Improvements in Steam-traps.
Year: 1893

page_text: Date of Application, 8th Sept., 1893-Accepted, 2nd Dec., 1893
[Communicated from abroad by MATTHEW GILMORE, of 89, Henry Street,
Brooklyn, New York, United States of America, Engineer.]
Improvements in Steam-traps.
1, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake and Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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 its object to provide a steam trap of simple and durable
construction, free from the features which render many of the familiar types of
steam traps objectionable, such features, for example, being floats or buckets and
expansion devices, my improved trap being destitute of any device such as a float
or bucket or any expansion device, and being governed by variations of pressure
on a flexible diaphragm which controls a valve.
The invention consists in the several improvements which I will now proceed to
describe and claim.
Of the accompanying drawings, forming a part of this Specification:
Figure 1 represents a vertical section of a steam trap embodying my invention.
Figure 2 represents a vertical section showing certain differences in the manner
of operating the trap, the essential features being the same as in Figure 1.
The same letters of reference indicate the same parts in both the figures.
In the drawings:
A represents a water chamber, formed in a supporting base or casing A. One
side of said chamber is formed by a flexible diaphragm Ď, which may be of rubber
or any other suitable material, the diaphragm having preferably a considerable
area.
At the opposite side of the diaphragm D is a chamber B, the two chambers
being entirely separated by the diaphragm, which constitutes the bottom of one
chamber and the top of the other. The chamber B is provided with an outlet tube
or passage B', which is preferably, although not necessarily, arranged as shown in
the drawings; that is to say, it is a tube, attached at its upper end to the wall of
the chamber B, and projecting downwardly therefrom, its lower end having an
opening B. The upper end of the outlet or tube B' communicates with a passage K
in the casing which passage communicates with a waste pipe K'. E represents a
valve, which is adapted to rest upon the diaphragm D, and also to close the outlet
opening B. Said valve is here shown as attached to a yoke G, which is formed on
a tubular frame or slide G¹, fitted to move upon the outlet tube B'. The slide G¹
is provided at its lower end with a flange G, on which bears one end of a helical
spring S, the other end of which bears on a fixed seat on the casing, or elsewhere.
The spring S normally presses the valve E away from its seat, so that, when the
pressure in the chamber A is reduced, as hereinafter described, the valve is
normally opened, and permits the escape of water from the chamber B to the waste
pipe K, the diaphragm D supporting the valve E and holding it against its seat
under certain conditions, as presently described.
P represents a passage or port, which admits water into the chamber B. Said
passage communicates with a chamber C, formed in the casing A', said chamber
also communicating with a vertical stand pipe H, which rises to a considerable
height above the level of the diaphragm D, and is open at its upper end, said upper
end being located in a condensing chamber or reservoir J. I represents a vertical
pipe, which communicates at its upper end with the reservoir J, and at its lower
end with the chamber A below the diaphragm. For convenience, I have shown

