provements in Apparatus for Promoting the Circulation of Water in Steam Generators and Boilers, and Collecting the Solid Matter in same, and for Preventing the Formation of cale.
Year: 1897

page_text: PROVISIONAL SPECIFICATION
Improvements in Apparatus for Promoting the Circulation of Water
in Steam Generators and Boilers, and Collecting the Solid Matter
in same, and for Preventing the Formation of cale.
We, HARRY SCHOFIELD, of 1A, Bryantwood Road, Drayton Park, N., Engineer,
and OLIVER PRESCOTT MACFARLANE, of 7, Hartham Road, Camden Road,. N.,
Accountant, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in apparatus for promoting or increasing
the circulation of the water in steam generators or boilers and also for collecting
the solid matter held in suspension in said water, or such solid matter as may be
stirred up by the effect of circulation-and for preventing the formation of scale.
In carrying out this invention we use preferably a pipe or similar conductor
fixed within the boiler and bent or formed in such a manner that the upper end
is situated a little below the working level of the water and at a point at or near
that where the greatest heat exists while the lower end of the pipe is carried to
a point near the bottom of the boiler where the water has the lowest temperature.
The pipe, which is preferably made smaller in diameter at the upper or discharging
end in order to increase the current passing through it, is secured in position by
rods clamped to the boiler stays or other suitable attachment.
By a modification of the foregoing, the continuity of the pipe or conductor may
be broken near the upper end, and a mudbox or cylinder introduced, of greater
sectional area then the pipe, the object of which is to reduce the velocity of the
current in passing through the mud-box or cylinder and allow the solid matter
taken up by the water to be deposited therein. The mud-box or cylinder may be
fitted internally with a baffle plate or plates and also a sludge discharge pipe
carried to a point near the bottom of the mud-box or cylinder and passing through
the boiler shell, this sludge-pipe is fitted with a tap or cock which may be opened
when required in order that the sludge may be blown through and deposited at
some convenient place outside the boiler.
It is obvious that one or more pipes or conductors may be fitted in the same
boiler, each having a separate mud-box, or one mud-box of larger area may be used
to which all the pipes would be connected. The discharging end of the pipe or
conductor may also be branched and formed to lead jets of water to any desired
position in the boiler.

page_text: Improvements in Apparatus for Promoting the Circulation of Water
in Steam Generators and Boilers, and collecting the solid Matter
in same, and for Preventing the Formation of scale.
We, HARRY SCHOFIELD, of 1A, Bryantwood Road, Drayton Park, N., Engineer,
and OLIVER PRESCOTT MACFARLANE, of 7, Hartham Road, Camden Road, N.,
Accountant, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement;-
-
This invention relates to apparatus for promoting or increasing the circulation
of the water in steam generators or boilers and is applicable more particularly to
the kind of steam generators in which internal furnaces are employed such as
Lancashire, Cornish, Galloway and marine boilers.
The said apparatus may be adapted also for collecting the solid matter held in
suspension in the water or stirred up by the effect of circulation and for preventing
the formation of scale.
•
According to our said invention we employ one or more circulation pipes or con-
duits arranged within the steam generator, and bent or formed in such a manner
that the upper end thereof is situated a little below the working level of the water
or at a point where the water has the highest temperature while the other or lower
end of such pipes is situated near the bottom of the water space or at a point where
the water has the lowest temperature. This difference in temperature at the
extremities of the pipes sets up the desired circulation.
The collection of the solid matter may be effected by a settling chamber or mud-
box interposed in the length of the circulation pipe..
In order that my invention may be clearly understood and readily carried into
effect I will proceed to describe the same more fully by aid of the accompanying
drawings, in which:-
Figure 1 is a longitudinal section
Figure 2 a horizontal section, and
Figure 3 a transverse section on the line of Figure 1, of a Lancashire boiler,
showing one form of my improved apparatus applied thereto.
Figure 4 is a detail view illustrating a slight modification in which the outlet
end of the circulation pipe is forked or branched.
A is the shell of the boiler, B B are the furnace flues, C.C are the fire bridges in
the said flues, DD are the fire bars and E is a line indicating the water level.
a represents a circulation pipe of the kind referred to, which. in the present
--instance is advantageously arranged between the flues B, although it may be placed
in any other suitable position.
The lower end b of this pipe terminates as shown in the angle at the lower front
part of the boiler, which is usually the coldest part, while the upper end c of the
pipe is preferably tapered to form a jet or nozzie and lies just a little below the
:water level.
It will be seen that the pipe a consists essentially of two horizontal portions
connected by easy bends or curves with a vertical portion situated near the fire-
bridges C where the heat is greatest.
This is a very convenient form of pipe to employ but obviously a pipe of any
other suitable form, for instance one which is straight or curved and inclined may
be employed if desired.

