IMPROVE- MENTS IN THE CONSTRUCTION OF STEAM AND WATER TRAPS, AND IN THE FLOATS AND VALVES FOR THE SAME, ALSO TO SOME EXTENT APPLICABLE TO OTHER FLUID REGULATING VESSELS FOR CONTROLLING THE FLOW OF THE FLUIDS PASSING THROUGH THEм
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by David Allan Graham at the Office of
the Commissioners of Patents, with his Petition, on the 20th December
1866.
I, DAVID ALLAN GRAHAM; of the City and County, of Perth, North Britain,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE CONSTRUCTION OF STEAM AND WATER TRAPS, AND IN THE FLOATS AND
VALVES FOR THE SAME, ALSO TO SOME EXTENT APPLICABLE TO OTHER FLUID REGULATING
VESSELS FOR CONTROLLING THE FLOW OF THE FLUIDS PASSING THROUGH THEм," to be
as follows, that is to say:
This said Invention consists mainly in a new or improved form or construction
of "trap" or vessel and its parts, or float valve and fittings for allowing and
regulating the discharge or escape of the condensed steam or other water
which collects and gravitates to the lower parts of steam pipes, steam cylinders,
and other similar conduits and vessels without loss of steam, and at or
under whatever regular or varying pressure the steam may be at contained
in such pipes or vessels, and which new or improved "trap" or vessel as a
whole is more simple, efficient, and economical in its construction and action
than such vessels have been as heretofore constructed. The shell or outer caso
of the "trap" may be of various shapes to suit convenience or taste, but it
is preferred either to be of a hollow spherical form cast in two parts and
jointed together by turned flanges and screw bolts at the centre, or to be of
a cylindrical form vertically with a hollow semi-spherical bottom, and an.
annular flange joint and disc cover at the top, in either case the vessel being
only slightly larger inside than the hollow spherical copper float for opening

page_text: and closing the outlet valve, the seat of which valve is turned cylindrically
and tightly jointed and fitted into a socket formed on the centre of the lower
half or sphere of the outer case. Directly over the vertical centre line of
this outlet valve seat a small annular piston seat is tightly fitted into a socket
formed on the upper half of the spherical outer case or in the disc cover
when so constructed.
The hollow spherical float has a. vertical tube passing right through its
vertical axis coinciding with the axes of the valve and piston seats, and the
line. of motion of the float in rising and falling to open and shut the valve,
the lid or cover of which is attached to the lower part of the float and to the
tube passing through it, which projecting part of the tube forms the stem of
the valve and works through a hole for the purpose in the bridge of the valve
seat, while the small hollow piston which is made of the same diameter and
area as the outlet orifice of the escape valve is attached to the upper part of
the float, and a portion of the tube projecting through it for the purpose so
as to work truly and steam-tight in its seat, and form a counterbalance
pressure surface tending to lift or open the valve equivalent to that acting
on the upper surface of the lid or cover of the valve tending to close it,
whatever the pressure of the steam may be in the outer shell or vessel, and
which presses equally in all directions round the hollow spherical float, while
the pressure of the air without, which acts on the lower side or surface of the
outlet valve lid, is counterbalanced by the pressure of the air acting up through
the open-ended tube (passing through the float) upon the upper end or area
of the piston by a small space formed above it, where a screw plug is fitted into
the socket from the outside so as to regulate the height to which the valve
shall rise off its seat in proportion to the quantity of water required to be
discharged from the outer case.
The action of this improved trap is as follows:-The outer shell or vessel
is bolted by a lateral or side flange cast on it for the purpose to any
convenient wall or other equivalent at a lower level than the pipes or vessels
from which the water is to be discharged, and from which a pipe or branch
is led into the upper part of the vessel, so that the water will flow into it
and float up or raise the float which opens the valve and allows the water to
flow out through it until the float sinks with the water as it decreases, in the
vessel so as to shut the valve, and as the water again increases below and
around the hollow ball or float it again raises the valve and allows the
surplus water above a fixed regulated level to escape, and so on so long as
the water flows or is led into the trap or vessel from the pipes or vessels required
to be emptied or drained of such water.

