IMPROVED MEANS FOR PRODUCING THE CIRCULATION OF WATER IN STEAM BOILERS
Year: 1884

page_text: I, ARTHUR WILLIAM LOVELL REDDIE of the Office for Patents 66 Chancery
Lane in the County of Middlesex Patent Agent, do hereby declare the nature of
my Invention for IMPROVED MEANS FOR PRODUCING THE CIRCULATION OF
WATER IN STEAM BOILERS to be as follows:-
It is well known by marine engineers that in getting up steam in modern
marine boilers more particularly those of large size, the water which is in the
upper part of the boiler and which is in contact with the upper parts of the
furnaces and the tubes and tube sheets becomes heated more quickly than the water
in the lower parts of the boiler.
In some marine boilers if steam is got up quickly it will be found that the
temperature in the upper part of the boiler will be even as high as 300 degrees
Fahrenheit while at the bottom of the boiler it may be below 50 degrees. In fact
in most modern marine boilers the water will be. comparatively cold at the
bottom of the boiler for several hours after.steam is got up and the engines are
running.
The consequence is a very slow circulation and comparatively low temperature
in the lower parts of the boiler and a high temperature in the upper parts of the,
boiler.
It is obvious that with a number of large boilers the quantity of water to be
moved to produce an effective circulation in all, more especially when getting up
steam is very great; while at the same time, the room available for means to
produce a circulation from the lower to the upper parts of the boiler is limited.
The object of this Invention is to provide a means which shall be more effective.
than any heretofore used in producing the necessary circulation which shall occupy
but little room and which may be applied to boilers at a comparatively
small cost.
To this end the Invention consists essentially in the combination with a steam
boiler of an injector or injecting device, a suction or supply pipe leading from one

page_text: portion of the boiler to the water inlet of the injector and a discharge pipe leading
from the injector to another portion of the boiler whereby the injector will serve
to circulate the water from one part to another of the boiler. The injector may
have only a single suction or supply pipe but it is preferred to provide two or
more suction, or supply pipes leading from the lower portion of the boiler at
different parts thereof each provided with a valve whereby the passage through it
may be controlled thus providing for increasing or diminishing the quantity of
water taken through either suction or supply pipe, as the temperature of the water
at one part or another of the boiler may be greater or less.
When the fires are first lighted in the boiler and before steam is generated the
steam for operating the injector may be taken from the donkey boiler through a
branch steam pipe.
The apparatus may be so connected as to take water from the upper part of the
boiler and produce a circulation by delivering it into the lower part thereof.
By the operation of the injector a rapid circulation is kept up and any
considerable differences in temperature in different parts of the boiler are prevented.
The injector may be kept in operation as long as desired and the fireman or
engineer by means of adjusting valves can increase or diminish the quantity of
water taken from different parts of the boiler as may be necessary to preserve a
temperature as nearly uniform as possible.
But as single pipe may be used to connect the lower part of the injector with
the boiler.
Dated this 26th day of February 1884

