IMPROVEMENTS IN ANNEALING POTS."
Year: 1876

page_text: LETTERS PATENT to Lewis Griffiths, of Swansea, in the County of Glamorgan,
Engine Fitter, for the Invention of "IMPROVEMENTS IN ANNEALING POTS."
PROVISIONAL SPECIFICATION left by the said Lewis Griffiths at the Office
of the Commissioners of Patents on the 17th February 1870.
LEWIS GRIFFITHS, of Swansea, in the County of Glamorgan, Engine Fitter.
"IMPROVEMENTS IN ANNEALING POTS."
This Invention relates to improvements in annealing pots used in the manu-
facture of tin plates for annealing the plates previous to their being cased with
tin.
The defects in the annealing pots now in general use cause a great deal of trouble
and expense, the pots rapidly deteriorating in the heating furnace. And again,
when the pots are brought from the heating furnaces on the carriages or bogies
after the plates are annealed, they are apt to be shaken, which causes the dust used
to make them air-tight to disperse and permit of the admission of air into the pots,
which is very detrimental to the plates being annealed.
The object of my Invention is to obviate these defects, and the Invention consists
in forming the annealing pot in three parts, which may be respectively termed the
stand, the frame, and the top or cover. This permits of each part being renewed
independently of the other. The stand is cast with an inner and outer flange so as
to form a groove or trough around the bottom or stand of pot to receive the frame
of the pot, which trough when the sides are in position is filled with dust in the
usual manner for the purpose of forming an air-tight joint. A similar arrangement
of groove or trough is cast at the top of the frame to receive a flange, which projects
downwards and forms part of the top or cover. This groove or trough is also filled
with dust for the purpose above explained. Any vibration to which the pots may
be subjected by the action of moving them from the heating furnaces on to the
bogies will have a tendency, to compress the dust in these troughs, which will make
the pot perfectly air-tight.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Lewis Griffiths in the Great Seal Patent Office on the 17th August
1876.
LEWIS GRIFFITHS, of Swansea, in the County of Glamorgan, Engine Fitter.
"IMPROVEMENTS IN ANNEALING POTS."
This Invention relates to improvements in annealing pots used in annealing
iron plates or sheets previous to their being coated with tin or terne, or any
other material in the manufacture of tin or terne plates.
In annealing pots as at present constructed, whether of wrought or cast iron, it
often occurs that through bad welding in the wrought-iron pots, and the cracking
of the cast iron through exposure to heat, or cold air is admitted into the pots,
thereby damaging the iron sheets or plates contained therein, and rendering the
pots if of cast iron wholly useless, and, if of wrought iron useless until rewelded.
My improvement consists in making the pot of three separate main parts, viz.,
the stand, the frame or shell, and the cover, and in providing means for effectually
closing the joints of the pot. Thus if one part of the pot be destroyed, damaged, or
put out of order, it may be replaced by another corresponding part without its being
necessary to renew the whole. The stand which is usually cast with flanges or
rings to form a trough for the reception of sand or loam for scaling the joint of the
pot I cast without a flange, and the flange, flanges, or rings I make separate from
the stand or in such a way that they may be rivetted or screwed to the stand.
The frame or shell which rests in the trough is formed with a lid or cover, and by
preference I place within the frame or shell a tube or cylinder closed at top for
covering the plates to be annealed, and protecting them from the action of the air
in case the pot should through a crack or flaw permit of the passage of air to the
interior thereof.
By forming the flanges or rings separate from the stand it will be evident that if
they become accidentally or otherwise broken, or if when made of wrought iron
become bent or distorted in shape by exposure to either heat or cold, or otherwise,
they can be readily straightened to their original shape; or in the case of a rivetted
or screwed flange which may have become bent or distorted, the rivets may be
knocked out and the screws unscrewed, and the flange or ring or angle iron may be
straightened into its original shape and rerivetted or rescrewed. The stands can thus
be made to last until they become too thin and weak to hold the weight of plates
they are intended to hold. As a further security against cracking by expansion I
rivet the feet to the wrought or cast-iron stand, instead of welding or casting them
to or with the body of the stand. The feet may be made of either wrought or cast
iron, and rivetted to the stand by a rivet or screw passing through. the foot, and
countersunk or screwed into the body of the stand. The shell has a movable or
loose top which on being removed admits of the possibility of placing between the
shell and the tube, or in the trough, sand or any other material for sealing or luting
the plates to be annealed.
The upper and lower parts of the shell are troughed or bevilled for the purpose
of making a receptacle for the sand or sealing or luting materials, and to support the
cover by acting as an abutment or seating for it at the top, as well as to allow of
the shell being turned upside down after the top has become worn by the action of
heat and incrustation, while the bottom remains undamaged. The trough or bevil
may be replaced at the top or bottom of the shell by rivetting a piece of iron or
any other suitable material to its sides.
In the accompanying Drawing I have shown the manner of carrying out my
Invention.
Fig. 1 is a longitudinal vertical section of one of my improved annealing pots ;
A is the stand made of cast or wrought iron, and upon it the plates to be annealed
are placed. Over these plates is set a cylinder B made of wrought iron or any other
suitable material. The object of the cylinder B is to protect the plates from

page_text: atmospheric action in case a crack should occur in the cast-iron shell C, or a flaw in
case the shell be made of wrought iron. The shell C has a removable or loose top
D which admits of the placing between the shell C and the cylinder B sand or other
material for sealing or luting the pot. The lower edge of the shell C rests in a
groove or trough formed on the stand A by the screwed or rivetted flanges or rings
E, E; and when the stand A is in place, the groove or trough is filled with sand or
dust in order to form an air-tight joint. If preferred, the flange E, which appears as
inside the shell C may be cast with the stand, and the outer flange may be a loose
ring. A groove or trough is formed at the upper end of the shell C to receive the
edge of the cover D, and when this groove is filled with sand or dust it will form
an air-tight joint. The lid or cover D is provided at top with a ring or handle,
whereby it may be lifted off the shell C wlien required.
Fig. 2 is a longitudinal vertical section of an annealing pot which is a modi-
fication of that shown at Fig. 1. It will be seen that in Fig. 2 the upper and
lower parts of the shell C are bevilled outwards, and thus, form with the flange or
ring E of the stand a receptacle for the sand or sealing or luting materials at the
bottom, and the top serves to support the cover or lid D by acting as an abutment
or seating for the latter to rest upon. As the bevilled edges of the shell C are the
same at both ends, it will be seen that the shell may be turned upside down
when the top has become worn by the action of heat and incrustation, while the
bottom remains undamaged (so to speak). Instead of the bevil at the top or
bottom a piece of iron may be rivetted to the sides of the shell C so as to forin
a support for the lid or cover D.
From the foregoing description it will be understood that the objects I have
had in view were, first, to so construct and arrange the various parts that the
plates may be properly annealed without the risk of their being damaged by the
access of air through accidental cracks, crevices, or flaws in the apparatus; and
secondly, quickly and economically to repair any damages of the pots that may
arise, and that both these objects are attained by the arrangements shewn at
Figures 1 and 2.
Having now set forth the nature of my Invention of "Improvements in
Annealing Pots," and explained the manner of carrying the same into effect, I wish
it to be understood that under the above in part recited Letters Patent I claim
constructing annealing pots, and providing against the access of air to the interior
thereof, as and for the purpose above described.
In witness whereof, I, the said Lewis Griffiths, have hereunto set my hand
and seal, the Sixteenth day of August, in the year of our Lord One
thousand eight hundred and seventy-six.
L. GRIFFITHS. (L.S.)