page_text: As this improved arrangement of discharge valve is made quite on a balance
or equilibrium principle very little power is required to actuate it, so that a
float of the small size and buoyancy necessary to raise its own weight and that
of the valve and piston, and overcome the slight friction of their action and
have sufficient weight and force by its surface hold of the water as to thoroughly
close the valve in its downward action is all that is required, and as a con-
sequence the trap or vessel itself is also reduced under these improvements to
the least possible practical size in proportion to the size of the valve and quantity
of liquid required to be discharged in any particular case, which are two
important economical advantages in the first cost and labour of producing
such traps, while the simplicity of construction and action of the few parts in
this new arrangement of equilibrium float valve renders it most durable and
free from the chance of stoppage or derangement in its action.
Where very
high-pressure steam is used in the pipes or vessels water is sometimes forced
through the small pores or openings in the copper or joints of such hollow:
floats so as to partially fill them with water and destroy their buoyancy and
action to allow of the escape of any such water, an air hole is passed through
the open ended tube into the upper part of the float or some little distance
from the bottom of the float which serves the double purpose of admitting air
into it so as to prevent a vacuum being formed within the float, and also to
allow any such water which may collect in it to escape or gravitate down
through another hole formed through the tube at the lower part of the float
for that purpose. A small safety air valve opening inwards is fitted in the
upper part of the outer vessel to allow of the escape of all air from the
interior at any time when desired by pressing it in from without, and also to
admit air by its own action when the pressure of the steam within the vessel is
reduced by condensation below that of the atmosphere outside so as to prevent
a vacuum being formed within the vessel and pipes or vessels directly connected
with it. An open ended pipe is by preference attached to the faucet or socket
below the outlet valve to carry the discharged water away to any desired place,
and yet admit air up through it and the hollow tube passing through the
float to the upper surface above the balance pressure piston and to the interior
of the float. Instead of a piston at the top of the hollow stem or tube passing
through the float, a disc or cup of india-rubber may also be used for equalising
or balancing the pressure in the interior of the vessel acting upon the upper
surface of the lid of the escape. valve, and the buoyancy of the floats may be
regulated by raising or lowering the position of the air and water holes
passing through the open tube into the floats so as to contain a certain
regulated portion of water at the lower part of the floats.

page_text: Instead of a hollow copper sphere being used as the float other forms of
hollow or solid floats may be employed constructed of other metals or other
materials, and when made heavier in specific gravity than water they may be
counterbalanced, by passing a rod up. from them, through the balance or
equilibrium pistons by attaching the upper end of the rod to a counterbalance
lever fulcrumed on a stem or standard on the cover or upper part of the
vessel, the lever being fitted with a-balance weight.---
Although this improved trap has only been described as used for carrying
off water from steam pipes or vessels it will be obvious that it is also applicable
for the discharging of water and other liquids from pipes and vessels containing
other vapours and gases than steam at various pressures (particularly at
pressures above that of the atmosphere) from which it is desired to draw off
such liquids..
A modification of this float valve arrangement (herein-before described
as forming one feature or. part of these improvements) may also be applied
to.regulate the ingress of the egress, or both, of the water through these valves
in open water cisterns (such as are used for the supply of water to houses and
public works generally), so as to retain the water in them at a nearly uniform
level. When so applied the lower stem of the open tube is made long
enough to reach down to and actuate the lid or cover of the inlet or the
outlet valve direct which is attached to it, so as to open or shut the valve
upon the seat which is fitted at or near the bottom of the cistern, and when
so made to work an inlet valve the valve is made to open into the inlet
branch pipe against the pressure of water therein, so that the rising of the
float and pressure of the water in the pipe upon the valve lid shuts it as the
water rises to its proper level in the cistern, and vice versa, the falling of the
water. and float opens the valve, whilst the valve is made equilibrium in its
action, in this case by the same pressure of water which acts on the valve
in the pipes passing up through the open tube so as to act on the top surface
of the reacting or balance piston. When the water and float rises to the
proper fixed level, or above it, a rod from the top of the float may be made
to open a cock.or valve direct or through an intermediate lever for. the
purpose, so as to allow of the discharge or escape of all surplus water through
the cock or valve collected in the cistern above the proper level, or otherwise
a simple overflow pipe may be used to carry off. all water from the cistern
above the said level.
•
An arrangement of this equilibrium float valve may also be constructed
for regulating and carrying off the discharge water from the bottom of
reservoirs and waterworks through a valve chest in direct connection with

page_text: the main supply pipes for conveying the water for use, by a rod projecting
up from the valve either worked by a screw or lever arrangement by haud
above the valve chest, and in some cases above the level of the water, or
automatically by the rod. being attached to a float upon the surface of the
water, the equilibrium action of the valve being arranged within the chest or
trap directly attached to the main pipes for carrying off the water, the valve
lid working on a seat placed in a division in the chest separating the inlet
from the outlet orifice, and attached by a short stem (which may be either
hollow or not as desired according as the pressure is equalised on the top of
the piston and bottom of the valve direct through the stem or otherwise) to
a piston working in a short inverted seat or cylinder formed in the cover of
the chest, or instead of the piston a second valve lid may be attached to the
stem and the two valves made to work as a "double beat" valve, on two seats
formed or inserted in two divisions in the chest opening at top and bottom
into a double branch orifice in the chest leading into an outlet or inlet branch,
and the rod for actuating either of these arrangements of equilibrium valves
for stopping off or regulating the discharge water or gas through main pipes
is passed out through a stuffing box in the cover of the chest, and when the
valve is workedy hand, as a "stop off" or a sluice valve, the rod may be
screwed and made to work down through a nut into the stem of the valve or
in.the cover of the chest as desired.
In the arrangement with the piston upon the stem above the valve it
may be made longer in area than the valve and fitted with a spiral spring above
it of a regulated pressure, so that when the pressure of the water, gas, or other
fluid upon the extra area of the piston above that of the valve becomes greater
than that due to the spring the valve would open and allow the fluid to escape
through the valve from the inlet to the outlet passage, when the pressure
reached the fixed required and regulated pressure within the pipes or vessels
connected therewith containing the fluid so as to form a "reducing pressure
valve."