AN IMPROVED PROCESS OF MANUFACTURING SHEET IRON
Year: 1872

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London, for
the Invention of "AN IMPROVED PROCESS OF MANUFACTURING SHEET
IRON." A communication from abroad by William Rogers, of
Apollo, and Thomas Jefferson Burchfield, of Allegheny, both in
Pennsylvania, United States of America.
ealed the 15th November 1872, and dated the 23rd May 1872.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition,
on the 23rd May 1872.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for an "AN IMPROVED PROCESS OF MANUFACTURING
SHEFT IRON," to be as follows:-
The nature of this Invention consists in the process used for forming
upon the surface of sheet iron an oxide, which upon being worked into
the body of the sheet gives an ozidized polished surface resembling that
of the so-called "Russian sheet iron."

page_text: In practising the said Invention an annealing furnace is used which
has an iron bottom plate about two inches thick, provided with a large
number of apertures distributed equally over the plate for the purpose
allowing the heat to pass up through it.
of
The base of the stack of the furnace rests on the furnace crown near
the front side and above its charging door. The stack should be pro-
vided with a damper. The said furnace should be provided with an oven
about forty feet in length. This oven should be heated through the
medium of flues connected with a suitable fire-chamber or chambers.
The ends of the oven should be provided with suitable doors or other
means for closing them, allowing however an opening at each end of the
oven sufficiently long and deep for the passage of a sheet of iron into
and out from the oven. The sheets of iron may be carried through the
oven by means of an endless apron or other equivalent device.
66
"
A good article of wrought iron is taken and by means of suitable rolls
made into sheets of a gauge twenty-two to twenty-four; a sheet of
this iron is then coated or otherwise completely covered with particles of
charcoal about the size of a grain of wheat, care being taken to have
these particles evenly spread over the entire sheet. Another sheet of iron
is then laid upon this first sheet and in like manner covered on its upper
surface with similar particles of charcoal, and thus continuously sheet is
placed upon sheet until a pack is formed consisting of about forty sheets.
The edges are then clamped in the usual manner for forming packs of
sheet iron, and the pack is placed in a heating furnace with the under
sheet of the said pack resting upon the bottom plate. Then around the
edges of the pack, wood which has been thoroughly soaked and saturated
with water, is placed, forming a protecting wall. Then the mouth of
the furnace is closed to prevent the admission of air, and a fire is made
in the fire-chamber, wood being used as the fuel. After the fuel has
become completely ignited the damper is lowered, to retain in the
furnace the heat, smoke, and gases of the fire. After the iron has been
subjected to the action of the heat, smoke, and gases of the furnace until
each sheet in the pack has become red (which will require about two
hours) the pack is removed from the furnace and subjected to the action
of a steam hammer or other concussive or impinging force, for the
purpose of working into the body of each sheet the oxide which has been
formed thereon. The sheets are then repacked, care being taken to
bring those of the centre to the outside and those of the outside to the

page_text: inside of the pack, thus interchanging consecutively the centre sheets.
The pack is again subjected to heat in the heating furnace in the same
manner as in the first instance, and after being sufficiently heated
is removed and again subjected to the hammering or equivalent force.
This packing, heating, and hammering process is repeated four or five
times, which will as a general rule sufficiently work into the iron the
oxide formed on the surfaces of the sheets, and thereby give it the
necessary finish and polish. The sheets are then trimmed by the
shearing process, and are severally passed through the annealing oven,
which will anneal and properly color them in a single passage through
The sheets are now finished and are in a merchantable
the oven.
condition.
Iron scales and other metallic oxides may be combined with the char-
coal in covering the surfaces of the sheets in forming the pack for the
furnace, and such combination answers as a good substitute for the
charcoal alone. But it will be found that charcoal, uncombined with
other matter, will be sufficient to produce the desired result when it is
used in the manner herein-before described. The edges of the pack may
be protected by the use of clay or other earthy and mineral matters
moistened with water to make it adhesive, but wood soaked and
thoroughly saturated in water is the best protection for the edges of
the pack.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 20th November 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of May, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Robert Lake, Her special
licence that I, the said William Robert Lake, my executors, administra-

page_text: tors, and assigns, or such others as I, the said William Robert Lake, my
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "AN IMPROVED
PROCESS OF MANUFACTURING SHEET IRON," a communication to me from
abroad by William Rogers, of Apollo, and Thomas Jefferson Burchfield,
of Allegheny, both in Pennsylvania, United States of America, upon
the condition (amongst others) that I, the said William Robert Lake,
my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawing forming a part of this Specification :-
The nature of this Invention consists in the process used for forming
upon the surface of sheet iron an oxide, which upon being worked into
the body of the sheet gives an oxidized polished surface resembling that
of the so-called "Russian" sheet iron.
DESCRIPTION OF THE DRAWING.
Figure 1 is a vertical section of a heating furnace; and, Figure 2
is a vertical transverse section of an annealing furnace used in the said
process.
A, in Figure 1, represents the fire chamber of the heating furnace ;
B, its ash pit; C, the bridge wall; D, D, are flues. e is an iron bottom
plate, about two inches thick, and provided with a large number of
apertures distributed equally over the plate for the purpose of allowing
the heat to pass up through it. The dotted lines represent the stack
of the furnace, the base of which rests on the furnace crown / near the
front side and above its charging door. The stack should be provided
with a damper as indicated at i.

