IMPROVEMENTS IN PREPARING SHEET IRON IN OR FOR THE MANUFACTURE OF TIN AND TERNE PLATES, OR FOR GALVANIZING, AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1878

page_text: LETTERS PATENT to John David Grey, of Aberavon, in the County of
Glamorgan, for the Invention of "IMPROVEMENTS IN PREPARING SHEET IRON IN
OR FOR THE MANUFACTURE OF TIN AND TERNE PLATES, OR FOR GALVANIZING,
AND IN THE APPARATUS EMPLOYED THEREIN."
Sealed the 3rd December 1878, and dated the 6th June 1878.
PROVISIONAL SPECIFICATION left by the said John David Grey at the
Office of the Commissioners of Patents on the 6th June 1878.
JOHN DAVID GREY, of Aberavon, in the County of Glamorgan.
IN PREPARING SHEET IRON IN OR FOR THE MANUFACTURE OF TIN AND TERNE
PLATES, OR FOR GALVANIZING, AND IN THE APPARATUS EMPLOYED THEREIN."
"IMPROVEMENTS
The objects of this Invention, which relates to improvements in the method of
and apparatus for preparing sheet iron in or for the manufacture of tin and terne
plates, or for galvanizing, are to dispense with the usual troublesome and costly
processes of "pickling" and "black annealing," forming part of the treatment to
which sheet iron, as hitherto prepared in the manufacture of tin and terne plates or
for galvanizing, has been subjected, and generally to simplify the treatment of the
sheet iron, with a view to turning out an increased quantity in a less time than as
at present, and to attain an improved result.
In the usual treatment of the sheet iron, after it has been rolled and trimmed to
the desired thickness and size in packs of about eight sheets, and opened apart into
single sheets, the sheets are "pickled" in a bath of sulphuric acid diluted with
water, for the purpose of removing the oxide or scales from the surface of the sheet
iron, and after they have remained sufficiently long in such bath to have such oxide
or scales removed, they are removed therefrom and placed into a tank of water for
the purpose of washing away or removing the adhering acid. After this pickling
process the sheets are placed on a cast-iron stand, and are covered with a cast-iron
1

page_text: box and placed therein, into an annealing furnace, and generally left to remain therein.
from ten to twelve hours for the purpose of annealing the sheets preparative to the
cold rolling process. This process is called by the trade "black annealing," and is
a very expensive operation, on account of the stands and boxes being soon burnt
out by the heat to which they are subjected in the annealing furnace.
Now, according to my Invention, instead of pickling the sheets as above described,
I dip them into a bath of muriatic acid diluted with water, after which I place them
on their edges to drain, and then place them singly on an endless chain or rack
travelling through a furnace (the chain or rack being supported on pulleys and
driven by steam or other suitable motive power), for the purpose of raising the oxide
or scales by heat, and not by a bath of sulphuric acid, as at present practised. On
emerging from this furnace the sheets pass between a pair of rolls (placed conve-
niently near the endless chain or rack), for the purpose of straightening them and
breaking any surface scale thereon, and after passing through the rolls they drop,
while still hot, into a tank of water (placed conveniently near the rolls), for the
purpose of loosening and washing the scales away from the surface of the sheets.
After the sheets are washed and taken out of the water they are placed on another
endless chain or rack travelling through a drying oven (placed conveniently near
the water tank, the chain or rack being carried and actuated as above referred to),
for the purpose of drying the sheets preparative to the usual cold rolling process.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John David Grey in the Great Seal Patent Office on the 6th
December 1878.
JOHN DAVID GREY, of Aberavon, in the County of Glamorgan. "IMPROVEMENTS
IN PREPARING SHEET IRON IN OR FOR THE MANUFACTURE OF TIN AND TERNE
PLATES, OR FOR GALVANIZING, AND IN THE APPARATUS EMPLOYED THEREIN."
The objects of this Invention, which relates to improvements in the method of
and apparatus for preparing sheet iron in or for the manufacture of tin and terne
plates, or for galvanizing, are to dispence with the usual troublesome and costly
processes of "pickling" and "black annealing," forming part of the treatment to
which sheet iron, as hitherto prepared in the manufacture of tin and terne plates or
for galvanizing, has been subjected, and generally to simplify the treatment of the
sheet iron, with a view to turning out an increased quantity in a less time than at
present, and to attain an improved result.
In the usual treatment of the sheet iron, after it has been rolled and trimmed to
the desired thickness and size in packs of about eight sheets, and opened apart into
single sheets, the sheets are "pickled" in a bath of sulphuric acid diluted with
water; for the purpose of removing the oxide or scales from the surface of the sheet

