An Automatic Quick Acting Steam Valve for Steam Boilers.
Year: 1898

page_text: Date of Application, 22nd Nov., 1898-Accepted, 14th Jan., 1899
COMPLETE SPECIFICATION.
An Automatic Quick Acting Steam Valve for Steam Boilers.
We, JOHN HUTCHESON, Engineer, of 289, High Street, and JAMES FRENCH
SERVICE, Engineer, of 5, Annfield. Place, Dennistoun, both in the County of
the City of Glasgow, do hereby declare the nature of our invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:―
Our invention comprises a steam valve for fitting on boilers for the purpose
of automatically shutting off the steam supply should a burst take place in
the main steam pipes; and also in event of a boiler tube bursting, in the case
where a number of boilers are supplying steam through one main steam pipe,
for preventing the steam blowing from the said number of boilers into the
boiler in which the tube has burst, by automatically closing a valve.
And in order that our said invention and the manner of carrying same into
practice may be properly understood we have hereunto appended one sheet of
explanatory drawings, in which Figures 1 and 2 represent two sectional views
of this valve, and Figure 3 a similar view but with a single balanced piston.
The flange A is connected direct to the boiler, and the flange B connects to the
main steam pipe.
The improved construction of valve consists as follows:-A steam chest a is
formed and within it is fitted a cylinder b fitted with a single piston 6 as shown
in Figure 3, or the cylinder may be made up in two parts of larger and smaller
diameters b and c as shown in Figure 2, in which are fitted pistons formed
in one piece. The piston at one end has a hollow rod connection 1) to the
valve G on the branch B which is coupled to the main steam pipe, while the
other end of piston has a rod connection d fitted with a recoil spring N within
a cylinder N¹. A shut down screw actuated spindle K, fitted with a stop valve H
is placed within the chest a; while a steam regulating valve L is fitted in con-
nection with the main steam pipe. The valve L is for admitting a jet of live
steam to main steam pipe through the branch M so as to warm the pipes
gradually before opening the main valves. The pipe F communicates direct
with boiler for admitting steam to cylinder through the port E, while the pipe M
communicates with the branch B.
Should a burst take place in the main steam pipe or the engines race in con-
sequence of the propellor rising out of the water the pressure in the said steam
pipe will fall and at same time will fall in the small cylinder 6 which com-
municates with the main steam pipe through passage D. The full pressure is
retained in cylinder c by means of a pipe F communicating direct with the boiler
connection A and this pressure in cylinder c acting on the piston closes the
valve G, being connected to same.
Again should a burst take place in a tube or other part of the boiler to which
the valve is connected at A, the pressure at A will fall and the rush of the steam
acting on the back of the valve H will close same, as it is loose on the spindle K

page_text: and not attached to same, or we may apply the same arrangement to this valve H
as herein before described for closing the valve G.
The small valve L is used for admitting steam slowly to main steam pipe so as
not to heat it too quickly, and the valve G will not open until the pressure in main
steam pipe is almost equal to pressure in boiler.
The spring N is for the purpose of adjustment.
Having now particularly described and ascertained the nature of our said in-
vention, and in what manner the same is to be performed we declare that what
we claim is ;-
First. In valves for steam boilers the combination of cylinder or cylinders
with piston or pistons working therein, and passage D and pipe F substantially
as and for the purposes set forth.
Second. In valves for steam boilers, the arrangement in combination of piston
or pistons and cylinder or cylinders with their auxiliary fittings, substantially
as and for the purposes set forth.
Dated the 21st day of November 1898.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.!