Heating and Circulating Feed Water in Multitubular Boilers.
Year: 1886

page_text: COMPLEIE DIECIFICATION.
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Heating and Circulating Feed Water in Multitubular Boilers.
We, WILLIAM VOIT of Kupfergraben 4 II Berlin, Germany, Engineer, and WILLIAM
DAVIS HOOKER, of 512 Wash Street, in the City of St. Louis and State of
Missouri, United States of America, Engineer, do hereby declare the nature of
our invention for HEATING AND CIRCULATING FEED WATER IN MULTITUBULAR
BOILERS, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
Our invention relates to devices for heating and circulating feed water in
multitubular boilers and is designed more especially for use upon steam fire
engines, where lightness and compactness are essential.
Both the boiler and the heater are mounted in detachable framing by means of
which they or either of them may be taken off without disturbing the other parts
of the fire engine.
The heater is of the coil double cylindrical character and the water is passed
through the coils under pressure and exhaust steam is run through the cylinders in
a direction opposite to the flow of the water.
By means of the heater the water is brought to a suitable temperature before
entering the boiler so that no injurious effects are produced on the boiler by the
introduction of water at a low temperature, and no retardation in the production
of steam ensues. Consequently we can make the boiler much lighter and reduce
the consumption of coal or other fuel, while at the same time we are enabled to
speedily acquire and readily maintain the requisite steam pressure.
The water from the heater passes into the boiler and is circulated therein in a
manner to expedite the formation of steam.
The boiler is of the multitubular variety and is provided with a circulation
sheet lying between the boiler shell and fire box and extending over a portion of
the top of the fire box, with space all around between it and the shell and between
it and the fire box for the passage of. the water. A portion of the tubes extend
through the circulation sheet on top of the fire box, and a portion pass up through
the opening in the circulation sheet.
A circular pipe is placed above the circulation sheet and provided with nozzles.
of varying length which extend down between the circulation sheet and the boiler.
shell.

page_text: The water from the heater is introduced through this circular pipe and passes
out through the nozzles, down between the boiler shell and circulation sheet,
around the lower edge of the circulation sheet, up between the circulation sheet
and fire box, over the fire box and out into the body of water surrounding the
tubes through openings which will be hereinafter more particularly described,
becoming intensely heated in its travel, and liberating a great amount of steam
when it passes up among the tubes.
It will be understood that the water in both the heater and boiler is kept under
pressure by a feed water pump not shown in this application, but if desired the
heater and boiler may be supplied without this pressure.
The accompanying drawings illustrate what we consider the best means for
carrying the said invention into practice.
Figure 1, is a central vertical section of the boiler and a side elevation of the
heater.
Figure 2, is a vertical section of the heater cylinders taken at right angles to
Figure 1.
Figure 3, is a plan view of the top of the circulation sheet and adjacent parts of
the boiler.
Figure 4, is a detail view of the feed pipe and nozzles.
Figure 5, is an inverted view of one of the cylinder heads detached.
Figure 6, is a section across one of the heating cylinders at point where the
flange is connected to it.
Figure 7, is a longitudinal central section of one of the nozzles..
Similar letters of reference indicate corresponding parts in all the figures where
they occur.
A, A designate the detachable frame bolted together at a. Both the heater
and boiler are suspended in this frame. B is the boiler and C, C, are the cylinders
of the heater. These cylinders while light are of ample strength to resist any
pressure of exhaust steam from the engine. On the ends of the cylinders C, C, we
provide flanges c¹ screwed or otherwise tightly secured thereto. To these flanges
we bolt the heater heads C2, C3, which have stuffing boxes c*, c*, in their ends,
through which stuffing boxes pass the ends of the coils D, D. These packings or
stuffing boxes prevent the escape of exhaust steam at these points. The coils D, D,
rest at their lower ends on the heater heads, The coils are made of copper pipe
about one inch in outside diameter and are coiled tightly together. The diameter
of the enclosed space inside of each coil is about the same as that of the exhaust
pipe from the engine. When the coils are placed inside of the heater cylinders a
small annular space is left all around between the coils and the shell of the cylinders
by reason of the difference in diameters.
Each of the heads C2 have a hole c³ in the center the size of the opening in the
center of the coil, also a number of small holes around the central hole close to
the inner circumference of the heads. These openings & c afford means for the
exhaust steam to pass both inside and outside of the coil.
The two cylinders C, C, are connected at the bottom by a pipe c³ screwed tightly
in the heads. The exhaust steam enters through the top bead of one of the
cylinders, passes down said cylinder then across through pipe co and up the other
cylinder and out through the head whence it is conveyed by the exhaust pipe c
to the boiler where the variable exhaust nozzle is placed to produce the back
pressure for the purpose of creating the draft for the combustion of the fuel. As
the use of this variable exhaust nozzle is very common and well understood we
have not deemed it necessary to illustrate it.
The ends of the coils D, Ď, above the heater are connected together by a pipe d;
and the ends below have pipe nipples or connections d, d, which are both con-
nected to the main feed pipe D¹ which leads from the boiler feed pump not shown.
A stop cock d✶ is placed in each of the pipe nipples d¹, d', at the bottom near
each cylinder, and a stop cock D* between the points where the nipples d¹, d, con-
nect with the feed pipe D¹. This center cock D* being closed and the two side

