IMPROVEMENTS IN FEED APPARATUS FOR STEAM BOILERS
Year: 1879

page_text: LETTERS PATENT to Archibald Thomson, of Southampton, in the County of
Southampton, Engineer, for the Invention of "IMPROVEMENTS IN FEED
APPARATUS FOR STEAM BOILERS."
Sealed the 12th August 1879, and dated the 4th March 1879.
PROVISIONAL SPECIFICATION left by the said Archibald Thomson at the
Office of the Commissioners of Patents on the 4th March 1879.
ARCHIBALD THOMSON, of Southampton, in the County of Southampton,
Engineer. IMPROVEMENTS IN FEED APPARATUS FOR STEAM BOJLERS."
"
This Invention has for its object the constructing or fitting of the feed apparatus
of steam boilers with simple and easily controlled parts for removing air or gas
from the feed water in order to prevent corrosive action, believed to be due to air
or gas accompanying the feed water into the boilers.
The Invention consists in connecting the pipe or pipes from the feed pump or
pumps to one or more air separating vessels from which the feed water is led
onwards to the boiler or boilers by one or more pipes. In the case of each vessel
both the inlet and outlet feed pipes are connected to the lower part, whilst an outlet
for air is connected to the tap. The vessel is fitted with a glass gauge or with trial
A cock or valve which can be
cocks for ascertaining the level of the water inside.
adjusted by hand is fitted on the air discharge pipe, and when the apparatus is in
action this cock is adjusted so as to allow just so much air or gas to continuously
escape as will cause the level of the water in the vessel to be maintained at about
the middle of the glass gauge, or at the desired level. Instead of adjusting the
discharge of air or gas by hand the apparatus may be fitted with simple automatic
apparatus consisting of a float inside the vessel connected to a valve fitted to the air:
outlet, this valve closing when the float rises. If the air or gas passes off too
quickly the water will rise in the vessel and carry up the float so as to close or
partly close the valve, and vice versd. The rod of the float may be continued out
through a stuffing box to be connected to a hand lever, or to a weighted lever or
spring which can be adjusted to regulate the action of the float.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Archibald Thomson in the Great Seal Patent Office on the 22nd
August 1879.
ARCHIBALD THOMSON, of Southampton, in the County of Southampton,
Engineer. IMPROVEMENTS IN FEED APPARATUS FOR STEAM BOILERS."
"
My said Invention has for its object the constructing or fitting of the feed
apparatus of steam boilers with simple and easily controlled parts for removing air
or gas from the feed water in order to prevent corrosive action, believed to be due
in many cases to air or gas accompanying the feed water into the boilers. The
application of my improved apparatus has also the important advantage of increasing
the steam producing power of the boilers in consequence of its preventing the air
from entering the boilers along with the feed water, whilst the absence of air from
the steam allows an improved vacuum to be obtained in the condenser and thus
increases the power developed by the engines which are in connection with the
boilers.
My Invention consists in connecting the pipe or pipes from the feed pump
or pumps to one or more air separating vessels, from which vessels the feed water is
led onwards to the boiler or boilers by one or more pipes. In the case of each vessel
both the inlet and outlet feed pipes are connected to the lower part, whilst an
outlet for air is connected to the top. The vessel may be fitted with a glass gauge
or with trial cocks for ascertaining the level of the water inside. A cock or valve
which can be adjusted by hand is fitted on the air discharge pipe, and when the
apparatus is in action this cock is adjusted so as to allow just as much air or gas to
continuously escape as will cause the level of the water in the vessel to be main-
tained at about the middle of the glass gauge or at the desired level. Instead of
adjusting the discharge of air or gas by hand the apparatus may be fitted with
simple automatic apparatus consisting of a float inside the vessel connected to a
valve fitted to the air outlet, this valve closing when the float rises. If the air or
gas passes off too quickly the water will rise in the vessel and carry up the float so
as to close or partly close the valve, and vice vered. The rod of the float may be
continued out through a stuffing box, to be connected to a hand lever or to a
weighted lever or spring which can be adjusted to regulate the action of the float.
In some cases the apparatus is fitted with a pipe and stopcock for admitting a jet
of steam amongst the water entering from the pump or pumps for the purpose of
facilitating the separation of the air or gas.
