IMPROVEMENTS IN THE MANUFACTURE OF SHEET IRON AND STEEL
Year: 1884

page_text: I, JOHN DAVID GREY, of Sarn House, near Bridgend, Glamorganshire, Iron
Manufacturer, Day, Davies & Hunt, Patent Agents, 321, High Holborn, in the
County of Middlesex, do hereby declare the nature of my Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF SHEET IRON AND STEEL
" to be as
follows:-
The object of this Invention, which relates to certain improvements in the
method of preparing sheet iron and steel for the manufacture of polished sheets, is
to create a thin scale of uniform thickness on the surface of the sheet, for the
purpose of protecting the iron from injury by rust, when exposed to a damp
atmosphere.
In the first place the iron or steel is rolled into sheets from the bar as ordinarily
practiced in rolling mills; and the sheets are taken without being previously
annealed and treated according to the present improvements, and the first process
towards converting the rolled sheets into polished sheets, is to remove the scale
formed upon the surface of the sheets during the process of rolling them from the
bars. The first scale formed upon, the sheet is of uneven thickness, and very
brittle, and will easily leave the sheet when it is bent backwards and forwards,
consequently exposing the white or pure iron underneath which is very
disadvantageous.
In accordance with the present improved process the first brittle scale formed
upon the surface of the sheets by rolling them from the bar, is removed for the
purpose of making the polished sheets, and the process is as follows:-
A tank or receptacle of wood or other suitable material, and of sufficient capacity
and dimensions, is used for containing the proper admixture of water and muriatic
acid. The sheets are dipped in the bath, and are then removed and placed upon
their edges to drain, after which they are placed in a reverberatory or other
suitable furnace, resting on iron bars, to prevent them from touching the bottom of
the furnace. The furnace should have a dead clear heat free from flame or smoke,
and as the sheets become red hot, the scale will commence to rise from both sides
of each sheet at once; they are then removed from the furnace, and plunged
while still hot into a tank of water, placed conveniently near the furnace, for the
purpose of loosening and washing the scales away from the surface of the sheet.
The operation of polishing the sheets thus prepared is accomplished in the
following manner; The sheets are made up in packs or parcels of four, or more,
and are then placed in a furnace convenient to the rolls, and heated to a dull red
heat, after which they are passed through the rolls, care being taken that the
sheets are kept loose while going through the process of being rolled. I would

page_text: here remark that if the sheets were allowed to stick together as is now practiced
in rolling sheet iron, the consequence would be, the stripping off or breaking of
the thin scale which is formed on the surface of the sheets while being reheated
for rolling. This thin scale or oxide covering the surface of the sheets, is of the
greatest importance in preventing the surface of the sheets from rusting when
exposed to a damp atmosphere, and it is the object of the present improved process
to create and preserve it intact.
During the process of rolling, the pressure is applied gradually by the screws in
the standards of the rolls, as ordinarily practiced in rolling sheets. After several
passes of the pack of sheets through the rolls, the polish caused by the pressure
and friction between the rolls will soon appear, and the sheets will rapidly assume
the desired degree of polish.
After passing through the rolling process, the sheets are then annealed by heating
them in an open furnace heated by charcoal, for the purpose of keeping the sheets
as free from sulphur as possible, care being taken not to heat the sheets beyond
a dark cherry red, as there is danger of injuring the polish, as well as starting the
scale, if too high a hent is used.
The sheets can also be annealed in a close Iron box, placed in a furnace and
heated to the required temperature, and cooled gradually.
After going through the annealing process, the sheets are then sheared to the
required size.
100A
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C.,
Agents for the Applicant.
COMPLÈTE SPECIFICATION.
Improvements in the Manufacture of Sheet Iron and Steel.
I, JOHN DAVID GREY, of Sarn House, near Bridgend, Glamorganshire, Iron
Manufacturer / Day Davies & Hunt, Patent Agents, 321, High Holborn, in the
County of Middlesex, do hereby declare the nature of my Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF SHEET IRON AND STEEL," and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:―
This Invention relates to certain improvements in the method of preparing sheet
iron and steel for the manufacture of polished sheets, the especial objects of the
Invention, and parts of the improved process of manufacture, being to remove the
first thick scale which is formed on the surface of the sheets during the process of
rolling them from the bar, to create a thin scale or oxide of uniform thickness on
the surface of the sheets for the purpose of protecting the iron from injury by rust