page_text: cocks d*, d*,.opened the water from the feed pump will go up in the coil in the
cylinder to the left hand as shown in Figure 2, and pass through the pipe & across
to the right hand cylinder and descend through the coil in said cylinder and pass
into pipe D¹ back of cock D* and be carried up into the boiler through feed
pipe D
The exhaust steam enters through the exhaust pipe into the right hand
cylinder as shown in Figure 2, and descends through it, crosses over to left hand
cylinder through pipe c, ascends through said left hand cylinder and passes out
through pipe c, thus thoroughly and satisfactorily heating the water in the coils
by passing both inside and outside of said coils as above described.
"
Should the pipes of the coils burst or the heater fail for any other reason, it
is evident from the construction shown and from the manner in which the
cocks D, d*, d*, are disposed that the water can be run directly from the pump
into the boiler by closing the side cocks d*, d*, and opening the center cock D*,
and the engine continue in action.
Flanges E are riveted or otherwise secured to the sides of the cylinders C, C, as
shown and are bolted to a portion A* of the detachable framing. The portion A*
is detachably secured to portion A by bolts as shown at .a. If any repairs are
needed or any inspection desired, either of the heater, boiler or engine the parts of
the framing may be separated by removing the bolts and then by disconnecting
the steam and water pipes, the parts may be removed without interfering with
any other part.
When it is desired to remove only the heater it can be done by simply removing
the bolts which connect the flanges E with the framing A*.
In the boiler G is the outer shell and H the fire box shell secured to the shell G
at the base and provided with lugs p, p, at proper height on which the grate. rests.
I is a circulating sheet secured between shells G and H by bolts o which extend
through all three parts G, H, and I, and hold the sheet I about midway between
the shells G and H, or perhaps a little nearer to shell. H than to shell G. A circu-
lating space is thus provided between shell G and sheet I.for the descent of the
feed water, and a space between sheet I and shell H for the ascent of the same,
the sheet I having its lower edge raised a suitable. distance above the bottom of
the water chamber.
Secured at a suitable distance above space il by. lugs ; connected with the outer
shell G is the circular feed pipe J to which the feed pipe D' from the heater
connects. This pipe J may extend entirely around the boiler or only partially
round, in which latter case the ends will be suitably capped or sealed.
In the under side of the pipe J are screwed the nozzles J* which project down
into the space . In the shell G opposite each nozzle J* is placed a removable
plug G. When this plug is removed a pair of tongs may be inserted through the
opening to remove the nozzle for cleaning, repair &c. The nozzles J* may have a
bore of any capacity desired and upon the size of this bore and velocity of the
pump by which the water is supplied depends the degree of force given to the
circulation.
The construction of the upper portion of the boiler is that commonly followed.
The bottom of the smoke box forms the upper tube sheet K and the top of the
fire box forms the lower tube sheet L in which sheets are secured in any ordinary
or suitable manner a group or set of tubes M of any desired number, size and
proximity to each other.
The circulating sheet I is extended up over the lower tube sheet L (the top of
the fire box) and is carried inward towards the center as shown leaving an opening
or central hole Z equal in diameter to about one third of the diameter of the tube
sheet L. This horizontal extension is marked I* and its purpose is to carry the
water well inward towards the center of the group of tubes before releasing it; and
when thus released it will be dispersed or thrown outward towards the sides of the
boiler and again descend to travel round the circulation sheet as before, freeing
itself of a vast amount of steam in this rapid and thorough circulation.

