IMPROVEMENTS IN STEAM BOILERS
Year: 1879

page_text: LETTERS PATENT to Alexander Melville Clark, of Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of." IMPROVEMENTS IN
STEAM BOILERS." A communication from abroad by Guy Daniel Daly, of
Flatbush, in the County of Kings, State of New York, United States of
America.
Sealed the 5th August 1879, and dated the 28th February 1879.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 28th February 1879.
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN STEAM BOILERS." [A communication from
abroad by Guy Daniel Daly, of Flatbush, in the County of Kings, State of New
York, United States of America.]
The object of this Invention is to provide a steam boiler of superior economy and
efficiency, cheap and simple in construction, easy to repair, economical of fuel, quick
to generate steam, and possessing elements of safety lacking in other boilers.
The boiler is of that type called a fire box boiler, and is to be set in an upright
position.
Within the shell are contained the ashpit, the fire chamber which extends upward
from the grate surface to the crown sheet, the water space or boiler proper above
the crown sheet, surmounted by the steain dome.
A special object of this Invention is to provide unusual facilities for the circulation
of the water and a maximum amount of heating surface, and these points are
secured as follows:-
The feed water is forced into the boiler by pump or otherwise, and after it has
attained a certain depth over the crown sheet the excess flows down through stop
cocks or valves above the crown sheet into pipes or tubes that lead down through
the crown sheet and in the forin of coils or zig zags partially fill the fire chamber
and thence lead out through the side of the fire chamber and terminate outside in
cocks or valves through which the water passes into tubes or pipes ascending
outside the boiler, by which it is returned to the water space above the crown
sheet. These outsido pipes should be jacketed to prevent condensation and loss of
heat.
In practice two or more systems of zig zag pipes are used in the boiler.

page_text: The cocks or valves above the crown sheet are so arranged and constructed that
while the water from above may flow through them into the zig zag tubes upward
pressure from the tubes at once closes them, or rather they remain open so long as
the pressure in the water spaces above the crown sheet exceeds in any degree the
pressure in the tubes, and close instantly that the pressures are reversed. And so
also of the cocks or valves on the outside pipes an excess of pressure in the zig zag
tubes or coils over that in the water space above the crown sheet or in the outside
pipes keeps them open for the outward and upward return flow of the water, while
a reverse pressure closes them at once.
When the boiler is in operation it is found that a very slight excess of pressure
in the water space keeps the first mentioned cocks open and the last mentioned
closed, and the zig zag tubes filled with water and steam until the action of the
surrounding flames so increases the pressure therein as to overbalance that in the
water space, close the first mentioned cocks against further delivery of water, and
open the last mentioned cocks for relief.
The pressure in the zig zag tubes or cocks being thus reduced, water again flows
into them from the water space above the crown shect to have its temperature
increased and to be ejected in the same way, and thus the circulation, the action
and re-action, continues so long as the fires are kept up.
I am well aware that without the valves this arrangement of tubes in connection
with the water space would be of doubtful utility if not altogether useless and
dangerous, especially if very hot fires were maintained, for with even pressure
throughout the tubes and water space the circulation which would always be
sluggish would become more feeble with increase of temperature until the point
might easily be reached where the repelled action of the hot tubes would expel all
water from sections thereof and expose them to quick destruction.
The arrangement herein described on the contrary compels a free circulation that
must increase with each increment of heat.
To decrease the commotion caused by the return of the water and steam from the
zig zag tubes or coils to the water space, the outside return tubes which enter the
water space near the top are bent down to within a few inches of the crown
sheet.
It is obvious that upon the size of the tubes will depend the extent of heating
surface, and the extent of the sub-division of the volume of water exposed to the
heat, and that smaller tubes can be used advantageously in this construction of
boiler than could be practicable in any other.
In order to secure, as is sometimes desirable, arbitrary control of the action in
order at will to increase the friction, the inertia of the valves, rods, or levers are
permanently attached to them, and by these means too the cocks of any one system
of tubes may, in case of the rupture or leakage of the tube, at any moment be
firmly closed and the work of the boiler continued with the remaining system or
systems, and as the tube coils or zig-zags are generally constructed in sections it is
evident that repairs can be most easily and expeditiously made.
The crown sheet of the boiler being so far removed from the fire is less liable to
deterioration and injury than is the case in ordinary boilers.
The extent and disposition of the heating surface assumes great economy of fuel,
and the rapid circulation in the tubes will keep them free from sediment.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
14th August 1879.
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN STEAM BOILERS." A communication from
abroad by Guy Daniel Daly, of Flatbush, in the County of Kings, State of New
York, United States of America.
The object of this Invention is to provide a steam boiler of superior economy
and efficiency, cheap and simple in construction, easy to repair, economical of fuel,
quick to generate steam, and possessing elements of safety lacking in other
boilera.
The Invention is illustrated in the accompanying Drawing, Figure 1 of which
represents a sectional elevation of the boiler, and Figure 2 a horizontal section on
line x-x.
Similar letters of reference indicate corresponding parts in the two
Figures.
The boiler is of that type called a fire box boiler, and is to be set in an upright
position. Within the shell are contained the ash pit A, the fire chamber B which
extends upward from the grate surface a³ to the crown sheet b¹, the water space or
boiler proper C, and the steam dome D.
A special object of this Invention is to provide unusual facilities for the circulation
of the water and a maximum amount of heating surface, and these points are secured
as follows:-The feed water is forced into the boiler by a pump or otherwise through
the feed pipe E, and after it has attained a certain depth over the crown sheet the
excess flows down through the stop cocks or valves F, F, into the coils or zigzag
pipes or tubes G, G, which partially fill the fire chamber, and thence out through
the cocks or valves H, H, into the tubes or pipes I, I, by which it is returned to
the water space C.
The pipes I, I, should be jacketted to prevent condensation and loss of heat. In
the Drawing but one pipe system is shown complete, but in practice two or more
systems are used, and the cocks H, H, are ordinarily arranged on a horizontal rather
than on a vertical line as shown. The cocks F, F, are so arranged and constructed
that while the water from above may flow through them into the zig-zag tubes G, G,
upward pressure from the tubes at once closes them, or rather they remain open so
long as the pressure in C exceeds in any degree the pressure in the tubes, and close
instantly that the pressures are reversed. And so also of the cocks H, H, an excess
of pressure in the tubes G, G, over that in C or I, I, keeps them open for the
outward and upward flow of the water, while a reverse pressure closes them at
once.
When the boiler is in operation it is found that a very slight excess of pressure
in C keeps the cocks F, F, open and H, H, closed, and the tubes or coils G, G, filled
with water and steam until the action of the surrounding fames so increases the
pressure therein as to overbalance that in C, close F, F, against further delivery of
water, and open H, H, for relief.
The pressure in the tubes or coils C, G, being thus reduced, water again flows
into them through cocks F, F, to have its temperature increased and to be ejected
in the same way, and thus the circulation, the action, and reaction, are continuous
so long as the fires are kept up.
I am well aware that without the valves this arrangement of tubes in connection
with the water space would be of doubtful utility if not altogether useless and
dangerous, especially if very hot fires were maintained, for with even pressure
throughout the tubes and water space the circulation which would always be
sluggish would become more feeble with increase of temperature until the point
might easily be reached where the repellent action of the hot tubes would expel all
water from sections thereof and expose them to quick destruction.

