Improvements in Steam Pumps,
Year: 1899

page_text: Date of Application, 12th May, 1899-Accepted, 24th June, 1899
COMPLETE SPECIFICATION.
Improvements in Steam Pumps,
We, PHILIP ELIOT HODGKIN and WALTER MAY, Engineers, both of the
Pulsometer Engineering Company, Limited, of 63, Queen Victoria Street, in the
City of London, 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: —
steam
one
as
we
'shall
now
to
This invention has reference to an improved construction and arrangement of
describe with reference
compound
pump
views
the accompanying illustrative drawings wherein Figs. 1 and 2 are
central vertical
at right angles to
another, Fig. 1 being in
section and Fig. 2 in side elevation, showing the improved pump. Fig. 3
shows in vertical section, and to a larger scale than Figs. 1 and 2, an auxiliary
valve chest and valve together with the adjacent main valve chest of the high pres
sure cylinder. Fig. 4 is a horizontal section on the line a a of Fig. 3. Fig. 5
shows partly in side elevation and partly in vertical section, and also to a larger
scale than Figs. 1 and 2, the pump barrel and its valve chest. Figs. 6 to 9 are
detail views.
In the arrangement shown, the high pressure cylinder 1 and low pressure
cylinder 2 are arranged vertically one over the other with a hollow distance piece 3
between their adjacent ends and are supported by vertical side rods 4 over a vertical
7 and 8 are the high and
pump barrel 5 provided with a suitable foot or base (.
low pressure pistons connected together by a common rod 9 that works through an
intermediate stuffing box 9. 10 is the pump piston fixed to the pump rod 10%.
To admit of this pump rod being made short and so that it and the pump piston
can be readily withdrawn from the pump barrel, the low pressure piston 8 is pro-
vided with a pair of piston rods 9b that work through a pair of stuffing boxes 9°
in the lower end of the cylinder 2 and are connected at their lower ends to a cross-
head 11 to the central portion of which the upper end of the pump rod 10" is
detachably connected. This arrangement is specially advantageous in cases where
the pump is to be used in a limited space, as for example between decks in a ship,
where there is not room to insert and withdraw a single rod common to the engine
and pump pistons.
The high pressure cylinder 1 is provided near its lower end and to one side
thereof, with a main valve chest 12 that is arranged to be placed in communication
with the upper and lower ends of the cylinder 1 by steam passages 13 and 13" the
lower of which is provided,, as usual, with a small branch passage 13b for admit-
ting steam to the lower side of the piston 7 when the same covers the lower steam
passage 13. The two passages 13, 13ª are controlled by a pair of high pressure
piston valves 14, 14°, the annular space between which is in constant communica-
tion with a centrally arranged steam inlet passage 15 and pipe 15" The pair of piston
valves 14, 14 are connected through intermediate distance pieces to a pair of end
pistons 16, 16, the combined valves and pistons being fixed to a common rod 17
arranged to work through stuffing boxes in the ends of the valve chest 12. The
valve chest 12 is formed with passages 12" whereby steam that has entered either

page_text: of the annular spaces 18 between the piston valves 14, 14 and the adjacent
pistons 16, 10, from the corresponding passage 13 or 13ª can pass to a common
outlet 12b. The valve chest 12 is also formed with passages 19, 19" (Fig. 3) where-
by each of its ends can be placed in connection with the interior of an auxiliary
valve chest 20, the said passages 19, 19" being controlled by a slide valve 21 which
may be a flat circular slide valve as shown, or a double piston valve, and is worked
by a rod 22. The valve chest 20 is in constant communication with the steam
inlet 15 through a suitable passage 20" (Fig. 4) and is provided with an exhaust
port or passage 20 that is adapted to be placed in communication with each of
the passages 19 and 19" alternately by movement of the valve 21, and is in con-
stant communication with the exhaust passage 12".
