Improvements in Feed Water Heating Apparatus for Steam Boilers and the like.
Year: 1888

page_text: Date of Application, 21st July, 1888
Complete Specification Left, 20th Apr., 1889
Complete necification Accepted, 1st June. 1889
PROVISIONAL SPECIFICATION.
Improvements in Feed Water Heating Apparatus for Steam Boilers
and the like.
I, LEVI HUSSEY, of 15 Courtlandt Street, New York, United States of America,
Engineer do hereby declare the nature of this invention to be as follows:-
:-
The invention relates generally to that class of water heating apparatus that is
employed for supplying steam boilers and other large tanks, and it relates particularly
to such apparatus when constructed and designed for use in a steam boiler or
other flue to heat the feed water of the boiler, or for use in a similar passage or
conduit of gases of combustion for the purpose of heating water for large tanks
of any kind. The invention will be described as embodied in a feed-water heater
for a steam boiler, but it is to be understood that it is applicable to other like
purposes without material change.
It is well known that when cold water is fed into the pipes of a feed-water heating
apparatus, as heretofore arranged in boiler flues, the variation of temperature
between the inner and outer surfaces of the heating parts will, within certain limits
known as the "dew point," produce sweating or condensation of moisture on the
outer surfaces and, such outer surfaces being exposed to the varying heat of the
gases and the waste products of condensation in the furnace flue, a rapid oxidation
and encrustation takes place thereon and the parts are rapidly destroyed. Usually
such heating surfaces consist of coils or banks of pipes, this form of beater being
usually necessary in order to secure the greatest heating surface in the smallest
space, it being desirable to not greatly enlarge the flue; and the rapid eating away
of such pipes and consequent liability to explosion, together with the cost and
inconvenience of replacement of the parts, is a fault of the common form of heaters
that it is of the greatest importance to obviate.
A further objection to the common form of heaters is that, by reason of the
fluctuating temperature of the contained water and its irregular motion through the
pipes, deposits of lime, mud and like impurities in the water are deposited within
the pipes and act to clog them and thereby seriously interfere with the working
canacity of the heater.

page_text: It is the object, therefore, of the present invention to construct a water heater and
arrange its various parts so that the water will be preliminarily heated beyond the
dew point or the point where sweating would occur, before it passes into the heater or
the bank of pipes where it is raised to its highest temperature, thereby preventing the
fluctuations of temperature in such pipes that produce exterior deterioration of their
surfaces, and also so that the motion of the water through such pipes will be
continuous and practically constant, thereby preventing deposits in these pipes and
consequent clogging thereof.
In carrying the said invention into practice the boilers may be arranged in a bank
or series and the smoke flue may be common to the boilers. The said flue conducts
the products of combustion to the chimney. This flue is made of a sufficient size to
contain the apparatus located therein without interfering with the draught necessary
to the furnaces; and it may be the flue leading from a single or any number of boilers,
or it may be any suitable part of any similar passage for conducting away the gases
and products of combustion from any furnace or similar chamber of combustion.
The receiving tank of the feed water heating apparatus consists of a cylindrical
shell, the lower half of which is pierced from end to end by open heating tubes
through which the gases of the flue circulate. This receiver is connected by a pipe
with the supply tank, which is open at the top and provided with a float connected to
the steam pump in such a manner that as the water becomes lowered in the tank the
pump will be caused to operate and supply the receiver through the feed pipe.
The bottom courses of the water heating coil or heater are connected with the bottom
of the receiving tank, and the arrangement of its successive courses is such that the
circulation of the water is upwardly from course to course. This arrangement of the
heating pipes is not, however, essential in itself; any suitable arrangement of the pipes
whereby a large heating surface is secured in a small space will answer.
The reservoir from which the heated water is taken to charge the boilers_consists of
a cylindrical shell, the heads of which are pierced with open heating tubes L reaching
from one head to the other and extending from the bottom to the top of the reservoir.
