Improvements in or relating to Steam Traps.
Year: 1898

page_text: Date of Application, 25th Aug., 1898
Complete Specification Left, 26th June, 1899-Accepted, 25th Aug., 1899
Improvements in or relating to Steam Traps.
I, ROBERT GRUNDY BROOKE, of Upton Grange, Macclesfield, in the County of
Chester, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention has for object to enable steam traps of the expansion type
to deal more efficiently than heretofore with the water of condensation from
high pressure steam. For this purpose according thereto the water of con-
densation is collected inside the trap in order to procure a greater difference in
temperature than would be the case if the water of condensation were allowed to
blow through and expand into the steam inside the trap as has been the case
hitherto; and also to enable the operator to see by means of gauge glasses whether
the trap contains water or steam, as the condensation water at high pressures
becomes steam immediately on escaping into the outer air, in consequence of
which it has been usually impossible to ascertain whether water or steam was
being discharged. For this reason traps heretofore in use have frequently been
regarded as defective when the condensation water, being over 212° Fahrenheit,
discharged from the trap as steam.
According to one arrangement there is employed an expansion trap or apparatus
of the kind described in the Specification of my former Letters Patent No. 16152
of 1895 and which comprises a casing having inlet and outlet openings, the
inlet being controlled by a conical valve fast on one end of a spindle arranged
within the casing. This spindle is secured to one end of a closed curved tube
that is charged with a volatile liquid such as petroleum spirit and the other end
of which is pressed against an adjustable stop by a spring interposed between
the said end and a lug fixed in the casing.
To enable the water to collect inside the casing there is placed a weighted valve
or equivalent device in the outlet end, this valve being suitably weighted as
may be required. In some cases it may be desired to reduce the pressure before
it enters the trap, in which case a reducing valve is placed in the inlet pipe.
The trap is also provided with gauge glasses whereby a person can see if the
trap is discharging water or steam although owing to its temperature it may
issue into the air as steam. In order to prevent the closed curved tube from
taking a permanent set by being subjected to high temperatures, it is suitably
strengthened as for example by means of corrugations or ribs at or about the
middle of the tube and extending towards the ends. The arrangement is such
that water gradually enters and rises in the trap up to a certain height but
without raising the pressure in the trap sufficiently to open the weighted valve,
whereupon this water having gradually become cooled by radiation through
the casing and the tube being protected from the incoming hot water or steam
for a certain distance by the cooler water the tube is free to contract sufficiently
to enable a considerable inrush of steam and water to take place whereupon the
pressure inside the trap rises sufficiently to discharge the whole or part of its
contents through the weighted outlet valve. The tube being thereby uncovered
and exposed to the temperature of the steam, again expands and closes the valve,
whereupon water only again commences to trickle in past the valve in the ordinary
TD 077

page_text: manner until it has again reached a certain height in the trap whereupon the
same operation is repeated.
By these means the curved tube is given a greater action than if it were
continually surrounded by steam, as the temperature of the water in the casing
can continue to fall whereas the steam never gets below a certain temperature.
The range of temperature acting on the tube is thereby increased and the action
of the latter rendered more reliable and efficient. The casing or body of the trap
can be made of any desired shape or size so as to form a reservoir, or it can be
connected to a reservoir whereby large quantities of water can be dealt with.
Dated this 25th day of August 1898.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.
1, ROBERT GRUNDY BROOKE, of Upton Grange, Macclesfield, in the County of
Chester, Engineer, 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:―
This invention has for object to enable steam traps of the expansion type
to deal more efficiently than heretofore with the water of condensation from
high pressure steam. For this purpose according thereto the water of con-
densation is collected inside the trap in order to procure a greater difference in
temperature than would be the case if the water of condensation were allowed
to blow through and expand into steam inside the trap as has been the case
hitherto, and also to enable the operator to see by means of gauge glasses
whether the trap contains water or steam, as the condensation water at high
pressures becomes reconverted into steam immediately on escaping into the outer
air, in consequence of which it has been usually impossible to ascertain whether
water or steam is being discharged from the trap. For this reason traps, as
heretofore in use, have frequently been regarded as defective when the con-
densation water, being over 212° Fahrenheit, is discharged from the trap as steam.
Fig. 1 of the accompanying illustrative drawings shows partly in side eleva
tion with the cover removed and partly in section, an expansion trap or apparatus
of the kind described in the Specification of my former Patent No. 16152 of
1895 but modified according to my present invention. Fig. 2 is a section on
the line AB of Fig. 1 with the internal parts of the trap omitted.
The trap in this example comprises a casing 1 having an inlet 2 for hot
water, and an outlet therefor at 3. The inlet 2 is controlled by a conical valve 4
fast on one end of a spindle 5 that is secured to one end of a closed curved ex-
pansion tube 6 which is charged with a highly volatile liquid, such as petroleum
spirit, and the other end of which is pressed against an adjustable stop 7 by
a spiral spring 8 interposed between the said end and a lug or stop 9 fixed in
the casing 1 as in the trap described in my said former specification.
To enable water to collect inside the casing 1 the outlet 3 is controlled by a
loaded valve 10 which can be regulated to blow off at any desired predetermined
pressure by the aid of a spring 10", but other arrangements can, if desired, be
used to load the valve to the desired extent. In the arrangement now being
described the valve 10 is arranged at one side of and at a point level or approxi-
mately so, with the inlet 2 and is connected to the outlet 3 by an external pipe 3º.

