Improvements in Steam Traps.
Year: 1892

page_text: Date of Application, 29th Sept., 1892
Complete Specification Left, 29th June, 1893-Accepted, 29th July,
1893
PROVISIONAL SPECIFICATION.
Improvements in Steam Traps.
I CHARLES EDWARD HEARSON of No. 5 Templar Street Camberwell in the
County of Surrey Engineer do hereby declare the nature of this invention to be as
follows :-
A steam trap constructed according to my invention consists of a case or box
adapted to be connected to steam apparatus from which the escape of water of
condensation is required the said case having inlet and outlet passages communi-
cating with its interior in which are mounted a valve and an expansible and
collapsible capsule, containing a liquid which boils at a temperature slightly
higher than that at which the water of condensation is required to escape, the
expansion and collapsing of which capsule when the steam trap is in use so governs
the position of the said valve as to cause the inlet passage of the trap to be opened
and closed as and when required. The said trap is also furnished with a strainer
through which the water of condensation passes on its way to the interior of
the case.
The construction and arrangement of the several parts of the said steam trap are
herein after described.
The case of the trap is formed of metal or other suitable material and in several
parts secured together by screws.
The valve consists of a conical ended bolt or short rod of the form of a cylinder
having flat faces cut on its sides. This valve is mounted and is capable of moving
endwise in the inner end of the inlet passage of the case of the trap which passage
is circular in transverse section and has formed within it an annular projection or
flange which constitutes the seating for the conical acting end of the said valve.
The capsule is constructed as described in the Specification of Letters Patent
No. 13178 granted to me and bearing date the 4th day of August 1891 and is
mounted on one face of a plate having a screwed stem projecting from its other
face which stem engages with the inner end of a screwed hole formed in a portion of
the case of the trap in line with the inlet passage the other end of which hole
receives the screwed stem of a plug or stopper the head of which projects outside
the case of the trap. This plug closes an aperture in the case of the trap which
admits of access to the working parts of the trap for the purpose of adjusting (as
herein after described) the positions of the said parts when the parts of the case
are secured together. To prevent corrosion of the capsule by action on it of the
water passing through the trap I make the said capsule of a less oxidizable metal
than that of which the other parts of the trap are made and in order to prevent
injury to the capsule consequent on electrolytic action between the metal thereof
and the solder with which the joints are made I coat the completed capsule with
metal of the same kind or with a less oxidizable metal preferably by electro
deposition.
The strainer consists of a wire gauze cap supported by a tubular plug screwed in
the outer end of the inlet passage of the case of the trap the outer faces of which
plug have channels formed in them to permit of free passage to its interior of the
water of condensation which passes through the wire gauze of the strainer and
through the hollow of the said tubular plug on its way to the interior of the trap.
After the working parts of the trap have been placed within the case of the trap
and the parts of the said case have been secured together the said working parts
are adjusted to the proper positions for action by turning the screwed stem of the
plate on which the capsule is mounted in the direction necessary to cause the said
plate and the capsule to advance toward the inlet passage until the valve mounted

page_text: in the said passage is pressed to its seating therein by contact of the capsule with
the non-acting end of the said valve. The said plate is then slightly withdrawn so
as to permit of the required play of the valve by giving the screwed stem of the
said plate one complete turn in the reverse direction.
When the trap is connected to steam coils or other steam apparatus from which
water of condensation is required to be allowed to escape the action of the said
trap is as follows. While there is no accumulation of water in the part of the
apparatus to which the trap is applied the heat of the steam in the said apparatus
acting on the liquid in the capsule causes ebullition and complete vaporization of
the said liquid and consequent expansion of the said capsule the valve being
thereby pressed to its seating in the inlet passage which is thus closed. When
water of condensation accumulates in the said part of the steam apparatus the
contents of the capsule condense in consequence of the lower temperature of the
said water and the capsule being then in the collapsed state the valve retires from
its seating in the inlet passage and allows the water of condensation to escape
through the trap the said water passing through the strainer and the inlet passage
and the valve seating to the interior of the case of the trap and thence through the
outlet passage thereof. The flats cut on the sides of the bolt-shaped valve permit
the water to pass the said valve which as hereinhefore stated is mounted in the
inlet passage.
An advantage attending the use of steam traps constructed as hereinbefore
described is that air passes freely through them from the steam apparatus to which
they are applied while the said apparatus is cold and steam is being admitted
thereto.
Dated the 29th day of Sentember 1892.
W. T. WHITEMAN,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Steam Traps.
Í CHARLES EDWARD HEARSON of No. 5 Templar Street Camberwell in the
County of Surrey 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 :-
A steam trap constructed according to my invention consists of a case or box
adapted to be connected to steam apparatus from which the escape of water of
condensation is required the said case having inlet and outlet passages communicating
with its interior in which are mounted a valve and an expansible and collapsible
capsule containing a liquid which boils at a temperature slightly higher than that
at which the water of condensation is required to escape, the expansion and
collapsion of which capsule when the steam trap is in use so governs the position
of the said valve as to cause the inlet passage of the trap to be opened and closed
as and when required. The said trap is also furnished with a strainer through
which the water of condensation passes on its way to the interior of the case.
Figure 1 of the accompanying drawings is a plan view of a steam trap constructed
according to my invention;
Figure 2 is a section taken on the line A A Figure 1 and
Figure 3 is a plan view of the lower part of the trap shown separated from the
upper part.
The same letters of reference indicate the same parts in the said Figures 1, 2
and 3 and in the other figures of the accompanying drawing hereinafter
referred to.
The construction and arrangement of the several parts of the said steam trap
are hereinafter described.
The case of the trap is formed of brass or other cast metal or other suitable