page_text: when exposed to a damp atmosphere, and to complete the manufacture of the
polished sheets by rolling them while loose in packs or parcels.
The first thick scale formed on the surface of the sheets during the process of
rolling them from the bar, as ordinarily practiced in rolling mills, is of an uneven
thickness, and very brittle, and will easily leave the sheet when the latter is bent
backwards and forwards, and as it then exposes the white or pure iron underneath,
it is very objectionable.
According to the improved process of manufacture herein described, the removal
of this scale is effected by taking the rolled sheets before or without annealing
them and treating them as follows;-
A tank or receptacle of wood or other suitable material, and of sufficient capacity
and dimensions, is used for containing an admixture of water and muriatic acid in
proportions which are not arbitrary, the strength of the solution depending princi-
pally upon the thickness of the scale to be removed. The rolled sheets are dipped
in this bath, and are then removed and placed upon their edges to drain, and are
afterwards placed in a reverberatory or other suitable furnace, resting on iron bars
to prevent them from touching the bottom of the furnace.
The furnace should have a dead clear heat, free from flame and smoke, and as the
sheets become red hot, the scale will commence to rise from both sides of each
sheet at the same time; they are then removed from the furnace, and plunged
while still hot into a tank of water placed conveniently near the furnace, for the
purpose of loosening and washing the scales away from the surface of the sheets.
The removal of the thick scale from the rolled sheets (as part of the complete
process of manufacture herein described) may also be effected but in a less satis-
factory degree by pickling the plates in acid diluted with water.
The creation of the thin preservative scale or oxide is then effected as follows;-
The sheets from which the thick scale has been removed as aforesaid, are made
up in packs or parcels of two or more, according to the required thickness of the
finished sheets, and are then placed in a furnace convenient to the rolls, and
re-heated to a cherry red heat, which causes the formation of a thin scale or oxide
of uniform thickness on both sides of each sheet, and which scale is so very thin
that it is not liable to break or fly off when the sheet is bent by seaming.
The manufacture of the polished sheets is then completed as follows;-
The packs of sheets from which the thick scale has been removed, and on which
the thin scale has been created as aforesaid, are then taken from the furnace, and
are placed on a stand or frame situated before the rolls, and each pack of sheets is
opened out so that each of the sheets is separated from those next adjacent to it
for the purpose of admitting air between the adjacent sheets to prevent them from
sticking to each other while being subsequently rolled and polished, so that the
thin preservative scale created may be preserved intact.
Each pack of sheets is then passed between the rolls, care being taken that the
sheets are kept loose while being rolled, and that the pressure of the rolls is
applied gradually, (by the screws in the standards of the rolls as ordinarily
practiced in rolling sheet metal,) and after several such passes of the pack of
sheets between the rolls, the polish caused by the continually increasing pressure
and friction between the rolls, soon appears, and the sheets rapidly assume the
desired degree of polish.
Either chilled or soft rolls can be used in rolling or polishing the sheets, the
former being preferred as they give a smoother polished surface to the sheets.
After being thus rolled and polished, the sheets are annealed by placing them on
an iron stand, covering them with an air-tight iron box, and placing the box and
contents in a furnace, care being taken not to heat the sheets beyond a dark cherry
red, as there would be a liability of injuring the polish, as well as of starting the
thin preservative scale if too high a heat is used in annealing.
When the sheets have thus been heated to the required temperature, the box
and contents are removed from the furnace and cooled gradually, after which the
sheets are sheared to the required size.

page_text: Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The hereinbefore described improved method of protecting sheet iron and
steel from injury by rust, by removing the thick brittle and uneven scale formed
upon its surface while being rolled from the bar, and by creating a new thin
tenacious polished scale thereon.
2. The berein before described improved process of carrying such improved
method into effect, and of manufacturing polished sheet iron and steel; the same
consisting in removing the said thick scale from the surface of the sheets, and in
then creating a new thin tenacious scale thereon, and in then rolling and polishing,
and finally annealing and shearing them; when such processes are effected
substantially as specified.
3. The hereinbefore described improved process of removing the said thick scale
from the surface of the rolled sheets, the same consisting in dipping them in an
admixture of water and muriatic acid, draining them, heating them to a red heat
in a suitable furnace free from flame and smoke, and in then plunging them while
bot into a tank of water, substantially as and for the purpose specified.
4. The herein before described improved process of creating a new thin preser-
vative scale or oxide of a uniform thickness on the surface of the sheets, the same
consisting principally in re-heating the sheets to a cherry red heat after having
removed the thick scale from them, substantially as and for the purpose specified.
5. The herein before described improved method of treating the sheets in
accordance with the present improvements in packs or parcels of two or more, and
in opening out such packs or parcels (after taking them from the furnace wherein
the thin scale is created on them,) so that each of the sheets is separated from
those next adjacent to it, so as to admit air between the adjacent sheets to prevent
them from sticking to each other while being subsequently rolled and polished.
6. The herein before described improved method of rolling and polishing the
sheets in packs or parcels in which the sheets are loose, the rolling being continued
under gradually increasing pressure until the desired degree of polish on the
surface of the sheets is attained.
Deted this 21st day of At 188x