Improvements in or relating to Compressed Gas Vessels.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in or relating to Compressed Gas Vessels.
ALFRED SWEETSER, of "Garwood," Rosendale Road, Herne Hill, in the County
of Surrey, Consulting Engineer, ANDREW PRINGLE, of Cromwell House, Bexley
Heath, in the County of Kent, Gentleman, do hereby declare the nature of this
invention to be as follows:-
This invention has for its object an improved method of closing the ends of
vessels for the storage of compressed gases, so that the inside shall be easier of
access than heretofore. Another feature of our invention is, that it shall be
impossible to burst the vessel explosively by the pressure of the contained gas,
even from the ignition of an explosive mixture of gases.
Our invention also includes other improvements in detail as hereinafter set
forth.
In carrying out our invention we take a length of tube the diameter of the
vessel required, the ends are closed by loosely fitting caps provided with a central
hole for a bolt, the whole length of the vessel, and nuts to hold caps firmly in
their places. To render these ends gas tight, a double flanged ring of metal,
gutta percha, or other suitable material forming a cup or gas check, is threaded
on the central bolt before the caps are screwed on, the internal pressure of the
gas pressing one flange of the cup or gas check against the plain portion of the
central bolt, and the other flange against the internal walls of the vessel. The
sectional area of the aforesaid central bolt is so proportioned in respect to the
area of the internal surface of the caps, that in case of an excessive pressure in
the vessel the central bolt stretches before the elastic limit of the walls of the
vessel is reached so that the caps act like safety valves, allowing the gas to
escape. We sometimes utilise the central bolt as the screw valve for the outlet
of the gas, by drilling it up and tapping for valve spindle, and by screwing a
gland on the end of the bolt so forming a stuffing box. The seating of the valve
for making connection, for filling or discharging the gas, instead of being a
plain cone as usual, is formed with a projecting ring or shoulder which being
steel cuts through any inequality or foreign matter on the cone end of the
regulator, or other connection, so making a better joint. When only one end
of the vessel is required to be closed according to this invention, or to reduce
the area of the cap, we sometimes turn in or swage down the edge of the tube
forming the body of the vessel and instead of the central bolt extending the
whole length of the vessel it terminates in a bridge piece or collar, taking a
bearing on the turned in portion of the end of the vessel. In this case we some-
times make the bridge piece the weakest part, so proportioned that it will bend,
or buckle instead of the central bolt stretching. It will be obvious that instead
of the opening in the end of the vessel being round, it could be elliptical, the
cap being also elliptical, so that it could be inside and the bridge piece or collar
outside. Also that the cap could be screwed into the end of the vessel without
the central bolt. That the cap and bolt could be one, so dispensing with one

page_text: flange of the cup or gas check. And that the screw valve instead of being formed
of the central bolt, could be separate.
Dated this 9th day of September 1898.
A. SWEETSER,
ANDREW PRINGLE.
Improvements in or relating to Compressed Gas Vessels.
"
I, ALFRED SWEETSER, of 10, St. Faith's Road, Tulse Hill, in the County of
London, formerly of 'Garwood," Rosendale Road, Herne Hill, Consulting
Mechanical Engineer, and ANDREW PRINGLE, of Cromwell House, Bexley Heath,
in the County of Kent, Gentleman, 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 vessels for containing compressed or liquefied gases,
and has for its chief objects an improved method of and means for closing the
end or ends of such vessels whereby ready access is afforded to the interior, and
the bursting of the vessels explosively by excessive pressure of gas is made
practically impossible. According to our invention the end or ends of the gas
vessel is, or are, closed by a cap or caps held in place by a rod which, when the
pressure of gas in the vessel becomes excessive, stretches and allows the cap or caps
to lift and so relieve the pressure. The invention includes improvements in detail
as hereinafter described with reference to the accompanying drawings, in which
Fig. 1 is a central longitudinal section of a gas vessel constructed with our
improved closing devices, and
Fig. 2 is a longitudinal section of another vessel illustrating a modification.
