IMPROVEMENTS IN APPARATUS TO BE USED IN CONNECTION WITH LOCOMOTIVE AND OTHER BOILERS FOR RELIEVING THE SAME FROM PRESSURE, HEATING THE FEED WATER, REGULATING THE DISCHARGE OF THE WASTE STEAM, AND FOR OTHER LIKE PURPOSES
Year: 1878

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN APPARATUS TO BE USED IN CONNECTION WITH LOCOMOTIVE
AND OTHER BOILERS FOR RELIEVING THE SAME FROM PRESSURE, HEATING THE
FEED WATER, REGULATING THE DISCHARGE OF THE WASTE STEAM, AND FOR
OTHER LIKE PURPOSES." A communication from abroad by Henry G. Ashton,
of Boston, Massachusetts, United States of America.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at
the Office of the Cominissioners of Patents on the 22nd May 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. IMPROVEMENTS IN APPARATUS TO BE USED IN
CONNECTION WITH LOCOMOTIVE AND OTHER BOILERS FOR RELIEVING THE SAME
FROM PRESSURE, HEATING THE FEED WATER, REGULATING THE DISCHARGE OF THE
WASTE STEAM, AND FOR OTHER LIKE PURPOSES." [A communication from abroad
by Henry G. Ashton, of Boston, Massachusetts, United States of America.]
This Invention relates to the relieving of steam boilers when under too great
pressure, and also to the conducting of the waste steam to any desired point, as,
for example, to the feed water tank, to heat the water, or to the smoke box or
chimney; and it consists in certain improvements in apparatus for heating the feed
water so that the steam may be conducted to the smoke box as well as to the feed
water tank, and also in certain forms of safety valves with which such apparatus
may be best used.
The said Invention comprises the combination of a pipe with a safety valve
having a chamber partitioned off from the top of the valve, so that the outer

page_text: surface of the valve is exposed to atmospheric pressure and with the feed water
tank, one end of the said pipe opening into the said chamber and the other end
into the feed water tank. The said pipe has orifices near the surface of the water
and at its lowest parts in the feed water tank to keep the said pipe free from water.
When steam in the said chamber and pipe condenses the air can enter the pipe
through the one orifice in one direction and through the chamber in the other
direction without preventing the escape of the water of condensation from the
other orifice. The said pipe is closed at its rear end and provided with a series of
small holes to form a distributor of steam and prevent noise.
The safety valve pipes are provided with a three-way cock, and are so constructed
and arranged that the escape steam from the safety valve may be carried in either
one of two directions, that is to say, to the feed water or to the smoke box.
The said Invention also comprises the combination of a seat casing and outlet
pipe with a safety valve fitted so closely as to prevent the escape of the waste
steam past the periphery of the said valve, and to compel the whole or nearly the
whole of the waste steam to pass through the outlet pipe, the said valve being open
to the atmospheric pressure on its outer surface. And in combination with this
safety valve, seat casing, and outlet pipo I use an adjusting valve for varying the
area of the said outlet pipe.
There is another valve termed a "pop valve" having a chamber in combination
with a seat or cylinder and casing. This valve has a perforated annular projection
and chamber in combination with the said seat.
When the steam in the boiler begins to exceed the desired pressure, and forces the
said valve slightly off its seat, the steam which escapes enters the chambers; but
as it cannot escape from that chamber except through the holes (and a small portion
of it under the thin edge) it will there produce a pressure aiding in lifting the
valve, making a valve which rises suddenly, and gives a large area for the escape of
the steam, relieving the boiler speedily and effectually.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 22nd
November 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN APPARATUS TO BE USED IN
CONNECTION WITII LOCOMOTIVE AND OTHER BOILERS FOR RELIEVING THE SAME
FROM PRESSURE, HEATING THE FEED WATER, REGULATING THE DISCHARGE OF THE
WASTE STEAM, AND FOR OTHER LIKE PURPOSES." A communication from abroad
by Henry G. Ashton, of Boston, Massachusetts, United States of America.
This Invention relates to the relieving of steam boilers when under too great
pressure, and also to the conducting of the waste steam to any desired point, as,
for example, to the feed water tank, to heat the feed water, or to the smoke box or
chimney; and it consists in certain improvements in apparatus already known for
heating the feed water, so that the steam may be conducted to the smoke box as
well as to the feed water tank; and also in certain forms of safety valves with
which such apparatus may be best used.