page_text: The tubes M pass through the extension 1* of the circulating sheet in holes or
openings somewhat larger in diameter than the tubes themselves, leaving a small
annular space or opening around each tube embraced by the extension I*, through
which openings a small. quantity of the rising water escapes and passes upward
around the tubes M, to receive a still more intense degree of heat and throw off a
greater quantity of steam.
It will be understood that the water when allowed to circulate naturally will
follow the same path as that occasioned by the force feed, above described, and it
will be understood that the force feed may be omitted and the natural circulation
relied upon. But for fire engine purposes a powerful circulation is required and it
will be found advantageous to retain the force feed.
The nozzles J* are made of varying lengths as shown, some of them preferably
extending to the bottom of the circulation sheet and turning up in the space
between it and the fire box. The nozzles are preferably bored out in the form of
a contracted vein so as to discharge the feed water forcibly. But we do not claim
this form of nozzle as they are old in hose pipes.
The circular feed pipe will be located far enough above the top of the circulation
sheet so as not to obstruct the descent of the return currents between the circulation
sheet and the boiler shell.
The extension I* of the circulation sheet may be omitted. The tubes M may fit
tight in the openings in the extension without the annular discharge openings
around them. The size of the center opening Z in the extension I* may be
varied. The plugs G* may be omitted and the shell G made solid.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1-In a steam boiler. of the kind described the combination with the boiler and
fire box shells and interposed circulating sheet of a force feed for the water
arranged above the space between the boiler shell and circulating sheet to project
the water downward into, said space, as set forth.
2-In a steam boiler the combination with the boiler and fire box shells and an
interposed circulating sheet, of an annular force feed pipe, extending partially or
entirely around the boiler and provided with nozzles projecting down into the
space between the boiler shell and circulating sheet, as set forth.
3-In a steam boiler the combination with the boiler and fire box shells and
interposed circulating sheet, of the force feed pipe extending partially or entirely
around the boiler and provided with nozzles projecting down into the space
between the boiler shell and circulating sheet and a plug in the shell of the boiler
opposite each nozzle, as and for the purpose set forth.
4 In a steam boiler the combination with fire box and boiler shell of the
circulating sheet extending over the top of the fire box and provided with the
central opening or hole as described.
5 In a steam boiler the combination with the fire box, tubes and boiler shell of
the circulating sheet as described extending partially over the top of the fire box
and provided with openings through which the tubes pass, a little larger in
diameter than the tubes, as and for the purpose set forth.
6-In a steam boiler the combination with the fire box, boiler shell and circu-
lating sheet of the feed pipe having, nozzles of differing lengths extending down
between the boiler shell and the circulating sheet as set forth.
7-In a steam boiler the combination with the fire box, boiler shell and circu-
lating sheet as described, of a feed pipe having nozzles extending down between
the boiler shell and circulating sheet one or more of which nozzles extend below
the said sheet and slightly turn up to throw the water around it, as set forth.
8-In a steam boiler the combination with the fire box, boiler shell and circu-
lating sheet, of the feed pipe having nozzles made or bored in the form of a
contracted vein and having a still further contracted' discharge opening.

page_text: 9 In a portable.steam fire engine mounted on wheels for rapid transit the
framing carried on the after running gear in which the boiler is fastened in com-
bination with a separate framing carried on the forward running gear in which is
secured the heater and working machinery of the fire engine, said fraining being
adapted to be separated and connected without removing any parts attached to
either section of the framing.
10-A heater formed of one or more cylinders through which the water is led in
pipes having a central opening in its head and several sinaller openings around said.
central opening for the admission of the heating fluid or medium as set forth.
11-A heater for feed water consisting of one or more cylinders having the
water pipe coiled within them and having a central space in said coil and a small
annular space around said coil and openings in the head of said cylinder to permit
the heating medium to enter both of said passages as set forth.
12-A heater consisting of one or more cylinders having the water pipes coiled
therein in the manner set forth and heads upon said cylinders having stuffing
boxes through which the water pipes pass, said heads being also provided with
openings as described for the admission of steam to both the interior and exterior
circumferences of the coils, as and for the purpose set forth.
13 A heater consisting of a pair of cylinders or tubes connected at the top to
the exhaust pipes from the engine and boiler respectively and having a coupling or
connecting pipe uniting them at the bottom and the water pipes coiled in said
cylinders as set forth.
14 A heater having the two cylinders as described and the water pipes coiled
therein in combination with the main feed water pipe and nipples connecting the
ends of the coils with said pipe, a cock in said main pipe between the points where
the nipples are joined to it and a cock in each nipple, substantially as and for the
purpose set forth.