AN IMPROVED STEAM TRAP
Year: 1885

page_text: I, OLIVER IMRAY of N° 28 Southampton Buildings, Chancery Lane in the
County of Middlesex, Fellow of the Institute of Patent Agents do hereby declare
the nature of my invention for "AN IMPROVED STEAM TRAP" to be as follows:-
This invention relates to a construction of steam trap or apparatus which
permits outflow of water of condensation from a vessel or pipe charged with steam,
without allowing steam to escape. Instead of effecting this by the intermittent
action of moveable parts as in many steam traps, it is, according to this invention,
effected by compelling such steam as might tend to escape to follow tortuous or zig
zag passages or channels undergoing great and sudden variations of sectional area.
One form of trap acting on this principle is a closed vessel having several ledges
projecting inwards from its sides to form seats for several tiers of plates placed on
them, each of those plates being a little smaller than the part of the vessel in which
it is placed. In the ledges under the plates are small grooves. The water of
condensation can pass between the edges of the successive plates and the sides of
the vessel and along the grooves. Should steam also tend to pass, it will, after
passing one of the plates expand in the space under it, then pass another plate and
so on, losing its pressure by expansion and condensation. At the bottom of the
vessel there is an outflow nozzle which, once adjusted to suitable area, allows
a continuous outflow of water of condensation without steam. The plates may be
with advantage made of metal more expansible by heat than the material of which
the vessel is made. Should steam pass a plate instead of water, the plate will
become so far expanded as to throttle at its edges the passage for steam. Or,
according to another modification, the plates may be made of material lighter than
water, so that if any compartment of the vessel should happen to become filled
with water more rapidly than it can escape, the plate which forms the bottom of
this compartment becomes floated up, giving free passage. Instead of plates being
וע...

page_text: thus employed to separate the compartments, balls of caoutchouc or other elastic
material may be used, and the vessel may be of conical form with annular inwardly
projecting ledges, each ledge, whilst it forms the seating for one of the balls,
forming a stop to prevent the next lower ball from being displaced by floatation
beyond a certain distance. Such a vessel may be of glass so that the condition of
the interior can at all times be seen.
Dated this 8th dow of Cantomban 1007
ABEL & IMRAY,
Agents for the Applicant.
I, OLIVER IMRAY, of No 28, Southampton Buildings Chancery Lane 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 relates to a construction of steam trap or apparatus which
permits outflow of water of condensation from a vessel or pipe charged with steam,
without allowing steam to escape. Instead of effecting this by the intermittent
action of moveable parts as in many steam straps, it is, according to this invention,
effected by compelling such steam as might tend to escape to follow tortuous or zig-
zag passages or channels undergoing great and sudden variations of sectional area.
One form of trap acting on this principle is a closed vessel having several ledges
projecting inwards from its sides to form seats for several tiers of plates placed on
them, each of those plates being a little smaller than the part of the vessel in which
it is placed.
In the ledges under the plates are small grooves. The water of condensation can
pass between the edges of the successive plates and the sides of the vessel and along
the grooves. Should steam also tend to pass, it will, after passing one of the plates,
expand in the space under it, then pass another plate and so on, losing its pressure
by expansion and condensation. At the bottom of the vessel there is an outflow
nozzle which, once adjusted to suitable area, allows a continuous outflow of water
of condensation without steam. The plates may be with advantage made of metal
more expansible by heat than the material of which the vessel is made. Should
steam pass a plate instead of water, the plate will become so far expanded as to
throttle at its edges the passage for steam. Or, according to another modification,
the plates may be made of material lighter than water, so that if any compartment