This apparatus is very simple, and will be readily understood by reference to the
Drawings, in which,-
Figure 1 is a side elevation of part of a locomotive and its tender; Figure 2 is a
transverse section of the same.
Figure 3 shews portions of Figure 1 detached and drawn to an enlarged scale.
In these Figures a locomotive boiler A is shown, to which is attached the
"tender" B, wherein is the feed water tank B'; C is the safety valve, which has a
proper chamber around it for confining the steam which has escaped from the boiler;
D, D', is the pipe which carries the steam into the feed water tank, where it is
discharged into the water which is to be used to feed the boiler. In the pipe D¹ at
its lowest point is a small aperture d, and at a point above and near the surface of
the water is a second aperture, shown at d. The purpose of these aportures is to
keep the pipe D free from water. When used together the aperture & may be very
small, so small that the quantity of steam which escapes through it is practically
nothing.
When the steam in the pipe D, D', condenses the water of condensation collects
at the lowest part of the pipe and escapes through the aforesaid aperture d. The
condensing of the steam also causes a partial vacuum in the pipe D, D', and inas-
much as the water in the tender is often only a few inches below the bend of the
pipe D' the partial vacuum in pipo D, D', will frequently be great enough to cause
the water in the tender to flow over this bend, and for this reason I use the
aperture d, which can be made large enough, say one-eighth of an inch in diameter,
to supply all the air required.
Another feature of this apparatus relates to the distributer used in the tender.
The pressure in the chamber around the safety valve depends upon the pressure in
the boiler, the volume of steam which escapes from the boiler, the area of the
pipe D, D', the number of elbows in that pipe, the area of the outlets froin that
pipe, and also the depth of the water in the tender; but this last is of so little
consequence that it may be disregarded.
If no distributer be used, that is, if the end of the pipe D' be open, the steam
will make a rumbling noise in the tender, which is so loud as to be very objection-
able. This is the case whenever the end of the pipe is open, whether there be holes
in the pipe or not.
This part of the Invention consists in the combination with the safety valve and
the pipe D, D, of a pipe closed at its outer end and perforated with numerous
small holes, the total area of these holes being sufficient to allow the proper escape
of the steam. These holes are commonly made sixty in number, each about three-
eighths of an inch in diameter. Their number depends upon their size, the size of
the pipe D, D', and the volume and pressure of the steam which escapes from the

page_text: valve. For convenience, and because of the difficulty of properly determining the
number of these holes of given size without a test, I prefer to make a greater
number than will be required, and to use a sleeve or cap d by which enough of
them can be covered for the proper adjustment.
In order that when desired the escape steam may be shut off from the feed water
tank and the safety valve still afford proper relief to the boiler, there is connected
to the pipe D a pipe D² which leads to the smoke box E, the end of which pipe is
generally turned downward and perforated, as shewn in Figure 2, and capped so
that the steam will not be discharged in a single large jet into the smoke box, but
in a series of small jets escaping as a vapor from the smoke stack without materially
affecting the draft.
Where the pipes D, D', and D2 join, I place a three-way cock, the best form of
which, for this purpose, is shown in detail in Figure 3, in which F is the plug
controlled by the engineer by means of the lever f, and links ƒ³, ƒ³, ƒ³, ƒ³, being
stops to prevent too great motion being given to the valve.
J
Figure 3 shows the valve in position to allow the steam to flow into the feed
water by the pipes D, D¹. If the access of steam to the feed water is to be
prevented for any reason the handle f, and by it the plug F, is moved into the
position indicated by the dotted lines, thus allowing the steam a passage through
the pipes D, D³, to the smoke box. By this arrangement the steam, although at a
high tension, often one hundred and thirty pounds to the square inch, when it
escapes, is reduced to a low tension (about ten or fifteen pounds) when it enters the
smoke box.
It will be seen that these two devices above described need not necessarily be
used together. Either system of pipes D, D', discharging into the feed water tank,
or D, D2, discharging into the smoke box, may be used alone and with advantage,
for by either system of pipes all the disagreeable noise which is caused by the steam
escaping from the safety valve directly into the open air is done away with, and all
danger that horses will be frightened by the sight as well as the sound of escaping
steam is obviated.
It will also be seen that the systems above described are not confined to loco-
motives only; they will be found advantageous for use with any steam boilers.
