AN IMPROVED CHECK OR STOP VALVE CHIEFLY DESIGNED FOR TITE PROTECTION OF STEAM BOILERS
Year: 1876

page_text: LETTERS PATENT to John Addy Hopkinson and Joseph Hopkinson, both
of the Firm of J. Hopkinson & Co., of Huddersfield, in the County of York,
Engineers, for the Invention of "AN IMPROVED CHECK OR STOP VALVE
CHIEFLY DESIGNED FOR TITE PROTECTION OF STEAM BOILERS."
ealed the 23rd February 1877, and dated the 30th December 18
PROVISIONAL SPECIFICATION left by the said John. Addy Hopkinson and
Joseph Hopkinson at the Office of the Commissioners of Patents on the 30th
December 1876.
JOHN ADDY HOPKINSON and JOSEPH HOPKINSON, both of the Firm of
" AN
J. Hopkinson & Co., of Huddersfield, in the County of York, Engineers.
IMPROVED CHECK OR STOP VALVE CHIEFLY DESIGNED FOR THE PROTECTION OF
STEAM BOILERS."
"
Our Invention relates to an improved check or stop valve which is designed to be
placed in or connected with pipes, passages, or conduits for steam or other fluids,
and which will permit the free current or passage of the fluid in one direction and
will prevent any return or current thereof in the opposite direction through the
valve.
The novel features of the said Invention comprise the application in a peculiar
manner of an clastic or yielding support to the valve and the combination therewith
of passages or apertures for the entrance and exit of the steam or other fluid in such
a manner that the valve opens freely under slight pressure to allow the fluid to pass
freely in one direction but closes automatically under pressure in the opposite
direction and prevents the return of the fluid.
The most important use of our said Invention is its application to steam boilers
arranged in sets or series with their steam spaces connected, and which boilers are
usually provided with a low water discharge or safety valve.
The object of our said Invention in this application or employment of the same is
the automatic and immediate isolation of any boiler from all the others in the set or
series when from low water or other cause the valve of the said boiler should be
discharging its steam. Great inconvenience has been experienced with the present
arrangements of these connected boilers by the absence of any efficient means for
isolating or shutting off the boilers from each other for the reason that if the valve

page_text: of one boiler begins to discharge steam the entrance of steam from the other boilers
prevents any relief or reduction of pressure. But our Invention by providing the
means for isolating the boilers prevents the entrance of steam from the other boilers
into the one whose valve is discharging steam and therefore limits the functions of
each valve to the relief of its own boiler.
We carry our Invention into practise for the above purpose in the following
manner, namely:-We provide each boiler with one of our improved valves which
communicates with the boiler and also with the steam pipe, whereby all the boilers
of the set or series are connected. We prefer to use what we term an inverted valve,
that is to say, a valve which is closed or pressed by upward pressure. The upper
surface of this valve is exposed to the pressure of the steain in the boiler to which it
is attached, and its lower surface or back is exposed to pressure in the said pipe. This
valve as above stated is supported with an elastic or yielding pressure which we
obtain by the use of a float in mercury so arranged that it tends to keep the said
valve closed. While the pressure on the upper surface or inlet side of the said valve,
that is to say, the pressure in the boiler to which this valve is attached, has any pre-
ponderence or excess over the pressure on the other surface or exit side of the valve
and the buoyancy of the float the valve remains open and allows the steam to flow
freely from the boiler into the said pipe. But if the low water safety valve in this
boiler should begin to discharge steam, or if from any other cause the pressure in the
boiler diminishes, the preponderence of pressure in the said pipe immediately closes
the said valve and thereby cuts off the communication of this boiler with the other
boilers.
Instead of an inverted valve we in some instances use a valve which closes by
downward pressure.
Wo do not limit ourselves to any particular form or arrangement of the valve, but
may use any convenient form or arrangement which will act in combination with
a float in mercury to effect the purpose of our Invention.
We also employ our improved check or stop valve for the purpose of preventing
injury to steam boilers or other apparatus by the existence of a vacuum therein; also
as a water relief valve for steam cylinders and for other like purposes.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Addy Hopkinson and Joseph Hopkinson in the Great Seal
Patent Office on the 28th May 1877.
JOHN ADDY HOPKINSON and JOSEPH HOPKINSON, both of the Firm of
"AN
J. Hopkinson and Co., of Huddersfield, in the County of York, Engineers.
IMPROVED CHECK OR STOP VALVE CHIEFLY DESIGNED FOR THE PROTECTION OF
STEAM BOILERS."
Our Invention relates to an improved check or stop valve which is designed to be
placed in or connected with pipes, passages, or conduits for steam or other fluids,
and which will permit the free current or passage of the fluid in one direction and
will prevent any return or current thereof in the opposite direction through the
same.
The novel features of the said Invention comprise the application in a peculiar
manner to the valve of an elastic or yielding support and the combination there with
of passages or apertures for the entrance and exit of the steam or other fluid in such
a manner that the valve opens easily under slight pressure to allow the fluid to pass
freely in one direction but closes automatically when in equilibrium of pressure or
under pressure in the opposite direction and prevents the return of the fluid. This
check or isolating valve also affords the following advantages:-The action of the
said valve is automatic, certain, and noiseless. It opens as much as may be required
for the free flow of all the steam which can pass through the valve aperture, and the
slightest pressure will suffice to open it and to keep it open; but when the steam

