AN IMPROVED PROCESS OR METHOD OF FINISHING OR FORMING A SURFACE OR COATING UPON SHEET IRON
Year: 1878

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 OR METHOD OF FINISHING OR FORMING A SURFACE OR
COATING UPON SHEET IRON." A communication from abroad by Charles
James Eames, of the City and State of New York, United States of America.
Sealed the 14th May 1878, and dated the 27th March 1878.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 27th March 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "AN IMPROVED PROCESS OR METHOD OF
FINISHING OR FORMING A SURFACE OR COATING UPON SHEET IRON." A com-
munication from abroad by Charles James Eames, of the City and State of New
York, United States of America.
This Invention relates to a process in which iron sheets during rolling and
finishing have produced upon them a black or blue-black glossy film or coating that
is highly resistent to corrosive agencies, does not tarnish in the air, and is capable
of being planished by rolling or hammering the sheet without detachment there-
from.
The said Invention consists in the application successively to an iron sheet, while
the same is heated and before its final rolling, first of a carbonaceous material, either
solid, liquid, vaporous, or gaseous; and, second, of steam heated to the temperature
of incandescence of solid matter.
The form in which I prefer to apply the carbonaceous matter in the first stage is
in that of vapor of petroleum or naptha, either with or without a small admixture
of steam.
In carrying this Invention into practice the sheets are first divested of oxide or
other foreign matter by the usual scouring or pickling, or otherwise.

page_text: The first stage of my peculiar process is that of carbonization, and the method of
carbonizing preferred is to arrange the iron sheets or plates within a closed casing
or box vertically, with spaces between them, this casing being heated to a dark red
heat, just visible in daylight. A jet of highly heated vapor of petroleum or naptha
is then introduced, preferably from a suitable generator or vaporizing apparatus,
from which the vapor of the whole mass of oil is carried forward bodily by means
of a current of incandescent steam. The sheets are subjected to this carbonizing
operation in an atmosphere of highly heated hydrocarbon vapor for a period of about
ten or fifteen minutes.
The casing may be heated to a higher degree externally, and vapor of hydrocarbon
may be introduced in any convenient way, but this operation is liable to consume
much time. Equivalent results also follow from the application to the sheets of
solid or liquid carbonaceous matters, and external heating of the casing, but this
modification of my process is expensive and tedious.
The second stage of my improved process consists in a treatment of the sheet iron
with highly heated steam alone. This is accomplished by turning off the current of
hydrocarbon vapor from the box or casing containing the sheets, and admitting the
incandescent steam alone into the casing; this stage of the said process usually
continues for a period of about twenty to thirty minutes. A longer period may
produce a brittle coating of magnetic oxide, which is not susceptible of being
planished.
The third stage of my process is the production of a planished surface by heating
and rolling. For this purpose the sheet iron is placed in piles of three sheets, which
from time to time are interchanged in relative position to ensure uniform planishing
on all of the surfaces.
If desired the mottled surface peculiar to Russia sheet iron is then imparted by
heating and hammering with hammers having tesselated faces in the manner now
commonly practised.
One great advantage of my method of making planished sheet iron is the very
short time required in comparison to that required by the methods now in use.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I am aware of the application of carbonaceous matters to iron sheets in the
ordinary methods of manufacture, and also of its being well known that superheated
steam will effect superficial oxidation of iron, converting it to a magnetic oxide,
which however will not stand the planishing process, and I therefore do not claim
as iny Invention such ordinary or well-known methods or apparatus; but I claim,
the process of producing a coating capable of being planished upon iron sheets
by successively treating the same with hydrocarbon vapors or gases, or other
carbonaceous matters, and then with highly superheated steam, as above described.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty-seventh day of March, in the year of our Lord One
thousand eight hundred and seventy-eight.