Improvements in Feed Water Heaters.
Year: 1892

page_text: Date of Application, 30th Sept., 1892
Complete Specification Left, 30th June, 1893-Accepted, 5th Aug., 1893
PROVISIONAL SPECIFICATION.
Improvements in Feed Water Heaters.
I, JOHN NOBLE, of 48 Marine Approach, South Shields, in the County of
Durham, Superintendent Engineer, do hereby declare the nature of this invention
to be as follows:-
My invention relates to an improved apparatus for heating the feed water for
steam boilers whereby more efficient heating with greater economy of steam is
secured. It is applicable to any steam engine but being specially designed for
marine engines I will describe it as constructed for such engines.
"
Instead of using "live" steam from the boiler or merely the exhaust steam after
it has done its work in the engine I propose to use steam from the intermediate
steam chest of triple expansion, or from that of the low pressure cylinder in simple
compound engines, admitted into one end of a copper coil-preferably double-
enclosed within a pipe through which the feed water from the hotwell is caused to
circulate by the feed pump on its way to the boiler the quantity of water passing
through and around the coil being regulated by an adjustable check valve connected
to the delivery of the feed pump.
The coils are secured at each end in the enclosing pipe by screwed coupling
sockets which are so constructed that whilst making perfectly steam tight con-
nection they can be readily disconnected to enable the coils to be withdrawn when
required for examination, cleaning or repairs. The steam enters at one end of the
coils the quantity being regulated by a cock and, after traversing the entire length
of the pipe containing the feed water and heating the same, the condensed steam
water is discharged at the other end by a drain pipe into the hotwell.
The pipe enclosing the steam coils is preferably made much larger in area than
the feed pipe so that at each stroke of the feed pump only a portion of the water
around the coil is delivered to the boiler, the pipe thus acting as a reservoir of feed
water being heated, and the self-closing check valve stops the return of the water
into the delivery pipe of the feed pump.
I have found that the quantity of steam required to raise the feed to a very high
temperature by this apparatus is very small and, being taken from the engine after
it has acted in the high pressure cylinder, the effective power of the intermediate
cylinder or of the low pressure cylinder as the case may be is very little impaired
as compared with feed heating by "live" steam from the boiler and that any such
loss of power is much more than compensated in economy of fuel by the high
temperature of the feed water.
Dated this 30th day of Sontember 1809
T. J. DANSON,
By L. W., per F. B.
COMPLETE SPECIFICATION.
Improvements in Feed Water Heaters.
I, JOHN NOBLE, of 48 Marine Approach, South Shields, in the County of
Durham, Superintendent Engineer, 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 :-
My invention relates to an improved apparatus for heating the feed water for
steam boilers whereby more efficient heating with greater economy of steam is
secured. It is applicable to any steam engine, but being specially designed for
marine engines I will describe it as constructed for such engines.