And in order that my said Invention, and the manner of performing the same
may be properly understood, I hereunto append two Sheets of explanatory
Drawings, to be hereinafter referred to, and representing two modifications of
apparatus for carrying out my Invention. In these Drawings the same reference
numerals are used to mark the same or like parts wherever they are repeated.
Figures 1 and 2 on Sheet 1 of the accompanying Drawings are vertical sections
as at right angles to each other of one modification of my air extractor for steam-
boiler feeding apparatus; Figure 3 is a horizontal section near the air outlet; and
Figure 4 is a plan of the float. The air extractor consists mainly of a vertical
cylindrical vessel 1 fitted with an inlet pipe 2 at the bottom for the entrance of the
feed water from the pump or pumps, and formed with flanged outlets 3 near the
bottom for the connection of pipes to lead the feed water onwards to the boiler or
boilers. A short length of pipe 4 is fixed inside in continuation of the inlet 2 to
lead the inflowing water up past the outlets 3 so that it may go to the surface
before getting away by the outlets 3. A float 5, shown as made of metal and hollow,
but which may be of any other suitable material and construction, is attached to a
rod 6 having at or near its upper end a small slide valve 7 fitted to slide over a
narrow vertical port 8 in an air-outlet piece 9 which has connected to it an air
discharge pipe 10 fitted with a stopcock 11. The apparatus is shown empty and

page_text: with the float 5 resting down on the inlet tube 4, but when in action the feed water
pumped in lifts the float more or less, according to the proportion of air disengaged,
and closes the air-outlet valve 7 to a corresponding extent. The rod is continued
through a stuffing box and connected to a handlever 12, by means of which it can
at any time be ascertained if the parts are in working order. The float 5 is, as
represented in Figure 4, made with indentations on its sides to allow the air to pass
to the space above it.
Figure 5 on Sheet 2 of the accompanying Drawings is a vertical section of
another modification of my air extractor. In this example the float rod 6 is not
connected to an internal air-outlet valve, but being continued through a stuffing
box in the top of the vessel 1 is externally connected to a lever 13 which is to be
furnished with suitable counter weights, and which is connected by a link 14 to
the lever 15 of a stopcock 16 on an air-discharge pipe 10 connected to the top of
the vessel. This example is also shown as constructed for the introduction of a jet
of steam to facilitate the separation of air or gas from the feed water. The steam
pipe 17 fitted with a stopcock is inserted into the feed-water inlet pipe 2 so as to
direct the jet of steam up the centre of the vessel 1, and inside the vessel there is
fixed a cone 18 into the smaller bottom end of which the feed water enters from
the pipe 2. The cone 18 is fitted with a convex cover 19 which is perforated with
holes, and which insures the thorough intermingling of the jet of steam with the
water, both water and steam having to pass through the holes. Bars 20 are fixed
to the sides of the vessel 1 to guide the float 5, and by stop projections at their
lower ends determine it lowest position at some little distance above the perforated
top 19 of the cone 18.
Having thus particularly described my said Invention, and the manner of per-
forming the same, I have to state that I do not restrict myself to the precise
details herein described or delineated, but that what I believe to be novel and
original, and claim as the Invention secured to me by and in terms of the herein-
before in part recited Letters Patent is,―
1. The combination with ordinary steam-boiler feed pumps of a vessel or vessels
for separating air or gas, and applied between the pumps and the boiler or boilers,
such vessels having inlets and outlets for the water at or near the bottom and an
outlet for air or gas at the top, substantially as hereinbefore described.
2. The arranging or combining of the parts of air extractors for steam-boiler feed
apparatus, substantially as herein before described with reference to Figures 1 to 4
of the accompanying Drawings.
3. The arranging or combining of the parts of air extractors for steam-boiler feed
apparatus, substantially as hereinbefore described with reference to Figure 5 of the
accompanying Drawings.
4. The mode of and arrangement of parts for introducing steam into the air
extractor, herein before described with reference to Figure 5 of the accompanying
Drawings.
In witness whereof, I, the said Archibald Thomson, have hereunto set my hand
and seal, this Twenty first day of August, in the year of our Lord One
dad an
ARCH³. THOMSON. (LS.)