page_text: The casing of the trap is provided with a gauge glass 11 (Fig. 2), so that a
person can readily see whether the trap is discharging steam or water, even
when the latter, owing to its being at a high temperature and pressure, is re-
converted into steam on issuing into the external atmosphere.
The gauge
glass may be a tube of ordinary kind, but conveniently it may consist, as in
the arrangement shown, of a strip of glass held opposite an opening in the
cover 1b of the trap by a frame 11" that is drawn up by set screws 11.
Within the casing 1, and near the upper end thereof, is a wall or partition 12,
which gradually slopes from the inlet 2 to a point about half way down one side
of the casing so that the interior of the casing is of smaller cross sectional area
at the top than it is at the centre. Opening into the casing 1 above the wall
or partition 12 near the inlet 2 and communicating with the steam and water
space of the trap through an orifice 12 in the said wall or partition 12, is a
pipe 13 which communicates with the pipe 3 at or near its highest point. 14
is a pressure gauge connected with the interior of the casing 1 at 14" and by
the aid of which the valve 10 can be set or regulated to blow off at any desired
pressure.
The arrangement is such that as water gradually enters the trap by the inlet 2
it rises in the trap and pipe 3" to a certain height, but without raising the
pressure in the trap sufficiently to open the loaded valve 10, the water being
prevented from rising to a greater height in the pipe 3" than in the trap by
reason of the two being in communication through the pipe 13. As the water
in the trap becomes gradually cooled by radiation through the casing and as
the tube 6 is protected from the incoming hot water or steam for a certain
portion of its length by the cooler water, the tube is free to contract sufficiently
to enable a considerable inrush of steam and water to take place through the
inlet 2, whereupon the pressure inside the trap will rise sufficiently to overcome
the resistance of the spring 10% of the valve 10 and permit of the whole or
part of the contents of the trap being thereupon discharged through the said
valve. The tube 6 being thereby uncovered and exposed to the steam, again
expands and nearly closes the valve 4, whereupon water again commences to trickle
in past the valve 4 in the ordinary manner until it has again reached a certain
height in the trap whereupon steam will again enter the trap and force out
the water therein as before.
Owing to the position of the wall or partition 12 in the interior of the casing,
the water chamber is of such a shape that when the steam enters it to force out
the water, the surface of the water with which it conies in contact is of com-
paratively small area instead of being the full area of the trap whereby boiling
up of the water, which would otherwise occur, is prevented.
In some cases a cock or self acting valve may be fixed in the pipe 13 to
prevent water blowing back from the pipe 3" into the interior of the trap.
In the modified arrangement shewn in Fig. 3, which is a view similar to Fig. 2
of part of the trap, the valve 10 is fixed directly onto the outlet 3 instead of
being fixed to the end of a pipe 3. With this arrangement the valve 10 is
kept permanently in contact with hot water instead of with steam as in the
arrangement shewn in Fig. 2, but the latter arrangement (Fig. 2) is preferred.
Fig. 4 is a central vertical section and Fig. 5 a cross section on the line C-D
of Fig. 4, showing a modified construction of steam trap acrording to this
invention.
In this arrangement the casing 1 of the trap is made for a portion of its length
of gradually decreasing diameter upward, the steam being thereby prevented
from causing a boiling up of the water within the trap when it is admitted for
the purpose of forcing out the contents of the trap.
The tube is arranged horizontally instead of vertically as in Fig. 1, and
is hinged at one end to a plate 15 which is secured to but held at a short distance
above the bottom of the trap by lugs 19. The other end of the tube 6 is con-
nected to the spindle 5 carrying the valve 4 by a connecting rod 5" and a bell

