Improvements in and connected with Plug Taps and Valves.
Year: 1899

page_text: Date of Application, 12th Sept., 1899-Accepted, 28th Oct., 1899
COMPLETE SPECIFICATION.
Improvements in and connected with Plug Taps and Valves.
I, FRANK MERWIN ASHLEY, of 97, Liberty Street, in the City, County, and
State of New York, United States of America, Mechanical Engineer, do hereby
declare the nature of this invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to valves for fluid passages, the object being to provide
a construction which will prevent leakage of the valve when it is in its normal
state, and by means of which any sticking of the valve when it is operated may be
easily and simply overcome.
The invention relates more particularly to what are known as plug valves in
which a conical plug is rotated upon its axis in a correspondingly shaped cham-
ber. It is well known that such a valve, when forced downward into its seat will
effectually prevent leakage around its side, but that at the same time it is liable
to stick or become locked in its seat by the friction of the contact surfaces, and
rotary motion cannot be imparted to the plug without prior longitudinal displace-
ment and release. It has been proposed to operate these valves by means of a
threaded stem the effect of which is that the plug is simultaneously moved around
and in the direction of its axis, but in operating such devices joints are commonly
opened through which the fluid escapes. My improved valve can be moved longi-
tudinally and then rotated without permitting the escape of fluid.
I will describe my invention with reference to the accompanying drawings, in
which:-
-
Figure 1 shews a section of one form of my improved valve, parts thereof being
shewn as broken away.
Figures 2, 3 and 4, represent modifications of the construction.
The valve casing A, which is part of the fluid passage, is provided with the
usual conical seat for the plug valve B. The casing has an annular flange a
surrounding the head of the valve and externally threaded to receive the cap
nut a¹. Upon the top of the flange rests a fixed collar a³, which is clamped in
place by the cap-nut a. The collar is provided with a comparatively large cen-
tral opening a³. At the top of the plug valve there is a circular projection b, which
passes up into the opening in the collar a² as shewn, and in the centre of this
projection, the valve stem rises. Around the base of the valve stem there is
located a packing ring c upon which rests a sleeve c¹, which, as shewn by Figure 1,
is confined by another sleeve d threaded upon the stationary collar a² and pro-
vided with a handle or other means for rotating it. The upper end of the
sleeve abuts against the hand-wheel or cross-head 63, on the valve stem. It will
be observed that by rotating the sleeve d, the plug may be moved vertically in
either direction, and that, in whichever direction it may be moved, the packing c
always remains compressed, thus preventing leakage. In Figures 2 and 3, the
sleeve is shewn to be threaded directly into the collar a2 and fitted with a
wrench or handle whereby it may be turned. In Figure 2, the upper end of
the sleeve abuts against the locked nuts e upon the valve stem, whilst in Figure 4,
го

page_text: it abuts directly against the handle fixed upon the upper end of the valve stem.
In either construction, the valve itself may be moved axially by turning the
handle d'. In the construction illustrated by Figure 4, a certain pressure, may be
put upon the packing c by means of the nuts e¹, and this pressure may be main-
tained regardless of the pressure of the part d on the nuts.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. In a plug valve, the combination of the plug provided with a central cylin-
drical projection, a fixed collar provided with an opening into which the said
projection fits, a valve stem projecting from the cylindrical projection through
the opening in the collar and provided with means for turning it, a sleeve sur-
rounding the valve stem projecting into the opening in the collar and confining
a packing ring between itself and the cylindrical projection, a second sleeve
threaded with the collar and abutting against the first sleeve and the device for
turning the valve stem respectively, and means for rotating the second sleeve,
substantially as herein before described and as illustrated by the accompanying
drawings.
2. In a plug valve, the combination of the plug provided with a central cylin-
drical projection, a fixed collar provided with an opening into which the said
projection fits, a valve stem projecting from the cylindrical projection through
the opening in the collar and provided with means for turning it, a. sleeve sur-
rounding the stem and confining a packing ring between itself and the cylindrical
projection, and means for raising and lowering the plug, substantially as described
and as illustrated by the accompanying drawings.
3. In a plug valve, the combination of a plug provided with a central cylin-
drical projection, a fixed collar provided with an opening into which the said
projection fits, a valve stem rising from the cylindrical projection through the
opening in the collar and provided with means for turning it, a sleeve surrounding
the stem and confining a packing ring between itself and the cylindrical projec-
tion, means for maintaining a constant pressure on the packing ring, and means
for raising and lowering the plug, substantially as hereinbefore described and as
illustrated by the accompanying drawings.
Dated this 11th day of Santambor AD 1800.