page_text: iron, and after they have remained sufficiently long in such bath to have such oxide
or scales removed, they are removed therefrom and placed into a tank of water, for
the purpose of washing away or removing the adhering acid. After the pickling
process the sheets are placed on to a cast-iron stand, and covered with a cast or
wrought iron box, and placed therein into an annealing furnace, and generally left
to remain therein from ten to twelve hours, for the purpose of annealing the plates
preparative to the cold rolling process. This process is called by the trade "black
annealing," and is a very expensive operation on account of the stands and boxes
being soon burnt out by the heat to which they are subjected in the annealing
furnace.
Now, according to my Invention, instead of pickling the sheets as above described,
I dip them into a bath of muriatic acid diluted with water, after which I place them
on their edges to drain, and then place them singly on to endless chains 1 (or on to a
rack or racks, or other equivalent carrying device), travelling through a furnace 2,
as illustrated in Figure 1 of the accompanying Sheet of Drawings, for the purpose
of raising the oxide or scales by heat, and not by a bath of sulphuric acid, as pre-
viously practised, the chains 1 or other carrying device being supported by pul-
leys 3, 4, the latter of which are driven by steam or other suitable motive power..
On emerging from the furnace the sheets 5 pass between a pair of rolls 6 (placed
conveniently near the chains 1) for the purpose of straightening them and breaking
any surface scale thereon; and after pasing through the rolls 6, they drop while
still hot into a tank 7, containing water (placed conveniently near the rolls 6), for
the purpose of loosening and washing the scales away from the surface of the
sheets 5. After the sheets are washed and taken out of the water, they are placed
on to other endless chains 8 (or other equivalent carrying devices), travelling through
a drying oven -9, as illustrated in Figure 2 (placed conveniently near the water
tank 7, the chains 8 or other carrying device being supported and actuated, as above
described, with reference to Figure 1), for the purpose of drying the sheets prepara-
tive to the usual cold rolling process, and on emerging from the drying oven the
plates descend an inclined plate or shoot 10, whence they are removed to where they
are required to complete their manufacture in the way usually effected.
Figure 3 represents an end view of the furnace, 11 representing the fire-place,
12 the flue, and 13 the chimney or stack. The furnace and the drying oven are of
similar construction, and present a similar appearance in end view. The use of both
however is necessary to dispense with the two processes of "pickling" and "black
annealing," as a much higher degree of heat is required in the furnace to raise the
scale than in the oven to dry the plates; but should it be desired to pickle the plates
in sulphuric acid, as at present practised, and to dispense with the usual black
annealing only, then the drying oven only need be used. The chains 1, 8, are
kept taut or straight by tightening pulleys 14; 15 represents the bottom of the
furnace.
Having now described the nature and objects of my said Invention, together
with the manner in which the same is to be or may be performed or carried into
practical effect, I would remark in conclusion that I claim as my Invention,-
The above-described improvements in the method of and apparatus for preparing
sheet iron in or for the manufacture of tin and terne plates or for galvanizing,
substantially as and for the purposes described, and as illustrated on the accom-
panying Sheet of Drawings.
And especially I claim, the dispensing with the usual costly and troublesome
processes of "pickling" and "black annealing" the plates in the manufacture or
preparation thereof, as hitherto practised, and the effecting the desired result by the
much less troublesome, inexpensive, and more expedient means above described, and
consisting in dipping the sheets into a bath of muriatic acid diluted with water,
subsequently draining them, then passing them through a furnace, washing them,
and drying them by passing them through a drying oven, substantially as above
described.

page_text: And the application and use of travelling chains, or of racks or other equivalent
carrying devices for carrying the plates through the furnace and drying oven, and
of a pair of rolls placed close by the furnace, and of a tank of water into which
the sheets drop from the rolls while hot, all substantially as and for the purposes
respectively herein-above specified, and as illustrated on the accompanying Sheet of
Drawings.
In witness whereof, I, the said John David Grey, have hereunto set my hand
and seal, this Third day of December, in the year of our Lord One thousand
eight hundred and seventy-eight.