page_text: censes to flow through it from the boiler and pressure exists on its opposite side the
valve will at once close gently and without impact. And while the valve will thus
close when the steam ceases to flow through it and when it is placed in equilibrium
of pressure, yet by reason of its peculiar construction it will not be caused to vibrate
by the flow of steam, as its closing tendency is regulated in such a manner as to
prevent instantaneous and violent contact of the valve with its seat. The said
valve will completely isolate any one of a series of boilers, and if the said boiler
should be empty will serve without requiring vigilant watchfulness as a self-acting
stop valve. It will be a protection against a leaky stop valve, or in the case of
mischievous or accidental opening of the stop valve when a boiler is "off" and when
some person may be inside the boiler for cleaning the same, or other purposes. It
will obviate the risk to which boiler inspectors have heretofore been subjected and
entirely relieve them from fear in the prosecution of their duties. It will prevent
loss of steam from all of the boilers in the case of any one of a set or series
becoming leaky or any of the pipes breaking other than the main pipe of the
series.
One of the most important uses of our said Invention is its application to steam
boilers arranged in sets or series with their steam spaces connected, and which
boilers are usually provided with a low water discharge or safety valve.
The object of our said Invention in this application or employment of the same is
the automatic and immediate isolation of any boiler from all the others in the set or
series when from low water or other cause the valve of the said boiler should be
discharging its steam. Great inconvenience has been experienced with the present
arrangements of these connected boilers by the absence of any efficient means for
isolating or shutting off the boilers from each other for the reason that if the valve
of one boiler begins to discharge steam the entrance of steam from the other boilers
prevents any rapid relief or reduction of pressure. But our Invention by providing
the means for isolating the boilers prevents the entrance of steam froin the other
boilers into the one whose valve is discharging steam, and therefore limits the
functions of each valve to the relief of its own boiler.
This improved valve is applicable to all boilers connected in their steamways, and
will be found particularly advantageous in marine boilers.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a vertical central section of a valve constructed according to our
Invention; Figure 2 is a similar section shewing a modification of this valve;
Figure 3 is a horizontal section on the line x, x, Figure 2.
Figure 4 is a plan, and Figure 5 is a side elevation illustating the application of
the said valves to the protection of a series of connected steam boilers.
Figure 6 is a vertical central section of another form of our said valve, herein-
after described.
Like letters indicate the same parts throughout the Drawings.
We carry our Invention into practice for the protection of boilers in the
following manner, namely:-We provide cach boiler A with one of our improved
valves a which communicates with the boiler and also with the main steam pipe b
wherehy all the boilers of the set or series are connected. In Figure 1 we
have shown what we term an inverted valve c, that is to say, a valve which
is closed or pressed upon its seat d by upward pressure; e is the ingress open-
ing or passage leading from the boiler with which the said valve is connected;
f is the discharge opening or passage leading to the said main steam pipe. The
upper surface of this valve c is exposed to the pressure of the steam in the boiler to
which it is attached, and its lower surface or back is exposed to pressure in
the said pipe. This valve as above stated is supported with an elastic or yield-
ing pressure which we obtain by the use of a float g in mercury, so arranged that it
tends to keep the said valve closed. While the steam pressure on the upper surface