From the top of the reservoir rises the outlet pipe to which is joined the inlet pipe
running to a pump by which the heated water is forced into the boilers, or any one of
them. The outlet pipe continues over as a vapor pipe to and enters the supply tank
to just beneath the surface of the water therein. A blow-out pipe is provided for this
reservoir, and a blow-out pipe for the tank is also provided by which these receptacles
may be cleared of whatever deposit collects in thein.
These structures constitute the essential part of the feed water heating apparatus.
They will be built in size and working capacity to correspond with the work required
of them and the available heat of the flue in which they are placed. This balancing
of these parts, each to the others, and all to the boilers they are to serve, is important
to the economical working of the apparatus in the best way; but as these are matters
of engineering knowledge, it is not essential to enter upon a full explanation thereof
here. It may be noted, however, as one of the important features of construction,
that the receiving tank should be of such size that the water will not in ordinary
practice be drawn through it so rapidly as to enter the heating coils at a temperature
varying from a uniform or practically uniform temperature, which temperature of
course it is designed shall always be above that where sweating of the coils would
occur.
The operation is as follows: It is first to be understood that the heated gases of the
flue are circulating around and through the reservoir, the super-heater and the receiving
tank, and thereby tending to raise the temperature of their contents. As the water
comes in at the top of the receiving tank it meets the heated water already there,
and mingling with the same and passing around and between the tubes of this
receiver, it is brought to a temperature above the dew point, for this apparatus as it
sinks to the bottom thereof. From the receiving tank the water passes to the
super-heater, in which, by reason of the large heating surface thereof, it is brought to
the desired final temperature, that is, to very nearly boiling point. From the heating
coil the water passes into the bottom of the supply reservoir, where its temperature is

page_text: maintained, or slightly increased if desired, by circulating around the tubes of this
reservoir and mingling with the contents thereof as it ascends to the outlet pipe, from
which it is drawn and forced into the boilers in a condition at or just below the point
of vaporization.
By this apparatus the following advantages are secured: The water at its lowest.
temperature is first heated in the receiving tank and brought to such a heat that when
it is subsequently further heated in the coils of the heater, the sweating of these coils
is obviated, and hence the effect of exterior oxidation and encrustration are prevented,
and these coils may he used for a much greater length of time than is possible
with the common form of such apparatus, with the corresponding saving in cost
of repairs, cost of cleaning mechanism for such coil and time and trouble in the
care of the same.
It is possible that the receiving tank may be somewhat subjected to the effects
of exterior sweating and consequent deterioration, but it is to be noted that this
tank is constructed with special reference to being readily repaired. That is, the
tubes of this tank, being the parts where ruptures usually occur, are very easily
taken out and quickly replaced, as compared with the difficulty and time necessary
to replace a ruptured pipe of the heater. If, however, this tank be properly
constructed and related to the heater and to the working demands of the boilers, the
necessity for repair of the same may be to a very considerable extent obviated,
so far as concerns that due to the effects of sweating and exterior encrustations.
This tank and the heating coils form an operable combination that is a great
improvement upon any form of apparatus used at the present time for similar
purposes, that is, the supply pipe to the boilers may lead to them directly from
the heater; but it is preferred to use the supply reservoir to assist in keeping the
heating coils at a sufficiently high or uniform temperature to protect them against
the deteriorating effects explained. Thus, the reservoir may serve to hold a quantity
of heated water greater than is likely to be demanded by the boilers at any one time,
and thereby wholly obviate or reduce even the slight undesirable effects upon the coils
that might but for the presence of this reservoir, be due to a sudden demand by the
boilers. This reservoir also serves to preserve a more constant current or flow of
water through the heater than would be the case were the heater used without it
and this is essential to the life of the heater coils, as thereby any encrusting of or
deposits upon the inner surfaces of the coils thereof is prevented, so too, the reservoir
acts to collect the mud and lime and other impurities carried over by the water and
not deposited in the receiving tank.
