IMPROVEMENTS IN GAUGES FOR STEAM BOILERS AND IN THE CONSTRUCTION AND APPLICATION OF TAPS, COCKS, OR VALVES FOR OR TO SUCH GAUGES
Year: 1867

page_text: PROVISIONAL SPECIFICATION left by John Steven at the Office of the
Commissioners of Patents, with his Petition, on the 11th May 1867.
I, JOHN STEVEN, of the Firm of Steven and Struthers; of the City of
Glasgow, in the County of Lanark, North Britain, Bell and Brass Founders,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
GAUGES FOR STEAM BOILERS AND IN THE CONSTRUCTION AND APPLICATION OF TAPS,
COCKS, OR VALVES FOR OR TO SUCH GAUGES," to be as follows, that is to say :-
My said Invention has reference to the improved construction and application
or adaptation of certain taps or valves for glass tubed gauges of steam boilers,
and also in. the ducts or passages leading to and from the said valves, which
improvements render such gauges ör "gauge cocks" more durable and
less liable to derangement and leakage than they have been as heretofore
constructed.
These improvements consist essentially in forming a hollow annular conical
valve seat on the outer end of the upper and lower ducts or passages leading
straight or direct into the steam and water spaces of the boiler, each fitted
with a corresponding conical-pointed screw, hand plug, or spindle working
steam-tight on the said seat, and through a screw and packing gland fitted on
the front part of the hollow chamber of the metallic socket pieces carrying
the
upper and lower ends of the glass tube of the gauge; and further, in the
use of two ducts, passages, or channels closed at one end formed in the
"blow-off" nozzle; the one leading into the small chamber at the lower end
of the glass tube, or in direct communication with the interior of the tube,

page_text: and the other leading out through the "blow-off" nozzle or "nose cock," with
or having a small division or thickness of metal between them, through which
a lateral orifice is formed, leading from the former into the latter duct, having
fitted or applied thereto a conical seat and pointed screw tap or valve with
screw and stuffing gland, controlled at pleasure by a handle outside (as
described in reference to the outlet steam and water valves), so as to allow the
water in clearing out or "blowing through "the gauge to escape down the
first duct and out through the lateral opening controlled by the valve plug, and
off by the outlet passage open to the air at the "blow-off" nozzle, so that when
the steam, water, and "blow-off" valves are shut, or not required for the
-time-being, the valve surfaces are not exposed to the pressure or action of the
steam or water, while the narrow annular surfaces really necessary in this
construction of taps or valves and their extreme simplicity render the whole
instrument most durable and with little or no liability to leakage or derange-
ment in its action. The inner passage leading to the lateral orifice and escape
valve of the "nose cock" is pierced right through to the outside, and closed
up at the outer end by a small screw plug fitted thereto for removal, to allow
of the occasional insertion, when required, of a small rod or wire to clear out
any deposit which might lodge in the inner passage. The steam or water
ducts or channels at the top or bottom valves of the gauge are either cleared
out by the removal of the valve plugs and the insertion of a small rod, or
otherwise a small hole may be bored right through the axis of the valve
spindles for the like purpose, each furnished with a small screw plug which
might be made to fix the handle of the valve as well as to make the orifice
steam and water tight. Although the surfaces forming the steam and water
tight faces of the valves have been described as conical, they may when
preferred be made with flat or curved annular surfaces.