IMPROVEMENTS IN CONSTRUCTING FURNACES OR TANKS FOR MELTING GLASS, AND FOR OTHER SIMILAR PURPOSES, AND AN IMPROVED MIXTURE OF MATE- RIALS TO BE USED THEREIN
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Francis Thompson Woodcock at the
Office of the Commissioners of Patents on the 12th July 1877.
FRANCIS THOMPSON WOODCOCK, of Woodford, Berkeley, in the County of Gloucester,
Engineer. "IMPROVEMENTS IN CONSTRUCTING FURNACES OR TANKS FOR MELTING
GLASS, AND FOR OTHER SIMILAR PURPOSES, AND AN IMPROVED MIXTURE OF MATE-
RIALS TO BE USED THEREIN."
This Invention relates to improvements in the construction of furnaces or tanks
used for melting glass, and for other similar purposes, and to an improved mixture
or compound of materials to be used in the making of such furnaces or tanks. Such
furnaces or tanks are at present generally constructed of large bricks or
"burrs,"
which are usually first burnt in a kiln, portions of which usually break off at the
joints, and through being joined at the bottom whole bricks or "burrs" frequently
rise up, and so not only destroy the furnace or tank, but the metal contained in it,
causing great loss and much inconvenience to the manufacturer.
According to this Invention I thoroughly incorporate a mixture of dry fire-clay
and sand, and grind the same, with the addition of sufficient water, into a suitable
plastic condition for working.
In the case of a new furnace or tank I take an iron or other suitable casing,
and either in the place where the tank or furnace is to remain or in a separate
arch or place where the said casing is placed on rollers, on a tramway laid so that
the whole tank may be placed by the aid of screw jacks or other suitable means
under the arch of the furnace, when the casing is in position, and properly
fastened together, allowance being made in the fastenings for the expansion of the
materials when heated. I take the mixture and ram it tightly against the sides and
bottom of the case to the thickness of about three or four inches, taking care to
make all internal angles concave. When this coating is settled and firm I add or
lay additional layers in a similar manner until the required thickness, which is
usually about from 14 to 18 inches, is attained. In the case of a new tank built
in a separate arch I next gradually apply fire-heat to dry the materials, and in
case of a tank built under the arch of the furnace I apply the heat in the usual
manner adopted in such furnace; and in either case, when the tank or furnace gets
red hot, and cracks appear in the surface of the lining, I apply some of the mixture
dry to fill up all crevices, and when all are filled up I fire the same again strongly,
ID OJ 1

page_text: and if more cracks appear I fill them again with the mixture in a dry state mixed
with 5 per cent. of borax.
In case of an old tank or furnace, I take a mixture of clay and sand as before,
and after breaking off all the glass attached to the sides and bottom, I proceed to fill
in all the cavities with the mixture, and then proceed as for a new tank or furnace,
only in this case, as the tank will be hot, the material must not be so moist, and
must be rammed harder and put on quickly.
The mixture I prefer using is composed of two parts of dry fire-clay and one
part of sand, but as these materials vary so much in quality, I do not confine myself
to these proportions, but I propose to mix the materials according to the require-
ments of the materials, making a mixture that will burn well without excessive
cracking when the heat is applied. For the final dressing I add 5 per cent. of borax
to the mixture of clay and sand.