 3 denoting respectively the high pressure, intermediate, and low
pressure cylinders.
These diagrams are without reference to the arrangement of the valves and
chests which may be placed between or about the cylinders in any convenient way.
One modification of the arrangement of the chests and valves is shewn by
Figures 5. 6. and 7 sheet 2 where the high pressure valve 4 is placed between the
$

page_text: high pressure and intermediate cylinders 1 and 2. The intermediate pressure
valve 5 at the end of its cylinder 2 and the low pressure, valve 6 at the side of its
cylinder 3.
Figure 11 sheet 3 shews in plan a convenient modification of the valves and
chests of four cylinder triple expansion engines having the cylinders arranged
according to this invention. The high pressure valve 4 is shewn placed between
the low pressure and high pressure cylinders 30 and 1, the intermediate pressure
cylinder valve 5 between the cylinders 2 and 1 and the low pressure valves 6 and 6ª
at the sides of their cylinders 3 and 30.
The weight of the low pressure valves in each case is practically balanced by the
weight of the valve gear acting on the opposite end of the lever 16.
To facilitate the disconnection of one or more cylinders the steam and exhaust
connections are bolted to the main castings and are either made in interchangeable
or special pipes are provided. Modifications of the arrangement are shewn by
Figures 5. 6, 7. 8, 9 and 10 sheet 2 and hy Figures 11. 12. and 13 sheet 3.
1
In the event of the disablement of the intermediate cylinder 2, or any of its
parts, necessitating its disconnection, one of the pipes, say the pipe 9 (or part of it)
which in ordinary working conveys the exhaust steam from the chest 5 to the
chest 6, is removed and the pipe 8 (or part of it) or a pipe made specially for the
purpose, depending upon the way the details are worked out, is used to connect
the chest 4 to the chest 6 as shewn by Figure 8 sheet 2, and Figure 13 sheet 3, the
engine will now work as an ordinary duplex expansion engine where 1 is the high
pressure cylinder and 3 the low pressure cylinder or 3 and 3ª in fig 13.
In the event of the disablement of the high pressure cylinder 1, the pipe 8,
which in ordinary working conveys the exhaust steam from the chest 4 to the
chest 5, or a similar pipe is used to connect the main steam stop valve 7 with
the chest 5, one of the blank flanges 13 or 14 (Figures 7, 8, and 10 sheet 2, and 11
and 13 sheet 3) is moved to 15 and the system becomes an ordinary duplex
expansion engine where 2 is the high pressure cylinder and 3 the low pressure
cylinder as shewn by Figure 9 sheet 2, or 2 the high pressure and 3, 3a the low
pressure cylinders as shewn by Figure 12 Sheet 3.
In the case of failure of the low pressure cylinder 3 of three cylinder triple
expansion engines the exhaust steam is conveyed direct to the condenser from the
chest 5 by the pipes 9 and 11.
The engine now becomes an ordinary duplex expansion engine where is the
high pressure cylinder and 2 acts as a low pressure cylinder as shewn by Figure 10,
sheet 2.
In the event of the failure of one of the low pressure cylinders 3 or 3ª in the
four cylinder arrangement a part (17 or 17ª as the case may be) of the exhaust
pipes connecting the chests 5 and 6 and the corresponding exhaust pipe 11 or 11ª
(Figure 11 sheet 3) are removed and blank flanges fitted. The engine will then
work as a three cylinder triple expansion engine where 1 is the high pressure,
2 the intermediate pressure, and one of the cylinders 3 or 3º (as the case may be)
the low pressure cylinder. Figures 14 and 15 sheet 3 show modifications of
the arrangement as applied to engines whose cylinders are disposed in the
ordinary way.
All, or part only of these provisions may be adopted and the pipes may be made
to interchange or combine with special pipes in a variety of ways and valves inay
be used in conjunction with the pipes; still preserving the interchangeable principle
herein before described.
To facilitate the starting of marine engines more especially when one of the
cylinders is disconnected and as a precaution against total disablement at sea
through the failure of the main air pump, the auxiliary donkey usually fitted on
board ship has its valves and connections arranged so that it may act as a
combined air and circulating pump or as an air pump only being connected to the
vacuum side of main condenser, or as a circulating pump only, as described and

page_text: arranged for use in connection with an auxiliary condenser or distiller in
Mr Tweedy's Patent 898, A.D. 1883.
Although our specification refers to the application of our invention to quadruple
expansion engines having four or more cylinders we have not shown by drawings
nor described in detail how it may be applied in such cases as it is to triple
expansion engines that we consider it specially important.
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
First. With the object of shortening the distance between the centres of
cylinders and facilitating the arrangement of the valve chests and connections,
with special reference to the ready disconnection of a cylinder; placing the high
pressure cylinders of triple expansion marine engines, whose cylinders work on
separate cranks, between the low pressure cylinder and the intermediate pressure
cylinder substantially as shewn and described.
Second. Arranging the valves and connections of triple expansion marine engines,
whose cylinders work on separate cranks, in such a way that a cylinder or
cylinders may be very readily and quickly disconnected substantially as shewn
and described.
Third. As a precaution against difficulty in starting engines or accidental
disablement of the main air pump, connecting the combined donkey (described in
Mr Tweedy's patent No 898, A D 1883) to the vacuum side of the main condenser
substantially as herein before described.