page_text: material in two parts marked respectively a, b which are secured together by
screws c, c.
The valve consists of a conical ended bolt or short rod d of the form of a
cylinder having flat faces e, e cut on its sides. The said valve is mounted and is
capable of moving end wise in the inner end of a passage f formed in the part a of
the case of the trap which passage constitutes the inlet of the trap and is circular
in transverse section and has formed within it an annular projection or flange g
which constitutes the seating for the conical acting end of the valve d.
h is the expansible and collapsible capsule which is of the kind described in the
Specification of Letters Patent No. 13178 granted to me and bearing date the
4th day of August 1891 and is supported by a plate i having a screwed stem j
formed thereon which stem engages with the inner end of a screwed holek formed
in the part of the case of the trap in line with the inlet passage f the other end of
which hole receives the stem of a screw the head of which projects outside the
case of the trap and binds thereto the part m in which is formed a nozzle n
constituting the outlet of the trap.
The strainer consists of a wire gauze cap o supported by a hollow or tubular
plug p which is screwed in the outer end of the inlet passage of the trap through
the hollow of which plug the water of condensation passes to the interior of the
trap. In order that the water passing through the meshes of the strainer o may
flow freely to the interior of the hollow plug p channels q, q are formed around the
said plug and other channels r, rare formed longitudinally therein intersecting the
channels g, q and other channels s, s are formed in the outer end of the said
plug which channels s, s connect the channels r, r with the hollow of the said
plug.
After the working parts of the trap have been placed within the case of the
trap and the parts a, b of the said case have been secured together the said working
parts are adjusted to the proper positions for action by turning the screwed stem
of the plate i on which the capsule h is mounted in the direction necessary to cause
the said plate and the capsule to advance toward the inlet passage until the
valve mounted in the said passage is pressed to its seating 9 by contact of the
capsule with the non acting end of the said valve. The said plate is then with-
drawn sufficiently to permit of the required play of the valve by giving the screwed
stem of the said plate one complete turn in the reverse direction.
When the trap is to be used it is connected to the apparatus from which water
of condensation is required to be allowed to escape by means of the screw thread
around the part in which the inlet passage f is formed. The action of the said
trap when thus connected is as follows;-While there is no accumulation of water
in the part of the apparatus to which the trap is applied the heat of the steam in
the said apparatus acting on the liquid in the capsule causes ebullition and complete
vaporization of the said liquid and consequent expansion of the said capsule the
valve d being thereby pressed to its seating g in the inlet passage f which is thus
closed. When water of condensation accumulates in the said part of the steam
apparatus the contents of the capsule condense in consequence of the temperature
of the said water being lower than the boiling point of the liquid in the capsule
and the capsule being then in the collapsed state the said valve d retires from its
seating and allows the water of condensation to escape through the trap the said
water passing through the strainer o and the inlet passage f and the valve seating g
to the interior of the case of the trap and thence through passages ** in the
part to the outlet n. The flats e e cut on the sides of the bolt shaped valve d
permit the water to pass the said valve.
In cases where it is desired that water and sediment may be blown out of the
steam apparatus to which the trap is applied without allowing them to pass through
the trap this may be provided for by applying to the upper part thereof a cap or
cover having two sockets formed in it to one of which the steam apparatus is
connected and to the other of which a tap or cock is connected.
Figure 4 of the accompanying drawings is a plan view of a cap or cover of