page_text: the pipe I as surrounding the stand pipe H and separated therefrom by an annular
space, but said pipes may be otherwise arranged, if preferred. The communication
between the lower end of the pipe I and the chamber A is here shown as effected
by means of a port T, formed in the casing, and a pipe R, connecting said port
with the chamber A, said pipe being chosen for the sake of clearness of illus-
tration, although in practice I prefer to connect the port T with the chamber A.
by a passage or port formed within the body of the casing.
W W represent a series of heating pipes, and W°a head or connection com-
municating with said pipes. In the construction shown in Figure 1, I show the
head W connected by a pipe O with the chamber C in the casing, this being a
convenient arrangement where the vertical space is limited. In Figure 2, I show
an arrangement which may be adopted where there is sufficient vertical space for
the location of the trap below the steam pipes, the connecting pipe O being, in the
construction shown in Figure 1, connected with the upper portion of the condensa-
tion chamber or reservoir J.
Operation: For the purpose of describing the operation of the steam trap, when
connected with the steam pipes in the manner shown in Figure 1, let it be supposed
that the area of the diaphragn D is equal to twenty-eight (28) square inches, that
the spring S exerts a downward pressure of fourteen (14) pounds on the diaphragm,
that the vertical distance from the diaphragm to top of stand pipe H is equal to
twenty-seven (27) inches, and that the shell A and pipes R and I are filled with
water up to the level of top of pipe H. The column of water in pipe 1 presses on
the under side of the diaphragm D with a force equal to one (1) pound per square
inch or twenty eight (28) pounds on the whole area of the diaphragm : consequently
the diaphragm is forced upwards against the counter-pressure of the spring S, and
holds the valve E to its seat with a net force of fourteen (14) pounds. The
chamber J is made of considerable capacity in order that the movement of the
diaphragm will not materially effect the height of the water column in pipe I.
Steam being admitted to the heating pipes W, the water of condensation and
the steam flow into and fill shell B. The steam, meanwhile, has free access through
pipe H to the interior of chamber J, and presses with the same force on the surface
of the water contained in it as it does on the water in shell B, but the pressure on
the under side of the diaphragm (because of the head of water in pipe I) in the
same proportion that it was before steam was admitted. The water of condensation
accumulates in pipe O until it reaches the level of the bottom of pipe H, thereby
shutting the steam off from pipe H and chamber J,-in other words, forming a
water seal. The steam which remained in pipe H and chamber J immediately
begins to condense and fall in pressure, and as condensation goes on, the water rises
in pipe H, because of the decreasing pressure on the upper portion of said pipe.
The upward pressure exerted on the under side of the diaphragm therefore com-
mences to decrease when the lower end of the pipe H is sealed, said pressure
gradually decreasing until it becomes less than the combined downward pressure of
the steam and the valve spring and permits the opening of the valve. When the
water has risen to a point midway of the length of the pipe, or thirteen and one
half (13) inches, measuring upward from the level of the diaphragm, the steam
pressure (as indicated in my experiments by a steam gauge on top of chamber J and
a gauge glass one pipe H) has fallen one half (4) pound per square inch below the
upward pressure on the diaphragm D. This is evident, as it requires a pressure of
one-half () pound per square inch to support a column of water thirteen and one-
half (13) inches in height. Assuming that there is a constant steam pressure of
ten (10) pounds on the heating pipes, the pressure now on the under side of the
diaphragm is ten and one-half (10) pounds per square inch (nine and one-half
pounds steam pressure and one pound water pressure), and the pressure on the
upper side is ten and one-half (10) pounds per square inch (ten pounds steam
pressure and one-half pound spring pressure). The area upon which pressure acts
is greater on the lower surface of the diaphragm than on the upper surface, to the
amount of the area of the opening covered by the valve E, when said valve E is

page_text: closed, therefore the valve remains closed until the pressure on the greater area of
lower surface of the diaphragm becomes less than the pressure on the smaller area
of the upper surface, when the valve opens and allows the water to escape through
port K. When the water in pipe O falls below the level of bottom of pipe H,
steam enters chamber C, and, as it is of a greater pressure than the steam in the
upper part of chamber J, it flows up through the water in pipe H and equalizes
the pressure in chambers J and C, the water in pipe H having meanwhile fallen into
chamber C and space above diaphragm. The pressure now in chamber J, acting
on the surface of the contained water and on the under side of the diaphragm,
raises the diaphragm and closes the valve E. This action is repeated at such
short intervals that the flow of water is practically constant, as I have demonstrated
by experiment.
When the apparatus is arranged as shown in Figure 2, the pipe O being
connected with the upper portion of the reservoir J, the steam and water of
condensation enter the said reservoir directly, and pass downwardly through the
stand pipe H, chamber C and port P to the chamber B, the pipe I and reservoir J
being full of water to the level of the top of stand pipe H, as before. As the
water of condensation accumulates, it fills the chamber B and rises in the stand
pipe H. Before the water attains any considerable height in the pipe H, the steam
pressure is practically the same on both sides of the diaphragm, so that the latter
is subjected to an upward pressure of eleven (11) pounds per square inch (ten
pounds steam and one pound water) and a downward pressure of ten and one-half
(10) pounds (ten pounds steam and one-half pound spring), so that the valve
remains closed. As the water rises in the pipe H, the pressure due to the height
of the column of water in said pipe is added to the steam pressure on the upper
surface of the diaphragm, said water pressure reaching one-half () pound per square
inch when the pipe H is half full of water, or when the column of water in said pipe
is thirteen and one-half (13) inches above the level of the diaphragm; so that the
upward and downward pressures on the diaphragm are balanced. Any further
increase in the height of water in the stand pipe H therefore causes the depression
of the diaphragm and the opening of the valve. The ensuing escape of water then
decreases the downward pressure on the diaphragm until the valve is closed, and
thus the operation continues, the valve alternately opening and closing; but, as in
the operation of the apparatus as first described, the action is repeated at such
short intervals that the flow of water is practically continuous.
I have shown at L a blow-off pipe connected with the upper portion of the
passage K, said. pipe having a blow-off cock N. Z represents a glass gauge tube,
connected with the chamber B, and with a tube Z' communicating with the upper
portion of the reservoir .J.
My invention is not limited to the particular arrangement and construction of
parts here shown, and the same may be variously modified without departing from
the spirit of the invention.
Some of the advantages of this trap are as follows:
First. Its action is not affected by short quick vibrations, such as occur on steam
cars, where float or bucket traps will not work on account of such vibrations.
Second. It can be connected close to the heating pipes, and will take away the
water of condensation as fast as formed, regardless of the temperature of the water,
or variation of pressure in heating pipes, a result that cannot be produced by
expansion traps.
Third. It is considerably smaller and lighter than float and bucket traps of the
same capacity.
Fourth. Its capacity can be increased indefinitely by enlarging valve E and
increasing height of pipes H and I. This increase in capacity can be obtained at a
less cost than in other traps.
It is obvious that any other suitable means for maintaining a constant pressure
on the diaphragm may be substituted for the spring S, such, for example, as a
weight.