page_text: Instead of using "live" steam from the boiler, or merely the exhaust steam after
it has done its work in the engine, I propose to use steam from the intermediate
steam chest of triple expansion, or from that of the low pressure cylinder in simple
compound engines, admitted into one end of a copper coil-preferably double-
enclosed within a pipe through which the feed water from the hotwell is caused to
circulate by the feed pump on its way to the boiler, the quantity of water passing
through the pipe and around the coil being regulated by an adjustable check valve
connected to the delivery of the feed pump.
The coils are secured at each end in the enclosing pipe by screwed coupling
sockets which are so constructed that, whilst making perfectly steam tight con-
nection, they can be readily disconnected to enable the coils to be withdrawn when
required for examination, cleaning, or repairs. The steam enters at one end of the
coils, the quantity being regulated by a cock, and, after traversing the entire length
of the pipe containing the feed water and heating the same, the condensed steam
water is discharged at the other end by a drain pipe into the hotwell.
The pipe enclosing the steam coils is preferably made much larger in area than
the feed pipe so that at each stroke of the feed pump only a portion of the water
around the coils is delivered to the boiler, the pipe thus acting as a reservoir of feed
water being heated, and the self closing check valve stops the return of the water
into the delivery pipe of the feed pump.
I have found that the quantity of steam required to raise the feed to a very high
temperature by this apparatus is very small, and, being taken from the engine after
it has acted in the high pressure cylinder, the effective power of the intermediate
cylinder or of the low pressure cylinder as the case may be-is very little impaired
as compared with feed heating by "live" steam from the boiler, and that any such
loss of power is much more than compensated in economy of fuel by the high
temperature of the feed water.
On the accompanying sheet of drawings my invention is shewn in the form in
which I propose to apply it practically, though I may make certain modifications in
details to meet special cases.
Fig. 1 is a longitudinal section, Fig. 2 a cross section of the apparatus in which
a double steam coil is used, as I prefer to make it, and Fig. 3 is a section (full size)
of one of the coil couplings.
A. is the chamber through which the feed water passes from the adjustable check
valve B., in connection with the feed pump, by the pipe C., and, after being heated
by contact with the double steam coils D D³, is discharged at each stroke of the
pump to the boiler at E.
The coils DD' are made of copper tube and are connected at their ends with the
chamber A. by means of screwed coupling sockets F F¹ brazed on the tubes, into
which sockets, when the coils are in position in the chamber A., "nipples" G G¹
are screwed by a canted collar formed upon them, the screwed outer ends of said
nipples receiving a union on the ends of the steam pipes and drain pipes respectively.
The construction of the screwed coupling sockets F F and of the "nipples " G G¹
is shewn on the full size section Fig. 3.
The coils D D are inserted through one end of the chamber A. and, when the
couplings F F are in position opposite the holes in the ends of the chamber, the
nipples" G G¹ are inserted and screwed up so as to draw the flanges or couplings,
which are curved to the inside diameter of the chamber, into close contact with it
and so make a perfectly tight joint.
The steam from the intermediate steam chest in triple compound (or from the low
pressure steam chest in simple compound) engines, controlled by a cock or valve,
enters at the "nipples" G G³, and traversing the interior of the coils D D' heats
the feed water in the chamber A. in contact with the outside of the coils and the
condensed steam, as water, drains into the hotwell through a pipe from the

page_text: 66
"
"nipple
at opposite end. When it is required to examine or clean the coils
the nipples" are unscrewed and one end of the chamber being opened the coils
can be withdrawn.
Although I have not named quadruple expansion engines it will be evident that
my invention is equally adapted for that type, and the steam for the coils may be
taken from the steam chest of either the second or third cylinder, preferably the
latter.
In actual working I have found that, as compared with the use of "live" steam
from the boiler, there is a saving effected in fuel of 71% to 10%, while, as
compared with the use of exhaust steam, the higher temperature of the feed water
effects a similar economy of fuel. The apparatus requires very little attention
beyond cleaning about every 4 to 6 months, occupies small space, and reduces the
wear and tear on check valves which work quite silently.
Having now particularly described and ascertained the nature of said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
First. The improvements in feed water heaters consisting in passing steam, which
has operated in the first cylinder in triple or simple compound engines, or in the
first and second cylinders in quadruple compound engines, through one or more
coils enclosed in a chamber through which the feed water is caused to circulate
around said coils substantially as described and in one form illustrated.
Second. The method of fixing and making steam and water tight the coils in the
chamber by the screwed coupling sockets F F and the screwed "nipples" G G',
whereby the coils can be readily uncoupled and withdrawn from the chamber for
examination, cleaning, or for repairs, substantially as described and shewn.
Dated this 20th day L. 1902
T. J. DANSON, F. Inst. P.A.,
Chartered Patent Agent,
Newcastle-upon-Tyne, Agent for Applicant.
T. J. DANSON, F. Inst. P.A.,
Chartered Patent Agent,
Newcastle-upon-Tyne, Agent for Applicant.