page_text: d is a settling chamber or mud-box which is situated above and to the rear of
the fire-bridge and is interposed in the length of the circulating pipe, so that the
water flowing through the pipe has its velocity greatly decreased in the said
chamber, and any suspended matter therein will be caused to deposit.
The said chamber or mud-box may be comparatively narrow at the bottom to
better collect the sediment, and has inclined or converging side walls which enable
it to fit better between the furnace flues B.
The settling chamber is provided with suitable baffle plates, arranged vertically,
horizontally or otherwise, to cause the sediment to collect more readily. In the
example illustrated such a baffle plate is shown at e, this plate depending from
the cover of the settling chamber.
The circulation pipe and the settling chamber are supported in any convenient
manner for example by suitable hooks or the like connected to cross bars g¹
resting on the boiler stays g².
h is a sludge pipe which extends from the lower part of the settling chamber,
and i is a throttle valve which may be fitted in the upper part c of the pipe a to
enable the latter to be closed if desired when blowing off sludge.
The throttle valve is connected to a spindle i¹ which passes through a stuffing
box 22 secured in the boiler shell. Within this stuffing box is a space into which
the sludge pipe h opens at a point inside the boiler, while outside the boiler a
second sludge pipe h₁ leads the sludge from the said space 2, and terminates at any
suitable place where the sludge may be blown off without causing inconvenience.
This pipe is controlled by a sludge cock (not shown) near its outer extremity.
Any sediment forming at the bottom of the boiler is drawn by the circulation
current up the tube a becomes deposited in the settling chamber or mud-box d
whence it can be blown off through the sludge pipes and h. The liability to
scaling of the boiler is thus greatly diminished.
By closing the throttle valve i, the stream of water which rushes into the set-
tling chamber, when the sludge pipes are opened can only enter from the lower end b
of the circulation pipe, and consequently the scale or sediment collecting in the
latter is carried away, and discharged through the sludge pipes.
We do not however propose to employ the throttle valve in all cases, and when
we dispense with it we simply carry the pipe h direct through the boiler
shell and connect it to the pipe outside the latter.
It will be readily understood that we may if desired employ the circulation pipe
alone, without using a settling chamber in conjunction therewith. We prefer
however to employ the two together as previously described.
In the arrangement shown in Figure 4, the upper end c of the circulation pipe
is provided with two diverging branches or nozzles c¹ to better distribute the current
of water which flows up through the pipe.
In cases where two or more circulation pipes are employed each of them may
be provided with a settling chamber or mud box, or a number of such pipes may be
arranged to communicate with a single settling chamber.
Moreover instead of employing a pipe such as a, we may employ any equivalent
device such as a long narrow chamber capable of forming a path or channel for
the circulation current to flow through; or the pipe may be flattened or of any
desired shape in cross section.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is: -
1. A circulation pipe or its equivalent arranged inside a boiler, and leading
from the lower and cooler part to the upper and hotter part thereof, substantially
as and for the
described.
purposes
2. The combination with a circulation pipe such as referred to in the preceding
claim, of a settling chamber or mud-box to collect the sediment in the water flow-
ing up said pipe, substantially as described.

page_text: 3. An apparatus for promoting the circulation of water in steam generators and
boilers and for collecting the solid matter in the same and preventing the formation
of scale, substantially as described with reference to the accompanying drawings.
Dated this 11th day of August 1898
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.