IMPROVEMENTS IN FURNACES OR FIRE-PLACES, AND IN APPARATUS TO BE USED IN CONNECTION THEREWITH
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the Office
of the Commissioners of Patents, with his Petition, on the 26th March
1863. A communication from abroad by Louis Hébert, of Paris, in tho
Empire of France, Engineer.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN FURNACES OR FIRE-PLACES, AND IN APPARATUS TO BE USED
IN CONNECTION THEREWITH," a communication from abroad by Louis Ilébert, of
Paris, in the Empire of France, Engineer, to be as follows:-
This Invention has for its object the obtaining of a better and more perfect
combustion of small or inferior coal or fuel in steam boiler and other furnaces
or fire-places, and consists chiefly of a peculiar arrangement of apparatus to be
adapted beneath the grates or fire-holding portions of furnaces or fire-places,
whereby an increased supply of air is directed into the burning fuel by the aid
of a number of steam jets. This same apparatus placed above or beyond the
furnace in the smoke stack or flue will also operate as a powerful exhauster or
draught producer, whereby the tall chimneys or long flues bitherto required to
produce the desired draught are rendered unnecessary.
The apparatus above referred to, and which the Inventor calls a "hydrofère,"
consists of a tube, which is passed through a door or plate fitted to the front
of the ash-pit. This tube is either placed at an angle on this door or plate so
as to cause the induced air and steam jets to pass directly upwards against the
entire under surface of the grate from the edge of the dead plate to the back
of the grate bars, or that part of the tube which is outside the door or plato

page_text: may be placed in a horizontal or vertical position, in which case the end of
the tube inside the ash-pit is provided with a bend turning upwards towards
the grate. At the lower or outer end of this tube and in the interior of the
same there is fitted, by means of internal cross bars, a steam pipe of an annular
form, having a straight pipe passing diametrically across it. A number of
small steam jet apertures are made on the surface of these pipes next the
grate, and corresponding apertures of larger diameter and closed by screw
plugs are made on the opposite side of the pipes, with a view to facilitating
the cleaning of the interior of the pipes and jet holes. A steam pipe leading
from a steam generator is coupled with the jet pipes inside the tube, and it
passes off horizontally at right angles, and then rises vertically on its way to
the generator; this vertical portion of the pipe coinciding with the axis of the
hinges of the ash-pit door. At this part any ordinary steam cock is provided,
which is either made to open and shut by hand or by the mere act of closing
and opening the ash-pit door. The cock is fitted to the side of the fire-door
frame, and may be made with a fixed or stationary hollow plug, the rotatory
motion to open and shut the cock being imparted to the body of the cock in
lieu of to the plug itself. Other cocks are also provided for regulating the force
of the jets and for shutting off the steam entirely from the boiler in case of
repairs being required. On turning on the steam jets in the tube, a vacuum
will be formed therein, and the atmospheric air will be drawn in and impelled
forward by the steam jets (with which it mingles), with a velocity in accord-
ance with the pressure of the steam, the air and steam being directed against
and between the grate bars. In traversing the grate the steam becomes
decomposed into its constituents, oxygen and bydrogen, which by their
pressure greatly increase the heat of the furnace, and thus afford facility for
the burning of fuel of a small and inferior description. The grato bars should
be very thin and have very narrow spaces between them. The head or pro-
jection of the bars is formed on one side only, and in order to prevent the bars
from twisting or warping, a number of studs or projections should be formed
on the same side as the head, so that the several bars will support each other
laterally throughout their length without impeding the passage of the air and
steam between them. One, two, or more of these jet tubes or "hydrofères"
may be fitted to a single furnace or fire-grate, according to the size of grate
and draught required.
For beating or welding furnaces the best proportions for the fire-bars are
2 inches width of head and 33 inches in height, leaving a projection of inch
below to hook on to the bearers, so as to maintain the bars in their places.
The thickness of the head should be about 1 inches, that of the top of the bar

page_text: 8th inch, and the thickness of the bottom, the depth of the bar about 24
inches. In front of this grate there is a sliding door, which is readily opened
when the pecker or poke is to be introduced. By placing a jet tube in the fluo
beyond the furnace, the draught is considerably augmented, and facility is
afforded for the effective utilization of the waste gases from blast furnaces for
the purpose of generating steam, whilst the necessity for long flues or tall
chimneys is obviated.
In applying this Invention to puddling furnaces it is found that the length
of the flame is greatly increased by reason of the jets of steam and air, and
consequently a second hearth may be formed between the ordinary puddling
hearth and that portion of the furnace where the metal is heated, preparatory
to being placed on the puddling hearth. By the use of the second hearth the
yield of the furnace is considerably increased without increasing the con-
sumption of fuel. The use of the jet tube in smiths' forges enables their
construction to be improved, as the flame can be carried into a separato
heating chamber, formed by placing a moveable arch or top over the hearth;
the articles to bo heated are placed in this chamber, and are out of contact
with tho fuel itself.
In locomotive boiler furnaces the tube of the injector may be placed hori-
zontally outside the ash-pit, whilst in marine boiler furnaces it may assume a
vertical position; but in both cases the end or ends of the tube or tubes is or
are provided with a bend to direct the jets upwards against the grate.
The injecting apparatus herein-before described is applicable to the furnaces
of brick, pottery, and other kilns, and to every description of furnace where
grate bars or equivalent means are employed for supporting the fuel.