New or Improved Arrangement of Apparatus for Heating Feed- water by Utilizing the Waste Heat in Steam-generator Flues.
Year: 1889

page_text: Date of Application, 3rd Dec., 1889.
Complete Specification Left, 3rd Sept., 1890-Accepted, 4th Oct., 1890
PROVISIONAL SPECIFICATION.
New or Improved Arrangement of Apparatus for Heating Feed-
water by Utilizing the Waste Heat in Steam-generator Flues.
I JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this invention (which has been com-
municated to me from abroad by Joseph Alexis Damey of 16 Avenue Rapp Paris in
the Republic of France Engineer to be as follows:—
This invention relates to an improved construction and arrangement of apparatus
for heating or superheating feed water for steam generators by means of a series of
tubes utilizing the heat in the flues as hereinafter explained.
Apparatus for heating feed water for steam generators being arranged in the frame
or bed plate of the engine or otherwise are well known but the apparatus forming
the object of the present invention may be employed with advantage as a superheater
of water which being heated to a certain extent by the exhaust steam in the first
place afterwards flows through a series of superheating tubes heated by the latent
heat in the double and triple return flues of the generators arranged as hereinafter
described.
The fire giving out part of its heat in the internal furnace or firebox the flame
afterwards passes through the internal tubes of the generator to the smoke box where
a partition or division compels the flame to pass-through two openings at each side into
lateral return flues communicating at the front of the generator with other flues
leading the products of combustion back to the upper part of the smoke box whence
they finally escape into the chimney.
It results that the flame or heat circulates three times first in the interior and
afterwards in the two sides of the generator before reaching the chimney and all the
superheating tubes being placed in the flues are surrounded by this latent heat from
the first to the last so that the water passes into the generator at the temperature of
ebullition.
The cold water being drawn by the feed pump from the tank of the condenser first
passes through two tubes heated by the exhaust which are arranged in the bed plate
or foundation of the engine and after thus having its temperature raised to a certain
extent passes in succession through all the superheating tubes beginning at the
uppermost tube on each side and after passing through all the tubes in succession
enters the generator in a boiling condition through the retaining valves.
The feed pump is so arranged that the water can be confined to the tubes on one
side only in case of a leakage.
The connections of the tubes are formed by elbow or U shaped junction pieces
secured in position by a strap or stirrup shaped piece engaging with flanges or pro-
jections on the tubes. There may be 23 or other convenient number of tubes on
each side of the generator.
The arrangement of successive multiple superheating tubes in certain cases may be
provided with a metal casing with nonconducting cement interposed on galvanized
wire gauze.
In the case of stationary boilers the flues are of brick work arranged for a triple
passage of flame. The series of superheating tubes may be arranged at the sides of the
upper flues only.
With 22 tubes of 2 inches external diameter and about 12 feet in length for
example a large area of heating surface can be obtained so that the feed water is
already boiling when it enters the boiler. Any convenient number of tubes may be
employed and the tubes may be placed either in one or both of the lateral flues.
The following are the chief advantages of the invention.

page_text: 1. The feed water is raised to the highest temperature possible by utilizing to the
best advantage heat which would otherwise be wasted in the flues.
2. Economy of construction-the brickwork flues being less costly than the
ordinary casing of non heat conducting or fire proof cement enclosed in a metallic
covering.
3. The heat is more concentrated than it is in the ordinary constructions.
11
בד
1
1000
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, Agents.
COMPLETE SPECIFICATION.
New or Improved Arrangement of Apparatus for Heating Feed-
water by Utilizing the Waste Heat in Steam-generator Flues.
1 JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this invention (which has been
communicated to me from abroad by Joseph Alexis Damey of 16 Avenue Rapp
Paris in the Republic of France, Engineer) 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 an improved construction and arrangement of apparatus
for heating or superheating feed water for steam generators by means of a series of
tubes utilising the heat in tho flues as hereinafter explained.
Apparatus for heating feed water for steam generators being arranged in the frame
or bed plate of the engine or otherwise are well known but the apparatus forming the
object of the present invention acts as a superheater of water which being heated to
a certain extent by the exhaust steam in the first place afterwards flows through a
series of superheating tubes heated by the latent heat in the return flues of the
generators arranged as hereinafter described.
And in order that the said invention may be fully understood I shall now proceed
more particularly to describe the same and for that purpose shall refer to the several
figures on the annexed sheets of drawings the same letters of reference, indicating
corresponding parts in all the figures.
Figure 1 of the accompanying drawing represents in side elevation partly in section
so much of a portable engine and boiler as is necessary to explain the invention and
Figure 2 illustrates the boiler flues in transverse section.
The fire gives out part of its heat in the internal furnace of firebox B of the boiler A
and the flame passes to the smoke box through the internal tubes of the generator
from C to D where a partition or division plate Y (shewn in dotted lines in Figure 2)
compels the flame and products of combustion to pass through two square openings K
at each side of the smoke box. The arrows (Figure 1) indicate the direction
which the flame is compelled to follow by means of a horizontal partition at M.
The products of combustion pass to the front of the boiler at L' and finally escape
into the chimney F through two openings N. O, Fig. 1, is an orifice for the supply
of air under pressure to improve the draught if required.
The flames or products of combustion circulate or flow from one end of the boiler
to the other three times first in the interior or inner flues or tubes and afterwards in
the two flues at the sides of the generator before reaching the chimney. A series of
superheating tubes V, (3 only of which are shown in Figure 1) being placed in the
side flues are acted on by the latent heat of the said flaine or products throughout
their entire length so that the feed water after circulating in the tubes V is heated to
ebullition by the time it reaches the check valves at a Figure 2 where it passes into
the generator A.
The cold feed water being drawn by the feed pump J from the tank or water space
of a condenser H which may be provided with an injector I and operate as described
in the Specification accompanying my application for Letters Patent dated