page_text: suitable form and Figure 5 is a vertical section of a steam trap constructed
according to my invention having the cap or cover applied thereto.
Referring to the said Figures 4 and 5 t is the cap or cover and u v are the sockets
to which the steam apparatus and the cock are respectively connected when the
trap is to be used.
w to are screws which serve to connect the cover to the trap
and also to connect the parts a and b of the trap together. The parts of the trap
illustrated in the said Figure 5 are in all respects the same as those hereinbefore
described with reference to Figures 1 and 2 except that grooves or channels are
formed in the part of the trap in which the inlet passage f is formed and the
strainer o is placed over and around the said part instead of being placed over and
around a grooved or channelled plug secured in the said part as shown in the said
Figures 1 and 2.
In making the capsule I proceed as follows;-I take two pieces of thin sheet
metal of the form shown in Figure 6 and turn up the edges by bending the metal
at the parts indicated by broken lines in the said Figure 6 the shape of each of the
pieces of metal when so treated being that of a shallow tray the sides of which
stand at about right angles to the base. I then place in the hollow of one of the
tray shaped pieces of metal a piece of blotting paper of a size rather less than the
space enclosed by the broken lines in Figure 6 and double the turned up edges of
the metal down flat on the paper as shown in Figure 7. In the bottom of the other
tray and at or near the middle thereof I make a small hole to admit of insertion of
the required liquid when the parts of the capsule are connected as hereinafter
described and in the said tray I place a square frame of stout sheet metal which
may be of the form shown in face view and transverse section in Figure 8 and the
outer dimensions of which frame are slightly smaller than those required for the
finished capsule. Over the said frame I place a square piece of blotting paper of
about the same size as the frame and double the turned up edges of the thin sheet
metal down flat on the paper. I then place the two parts together with the turned
-over-edges-in-contact as illustrated in Figure 9 which is a sectional view of the said
two parts drawn to a large scale the thin sheet metal being marked a the blotting
papery and the metal frame z. I then solder the said two parts together along
their edges and to ensure perfect sealing of the capsule at the corners where the
edges of the thin sheet metal are outward I file off the sharp angles at the said
parts and apply a little solder to the filed surfaces. That face of the capsule on
which the valve & bears is strengthened by means of a disc of sheet metal /* which
may be soldered to the thin sheet metal before turning up the edges thereof as
hereinbefore described. I then introduce the required liquid into the capsule
through the hole formed for that purpose and hermetically seal the capsule by
closing the said hole with solder.
The liquid selected for use should be such as has a boiling point a degree or two
above the temperature at which the capsule is required to act and the quantity of
liquid enclosed in the capsule should be no more or but little more than sufficient
when completely vaporized to cause expansion of the capsule to the full extent
required to press the valve to its seating as if an appreciably larger quantity be
used a sudden rush of steam into the trap will be liable to cause distension of the
capsule to such an extent that the metal of the outer part thereof will be ruptured
or permanently distorted.
For a capsule of the size shown in Figures 2 and 3 of the accompanying
drawings (namely one inch and a half square) and where the valve is required to
have a play of one sixteenth of an inch and the water of condensation is required
to escape at a temperature of one hundred and eighty degrees I have found that
ten minims of a mixture consisting of two parts of alcohol and three parts of water
acts satisfactorily.
If the trap be required to act at a lower temperature a liquid having a lower
boiling point must be used and if a greater play of the valve be required a larger
quantity of liquid must be enclosed in the capsule and rice versa.
The office of the blotting paper being merely to retain the liquid within the

page_text: capsule while the hole through which the liquid is introduced is being hermetically
closed by soldering it will be obvious that any other convenient absorbent fabric or
material may be used in lieu of paper.
To prevent corrosion of the capsule by action on it of the water passing through
the trap I make the said capsule of a less oxidizable metal than that of which the
other parts of the trap are made and in order to prevent injury to the capsule
consequent on electrolytic action between the metal thereof and the solder with
which the joints are made I coat the completed capsule with metal of the same kind
as that of which it is made or with a less oxidizable metal preferably by electro-
deposition. For example if the parts abdi mlp of the trap be made of brass
copper will be a suitable metal from which to make the capsule and the metal used
for coating the capsule may be copper or silver.
An advantage attending the use of steam traps constructed according to my
invention is that air passes freely through them from the steam apparatus to which
they are applied while the said apparatus is cold and steam is being admitted
thereto.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that I claim
as my invention of "Improvements in Steam Traps";-
-
First. The combination with a valve arranged and acting substantially as herein-
before described of means for actuating the said valve consisting of a hermetically
sealed expansible and collapsible case or capsule containing a liquid which boils at
a temperature slightly lower than that at which the valve is required to be closed
the quantity of the said liquid contained in the said case or capsule being such that
complete vaporization of the whole of the said liquid will produce no greater
expansion or but slightly greater expansion of the capsule than is required to press
the said valve against its seating.
Secondly. The use in a steam trap substantially as herein before described of an
expansible and collapsible case formed of less oxidizable metal than that of the
other parts of the trap.
Thirdly. The use in a steam trap substantially as hereinbefore described of an
expansible and collapsible case coated with less oxidizable metal than that of the
other parts of the trap.
Fourthly. The use in a steam trap of a strainer constructed substantially as
hereinbefore described and illustrated in the accompanying drawings.
Dated the 29th day of June 1893.
W. T. WHITEMAN,
Agent for the Applicant.