IMPROVEMENTS TO AID AND WATER DISCHARGE APPARATUS FOR STRAM PIDES
Year: 1857

page_text: LETTERS PATENT to George McCallan. of Johnstone. in the County of
Renfrew, North Britain, Gasfitter, for the Invention of "IMPROVEMENTS
TO AID AND WATER DISCHARGE APPARATUS FOR STRAM PIDES."
Scaled the 7th July 1857, and dated the 24th February 1857.
PROVISIONAL SPECIFICATION left by the said George M'Callan at the
Office of the Commissioners of Patents, with his Petition, on the 24th
February 1857.
I. GEORGE MCCALLAN, of Johnstone, in the County of Renfrew, North
Britain, Gasfitter, do hereby declare the nature of the said Invention for
IMPROVEMENTS IN AIR AND WATER DISCHARGE APPARATUS FOR STEAM PIPES," to
be as follows, that is to say:-
This Invention relates to a combined apparatus to be used for effecting the
discharge or blow-off of air and water as they accumulate in steam pipes and
connections of various kinds as used for heating and other purposes.
This apparatus consists of a small receiver, connected at its upper end with
the steam pipe to be cleared of air. This vessel has also a vertical pipe
attached to it outside by a short branch near its upper end: at the top of this
vertical pipe there is a small air valve, having a long tubular stem depending
from it. This stem is open at its lower end. which dips into a small quantity of
mercury contained in the pipe, whilst the upper end is closed. So long as cold
air flows into the receiver from the steam pipe above this air finds its-way
out through the outside air valve, but when steam begins to flow in, its heat
acting upon the air contained in the tubular stem of the air valve, causes the
Price 8d.1
"

page_text: valve to rise upwards and close the air escape. In this way. whilst any air
from the steam pipe flows easily away. no steam can ever be lost. The
bottom of the receiving vessel has in it a small water-discharge branch,
governed by an equilibrium valve, the top of which carries a ball float. Thus,
as water pours into the receiver from the steam pipe it gradually accumulates
until its level is high enough for it to float the ball. upon the equilibrium valve.
and discharge the water. When the water level subsides the sinking of the
ball float closes the valve.
With this apparatus steam pipes can be kept perfectly free from accumu
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George McCallan in the Great Seal Patent Office on the
24th August 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I. GEORGE
MCALLAN. of Johnstone, in the County of Renfrew. North Britain, Gasfitter,
send greeting.
WHEREAS Iler most. Excellent Majesty Queen Victoria. by ler Letters
Patent, bearing date the Twenty-fourth day of February, in the year of our
Lord One thousand eight hundred and fifty-seven, in the twentieth year of Her
reign. id. for Herself. Her heirs and successors. give and grant. unto me, the
said George McCallan. Her special license that 1. the said George McCallan,
my executors, administrators. and assigns. or such others as 1, the said George
M'Callan, my executors. administrators. or assigns, should at any time agree
with and no others, from time to time and at all times thereafter during
the term therein expressed. should and lawfully might make, use. exercise.
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
AIR AND WATER DISCHARGE APPARATUS FOR STEAM PIPES,". upon the condition
(amongst others) that I. the said George McCallan, by au instrument in writing
under my hand and seal. should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be per-
formed, and cause the saine to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that 1. the said George McCallan, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement in writing. reference being had to the accompanying Drawings. and
to the letters and figures marked thereon, that is to say: -
My said Invention relates to a combined apparatus to be used for effecting
the discharge or blow-off of air and water as they accumulate in steam pipes
and connections of various kinds as used for heating and other purposes.
This apparatus consists of a small receiver, connected at its upper end with
the steam pipe to be cleared of air. This vessel has also a vertical pipe
attached to it outside by a short branch near its upper end: at the top of this
vertical pipe there is a small air valve. having a long tubular stem depending
from it. This stem is open at its lower end. which dips into a small quantity of
mercury contained in the pipe, whilst the upper end is closed. So long as cold
air flows into the receiver from the steam pipe above this air finds its way out
through the outside air valve. but when steam begins to flow in, its heat
acting upon the air contained in the tubular stem of the air valve, causes the
valve to rise upwards and close the air escape. In this way whilst any air
from the steam pipe flows casily away no steam can ever be lost. The bottom
of the receiving vessel has in it a small water-discharge branch, governed by
an equilibrium valve, the top of which carries a ball float. Thus, as water
pours into the receiver from the steam pipe it gradually accumulates until its
level is high enough for it to float the ball, open the equilibrium valve, and
discharge the water. When the water level subsides the sinking of the ball
float closes the valve.
With this apparatus steam pipes can be kept perfectly free from accumu-
lations of air and water without any loss of valuable steam.
And in order that my said Invention may be properly understood I will
now proceed to describe the several illustrative Figures on the explanatory
Sheet of Drawings. which I have hereunto appended for the purpose of
showing certain modifications under which my improvements may be judi-
ciously carried out in practice.
Figure on my Sheet of Drawings is an elevation of one modification of
my improved apparatus for discharging air and water from steam pipes,
cylinders, or other vessels which it is desired to free from air or water:
Figure 2 is a vertical section of the same; Figure 3 is a plan of the arrange-
ment; and Figure 4 a transverse section, corresponding thereto. Figure 5 is
a vertical section of an air and water discharger. somewhat modified from the
arrangement shown in Figures 1 to 4.
The apparatus consists essentially of a metallic vessel, the interior of which
forms a chamber or receiver through which the air and water of condensation