page_text: 4th December 1889 No. 19494 first passes through two tubes heated by the exhaust
which are arranged in the bed plate or supporting frame of the engine G and after
thus having its temperature raised to a certain extent is conducted by a pipe Z to the
series of super-heating tubes V beginning at the uppermost tube on each side and
after passing through all the tubes in succession enters the generator in a boiling
condition through the retaining valves a.
The feed pump is so arranged that the water can be confined to the tubes V on
any one side of the boiler in case of a leakage occurring in the tubes on the other
side.
The mode of connecting the ends of the tubes V is illustrated on a larger scale in
Figures 3 and 4. T is an elbow or U shaped junction piece secured in position by
means of screws U and bails or stirrup shaped pieces U engaging with the ends of
the tubes V. Any suitable number of these tubes may be employed. In the
example illustrated in Fig. 2 there are 23 of such tubes provided on each side of
the boiler.
The arrangement of successive multiple superheating tubes V may be employed
without the metal casing or jacket X Figure 2 which is constructed with non
conducting cement combined with galvanised wire gauze. E represents the steam
dome of the boiler which is supported either on axles R S or on supports PQ.
In the case of stationary boilers the flues are of brickwork arranged for a triple
passage of flame. The series of superheating tubes are arranged at the sides of the
upper flues. An example of a stationary boiler with superheating feed water tubes
according to this invention is illustrated in Figures 5 to 8. Figure 5 represents the
boiler and flues in longitudinal section on the line 1-2. Figure 7 and Figure 6
represents a horizontal section on the line 3-4 Figure 5. Figure 7 represents the
boiler in transverse section on the line 5-6. Figure 6 and Figure 8 illustrates the
smoke box end in elevation.
This generator may be provided with only six superheating tubes V there being
three of such tubes in the upper part of the flue on each side of the boiler as indicated
on the left hand side of Figure 7 being an arrangement corresponding to Figure 8
which is a view of the smoke box end of the boiler.
On the other or right hand side in Figure 7 is shown a more expensive but more
complete arrangement for superheating the feed water. This arrangement enables
the water to circulate in 11 tubes on each side of the boiler or 22 tubes in all. These
22 tubes are preferably of about inches (50mm) external diameter and about 12 feet
(46) in length producing together a large area of heating surface of about 19 square
yards (159) on a distance of about 334 feet (102 metres) so that the feed water is
boiling when it enters the boiler.
The following are the chief advantages attending the use of the invention.
1. The feed water is raised to the highest temperature possible by utilising
to the best advantage heat which would otherwise be wasted or radiated in the flues.
2. Economy of construction the brickwork flues being less costly than the ordinary
or jacketting casing of non heat conducting or fireproof cement enclosed in a metallic
covering.
3. The heat is more concentrated than it is in the ordinary constructions.
Having now particularly described and ascertained the nature of the said inven-
ion and in what manner the same is to be performed I declare that what I
laim is:
1. The arrangement of feed water heating or superheating apparatus in which feed
vater taken from the water chamber of the condenser is caused after passing through pipes
r tubes in the base of the engine heated by exhaust steam to circulate in longitudinal
arallel tubes arranged in flues at the sides of the cylindrical body of the boiler and
eated by the flames or products of combustion in the said flues so that the said water
nters the boiler through the check valves in a boiling condition substantially as
ereinbefore described.
2. Connecting the ends of the superheating tubes V in the flues by means of

page_text: Ushaped junction pieces pressed against the ends of the tubes by bails or stirrup
shaped pieces substantially as herein before described and illustrated in the accompanying
drawings.
3. In combination with feed water heating apparatus arranged as herein before
set forth the arrangement enabling the feed water to circulate in one only of the two
series of superheating tubes in case of leakage in the other series substantially as
hereinbefore described.
4. The combinations and arrangements of parts constituting the improvements in
apparatus for heating feed water for steam generators substantially as hereinbefore
described.
J. H. JOHNSON & Co.