page_text: I ARTHUR WILLIAM LOVELL REDDIE of the Office for Patents 66 Chancery
Lane in the County of Middlesex, Patent Agent do hereby declare the nature of
my Invention for IMPROVED MEANS FOR PRODUCING THE CIRCULATION OF WATER
IN STEAM BOILERS and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:―
It is well known by marine engineers that in getting up steam in modern marine
boilers more particularly those of large size, the water which is in the upper part
of the boiler and which is in contact with the upper parts of the furnaces, and the
tubes and the tube sheets, becomes heated more quickly than the water in the
lower parts of the boiler.
In some marine boilers if steam is got up quickly it will be found that tlie
temperature in the upper part of the boiler will be even as high as 300 degrees
Fahrenheit, while at the bottom of the boiler it may be below 50 degrees. In fact
in most modern marine boilers the water will be comparatively cold at the bottom
of the boiler for several hours after steam is got up and the engines are running.
When such differences in temperature exist in the boiler, it is evident that
the parts which are effected by the differences must be subjected to enormous
strain and greatly weakened by reason of unequal expansion, and especially is this
true of such parts as are most exposed to the heat of the fire, such as the furnaces,
back connections, tubes, and tube sheets.
At any time but very little steam is generated below the grate bars of the
modern marine boiler, and the consequence is a very slow circulation and
comparatively low temperature in the lower parts of the boiler and a high
temperature in the upper parts of the boiler; and it is undoubtedly a fact that
boilers are greatly weakened and their life shortened by such constant and
considerable differences of temperature.
Large steam ships have a number of large boilers, some ten or more, and it is
obvious that the quantity of water to be moved to produce an effective circulation
in them all, especially in getting up steam, is very great; while at the same time
the room available for.means to produce a circulation from the lower to the upper
parts of the boiler is limited.
The object of my Invention is to provide a means which shall be more effective
than any heretofore used in producing the necessary circulation, which shall occupy
but little room and which may be applied to boilers at a comparatively small cost.
To this end my Invention consists essentially in the combination with a steam
boiler of an injector or injecting device, a suction or supply pipe leading from one
portion of the boiler to the water inlet of the injector and a discharge pipe leading
from the injector to another portion of the boiler whereby the injector will serve
to circulate the water from one part to another of the boiler. The injector may
have only a single suction or supply pipe but I prefer to provide two or more suction
or supply pipes leading from the lower portion of the boiler at different parts
thereof and each provided with a valve whereby the passage through it may be
controlled, thus providing for increasing or diminishing the quantity of water
taken through either suction or supply pipe, as the temperature of water at one
part or another of the boiler may be greater or less.
In the accompanying Drawing Figure 1 is a front elevation of a boiler having
my Invention applied to it for producing a circulation from the lower to the upper
part of the boiler the discharge pipe of the injector being broken away or removed
to expose the injector behind it and the injector being in section; Fig. 2 is a

page_text: .
vertical section on the line x, x, Fig. 1, showing the front end portion of the
boiler; and Fig. 3 is a plan of the parts embodying my Invention and a portion
of the extreme front of the boiler.
Similar letters of reference designate corresponding parts in all the Figures.
A designates the boiler which is shown as having three furnaces A¹, and at the
front of which the injector B, is placed.
The injector and its connections may be placed in any other position, as for
example at the back or side of the boiler, but when at the front of the boiler it
is within reach of the fireman or engineer and is therefor more convenient of
access.
.
The injector or injecting device may be of any well known type.
As here shown the injector B is connected by two pipes C, C, with the lower
part of the boiler at opposite sides of and below the lowermost furnace A¹, and in
these pipes are valves C¹, C¹, whereby the passage of water from the lower part of
the boiler upwards to the injector can be controlled; D designates the discharge
pipe which as here shown extends from the lower end of the injector and then
upwards as shown in Figure 2 in front of the injector and into the boiler. The
injector may be arranged to discharge in any other direction than downwards.
This discharge pipe may enter the boiler a short distance below the water line,
which is represented by the dotted line W, and is broken away or partly removed
in Fig. 1 in order to show the injector which is behind it. The pipe D is provided
with a valve D¹ which may be closed when the injector is not in operation.. The
pipe D might enter the boiler above the water line if desired.
The suction and discharge pipes C and D may terminate openings in the shell of
the boiler but I prefer for the purpose of obtaining a circulation of water
throughout the whole length of the boiler to provide inside the boiler and in
communication with the said pipes C, D, (as shown in Fig. 2.) perforated pipes C*
and D* which form prolongations of the said pipes CD and are long enough to
reach from that end of the boiler where the said pipes C D are placed, to or
nearly to the opposite end of the boiler, the said perforated pipes, C* D*, being
closed at the ends further from CD, and 'each having the sum of the areas of its
perforations equal to the area of its internal transverse section. The water
entering the pipes C and delivered from the perforated pipe or pipes D* is thus
caused to be taken from and delivered to all parts of the length of the boiler and
thus a more perfect circulation throughout the whole of the boiler is made than if
the pipes CD terminated at orifices in the shell of the boiler without any
pipes C* D*.
1
E designates a steam pipe leading from the main steam space of the boiler and
provided with a stop valve E¹; and E2 designates a branch steam pipe which is
provided, with a valve E³ and with which is to be connected a pipe extending from
the donkey boiler usually used on steam ships and which is not here shown.
4
The steam enters the injector through the nozzle or orifice a under control of
the usual valve a¹, and b designates the passage through which the steam and the
current of water induced thereby pass downwards to the discharge D and thence
into the boiler. At the bottom of the bend in the discharge pipe D is the usual
overflow or try cock.c.
When the fires are first lighted in the boiler. and before steam is generated the
steam for operating the injector is taken from the donkey boiler through the branch
steam pipe E. The donkey boiler as commonly used is employed for supplying
steam to steam hoisting engines, pumps, etc., but by the time the fires are started
in the main boilers the hoisting of cargo is generally about completed, and
consequently the donkey boiler will furnish an ample supply of steam for the
injectors on the several boilers, at least one being applied to each boiler:
The valve E³ being opened and the valve a¹ properly adjusted the steam issues
from the orifice a into the passage b and induces a current through the discharge
pipe D, and 'when the valves C, C', are opened there will be a circulation of water
from the lower to the upper part of the boiler. This circulation is continued until