page_text: now. The receiver A is made by preference of cast iron, and formed in two
parts, which are bolted together at the central flanges. The receiver is of an
oblong cylindrical shape with hemispherical ends: a laterally projecting part
on the upper portion of the casting forms a chamber B for the air-discharging
valve. The lower part of the receiver A terminates in a pipe C, which serves
to carry off the water of condensation. The upper part of the receiver is
connected by means of the pipe D with the steam pipe E or other vessel. The
air which passes through the air chamber B is carried away by means of the
pipe F. Inside the receiver A a metal float G is arranged. In this modifica-
tion the float is of an oblong spheroidal shape, and it has an open tubular
passage through it. The tube II, forming the upper part of this cylindrical
passage, is soldered or brazed to the float G; to the lower extremity of this
tube H is attached a double-seated valve 1, which governs the outlet apertures
J in the pipe K. On the upper extremity of the eduction pipe K is a trian-
gular feather or guide I, which serves to keep the float G perpendicular.
The valve I rests upon the double seatings formed upon the upper part of the
eduction pipe K, and in this position the communication between the chamber
of the receiver A and the pipe K is closed. The lower extremity of the pipe
K enters the water pipe C, which is attached to the end of the pipe K by
means of a screw or other suitable connection. The smaller chamber B,
formed at the side' of the receiver A, is furnished with a valve, having a tubular
stem M; the seating of the valve is formed in the elbow piece of the air pipe
F. The tube of the valve M is open at its lower extremity, which rests in
some mercury placed in the lower part of the chamber B. The upper end of
the valve M is guided by the cylindrical part of the lower portion of the pipe
F, and its perpendicular position is partly maintained by means of the feathers
or guides N, made upon the tubular part of the valve just below the face. A
milled-headed screw O is fitted in the upper part of the elbow piece of the pipe
F; through this opening fresh mercury may be poured into the chamber B
when required.
"
When the apparatus is attached to a steam pipe, as shown in Figure 1 of
my illustrative Drawing, the cold air passes from the steam pipe E down the
egress pipe D and into the receiver A, and thence into the chamber B; the
quantity of mercury in the chamber B is so proportioned to the weight of
the valve M, that whilst cold air is flowing into the chamber. the passage
through the air pipe F remains open, and the air passes off unimpeded; but
when steam flows into the chamber B, the air within the tubular stem of the
valve M is immediately elevated in temperature. and its volume consequently
expanded. This expansive force causes the valve to rise, and thereby close the