The low pressure cylinder 2 is provided near its lower end, and to one side
thereof, with a valve chest 23 that is adapted to be placed in connection with the
upper and lower ends of the said low pressure cylinder by passages 24, 24ª respec-
tively, that are controlled by a pair of piston valves 25, 25" fitted to slide in the
said valve chest 23 and connected to the main valve rod 17, the central portions
of the valve chest 23 being connected through a passage 26 to an external exhaust
pipe 27 leading from the exhaust outlet 12 of the valve chest 12. The end
portions of the valve chest 23 communicate with a low pressure exhaust outlet
pipe 28.
The valves 14, 14" with pistons 16, 16 may be built up of spring rings and
distance pieces in the ordinary manner. To admit of such valves and pistons
being securely fixed in place on the valve rod from the exterior of the valve chest,
thus dispensing with internal nuts or other fastenings and obviating the dis-
advantages attending the use of such fastenings, and also to enable the total steam
pressure against the lower side of the combined valves and pistons to exceed
the total pressure against the upper side thereof and thus balance, or partly
balance, the weight of the valves and attached parts, the valves and pistons may,
as shown, be forced against a seat 17", preferably conical, on the valve rod 17 by a
sleeve 16b that surrounds the valve rod, extends through the upper stuffing box 164,
and has an external diameter greater than the diameter of that portion of the valve
rod which works through the lower stuffing box 16°. The said sleeve is screwed
onto the valve rod 17 so as to force its inner end, which may advantageously be
provided with a flange or collar 16°, against the piston 16, and so hold all the rings
and distance pieces together and against the seat 17ª on the valve rod. The
collar 16, when used, may serve as a junk ring for the piston 16. 16 are lock
nuts of any suitable kind, screwed onto the valve rod for preventing the sleeve 16b
from working loose. The pair of low pressure valves 25 and 25 may, as shown,
be similarly fixed on the valve rod 17 so as to be supported, or partly supported,
by steam pressure. In like manner the controlling valve 21 may, if desired, be
replaced by a pair of pistons like 25 and 25" and be fixed upon the valve rod 22
by a sleeve tightened up from the outside. Or the said controlling valve may,
as shown, be made as a slide valve and be operated by a surrounding ring or
bridle 22 on the rod 22, the upper portion of which rod, working through the
top stuffing box 22b, is made of larger diameter than the portion working through
the lower stuffing box 22°, so that there shall be an excess of steam pressure tend-
ing to lift the valve rod and valve.
The main valve rod 17, which is common to the high and low pressure valves, is
made in two parts connected together by a right and left handed screw threaded
nut 17, provided with check nuts, so as to allow of adjustment of the high and low
pressure valves, and of the rod being easily put in position and removed.
At points
below the valve chest 23, the valve rod 17 is provided with collars or tappets 29, 29"
arranged in the path of a part 11ª of the cross head 11 through which and a
lower fixed guide 30, the said valve rod extends. The controlling valve rod 22 is
also provided with collars or tappets 31, 31ª arranged in the path of another
part 11 of the cross head 11 through which and a lower fixed guide 32 the said
valve rod 22 extends. The collars 31, 31ª are placed nearer together than the

page_text: collars 29, 29ª in order that the part 11b of the crosshead 11 shall, as the pistons 7
and 8 approach each end of their strokes, act upon one or other of them and move
the controlling valve 21 in such a way as to enable the high and low pressure valves
to be actuated by the pressure of steam admitted through one or other of the
5 passages 19 or 19", but should the said valves for any reason fail to be thus operated,
they will be positively actuated in the required direction by the action of the
crosshead on one or other of the collars 29, 29".
material, such as india rubber or leather, to lessen shock and avoid noise when
33 are washers of suitable
the crosshead acts upon the said collars. As will be seen the various steam passages
0 are so arranged that water of condensation will drain away and escape through the
exhaust pipe 28, thereby obviating any trouble arising therefrom.
The pump is double acting, the passage of water to and from the ends of its
barrel 5 through pasages 34 and 34" being controlled in the ordinary way by suction
and delivery valves which may be of the usual or any suitable construction
5 and are arranged to work in the valve chest 35 in a manner well understood.