page_text: steam of sufficient pressure to work the injector is generated in the main boiler
whereupon the valve E³ is closed and the valve E¹ opened and thereafter the steam
for operating the injector as long as may be desired is taken from the main
boiler.
The apparatus may be so connected as to take water from the upper part of
the boiler and produce a circulation by delivering it into the lower part thereof.
By the operation of the injector a rapid circulation is kept up and any
considerable differences in temperature in different parts of the boiler are prevented.
The injector may be kept in operation as long as desired, and the fireman or
engineer by adjusting the valves C¹ can increase or diminish the quantity of water
taken from different parts of the boiler as may be necessary to preserve a
temperature as nearly uniform as possible.
But a single pipe C may be used to connect the lower part of the injector with
the boiler.
From the above description it will be seen that I provide a means which will be
effective in circulating the water in the largest boiler, which may be applied at
comparatively small cost, and which will occupy little space.
The apparatus is preferably entirely supported from the boiler, and from Figs. 2
and 3 it will be seen how slightly it projects beyond the front of the boiler when
it is arranged in that position.
In a steamship I intend to provide each of the main boilers with an injector
combined with the boiler as herein described and when the fires are started the
injectors will all be supplied with steam from the donkey boilers.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is :-
1st The combination with a steam boiler, of an injecting device, a suction or
supply pipe leading from the boiler to the water inlet of the injecting device, and
a discharge pipe leading from the injecting device to the boiler, for the purpose of
producing a circulation of water from one part of the boiler to another part thereof,
substantially as described and for the purpose set forth.
2nd The combination with a steam boiler of an injecting device, a suction or
supply pipe leading from the lower part of the boiler to the water inlet of the
injecting device, and a discharge pipe leading from the injecting device to the upper
part of the boiler for the purpose of producing a circulation of water from the
lower to the upper part of the boiler substantially as described.
3rd The combination with a steam boiler, of an injector, two suction or supply
pipes provided with valves and leading from the boiler at opposite sides thereof to
the water inlet of the injector, and one or more discharge pipes leading from the
injector to another part of the boiler, whereby provision is afforded for circulating
the water in the boiler and for varying the quantity of water supplied to the
injector from different parts of the boiler, substantially as herein described.
4th The combination with the boiler and the suction and discharge pipes of the
injector, of the perforated pipes C* D* forming prolongations of the said suction
and discharge pipes within the boiler substantially as and for the purpose herein
described.
Die 17th day of Annil 1001.