In order to confine the waste steam so that it may be conveyed away by the
pipe D, a cover is required over the valve, from which the waste steam passes by
incans of the pipe D to the point where the steam is to be discharged. It will be
seen that if the waste steam is allowed to collect in a chamber around and on the
top of the ordinary Safety valve, from which it is only allowed to escape by means
of a pipe of comparatively small diameter, the steam will soon exert a pressure in
the chamber and materially increase the load on the valve so that the valve will
close, and so long as any great amount of steam is in the chamber will remain
closed. An ordinary valve under these circumstances will not properly relieve the
boiler, and for this reason I use the safety valve, whose several forms are herein
described, and in which the upper surface of the valve proper is open to the
atmosphere, and in which the waste steam does not ascend in a body past the edges
of the valve, but is discharged by means of a pipe from the chamber, part of the
walls of which are formed by the under and lateral surfaces of the valve. This
kind of valve is termed an "under discharge" valve, and three simple forms of it are
shown in section in Figures 4, 5, and 6, in which G is the valve proper, ground upon
its seat in the usual way; D is the seat or bushing, which is secured to the boiler
or other reservoir of power in the usual way; and g¹ represents the spring or means
of keeping the valve upon its seat until the pressure in the boiler exceeds the
desired amount. In all these respects the valve does not differ from those in
general use.
Around the seat in Figure 4 a chamber D³ is formed, the part D of the casing
forming the bottom of this chamber, the part D of the casing forming its sides,
and the valve G completing this chamber, so that the steam which passes the seat
of the valve enters this chamber and cannot escape from it except by the outlet

page_text: pipe D which leads from the chamber to any desired point. This chamber D³, part
of which is formed by the valve itself in combination with the pipo D, is the
distinguishing characteristic of this new safety valve.
The operation of this valve is as follows, that is to say-When the pressure
begins to exceed the amount at which the valve is set, the valve lifts slightly from
its seat, and the steam escapes into the chamber D³, creating a pressure in that
chamber, which pressure is greater or less, according to the pressure of the steam in
the boiler, the amount of rise of the valve, and the size of the outlet D. Thus if
the valve be raised, say, one hundred and twenty-eighth part of an inch from its
scat, and the circumference of the valve at its seat be, say, six inches, the inlet
aperture through which the steam enters the chamber D³ will be nearly six one hun-
dred and twenty-eighth parts of a square inch, and the pressure of the steam in
the chamber D³ will then depend upon the pressure of the steam in the boiler and
the size of the outlet aperture D, through which the steam escapes from the
chamber D³, as it is clear that steam of a given pressure entering a small chamber
through a given aperture, and escaping from the same chamber by a given aperture,
will produce a given pressure in the small chamber. This pressure in the chamber D³
soon becomes sufficient to lift the valve high enough to freely relievo any boiler,
as the area of the valve which is exposed to pressure is greater when the valve is
uff its seat, and the chamber Ds is filled with steam under pressure, than when the
valve is on its sent, and the steam thereby prevented from entering the chamber D³.
It will now be obvious that the pressure in the chamber D³ can be inade moro
or less with a given pressure of steam in the boiler by making the outlet pipe D
smaller or larger, and consequently that the total pressure tending to raise the valve
and keep it off its seat can be very accurately adjusted by changing the size of this
outlet pipe D relatively to the size of the inlet aperture, that is, the aperture
through which the steam escapes from the boiler and into the chamber D³, the area
of which aperture depends upon the size and rise of the valve.
With this safety valve, when the outlet D is of the proper area relatively to the
area of the inlet aperture, the steam begins to "simmer," that is to say, to cscape
very slightly, as soon as the pressure in the boiler reaches the point at which the
valve is set, and a rise of a few ounces to the square inch above that pressure forces
up the valve G high enough to cause the chamber D³ to be filled with stoam under
pressure, thereby bringing a greater pressure to bear, tending to lift the valve, and
this greater pressure lifts the valve higher, and thus increases the area of the inlet
aperture, which increases the flow of steam into and the pressure in the chamber D³,
and consequently the valve "pops" or rises largely and suddenly very soon after
the pressure passes the point at which the valve is set.
In practice the rise of the valve is regulated by the cap G¹, which screws into the
part D of the casing, this cap being set at the distance desired from the valve, so
that the valve will abut against the cap when it has risen the distance desired; the
greater the riso the more freely is the boiler relieved. This valve has worked well
with a rise of one-quarter of an inch, making the escape aperture for the steam
about one and a half square inches in area; this area is larger than is necessary for
any locomotive boiler. The cap G' is commonly set to allow the valve to rise about
one-tenth of an inch.