As a further assistance to the regular action of the apparatus, the supply pipe from
this reservoir is continued into a vapor pipe that passes back to the supply tank. This
vapor pipe serves to conduct the vapor that may be formed over to the supply tank
where it is utilized to heat the cold water. Excessive pressure is also prevented by
the use of this pipe; the pressure in the apparatus being thereby kept uniformly at
the desired point, which obviously will be that represented by the head or pressure of
the source of supply, this head will of course vary according as the boilers are of a
high or low pressure type.
have described a water supply tank provided with automatic connections for
filling the same, as the form of supply that I prefer; but any similarly governed
source of water supply will serve the same purpose though not so well. That is, water
might be taken directly from the water mains or from a pump, though with this
arrangement the vapor pipe could not be so readily employed to partly heat the water
before it enters the receiving tank. Furthermore, this form of supply tank can be
advantageously used to heat such a quantity of water that the temperature thereof
shall not lower materially from the close of one day's work io the beginning of
another day's work, thus providing that a supply of warm feed water shall be ready
for use each time the boilers are filled up for work. It is also my design, when
practicable, to conduct the local exhaust steam pipe or pipes inio or through this tank,
that the heat of the exhaust steam may also be utilized.

page_text: The receiving tank, the intermediate heater or coil and the supply reservoir may, in
some cases be of other forms than those herein described though it is believed that
these forms are best adapted to the results sought to be obtained. do not therefore
describe any modifications thereof, although my invention contemplates any form of
such apparatus by which the objects I have described will be accomplished substantially
as in the present apparatus.
1
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Feed Water Heating Apparatus for Steam Boilers
and the like.
I, LEVI HUSSEY, of New York, in the County of New York and State of New
York, United States of America 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 :-
The invention relates generally to that class of water heating apparatus which is
employed for supplying steam boilers and other large tanks, and it relates particularly
to such apparatus when constructed and designed for use in a steam boiler or other
flue to heat the feed water of the boiler, or for use in a similar passage or conduit of
gases of combustion for the purpose of heating water for large tanks of any kind.
The invention will be described as embodied in a feed-water heater for a steam boiler,
but it is to be understood that it is applicable to other like purposes, without material
change.
It is well known that when cold water is fed into the pipes of a feed-water heating
apparatus, as heretofore arranged in boiler flues, the variation of temperature between
the inner and outer surfaces of the heating parts will, within certain limits known
as the "dew point," produce sweating or condensation of moisture on the outer
surfaces and, such outer surfaces being exposed to the varying heat of the gases and
the waste products of condensation in the furnace flue, a rapid oxidation and encrusta-
tion takes place thereon and the parts are rapidly destroyed. Usually such heating
surfaces consist of coils or banks of pipes, this form of heater being usually necessary
in order to secure the greatest heating surface in the smallest space, it being desirable
to not greatly enlarge the flue; and the rapid eating away of such pipes and con-
sequent liability to explosion, together with the cost and inconvenience of replacement
of the parts, is a fault of the common form of heaters that it is of the greatest
importance to obviate.
A further objection to the common form of heaters is that, by reason of the
fluctuating temperature of the contained water and its irregular motion through the
pipes, deposits of lime mud and like impurities in the water are deposited within
the pipes and act to clog them and thereby seriously interfere with the working
capacity of the heater.
It is the object, therefore, of the present invention to construct a water heater and
arrange its various parts so that the water will be preliminarily heated beyond the
dew point or the point where sweating would occur, before it passes into the heater
or the bank of pipes where it is raised to its highest temperature, thereby preventing
the fluctuations of temperature in such pipes that produce exterior deterioration of
their surfaces, and also so that the motion of the water through such pipes will be
continuous and practically constant, thereby preventing deposits in these pipes and
consequent clogging thereof.

page_text: In the accompan
rawings
Figure 1 is a general elevation view of the main parts composing a feed water
heater, constructed and arranged on the plan of my invention.
Figure 2 is a section of the furnace flue and contained water heating apparatus,
part of such apparatus being also in partial section.