page_text: The annealing furnace, represented in Figure 2, is provided with an
oven j, which should be about forty feet in length. This oven should be
heated through the medium of flues, as indicated at k, connected with
a suitable fire chamber, or a number of such chambers. The ends of the
oven should be provided with suitable doors or other means for closing
them, allowing however an opening at each end of the oven sufficiently
large in length and depth for the passage of a sheet of iron into and out
from the oven j. I propose carrying the sheets of iron through the oven
by means of an endless apron or other equivalent means.
Having thus described the furnaces to be used in this improved process
for manufacturing sheet iron, I will now proceed to describe another
part of the said Invention.
A good article of wrought iron is taken, and by means of suitable rolls
is rolled into sheets of a "
gauge," twenty-two to twenty-four. Then a
sheet is coated or otherwise completely covered on its surface with par-
ticles of charcoal of about the size of a grain of wheat, care being taken
to have these particles evenly spread over the entire sheet, then another
sheet of iron is laid upon this first sheet, and in like manner its upper
surface is covered with like particles of charcoal, and thus I continue to
place sheet upon sheet, covering the upper surface of each until a pack
is formed consisting of about forty sheets. Then the edges are clamped
in the usual manner for forming packs of sheet iron and the pack is
placed in the heating furnace, represented in Figure 1, with the under
sheet of the pack resting upon the bottom plate e. Around the edges
of the pack is placed wood which has been thoroughly saturated with
water, forming a protecting wall, as indicated at in Figure 1. The
mouth of the furnace is then closed to prevent the admission of air
into it, and a fire is lighted in the fire chamber A, using wood as
the fuel. After the fire has become completely ignited, the damper i
is lowered, so as to retain in the furnace the heat, smoke, and gasses
of the fire. After the iron has been subjected to the action of the
heat, smoke, and gases of the furnace until each sheet in the pack has
become red, (which will require about two hours) the pack is removed
from the furnace and subjected to the action of a steam hammer, or
other concussive or impinging force, for the purpose of working into the
body of each sheet the oxide which has been formed thereon. Then the
sheets are repacked, care being taken to bring those of the centre to
the outside, and those of the outside to the inside of the pack, thus

page_text: interchanging consecutively the centre sheets. The pack is again sub-
jected to heat in the heating furnace in the same manner as in the first
instance, and after being sufficiently heated is removed and again
subjected to the hammering or equivalent force. This packing, heating,
and hammering process repeated four or five times will, as a general
rule, sufficiently work into the iron the oxide formed on the surfaces
of the sheets, and thereby give it the necessary finish and polish. The
sheets are then trimmed by shearing, and are severally passed through
the annealing oven, which will be sufficient to anneal and properly
color them in a single passage through the oven. The sheets are now
finished and are in a merchantable condition.
By subjecting sheet iron to the process herein-before described its
body becomes tough and pliable, with a smooth and polished surface,
which is not liable to rust, crack, or scale off. It has been found by
experiment that iron scales and other metallic oxides may be combined
with the charcoal in covering the surfaces of the sheets in forming
the pack for the furnace, and that such combination answers as a
good substitute for the charcoal alone. But it will be found that
the use of the charcoal without combining it with other matter will be
sufficient to produce the desired result when it is used in the manner
herein-before described. It has also been found that the edges of the
pack may be protected by the use of clay or other earthy and mineral
matters, moistened with water to make them adhesive, and that they
answer in many respects for the wood protection herein-before described.
Experience, however, has demonstrated that wood thoroughly saturated.
in water is the best protection for the edges of the pack.
Having thus fully described the said Invention, as communicated to
me by my foreign correspondents, and the manner of performing the
same, I wish it understood I am aware that charcoal has been placed
between the sheets of a pack of sheet iron prior to subjecting it to a
hammering or rolling process, and that sheet iron after having its surfaces
cleaned by a chemical solution or otherwise, so as to remove the scales
or oxide from it, has been provided with a delicate surface of oxide by
the action of heat, and then subjected to a rolling or hammering process;
but I do not claim these latter processes as forming any part of this
Invention or process, but I claim,―
First. The herein described method and process of heating and mani-

page_text: pulating iron in sheets for the purpose of furnishing it with an oxidized,
colored, and polished surface, as herein set forth.
Second. Surrounding the outer edges of the pack herein described,
with wood previously saturated with water, in the manner and for the
purpose set forth.
Third. The use of clay or other earthy or mineral matter for the
purpose of protecting the outer edges of the "pack" while subjecting it
to the action of heat, as herein described.
Fourth. Repacking the "pack" by interchanging the position of the
sheets with relation to each other, in the manner herein described, and
for the purpose set forth.
Fifth. Annealing and coloring iron, heated as herein-before described
by passing it through a heated chamber, in the manner set forth.
In witness whereof, I, the said William Robert Lake, have here-
unto set my hand and seal, this Nineteenth day of November, in
the year of our Lord One thousand eight hundred and seventy-
two.
Witness,
W. J. LOWE.
W. ROBT. LAKE. (L.S.)