Improvements in and connected with Annealing or Tempering Furnaces.
Year: 1896

page_text: Date of Application, 4th Jan., 1896-Accepted, 8th Feb., 1896
COMPLETE SPECIFICATION.
Improvements in and connected with Annealing or Tempering
Furnaces.
I, FERDINAND THEODOR FRANKE, of Dessau in the Duchy of Anhalt in the
German Empire, Manufacturer, do hereby declare the nature of this invention and
in what manner the same is to he performed, to be particularly described and
ascertained in and by the following statement :-
This invention relates to furnaces and vessels or pots for tempering or annealing
metals and is hereinafter described more particularly with reference to the manu-
facture of malleable castings but may be applied to furnaces and pots for other
analogous purposes.
The annealing furnaces hitherto used in the manufacture of malleable castings
and for other purposes have the defect that they heat the vessels or pots in them
and the castings contained therein only from the outside. As with annealing pots
of considerable size a relatively excessive beat has to be applied in order to heat
to a red heat all the castings packed into them, the fault arises that the castings
lying next to the outer walls of the pot are superheated and exposed to the action
of the tempering substances which surround them and are likewise superheated in
such a manner that they do not at all acquire the properties of really malleable
soft castings, and are frequently taken out of the vessels completely burnt and
useless for any purposes. The castings lying in the middle of the vessel on the
other hand are not sufficiently heated by the external heat to enable them to
incorporate the substances which impart to them the qualities of malleable
castings.
The heat produced in such tempering furnaces touches the annealing pots as
soon as generated and passes at once either directly from the furnace into the
chimney or into a flue connecting the furnace and chimney, so that a large part
escapes without being utilised. This necessitates a large consumption of fuel,
which would be reduced if the heat produced in the furnace were fully utilised.
The excessive heat required with such furnaces also causes a great wear of the
annealing pots.
The object of my invention is to obviate these defects and losses by means of an
improved arrangement of the tempering furnaces and pots.
On the drawing appended hereunto an improved tempering furnace and vessel
constructed according to my invention are represented,
Fig. 1 showing a sectional plan,
Fig. 2 a vertical section along line a-x, Fig. 1;
Fig. 3 a vertical section along line y-y, Fig. 1;
Fig. 4 a front view.
Referring to the drawings: the brick setting a is built with a cylindrical
A flue d passes
chamber, in the middle of which the conical seating c is raised.
through the seating caud leads to the chimney. Round the seating c the grate
bars are arranged. The fuel is fed upon the grate through the charging hole g,
while the space h underneath the grate bars f forms the ashpit.
Upon the conical seating c the annealing vessel or pot i is placed, containing a
circular opening k in its bottom, above the flue d. In the centre of the pot i is
placed a pipe provided with flanges m at each end. The lower flange fills in the
opening k or may be connected to the bottom of the pot i, while the upper one

page_text: serves as support for the annular cover n. Another cover o closes the top of the
chamber in the brick setting.
The heat produced in this furnace first heats the chamber b and the outer walls
of the annealing pot or vessel i, then passes over the cover n and heats it, and
proceeds down through the pipe 7, heating the central part of the annealing pot
before escaping into the flue d and chimney e.
By this way of conducting the heat the annealing pot or vessel is heated uniformly
and at the same time all over. A superheating of its outer wall, as required with
the previous vessels in order to heat the castings in the centre sufficiently, is
excluded and all the castings in the pot are always heated and cooled uniformly.
For this reason the tempered castings are all equal in quality, a result which
cannot be obtained with other kinds of pots, and furnaces.
The pipe and flue passing through the pot and furnace not only effect a saving
of fuel, but also of annealing pots or vessels, because an excessive or over-heiting
of the outside wall is no longer necessary in order to conduct sufficient heat to the
centre of the pot.
Obviously more than one flue pipe passing through the pot and corresponding
flues in the conical seating may be arranged and the vessels and pipes may be
cylindrical or of any other suitable form.
Besides for annealing malleable castings, the furnace and pot may be used for
other tempering or annealing operations.
Having now particularly described and ascertained the nature of my inveu-
tion and in what manner the same is to be performed, I declare that what I
claim is,
1. In annealing or tempering furnaces and pots or vessels, the arrangement of
one or more flue pipes and flues passing through the pots or vessels and their
seatings, substantially as herein before described and for the purposes set forth.
2. The arrangement or construction of annealing or tempering furnaces and
pots or vessels substantially as hereinbefore described and illustrated by the
drawings.
Dated this 2nd day of January 1896
R. J. URQUHART,
57, Barton Arcade, Manchester, and 5, Clayton Square, Liverpool,
Consulting Engineer and Patent Agent.