page_text: or inlet side of the said valve, that is to say, the pressure in the boiler to which this
valve is attached, has any preponderance or excess over the steam pressure on the
under surface or exit side of the valve and the buoyancy of the float, the valve
remains open and allows the steam to flow freely from this boiler into the said
pipe, but if the low water safety valve in this boiler should begin to discharge
steam, or if from any other cause the pressure in this boiler is diminished, that is to
say, to such an extent that the steam pressure is equal on both sides of the valve, or
if there is a preponderance of pressure in the said inain steam pipe, the said valve
immediately closes, as shewn in Figure 1, and thereby cuts off the communication of
this boiler with the other boilers.
The float is formed of iron or other suitable material, and is attached to the
valve c by a rod or stem g¹; the vessel h which contains the mercury is attached by
its flange h✶ to the flange a¹ on the valve casing as shewn; h¹ is a lid or cover on
the said vessel.
Instead of an inverted valve we in some instances use a valve which closes by
downward pressure, as shewn in Figure 2. In this modification the mercury vessel l
is an annular cylinder placed above the valve c and enclosed within a cap or cover a³
secured by its flange as to the casing a. The valve c is connected by a rod or stem c¹
to a cross bar c; and the latter is attached by the arms to the float g, which is an
annular piece of iron or other suitable metal; is a cover on the vessel k. In this
case the weight of the float y in the mercury tends to close the valve.
The adaptation of mercury as above described prevents vibration or chattering of
the valve. We do not confine ourselves to any particular form or arrangement of
the valve c, but may use any convenient form or arrangement which will act in
combination with a float in mercury to effect the purpose of our Invention.
We also employ our improved check or stop valve for the purpose of preventing
injury to steam boilers or other apparatus by the existence of a vacuum therein.
This application of the said Invention is illustrated in Figure 6. The valve c is
in this case inverted and is attached by the rod or stem g¹ to the float g. The
mercurial vessel is secured within the casing a and is provided with a cover as
shown.
The casing a is attached to the boiler by its flange a* so that the pressure in the
said boiler while steam is kept up therein as well as the buoyancy of the float in
the mercury will tend to close the valve c. But when the boiler is not working and
tho external atmospheric pressure overcomes this internal pressure and buoyancy
the valve opens and admits air to the boiler, thereby destroying the vacuum that
might exist therein.
We also adapt or apply our improved valve to serve as a relief valve for steam
cylinders and for other like purposes. Its application for these purposes will be
readily understood without further description.
Having thus fully described our said Invention, and the manner of performing
the same, we wish it understood that we claim,-
SPEED
First. The application and use of a balanced or supported check or isolating valve
placed in the steam pipes of boilers connected in their steamways for permitting the
flow of steam in one direction only and automatically closing in equilibrium of
pressure or on the flow of steam in the opposite direction for the purpose above
described.
Second. A valve supported by a float in mercury or by other yielding or elastic
pressure, and arranged in combination with passages or apertures on its upper and
lower sides in such a manner that while the pressure on the under side of the valve
preponderates or equals the pressure on its upper side the valve remains closed, but
when there is an excess of pressure on the upper side of the said valve the float
sinks in the mercury and the valve is opened, as and for the purposes above
described.
Third. A valve supported by a float in mercury or by other yielding or elastic
pressure, and so arranged in combination with apertures or passages above and
below the said valve, that while the pressure on its upper side preponderates or

page_text: equals the pressure on its lower side the valve remains closed, but when the pressure
on its lower side preponderates the said float rises in the mercury and the valve is
opened, as and for the purposes above described.
Fourth. The application and use of either of the valves constructed as shewn and
described in connection with a set or series of connected steam boilers for the
purpose of automatically isolating one of the said boilers from the others as above
set forth.
Fifth. The adaptation of our Invention to a valve for protecting boilers and other
apparatus or vessels from the effects of a vacuum therein and for other like
as above set forth.
purposes
In witness whereof, wc, the said John Addy Hopkinson and Joseph Hopkinson,
have hereunto set our hands and seals, this Twenty-sixth day of May, in the
year of our Lord One thousand eight hundred and seventy-seven.
Witness,
ALFRED J. LIVERSEDGE,
Draughtsman,
JOHN ADDY HOPKINSON. (L.S.)
JOSEPH HOPKINSON.
(L.S.)
Huddersfield.