A is the tubular shell or body of the gas vessel, open at both ends. It may be
of uniform diameter throughout, but we prefer to reduce its diameter, as shown, at
each end, so as to diminish the area of, and consequently the pressure on, the
closing devices. The ends are closed by caps B, B which have a shoulder 1 resting
against the end of the body, and a reduced part 2 which fits loosely in the neck
of the vessel, which neck is preferably made slightly taper, the larger end being
outermost.
C is a central bolt extending the whole length of the vessel and passing through
the caps B, B and having nuts D, E screwed upon its ends whereby the caps are
held tightly and firmly in place. Leakage of gas between the caps and the neck
of the vessel, and between the caps and the bolt is effectively prevented by
annular rings F made of lead or other soft metal, or in some instances of gutta-
percha, or other suitable material. The said rings are formed with inner flanges 3
and outer flanges 4, the former to bear against the bolt, and the latter against
the neck of the vessel. They are threaded on the bolt and rest with their flat
sides against the inner faces of the caps B, thus forming gas checks, the pressure
of the gas in the vessel pressing the flanges 3 and 4 tightly against the bolt and
neck respectively, and preventing leakage. The sectional area of the bolt C is so
proportioned in respect to the area of the inner faces of the caps B that in the
case of excessive and dangerous pressure being from any cause generated in the
vessel, such pressure acting on the caps B will operate to stretch the bolt C in
excess of the stretch of the vessel, and so by raising the caps B will afford relief
without risk of explosion.
We sometimes utilize the bolt to form a part of the screw-valve for controlling
the delivery of the gas from the vessel. For this purpose we drill an axial hole G

page_text: of suitable length from one end of the bolt, and we provide it with a screw-thread
to take the spindle H which forms the valve. From the end of the hole G we
continue with a hole J of smaller diameter, which leads through the side of the
bolt and opens at 5 into the interior of the vessel. The corner 6 constitutes the
valve seat against which the tapered end of the spindle H bears when the spindle
is screwed in. K is a nut screwing on the end of the bolt and forming a gland
or stuffing-box in a well known manner as shown in the drawing, to prevent the
escape of gas past the spindle H. L is a boss to which the usual connection is
made for the delivery of the gas. The passage in the said boss communicates
with the hole G through an opening M in the side of the bolt. In some instances
we reverse the construction and arrange the valve H at right angles to the bolt
instead of axially therein, and take the gas out through the end of the bolt.
Our improved construction of closing devices allows of obtaining ready access
to the interior of the vessel.
As applied to gas vessels which are permanently closed at one end, as indicated
in Fig. 2, the bolt C is made to terminate in, or preferably screws into a bridge
piece N which is first passed through the neck of the vessel, and then turned to
bear against the internal shoulder n. In this case the relief is afforded by
the bending of the bridge N when the pressure of gas becomes excessive.
In
some instances the cap at one end is made integral with the bolt, in which case
the inner flange 3 of the corresponding gas check may be dispensed with.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. In a gas vessel furnished with a cap or caps for closing the end or ends,
a rod constructed and arranged to hold the cap or caps in place, and to stretch
when the pressure of gas in the vessel becomes excessive, substantially as, and
for the purpose, specified.
2. The method of closing a gas vessel by a loose fitting cap, and a gas check,
in combination with a central bolt which stretches under excessive pressure of
gas in the vessel, and allows the cap to lift, substantially as described, and for
the purpose specified.
3. The method of closing both ends of a gas vessel by means of loosely fitting
caps and gas checks, and a central bolt passing through said caps, and having
nuts on its ends to secure the caps, substantially as, and for the purpose, described.
4. The combination with the gas vessel, of the central bolt C constructed to
receive the valve spindle, the cap B, and the nut E formed with a boss adapted
to receive the connection for the delivery of the gas, substantially as described.
5. A gas vessel furnished with closing devices, substantially as described with
reference to Fig. 1 of the accompanying drawings.
6. The modified form of closing device substantially as described with reference
to Fig. 2 wherein the central bolt is attached to a bridge piece N bearing against
the internal shoulder of the vessel.
GEORGE HARRISON,
10, Staple Inn, London, W.C., Agent for the Applicants.