IMPROVEMENTS IN THE PROTECTION OF IRON SURFACES, AND IN CLEANING THE SAME
Year: 1876

page_text: LETTERS PATENT to Frederick Settle Barff, of Kilburn, in the County of
Middlesex, Professor of Chemistry, for the Invention of "IMPROVEMENTS IN
THE PROTECTION OF IRON SURFACES, AND IN CLEANING THE SAME."
Sealed the 12th May 1876, and dated the 29th February 1876.
PROVISIONAL SPECIFICATION left by the said Frederick Settle Barff at the
Office of the Commissioners of Patents on the 29th February 1876.
FREDERICK SETTLE BARFF, of Kilburn, in the County of Middlesex, Professor of
Chemistry. "IMPROVEMENTS IN THE PROTECTION OF IRON SURFACES, AND IN
CLEANING THE SAME.”
This Invention relates to the protection of iron surfaces, and to cleaning the
same, and consists in the production upon such surfaces, and from and in the iron
forming them of a film or scale of what is known as black oxide or magnetic oxide
of iron, the chemical symbol for whose molecule is FE, O oxide of iron, or which
'may in some cases be what is known as magnetic oxide of iron.
In carrying out this Invention I place plates, articles, or malleable or other iron,
or steel iron in other forms in a closed or partially closed vessel, retort, or chamber,
to which heat may be applied, and when the contents thereof have attained a
temperature sufficiently high to decompose steam, approaching that of redness, I
cause steam to be injected into the retort or chamber, so that by the united action
of heat and steam the desired film or coating of oxide shall be produced upon the
surface or surfaces of the iron it is desired to protect. I also, when convenient,
raise the temperature of the iron to be treated by the action of superheated steam,
and in this case the chamber is made of such a form as to best accomplish
my end.
When it is desirable in the first instance to clean the surfaces to be treated from
rust I propose to place the articles to be cleaned in a hot chamber, into which I
pass the hydrogen obtained from the water decomposed in the above described
treatment of the articles whilst being coated with black oxide.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frederick Settle Barff' in the Great Seal Patent Office on the 11th
August 1876.
FREDERICK SETTLE BARFF, of Kilburn, in the County of Middlesex, Professor of
Chemistry. "IMPROVEMENTS IN THE PROTECTION OF IRON SURFACES, AND IN
CLEANING THE SAME."
This Invention relates, firstly, in effecting or in the production of a protective
coating or film of oxide or of oxides of iron upon the surfaces of objects composed
either of iron or steel, by submitting such objects when at an elevated temperature
to the action of steam or by submitting the same to the action of superheated
steam.
Second. In effecting the removal or deoxidation of the oxide or oxides of iron or
rust existing upon the surface of the iron or steel objects to be treated by sub-
mitting the same at an elevated temperature to the action of hydrogen.
In carrying out the first part of my Invention I place the objects composed of
iron or steel in a muffle or chamber so constructed as that it may be in part or
wholly closed, and so that the contents of the interior of such muffle or chamber
may be raised by means of external heat to an elevated temperature, and when
the objects, or articles have acquired a temperature sufficiently elevated to cause
the decomposition of steam or of aqueous vapour when brought into contact there-
with I inject the same, and I continue the action of the steam or of the aqueous-
vapour until the desired protective film or coating of oxide has been produced, or
instead of submitting the objects or articles composed either of iron or of steel to
the action of heat in the manner herein-before mentioned I place the same in a
chamber capable of being wholly or partially closed, and I cause superheated steam
to be admitted and to circulate therein, and I continue this operation until the
desired protective film or coating of oxide has been produced.
In carrying out the second part of my Invention I cause the objects or articles
composed either of iron or steel from which it is desired to remove or reduce any
coating or film of oxide of iron or rust prior to their being submitted to the before-
mentioned oxidizing process to a deoxidizing process, and for this purpose I place
such objects or articles in a chamber or apparatus capable of being wholly or
partially closed, and so constructed as that the contents may be made to attain an
elevated temperature by the application of external heat, and when such articles or
objects have attained the desired temperature or such a temperature as will cause
the reduction of the oxide of iron to be effected by means of hydrogen, I admit
hydrogen gas obtained or resulting from the before-mentioned oxidizing process or
obtained from other sources, and I cause the same to come in contact with the
articles or objects until the desired reduction of the oxide has been effected.
After the objects or articles have been submitted to the first part of my Invention
I prefer to remove them when at an elevated temperature and to immerse them into
oil in the case of objects or articles composed of iron or steel, the protective
coating or film will thereby be rendered more tough and permanent, and in the
case of objects or articles composed of steel the temper which they will have lost
may be recovered, or any desired temper may be obtained, as is well understood in
the arts.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
One. Effecting the protection of iron or of steel surfaces from rust or corrosion
by submitting the plates, articles, or objects composed of the same to an elevated
temperature in conjunction with superheated steam or aqueous vapour, so that a

page_text: coating or film of oxide of iron, or what is commonly known as black oxide of
iron, may be formed thereon.
Two. The employment of hydrogen for the purpose of reducing the oxide or
oxides of iron or rust when existing upon the plates, articles, or objects prior to
their being treated in the manner herein-before described and for the purpose of
this Invention.
In witness whereof, I, the said Frederick Settle Barff, have to this my Speci-
fication set my hand and seal, the Second day of August, One thousand
eight hundred and seventy-six.
FREDERICK SETTLE BARFF. (L.S.)