IMPROVEMENTS IN FURNACES
Year: 1879

page_text: LETTERS PATENT to James Dodge, of the Atlantic Works, Newton Heath,
near Manchester, Engineer, for the Invention of "IMPROVEMENTS IN FURNACES."
PROVISIONAL SPECIFICATION left by the said James Dodge at the Office of
the Commissioners of Patents on the 25th November 1879.
JAMES DODGE, of the Atlantic Works, Newton Heath, near Manchester, Engineer.
"IMPROVEMENTS IN FURNACES."
This Invention is applicable to furnaces for melting metal in crucibles, and
consists, firstly, in making the casing, which may be of iron or other suitable
material, in parts or sections, so that it may be removed from that part of the clay
lining which is burnt or injured by the fire without disturbing that part of the
lining which is uninjured.
Another part of this Invention consists in making the furnaces in duplicate or
nearly so, and arranging them in such a manner that when fuel is burnt in one of
the furnaces the flame will also pass through the other, thus heating the crucibles
in the second furnace; the metal in the furnace in which the fuel is burnt is
melted and it can be removed, and the crucibles in the second furnace that has not
received fuel can be placed in the first furnace, or fuel can be placed in the second
furnace without removing the crucibles, and the flame will be caused to pass from
the second to the first furnace in which fresh metal has been placed.
In some cases the crucibles may be dispensed with, and the metal may be heated
by the direct action of the flames.
Another part of this Invention consists in so arranging the frame on which the
grate bars rest that it can be caused to rotate, carrying the bars and the crucibles
which rest upon them with it, and thus bring each crucible in contact with all
parts of the furnace, thereby heating them uniformly. This arrangement will also
enable the furnace man to have easier access to the furnace bars to remove the
clinkers.

page_text: so that the burnt or injured portion may be replaced when desired; and, secondly, in
making the said furnaces in duplicate; and, thirdly, in raising and lowering the
grate bars and crucibles, and the application of a plate to the bottom of each
furnace to close it when required. And in order that any Invention may be fully
understood I will describe the accompanying sheet of Drawings, reference being
had to the figures and letters marked thereon.
Fig. 1 is an elevation in section, and Fig. 2 is a plan also in section of a pair of
furnaces made according to my Invention. a is the outer casing, and b is the lining
of the upper portion of the furnaces; and a¹ is the outer casing, and b' the lining
of the lower portion of the furnaces; c, c, are the covers; d' is the flue connecting
the furnaces; d, d, are the discharge flues; and dª, d³, the downward flues. The
outer casings are made of sheet iron or other metal, and the linings are made of
fire clay or other substance to resist the heat of the furnace, and the upper and
lower portions are connected together by bolts as shewn; e, e, are the grate bars,
and ff are shafts attached to the grate bars and screwed at their lower ends;
9, 9, are nuts which fit on the screwed portion of the shafts f, f, to raise and lower
the grate bars e, e, to move the crucibles up or down in the furnace; i, i, are
plates to close the bottom of either furnace when desired. Each of these plates is
provided with two annular flanges, and in the space between the annular flanges I
put sand so that when one of the plates is pressed against the bottom of the furnace
the sand prevents air from entering, so that the furnace in which no fuel is burning
may be heated by the flame from the adjoining furnace. These plates are attached
to the screwed shafts f. f, and are raised and lowered with the grate bars; k, k, ure
the crucibles to contain the steel or other metal placed upon fire clay stands that
rest upon the grate bars. In the Drawing the furnace marked A is shewn charged
with coke, and in the other furnace marked B the crucibles are shewn raised into
position to be heated by the flame from the furnace A. The downward Blue d' is
closed by a damper, and the downward flue d³ open, thus causing the flame to be
As soon as
drawn through the furnace B'in the direction shewn by the arrows.
the metal is melted in the furnace A the crucibles are withdrawn, and the crucibles
from B may be put into A with a fresh charge of coke to complete the melting of
the metal contained in them, and crucibles containing fresh metal may be put into
B; or the grate bars and crucibles may be lowered in B with the plate, i', and a
fresh charge of coke put into B, the flue d³ closed and the flue d² opened, and
crucibles containing fresh metal are put into the furnace A and raised into position
with the plate i, as shewn on the Drawing, in furnace B and the operation reversed.
Having thus stated the nature of my Invention and described the manner of
performing the same, I wish it to be understood that I do not limit myself to the
details given as the same may varied or modified, but what I claim is,―
First. Making the casings and linings of furnaces for melting metal in crucibles
in separate portions, substantially as shewn and described, so that the burnt or
injured portion only of the lining may be replaced when desired.
Secondly. Making furnaces for melting metal in crucibles in duplicate, in the
manner and for the purpose shewn and described.
Thirdly. Raising and lowering the crucibles and grate bars and the plates i, i,
substantially as shewn and described.
In witness whereof, I, the said James Dodge, have hereunto set my hand and
seal, this Twenty fourth day of May,. One thousand eight hundred and