IMPROVEMENTS IN INJECTORS FOR RETURNING WASTE OR EXHAUST STEAM TO THE BOILER
Year: 1884

page_text: I, THOMAS BUDWORTH SHARP of French Walls, Smethwick in the county of
Stafford Mechanical Engineer do hereby declare the nature of my invention for
IMPROVEMENTS IN INJECTORS FOR RETURNING WASTE OR EXHAUST STEAM TO THE
BOILER to be as follows:-
.
Some methods of returning to the Boiler Exhaust or waste steam by the lateral
or inductive action of jets of water or steam while passing through an injector
have been
By introducing it into the steam nozzle either centrally or annularly so as to be
drawn along and mingle with the live steam-or by introducing it at the overflow
in which case it is condensed and drawn along with the jet and taken into the.
boiler. But neither of these methods have given satisfaction, the first because of
the liability of air existing in the exhaust steam & which of course does not
condense with the steam but is merely taken along with the current in the form of
globules and when it arrives at the overflow it causes the jet to spit or altogether
burst and stop the action of the injector; and the second because of its inter-
ference with the overflow which at starting especially should always be free and
open.
Now my invention consists in taking in the exhaust at a point between the
overflow and the point at which the delivery water from the injector mingles with
the water in the boiler and the apparatus I employ may either form a part of the
injector or be a sepparate appliance altogether and fixed any-where on the delivery.
It resembles in its action the method of taking in steam at the overflow but it has
the advantage of being apart from it and not in any way interfering with it. The
delivery is contracted into a nozzle to about the same diameter as the throat or
receiving nozzle of the injector & in consequence of this contraction the water is
thrown with considerable velocity forwards it is then allowed to pass unconfined at
its sides by any nozzle or walls through a short open space and is then projected
into a bell mouthed nozzle the narrowest part of which is also about equal to the
throat of the injector this narrowest part then again diverges so as gradually to
convert the velocity of the jet Back again into pressure.

page_text: Into this clear open space referred to I introduce by means of a side branch or
pipe the exhaust or waste steam which is condensed and carried along by the jet
and taken into the boiler.
The exhaust branch of this apparatus has a back pressure valve or clack box
opening in the direction of the flow of the exhaust and the object of this valve
is to prevent any escape down the exhaust pipe of water which is intended for the
boiler & which at starting has not enough force to jump across the open space with
sufficient force to enter the boiler but would if not checked go down the exhaust
pipe.
The economy of this apparatus is rendered very manifest if it is placed say at
the middle of the delivery pipe; for by placing one hand on that part which leads
to the apparatus and the other on that part which leads from the apparatus the
higher temperature of the outlet is very striking and this difference of temperature
is a source of gain or rather a recovery of heat already expended.
L