After the valve has "popped" the escaping steam continues to pass through the
chainber D³ until the pressure in the boiler reaches the point at which the valve
was set; but as the pressure in the boiler diminishes so does the pressure in the
chamber D³, and consequently the total pressure tending to hold the valve up is so
much diminished that the spring g' begins to force the valve toward its seat; but
the least motion of the valve toward its seat diminishes the area of the inlet
aperture through which the steam enters the chamber D³, and consequently
diminishes the pressure in the chamber D³, so that the valve closes very rapidly
after it once starts, and if the proportion between the area of the inlet and outlet
apertures into and from the chamber D³ be correct, the valve will close when the

page_text: pressure in the boiler is reduced a few ounces to the square inch below what it was
when the valve opened.
In Figure 4 of the Drawing the valve G is shewn cup shaped. This is for the
purpose of enlarging the chamber D³, and it is obvious that this is merely a matter
of form, as illustrated in Figures 5 and 6, the principle of this valve consisting in
the use of a chamber, part of the wall of which is formed by the valve itself, and
having an outlet pipe leading from it to conduct the waste steam either into the
feed water or to any other point desired.
The pipe D may be made of the proper area in the machine shop when the valvo
is to be used for a given pressure of steam, but as this requires very nice workman-
ship to get the best effects, this pipe D is in practice made larger than can be
required, and an adjustable valve D is used, by which the area of the pipe D can
be not only accurately adjusted, but can be varied to suit different pressures of
steam. This adjustable valve D, in combination with the pipe D and valve G,
constitutes an important feature of this Invention.
When the valve G first leaves its seat there will be a slight escape of steam
between the valve and the walls, and this slight escape would continue were it, not
for the cup G', which stops it almost wholly; but the valve G should fit so nicely
in the wall D5 of the casing as to make so slight a space between them that the
amount of steam which escapes will be very slight, and it is preferred to have a
slight space in order that the air may enter the chamber D³ after the valve G
closes, and as the steam in the chamber D³ and in the pipe leading from it to tho
water in the feed water condenses, in order to act with the aperture d, Figure 1, in
preventing the formation of a vacuum, which would cause the water from the tank
to fill the chamber D³, this being objectionable for some reasons.
Figures 5 and 6 illustrate modifications in the form of this valve, and will bo
readily understood without further description.
Another form of "under discharge" valve is shown in Figures 7 and S. The
chief peculiarity of this valve is that the "pop" is caused by the accumulation of
steam in a chamber, the walls of which are formed by the valve and its seat, and it
is independent of the diameter of the pipe D, and hence with this form of valve
an adjustable valve like that shewn at D, Figure 4, need be used. As this form
of valve is the best known for relieving the boiler, whether it be used with or
without the pipe D and apparatus first above mentioned, it is shown in full in the
Drawing.
The bushing is provided with a cover or casing, which for convenience is made
in two parts v and n, and within this casing is a cylinder w. his the valve; its
spindle supports one end of the spring y, the other end of which is pressed upon
by the nut, which is controlled by the screw m, a shoulder on which bears against
the under side of the cover n. The load of the valve is increased by turning the
screw m, and thereby forcing the nut 7 nearer to the valve and tensioning the
spring y. The stress of this spring is exerted upon the valve through the spindle k.
The said cover n is firmly secured to the casing v, and it is preferred to form the
cylinder win one piece with the cover n, so that when the cover is put in place the
cylinder will be in the right relation to the valve. Besides the central hole in
the cover n (through which the upper part of the screw m passes) other holes are
provided in order to give a free outlet to the air in the chamber c, and to such
steam as passes into that chamber while the valve is rising. To prevent the
entrance of cinders and dirt through these holes the perforated cover p is used. It
is better to make the lower end of the cylinder w a little larger in diameter than
the rest of it, as shown, in order to form a shoulder or cap.
To prevent tampering with the valve a hood q is placed over the upper part of
the screw m, and held in place by a screw 7, which has holes through its head to
receive a wire, the wire passing around the hood g or through a lug forming a part
of the hood, and having its ends sealed so that the screw 7 cannot be removed with-
out breaking the seal or cutting the wire.