Referring to these views in detail, A, A, represent a bank or series of steamı
boilers, and B is the smoke flue which is common to the boilers and conducts the
products of combustion to the chimney. This flue is made of a sufficient size to
contain the apparatus located therein without interfering with the draught necessary
to the furnaces; and it may be the flue leading from a single or any number of
boilers, or it may be any suitable part of any similar passage for conducting away the
gases and products of combustion from any furnace or similar chamber of com-
bustion.
is the receiving tank of the feed water heating apparatus. It consists of a
cylindrical shell, the lower half of which is pierced from end to end by open heating
tubes D through which the gases of the flue B circulate. This receiver is connected
by a pipe E with the supply tank F, which is open at the top and provided with a
float G connected to the steam pump H in such a manner that as the water becomes
lowered in the tank the pump will be caused to operate and supply the receiver C
through the feed pipe E.
J is the water heating coil or heater. The bottom courses of this coil are
connected with the bottom of the receiving tank, and the arrangement of its
successive courses is such that the circulation of the water is upwardly from course
to course. This arrangement of the heating pipes is not, however, essential in
itself; any suitable arrangement of the pipes whereby a large heating surface is
secured in a small space will answer
K is the supply reservoir, that is, the reservoir from which the heated water is
taken to charge the boilers. This reservoir consists of a cylindrical shell K, the
heads of which are pierced with open heating tubes L reaching from one head to
the other and extending from the bottom to the top of reservoir. From the top of
the reservoir rises the outlet pipe M to which is joined the inlet pipe N running to
a pump by which the heated water is forced into the boilers, or any one of them.
The outlet pipe M. continues over as a vapour pipe P to and enters the supply tank F
to just beneath the surface of the water therein. Qis a blow-out pipe for this
reservoir, and R is a blow-out pipe for the tank (', by which these receptacles may be
cleared of whatever deposit collects in them.
0
These structures constitute the essential part of the feed water heating apparatus.
They will be built in size and working capacity to correspond with the work required
of them and the available heat of the flue in which they are placed. This balancing
of these parts, each to the others, and all to the boilers they are to serve, is important
to the economical working of the apparatus in the best way; but as these are matters
of engineering knowledge, it is not essential to enter upon a full explanation thereof
here. It may be noted, however, as one of the important features of construction,
that the receiving tank should be of such size that the water will not in ordinary
practice be drawn through it so rapidly as to enter the heating coils at a temperature
varying from a uniform or practically uniform temperature, which temperature, of
course, it is designed shall always be above that where sweating of the coils would
occur.
The operation is as follows: It is first to be understood that the heated gases of the
flue are circulating around and through the reservoir, the superheater and the receiving
tank, and thereby tending to raise the temperature of their contents. As the water
comes in at the top of the receiving tank it meets the heated water already there,
and, mingling with the same and passing around and between the tubes of this
receiver, it is brought to a temperature above the dew point for this apparatus as
it sinks to the bottom thereof. From the receiving tank the water passes to the
superheater, in which, by reason of the large beating surface thereof, it is brought to
the desired final temperature, that is, to very nearly boiling point. From the heating

page_text: coil the water passes into the bottom of the supply reservoir, where its temperature
is maintained, or slightly increased if desired, by circulating around the tubes of this
reservoir and mingling with the contents thereof as it ascends to the outlet pipe, from
which it is drawn and forced into the boilers in a condition at or just below the point
of vaporization.
By this apparatus the following advantages are secured: The water at its lowest
temperature is first heated in the receiving tank and brought to such a heat that when
it is subsequently further heated in the coils of the heater, the sweating of these coils
is obviated, and hence the effect of exterior oxidation and encrustation are prevented,
and these coils may be used for a much greater length of time than is possible with
the common form of such apparatus, with the corresponding saving in cost of repairs,
cost of cleaning mechanism for such coil, and time and trouble in the care of the same.
It is possible that the receiving tank may be somewhat subjected to the effects of
exterior sweating and consequent deterioration, but it is to be noted that this tank is
constructed with special reference to being readily repaired. That is, the tubes of
this tank, being the parts where ruptures usually occur, are very easily taken out and
quickly replaced, as compared with the difficulty and time nocessary to replace a
ruptured pipe of the heater. If, however, this tank be properly constructed and
related to the heater and to the working demands of the boilers, the necessity for repair
of the same may be to a very considerable extent obviated, so far as concerns that due
to the effects of sweating and exterior encrustations.