page_text: The arrangement herein shown on the contrary compels a free circulation that
must increase with each increment of heat.
To decrease the commotion caused by the return of the water and steam from
tubes or coils G, G, to the water space C, I bend the tubes I, I, down to within a
few inches of the crown sheet. It is obvious that upon the size of the tubes will
depend the extent of heating surface and the extent of the subdivision of the volume
.of water exposed to the heat, and that smaller tubes can be used advantageously
in this construction of boiler than could be practicable in any other.
In order to secure, as is sometimes desirable, arbitrary control of the action in
order at will to increase the friction, the inertia of the valves F, F, and H, H, rods
or levers are permanently attached to them, and by these means too the cocks of
any one system of tubes may in case of the rupture or leakage of the tube at any
moment be firmly closed and the work of the boiler continued with the remaining
system or systems, and as the tube coils or zig zags are generally constructed in
sections it is evident that repairs can be more easily and expeditiously made.
The crown sheet of the boiler being so far removed from the fire is less liable to
deterioration and injury than is the case in ordinary boilers.
The extent and disposition of the heating surface ensures great economy of fuel,
and the rapid circulation in the tubes will keep them free from sediment.
The above are a few of the advantages claimed for this construction of boiler.
Having described the nature of the said Invention and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
hereinbefore in part recited Lotters Patent is,-
1st. In the construction of a steam boiler the combination of the fire chamber B,
water space C, cocks F, F, tubes G, G, cocks H, H, and tubes I, I, substantially as
herein shown and described.
2nd. Constructing a steam boiler with tubes G, G, placed in the fire chamber and
extending up through the crown sheet of the boiler, and having on their upper ends
cocks F, F, and on their lower ends cocks H, H, substantially as and for the purpose
described.
3rd. In connection with the water space of a steam boiler one or more circulating
systems, each consisting of cock F, tube G, cock H, and tube I, constructed and
arranged substantially as herein shown and described.
4th. The method of arbitrarily controlling the action of the valves of the cocks F, F,
and H, H, substantially as and for the purposes described.
5th. A steam boiler having within its fire chamber water tubes communicating at
one end with the water chamber and at the other with tubes outside of the boiler
that themselves connect with the water chamber, substantially as herein shown
and described.
6th. A steam boiler having water tubes in the firo chamber in which the water
circulation is controlled by the automatic action of valves, substantially as herein
shown and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my band and seal, this Thirteenth day of August, in the year of our Lord
One thousand eight hundred and seventy nine.