page_text: of the vessel should happen to become filled with water more rapidly than it can
escape, the plate which forms the bottom of this compartment becomes floated up,
giving free passage. Instead of plates being thus employed to separate the compart-
ments, balls of caoutchouc or other elastic material may be used, and the vessel may
be of conical form with annular inwardly projecting edges, each ledge, whilst it
forms the seating for one of the balls, forming a stop to prevent the next lower ball
from being displaced by floatation beyond a certain distance. Such a vessel may
be of glass so that the condition of the interior can at all times be seen.
Fig. 1 of the drawings shews a cross section of one arrangement of the above
described automatic steam trap with continuous action and Figs. 2 and 3 shew
enlarged details of the separating partitions with their supports.
As above stated, the steam, on entering the apparatus, becomes at once condensed
by a series of consecutive expansions and an equilibrium between the quantity of
water that condenses in the apparatus and the discharge of the condensed water
through the exit orifice of the apparatus is established. The apparatus consists of
a conical or tapering vessel M, of cast iron or other metal, closed at the bottom and
provided with annular ledges etc. which serve as supports to the metal
dises d' d' d. A cover N secured steam tight to the top of the vessel M carries
the admission pipe A. The tortuous passages are formed by small cylindrical
depressions or grooves a formed in the ledges r¹³ ³ Figs. 2 and 3. Instead
of being formed on the ledges 71, the grooves a might be formed on the under-
sides of the discs, as shewn at Figs. 4 and 5 which shew respectively a vertical
section and a plan of a disc, in this case the ledges would have no depressions. The
orifice O is a capillary opening at the end of the conical discharge pipe T, by
preference of copper. The size of this opening can be regulated by cutting the
Dozzle off to any required extent, thus regulating the discharge of water from the
apparatus, so that no steam shall ever escape. If the opening O was too large in
the first instance, it can be made smaller by pinching it together. This regulation
once established, it has been found by experiment that whatever be the pressure of
steam in the apparatus, only water will issue through the nozzle, the pressure only
serving to vary the speed of discharge.
It will be seen from this description that the whole of the steam entering
the apparatus will become condensed in the same, yielding up to the water of
condensation its latent heat so that only water will be discharged from the
apparatus.
The action of the above described apparatus is regular for a given mean pressure
of steam, but, owing to the uniform size of its orifices, it is not readily applicable
to sudden variations in the discharge of condensed water. It is therefore desirable
that the apparatus should of itself be capable of increasing or diminishing the
discharge orifices according to the variation of the quantity of water produced in a
unit of time. This result is obtained by forming the discs that produce the
successive reductions of pressure, either of a material that expands more by heat
than the material of which the casing is made, or of a material that is less dense
than water. When making the discs of a material that expands more by heat than
the casing, there is employed by preference for this purpose, an alloy of copper,
lead, zinc and tin; the composition which has given the best results being as
follows, copper 55 parts, lead 5 parts, zinc 38.5 parts tin 1.5 parts, total 100 parts.
It will be readily understood that the discs being made of a material that
expands more by heat than the casing of the apparatus, they will, by expand-
ing, when brought into contact with the hotter water that immediately precedes
the steam, when the greater part of the water of condensation has been dis-
charged, choke the discharge passages to a greater extent and thus reduce the

page_text: outflow. Thus it is the steam itself which reduces the passage of water by
successively expanding each disc which is opposed to its flow. When the discs are
less dense than water, it will result that when the level of the water rises to A¹ B¹,
Fig. 6, all the discs dd below that level will float as shewn, while those that are
above that level will continue to act in the ordinary manner. Thus the discharge
will be increased by diminishing the number of obstacles to the passage of the
water until, by the sinking of the water level, the lower discs again assume their
original position on the ledges. In the case where the partitions and the casing
are made of different densities, these partitions may be advantageously formed as
floating spheres instead of as discs, as the latter might present the inconvenience
of not falling back into their proper position. These spheres would be made
sufficiently elastic to enable them to be forced through the slightly smaller opening
above, into the chamber, on the opening below of which they take a seating, so
that when, on the rising. of the water level, they float upwards they will not be
enabled to pass through the upper opening. This construction of the apparatus,
is shewn in cross section at Fig. 7; the spheres a¹ a² a³ are introduced into the
chambers b b etc. and the force with which they rise in floating will be insufficient
to make them pass out of the chambers in which they are situated.
In case of obstruction, the apparatus may be put in action again without taking
it to pieces by simply introducing an iron wire through the discharge orifice O.
The casing M of the apparatus Fig. 7 is cast in one piece, that is to say, without
joint, and it may be formed of thick glass which would have the advantage of
enabling its action to be seen, and of indicating the water level in the casing. The
apparatus may be applied in all cases where steam or vapour is condensed, such as
steam-heating apparatus and pipes for conducting steam &c.
This apparatus serves as intermediary between the vessel containing the steam
and the orifice for the discharge of condensed water, and all the water of con-
densation from the steam receptacle will pass through it.
Thus it will be seen that this apparatus will itself constitute a supplemental
heating apparatus, and in making it of sufficiently large size, it may of itself
constitute a heating apparatus directly supplied with the steam. In cases where
the water used forms a considerable deposit, there may be introduced between the
cover N and the flange of the casing M a wire gauze diaphragm such as shewn
at V Fig. 8 which may be cleansed from time to time by means of a steam jet
introduced through the pipe r.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The herein described construction of steam trap wherein the steam entering
a closed vessel or chamber, is subjected to successive expansions and corresponding
losses of pressure by being made to pass successively through a series of small
passages alternating with compartments of comparatively large area, the resulting
water of condensation being continuously discharged through a small orifice at
bottom.
2. Constructing steam traps of a closed casing having ledges upon which rest
discs that divide the casing into a number of compartments communicating with
other by means of small passages formed between the discs and the ledges, while
the lowest compartment is provided with a discharge pipe with small orifice for
the escape of the water of condensation substantially as herein described.
3. In apparatus constructed as set forth in the preceding claim, making the
discs or partitions of a material that expands to a greater extent by heat than the
material of which the casing is made.
4. In apparatus constructed as set forth in the second claim, making the par-
titions, whether in the form of discs, plates, or spheres, of a material less dense
than water so that as the water level rises in the casing, its discharge will be

page_text: increased by the rising of the lower partitions from off their seats substantially
as described.
5. Constructing the partition referred to in the preceding claims as spheres of
elastic material, so that when forced through the somewhat smaller upper opening
of a compartment in order to seat on a lower opening thereof, such spheres in
rising when being floated upward by the water of condensation, will not pass
through the said upper opening, substantially as herein described.
6. Constructing the steam trap referred to in the preceding claims of a single
glass casing, so that its action can be seen.