page_text: I, THOMAS BUDWORTH SHARP of French Walls, Smethwick in the county of
Stafford, Mechanical Engineer do hereby declare the nature of my invention for
IMPROVEMENTS IN INJECTORS FOR RETURNING WASTE OR EXHAUST STEAM TO THE
BOILER and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :—
Some methods of returning to the Boiler exhaust or waste steam by the lateral
or inductive action of jets of water or steam while passing through an injector
have been-By introducing it into the steam nozzle either centrally or annularly
so as to be drawn along and mingle with the live steam-or-by introducing it
at the overflow in which case it is condensed and draun along with the jet and
taken into the boiler-But neither of these methods have given satisfaction the
first because of the liability of air existing in the exhaust steam and which of
course does not condense with the steam but is merely taken along with the
current in the form of globules and when it arrives at the overflow it causes the
jet to spit or altogether burst and stop the action of the injector and the second
because of its interference with the overflow which at starting especially should
always be free & open.
Now my invention consists in taking in the exhaust at a point between the
overflow and the point at which the delivery water from the injector mingles with
the water in the boiler and the apparatus employ may either form part of the
injector or be a separate appliance altogether and fixed anywhere on the delivery.
It resembles in its action the method of taking in steam at the overflow but it has
the advantage of being apart from it and not in any way interfering with it.
The delivery is contracted into a nozzle of about the same diameter as the throat
or receiving nozzle of the injector and in consequence of this contraction the water
is thrown with considerable velocity forwards it is then allowed to pass unconfined
at its sides by any nozzle or walls through a short open space and is then projected
into a bell mouthed nozzle the narrowest part of which is also about equal to the
throat of the injector this narrowest part then again diverges so as to gradually
convert the velocity of the jet back again into pressure.
Into this clear open space referred to I introduce by means of a side branch or
pipe the exhaust or waste steam which is condensed and carried along by the jet &
taken into the boiler.
The exhaust branch has a back pressure valve or clack box opening in the
direction of the flow of the exhaust and the object of this valve is to prevent any
escape down the exhaust pipe of water which is intended for the boiler and which
at starting has not enough force to jump across the open space with sufficient force"
to enter the boiler but would if not checked go down the exhaust pipe.
The economy of this apparatus is rendered very manifest. if it is placed say.at the
middle of the delivery pipe for by placing one hand on that part which leads to thie
apparatus and the other on that part which leads from the apparatus the higher
temperature of the outlet is very striking and this difference of temperature is of
course a source of gain or more correctly speaking a recovery of heat already
expended.
+
I will now proceed to explain with reference to the accompanying sheet of
drawings the manner in which my invention may be performed and in doing so

page_text: I will specially select for illustration that particular form which I have designed as
being in my opinion best suited for the use of Locomotive Engines.
Fig 1 is a section of it and Fig 2 is a skeleton outside view of a portion of a
Locomotive shewing the way in which I think it may be best applied.
The action and construction of this apparatus is so apparant as to need but little
description.
A is the pipe conveying the warm water which has passed the overflow space
in the Injector & F is the contracted point which projects the jet from F to G & it
is while taking this jump that it condenses the exhaust steam and is thereby
heated and then passing out at K it enters the boiler through the clack box B
after having traversed the pipe,C. B.
In working out this invention I find that the waste steam has an accellerating
effect on the jet.
His the back pressure valve which prevents any water from passing into the
exhaust E by means of D E-it remains closed till the injector has started when it
is assisted in opening by means of the partial vacuum created inside the casing by
means of the inductive action of the jet F. G. & as long as there is a flow of steam
or air in the direction E D so long will it remain open but should that flow cease
then it closes.
Of course I might have bolted the flange L M directly onto the delivery flange
of the injector or the nozzle F might have even been a part of the same piece of
metal as the receiving nozzle of the injector but I like the form I have illustrated
best for Locomotive and indeed for all practical purposes because its value is at all
times so apparant in the difference of temperature of the pipes A C & C B.
I will now give an idea of what this economy may some times be :-Suppose we
take the temperature of the feed at say 56° F (which is about the natural tem-
perature of feed water in England) in passing through the injector its temperature
is increased by say 60° F; that is, brought up to say 116° F; at this temperature it
enters my apparatus and in passing over-the space F. G. it takes up enough exhaust
steam to raise it say 90° F which brings it up to say 206° F thus economizing fuel
to an extent equivalent to an elevation of temperature in the feed water of 90° F.
As however the precise details herein described & illustrated may be considerably
varied without departing from the nature of my invention I wish it to be under-
stood that I do not limit myself to the said precise details but can vary them
considerably according to the circumstances of the case and as my experience
dictates without exceeding the limits of my patent. For instance where I prefer
it I can have a second contracted nozzle and a second space corresponding in its
action to F. G. or even a third or more if requisite or I may introduce the exhaust
into the centre of the jet instead of annularly, but I prefer to any other the form
I have selected for illustration because of its great simplicity to manufacture & for
cleaning.
Having now particularly described & ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is
Leading exhaust or waste steam into contact with a jet or current of water after
-such water has passed the overflow space in an injector in such a manner that the
said jet or current will condense the said exhaust or waste steam & thereby become
heated substantially as described and illustrated and for the purposes set forth.
Dated this twenty seventh day of February 1885.