As will be seen the, construction and arrangement of the several parts is such
that when the high and low pressure pistons 7 and 8 approach the lower end
of their strokes, the cross head 11 by acting upon the collar or tappet 31ª will move
down the valve rod 22 and valve 21 so as to put the upper and lower ends of the
valve chest 12 respectively in communication with the auxiliary valve chest 20
and exhaust port 20b and allow steam to act upon the upper end of the piston 16 in
the main valve chest 12 and force the high and low pressure valves into the
positions shown in Fig. 1. High pressure steam will then flow from the central
space between the high pressure valves 14, 14" to the lower end of the high pressure
cylinder 1, and steam that has done duty in that cylinder will flow therefrom
through the upper annular passage 18 between the valve 14 and piston 16, to the
exhaust pipe 27 and passage 26 and thence through the space between the low
pressure valves 25, 25" and the lower steam passage 24" to the lower end of the low
pressure cylinder 2, both pistons then making their upstroke. On the pistons
approaching the end of their upstoke, the crosshead 11 by acting upon the collar
or tappet 31 will raise the controlling valve 21 and adinit steam to the lower end of
the main valve chest whereby the high and low pressure valves will be raised so
as to admit steam to the upper ends of the high and low pressure cylinders 1
and 2 and exhaust steam from the lower ends thereof, the pistons then making
their downstroke.
In order that high pressure steam may be automatically admitted to the low
pressure cylinder 2 so as to facilitate the starting of the pump at full load, and
such steam after starting, be automatically cut off, there may be provided in the
connection between the high and low pressure cylinders 1 and 2, an automatic
starting valve as shown at 36 in Fig. 2.
Figs. 6 and 7 show respectively in vertical section and side elevation, one con-
truction of starting valve suitable for the purpose mentioned. Figs. 8 and 9
re sections on the line y y and zz respectively of Figs. 6 and 7. In this arrange-
ent, the valve case 36 is provided with inlet and outlet branches 37 and 38 that are
onnected respectively to the exhaust pipe 27 and to the steam inlet of the low
ressure cylinder 2, and also with an inlet branch 39 and passages 40 for admit-
ng high pressure steam from the main steam pipe to the interior of the valve case
elow an automatic differentially acting steam valve 41. This valve 41, which is of
isc form, is provided on its lower side with a stem 42 arranged to work in the
ranch 39, and on its upper side with a stem 43 that is of larger cross sectional
ea than the stem 42 and works in a cylinder 44 the top of which is in com-
unication through a passage 45 with the exhaust steam inlet branch 37. The
rangement is such that when high pressure steam is admitted to the high pres-
re cylinder 1 at starting, high pressure steam will also enter the branch 39 and
it the steam valve 41 into the raised position shown in Fig. 6 so as to close the
mmunication between the high and low pressure cylinders, the steam so admitted
ssing into the low pressure cylinder so that both cylinders then act as high

page_text: pressure cylinders. The quantity of high pressure steam thus supplied to the low
pressure cylinder is so regulated that on entering the valve case its pressure will
be reduced to such an extent that the total pressure on the underside of the steam
valve 41 will be less than the total pressure of the exhaust steam from the high
pressure cylinder acting upon the upper side of the said valve and the stem 43,
so that upon steam exhausting from the high pressure cylinder it will force the
steam valve 41 into its lower position, cutting off the supply of high pressure
steam to the valve chest 36, and opening the communication between the exhaust
pipe 27 and the steam inlet 26 of the low pressure cylinder and enabling the two
cylinders to work as compound cylinders in the ordinary way.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is-
1. In a steam pump, fixing the steam distributing valves, or each set of such
valves, with or without pistons, upon their operating rod by means of a sleeve that
surrounds the valve rod at one end of the set of valves, extends through a stuffing
box to the exterior of the valve chest, and is fixed upon the said red outside the
said valve chest, the external diameter of the sleeve being greater than the diameter
of that portion of the valve rod working through the other end of the valve chest,
substantially as described with reference to the drawings annexed for the purposes
specified.
2. A compound steam pump having high and low pressure steam distributing
valves and a controlling valve, constructed, arranged and operating substantially
as hereinbefore described with reference to the drawings annexed.
3. The improved compound steam pump herein before described with reference
to and shown in the drawings annexed, whether with or without the automatic
starting valve.