This tank and the heating coils form an operable combination that is a great
improvement upon any form of apparatus used at the present time for similar purposes.
That is, the supply pipe to the boilers may lead to them directly from the heater; but
it is preferred to use the supply reservoir to assist in keeping the heating coils at a
sufficiently high or uniform temperature to protect them against the deteriorating
effects explained. Thus, the reservoir may serve to hold a quantity of heated water
greater than
likely to be demanded by the boilers at any one time, and thereby
wholly obviate or reduce even the slight undesirable effects upon the coils that might,
but for the presence of this reservoir, be due to a sudden demand by the boilers.
This reservoir also serves to preserve a more constant current or flow of water through
the heater than would be the case were the heater used without it and this is essential
to the life of the heater coils, as thereby any encrusting of or deposits upon the inner
surfaces of the coils thereof is prevented. So, too, the reservoir acts to collect the
mud and lime and other impurities carried over by the water and not deposited in
the receiving tank.
As a further assistance to the regular action of the apparatus, the supply pipe from
this reservoir is continued into a vapour pipe that passes back to the supply tank.
This vapour pipe serves to conduct the vapour that may be formed over to the supply
tank where it is utilized to heat the cold water. Excessive pressure is also prevented
by the use of this pipe, the pressure in the apparatus being thereby kept uniformly at
the desired point, which obviously will be that represented by the head or pressure of
the source of supply. This head will of course vary according as the boilers are of a
high or low pressure type.
I have shown a water supply tank provided with automatic connections for filling
the same, as the form of supply that I prefer ; but any similarly governed source of
water supply will serve the same purpose though not so well. That is, water night
be taken directly from the water mains or from a pump, though with this arrangement
the vapour pipe could not be so readily employed to partly heat the water before it
enters the receiving tank. Furthermore, this form of supply tank can be advan-
tageously used to heat such a quantity of water that the temperature thereof shall not
lower materially from the close of one day's work to the beginning of another day's
work, thus providing that a supply of warm feed water shall be ready for use each
time the boilers are filled up for work. It is also my design, when practicable, to
conduct the local exhaust steam pipe or pipes into or through this tank, that the heat
of the exhaust steam may also be utilized.

page_text: The receiving tank, the intermediate heater or coil and the supply reservoir may, in
some cases be of other forms than those here shown, though it is believed that these
forms are best adapted to the results sought to be obtained. I do not therefore
illustrate and designate any modifications thereof, although my invention contemplates
any form of such apparatus by which the objects I have described will be accomplished
substantially as in the present apparatus.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is --
First. In a feed-water heating apparatus, the combination with a heating coil, of a
water heating tank located between the source of water supply and the said coil,
whereby the water is preliminarily heated before entering the coil, for the purpose set
forth.
Second. In a feed-water heating apparatus, the combination of a heating coil, a
water heating tank located between the source of water supply and the said coil, and
a hot water supply reservoir located between the coil and the boiler inlet, arranged
substantially as and for the purpose set forth.
Third. In a feed-water heating apparatus, the combination of a heating coil, a
water receiving and heating tank located between the source of water supply and the
said coil, and a supply tank located above said receiving tank and provided with
automatic water supplying connections, as and for the purpose set forth.
Fourth. In a feed-water heating apparatus, the combination with a heating coil
arranged between the tank for receiving the water and preliminarily heating it and a
reservoir for containing the heated water, a water supply tank connected with said
receiving tank, and a vapour pipe directly connecting the hot water reservoir with the
water supply tank.
Fifth. In combination, the flue B, the receiving tank C, coil J, and reservoir K.
Sixth. In combination, the flue B, the receiving tank C, the coil J, the reservoir K,
the water supply tank G, and the vapour pipe M, P.
Dated this 20th day of April 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.