page_text: The valve h is provided with an annular projection ' of the form shewn. Its
thin edge comes close down to the bushing or seat ; when the valve is closed, thereby
forming a chamber 8. A series of holes lead from this chamber for the purpose
now to be explained.
r
When the steam in the boiler begins to exceed the desired pressure and forces the
valve slightly off its seat, the steam which escapes enters the chamber 8, but as it
cannot escape from that chamber except through the holes (and a small portion of
it under the thin edge ¹) it will there produce a pressure, aiding in lifting the valve,
making a valve which rises suddenly and gives a large area for the escape of the
steam, relieving the boiler speedily and effectually, herein-aftor called a pop
valve." It will be observed that as the valve rises and as the steam consequently
escapes more freely the outlet from the chamber s under also enlarges, and as the
valve descends this outlet decreases. Without these holes the valve shewn would
not close until the pressure in the boiler had fallen much below the pressure when
the valve rose; but if these holes be of the proper area the valve will close, when
the pressure in the boiler is decreased less than two pounds to the square inch;
that is, this valve will prevent the pressure exceeding the point at which the valve
is set to rise more than one or two pounds, and will close when the pressure in tho
boiler has fallen less than two pounds below that at which the valve is set to rise.
The total area of these holes must be adapted to the size of the valve, the pressure
of the steam in the boiler, and the stiffness of the spring.
Each valve should be tested before it is used, and to obtain the best results the
total area of these holes should be carefully adjusted to the spring used, no two
springs being exactly alike.
The valves above described may be used as well without as with the pipe D and
its adjuncts.
The valve shown in Figures 7 and 8 is particularly well adapted for use in
relieving steam boilers. It rises promptly, and if properly adjusted gives adequate
relief to the boiler, and closes when the pressure in the boiler has fallen not more
than two pounds below that at which the valve was set to rise.
At D7 in Figure 7 is shown the part of the casing to which the pipe D would bo
attached when used.
The main feature of this part of the Invention consists in the combination of a
valve so arranged with a small chamber 8, into which the steam enters as soon as
the valve begins to rise, that the valve is lifted considerably and suddenly by the
pressure of the steam in the said chamber aiding the pressure in the boiler to over-
come the force of the spring, with a hood or casing to receive the escaping steam
and cylinder into which the valve rises, making what is termed an "under dis-
charge pop valve;" that is to say, a valve in which the access of the escaping
steam to the outer surface of the valve is prevented by a cylinder or inner casing,
into which the valve rises, and in which it fits closely enough to prevent the
entrance of any considerable portion of the escaping steam.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,-
First. The combination of parts comprising the safety valve, having a chamber
partitioned off from the top of the valve so that the outer surface of the valve is
exposed to atmospheric pressure, the feed water tank, and the pipe, with one end
of the same opening into the said chamber, and the other into the feed-water tank,
all as above described and for the purpose specified.
Second. In combination with the safety valve and the feed-water tank the pipe
having an orifice in it near the surface of the water in the feed-water tank, and an
orifice at the lowest part of it, as shewn and described, and for the purposes
specified.
Third. The combination of parts comprising the feed-water tank and the safety
valve, having an opening through which the air can enter the steam chamber, the
pipe having the two orifices, one at the lowest part of the pipe and the other near

page_text: the surface of the valve in the tank, whereby when its steam in the said chamber
and pipe D' condenses the air can enter the said pipe through one orifice in one
direction,, and through the chamber in the other direction, without preventing
the escape of water of condensation from the other orifice, all as shewn and
described.
Fourth. The combination of the safety valve with the smoke box by means of
the said pipes, as and for the purposes set forth.
Fifth. The combination of the said safety valve, the pipe D, the cock, and the
pipes D' and D², constructed and arranged as shewn, in order that the escape steam
from the safety valve may be carried in either one of two directions, as above set
forth.
Sixth. In combination with the seat, the casing, and the outlet pipe D a safety
valve G, fitted so closely as to prevent the escape of any considerable part of the
waste steam past the periphery of the said valve, and to compel the whole, or
nearly the whole, of the waste steam to pass through the outlet pipe, and open the
same to the atmospheric pressure on its outer surface, as above set forth.
Seventh. In combination with the safety valve the seat D*, casing D³, outlet
pipe D, and the adjusting valve, as above described, and for the purpose specified.
Eighth. The valve h, having the chamber in combination with the seat, the
cylinder, and the casing, arranged to operate as described, and having the perforated
annular projection in combination with the said chamber and seat, as above set
forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty-second day of November, in the year of our Lord
One thousand eight hundred and seventy-eight.