page_text: crank lever 5b on a shaft 5°. The upper surface of the plate 15 is provided with
ribs 15 so as to keep the tube clear of the said plate as it moves to and fro
owing to expansion or contraction.
The outlet passage 3 in this case is shown cast in one piece with the casing 1
and extends from a point below the plate 15 to a point near the upper end of
the casing to the outlet 3 of which the loaded valve 10 is applied. 13 is a
hole by which the top of the passage 3ª is placed in communication with the
interior of the trap. This hole may be regulated by a conical valve carried by
a spindle extending through a stuffing box on the casing 1.
In this arrangement it will be seen that the tube 6 is throughout its whole
length either entirely immersed in water or entirely subject to the action of
steam, the operation being the same as that of the trap shown in Figs. 1 and 2.
Fig. 6 is a central vertical section and Fig. 7 a plan on the line G H of Fig. 6,
showing a further modified construction of steam trap according to this inven-
tion. In this case the inlet valve spindle 5 is made an easy fit in a bush 16
arranged between the inlet 2 and the interior of the trap, and a pipe or passage 17
is provided between the space or chamber 18 and the upper part of the interior
of the trap. The arrangement is such that water can flow into the bottom of
the trap through the bush 16 and around the spindle 5 but upon steam entering
the chamber 18, instead of it flowing through the restricted passage around the
spindle 5 and blowing up through the water in the trap it will take the easier
path through the pipe or passage 17 and enter the trap at the top. The
expansion tube 6 is arranged horizontally as in the arrangement shown in
Figs. 4 and 5 but acts directly on the valve spindle 5 as in Figs. 1 and 2, the
water outlet passage 3 to which the loaded valve 10 is applied being cast in
the wall of the upper and lower portions of the casing 1 and provided with a
hole 13 which may be controlled by a valve as before. This modified con-
struction of trap operates in the same manner as that shown in Figs. 1 and 2.
By the means hereinbefore described the tube 6 is given a greater action
than if it were continually surrounded by: steam, as the temperature of the water
in the casing can continue to fall whereas the steam can never get below a
certain temperature. The range of temperature acting on the tube is thereby
increased and the action of the latter rendered more reliable and efficient. The
casing or body of the trap may be made of any desired shape, or size, so as to
form a reservoir, or it may be connected to a reservoir, whereby large quantities
of water can be dealt with.
In order to prevent the tube 6 from taking a permanent set by being subjected
to high temperatures, and consequently high pressures, it is or may be suitably
strengthened as for example by means of corrugations or ribs formed at or about
the middle of the tube and extending towards the ends. Fig. 8 is a side cleva-
tion and Fig. 9 a cross section on the line EF of Fig. 8, showing an expansion
tube 6 thus strengthened by corrugations at 6", these corrugations strengthening
the tube at its weakest part and enabling it to be made of thinner and more
elastic material than would otherwise be possible. In some cases it may be
desirable to reduce the pressure before it enters the trap in which case a reducing
valve may be placed in the pipe connected to the inlet 2.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
1. In a steam trap having an expansion tube arranged therein to control the
inlet of water of condensation and steam, controlling the water outlet of the
trap by a weighted or loaded valve arranged to blow off at a predetermined
pressure so that water of condensation can collect in the trap around the ex-
pansion tube before being blown out by steam, substantially as herein described
for the purpose specified.
2. A steam trap comprising a casing provided with an inlet for water of

page_text: condensation and steam, an outlet for water of condensation, an expansion tube
arranged within the casing and so as to control the said inlet, a loaded or weighted
valve controlling the said outlet, and a water gauge whereby the height of water
in the trap can be readily seen from the exterior thereof, substantially as
described.
3. For a steam trap of the kind herein referred to, a closed curved expansion
tube formed with corrugations or ribs to increase its strength, substantially as
described.
4. Expansion steam traps constructed arranged and operating substantially
as hereinbefore described with reference to and shown in Figs. 1 and 2; in
Fig. 3; in Figs. 4 and 5, and in Figs. 6 and 7 of the accompanying drawings.
Dated this 26th day of June 1800
For the Applicant,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.