page_text: I do not limit myself to the direct connection of the diaphragm with the valve or
device which is operated by the fluctuations thereof, as said valve may be located
outside of the casing and operated through suitable connections with the diaphragm
passing through the casing.
A distinguishing characteristic of my invention is the combination of a diaphragm
or partition constantly pressed in. one direction, and connections between the
opposite sides of said diaphragm or partition and a source of steam supply, one of
said connections including a stand pipe adapted to contain a column of water which,
when the steam pressure is equal on both sides of the diaphragm, overcomes the
said constant pressure. I believe myself to be the first to organize an apparatus of
this kind having the features just mentioned, the arrangement being such that an
accumulation of water of condensation causes an increase of pressure on the
constantly pressed side of the diaphragm, while a falling off of the quantity of
water of condensation causes a decrease of pressure on the said constantly pressed
side.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1st. The combination of two chambers separated by a partition or diaphragm
adapted to be moved by variations of pressure; a pressure device such as a spring,
arranged to exert a constant pressure on one side of said partition; connections
between said chambers and a source of steam supply, whereby steam and water
of condensation from said source may be admitted to both sides of the diaphragm,
said connections including a condensing chamber or reservoir, located above the
level of the partition, and conduits connecting said reservoir and the two chambers,
said reservoir and one of said conduits being adapted to contain a column of water,
which, with the steam pressure equal in the two chambers, overcomes the constant
pressure on the diaphragm, the arrangement being such that an accumulation of water
of condensation in the conduit connecting the reservoir with the constantly pressed
side of the partition causes a variation of pressure on one side of the partition;
and a device, such as a valve, operated by fluctuations of the partition; as
set forth.
2nd. The combination of two chambers, separated by a movable partition or
diaphragm; a pressure device, such as a spring, arranged to exert a constant
pressure on one side of said partition; a condensing chamber or reservoir, elevated
above said partition; a stand pipe, communicating at its upper end with said
reservoir, and at its lower end with the constantly pressed side of the partition ;
another stand pipe, communicating at its lower end with the opposite side of
the partition, and at its upper end with the reservoir; and an inlet for steam
and water of condensation, the arrangement being such that, before the accumu-
lation of water of condensation in the apparatus, the steam pressure is equal on
both sides of the partition, and the water in one of said stand pipes, aided by the
steam pressure, overcomes the constant pressure on the partition, while an
accumulation of water causes a variation of pressure on one side of the partition;
as set forth.
3rd. The combination of two chambers, separated by a movable partition or
diaphragm a pressure device, such as a spring, arranged to exert a constant
pressure on one side of said partition; a condensing chamber or reservoir, elevated
above said partition; a stand pipe, communicating at its upper end with said
reservoir and at its lower end with the constantly pressed side of the partition;
another stand pipe, communicating at its lower end with the opposite side of the
partition, and at its upper end with the reservoir; a chamber at the base of one of
said stand pipes, said chamber communicating with the chamber at the constantly
pressed side of the partition; and an inlet for steam and water of condensation,
communicating with said chamber, the arrangements being such that, when said
cbamber is open to receive steam, there is a uniform steam pressure on both

page_text: sides of the partition, and, when the water of condensation accumulates in said
chamber, it shuts off the direct steam pressure from one side of the diaphragm
and reduces the pressure thereat, as set forth.
Dated this 8th day of September 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.