page_text: passage in the pipe F. and thus prevent the loss of steam. The water of con-
densation as it flows down the steam pipe collects at the lower part of the
chamber A. and when a quantity has accumulated sufficient to lift the float G."
the water flows away through the apertures J in the pipe K. and thence away
into the pipe C. which may be connected with a suitable reservoir. The tube
II of the float G is open at the upper part, so as to admit the steam to the
upper part of the pipe K and maintain the equilibrium. Any water that may
accumulate within the float is discharged through small apertures made in the
valve I and flows through the apertures J. when the float G is raised by the
uplifting force of the accumulated water of condensation. This mode of
arranging the float has been contrived for the purpose of counteracting a dif-
ficulty that is found to arise in the practical use of ball floats. When these
floats are in constant use it is found that water will make its way into
the interior of the ball, and this water by increasing the weight of the
float consequently impairs its efficiency. and prevents the valve from acting
with that degree of nicety so essential in a self-acting apparatus of this kind.
By making holes through the valve I. any water that may find its way into
the ball float escapes when the valve is raised, and this arrangement is found
io obviate the difficulty and prevent the inconvenience referred 10.
In the modification of my improved air and water discharger, shown in
Figure 5 of my Sheet of Drawings. the ball float G is of the ordinary globular
form, but it is not provided in this instance with a central vertical tube. The
hall float G and the double-seated equilibrium valve I is lifted by the water
of condensation when a sufficient quantity has accumulated in the chamber A
of the receiver to overcome the gravity of the float and valve. When the valve
His lifted. the water flows through the apertures J in the pipe K and away
by the water pipe C to a reservoir or suitable receiver connected therewith.
The arrangement of the air chamber B and the tubular valve M corresponds
to that shown in Figure 2 of my illustrative Drawings. and the action of this
part of the apparatus is in all respects the same as that herein-before
described.
In the modification of my improvements. shown in Figures 1 to 4 of my
Sheet of Drawings. the air discharger is cast in one piece with the upper part
of the receiver A. but in the modification shown in Figure 5 this is not the
case. The air-discharging chamber B is cast separately. and connected by
means of a screw to the receiver A. This arrangement of the apparatus is
found convenient in practice. as it admits of either part being used separately,
because in some instances the appliance of the air discharger alone to steam
pipes would be all that is necessary.

page_text: In the modifications of my apparatus, shown in Figures 2 and 5 of my Sheet
of Drawings. the lower half of the receiver A is cast to form a hollow base, upon
which the apparatus stands, a hole is made in one part of this base to allow of
the pipe C passing through it; but in the arrangement shown in Figure 1 of
my Drawings the lower part of the receiver A is cast without a base. the
attachment of the pipe C and D serving to support the apparatus.
By means of the foregoing mechanical appliances steam pipes. cylinders, or
other vessels may be kept at all times clear of water or air without requiring
the slightest attention on the part of the engineer or attendants, and withou
involving any loss of steam.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I may observe, in conclusion, that. I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of my Invention; but what I
consider to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Palent. is.-
First, the general arrangement and construction of apparatus for freeing
steam pipes, cylinders. or other vessels of air and water of condensation, as
herein-before described
Second, the arrangement and construction of equilibrium float valves. having
a tubular passage through the float and with holes made through the valve.
for the purpose of preventing the accumulation of water therem, as herein-
before described.
Third, the use and application of self-acting apparatus for discharging air
from steam pipes, cylinders, or other vessels, and preventing the egress of
steam, as herein-before described.
Fourth, the system or mode of preventing the egress of steam from pipes
and other receptacles by the expansive action of air or mercury.
In witness whereof. I. the said George McCallan, have hereunto set my
hand and seal. this Twenty-first day of August, One thousand eight
hundred and fifty-seven.
GEORGE MCCALLAN. (L.S.)