AN IMPROVEMENT IN THE PROCESS OF REFINING AND PURIFYING CAST IRON FOR FOUNDRY AND FOR OTHER PURPOSES
Year: 1870

page_text: LETTERS PATENT to James Henderson, of New York, in the United
States of America, Engineer, for the Invention of "AN IMPROVEMENT
IN THE PROCESS OF REFINING AND PURIFYING CAST IRON FOR FOUNDRY AND
FOR OTHER PURPOSES."
Sealed the 22nd November 1870, and dated the 27th May 1870.
COMPLETE SPECIFICATION filed by the said James Henderson at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 27th May 1870, pursuant to the 9th Section of
the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
HENDERSON, of New York, in the United States of America, Engineer;
send greeting.
WHEREAS I am in possession of an Invention for “AN IMPROVEMENT
IN THE PROCESS OF REFINING AND PURIFYING CAST IRON FOR FOUNDRY AND FOR.
OTHER PURPOSES," and have petitioned Her Majesty to grant unto me,
my executors, administrators, and assigns, Her Royal Letters Patent

page_text: for the same, and have made solemn Declaration that I am the true
and first Inventor thereof.
NOW KNOW YE, that I, the said James Henderson, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed in and by the following
statement:-
:―
The object of this Invention is to remove from cast or pig iron silicon,
sulphur, and phosphorus, together with the required amount of carbon, in
order to improve its quality and condition for foundry and other
purposes, and it consists in treating such iron with fluor spar or other
fluoride in combination with oxides.
Various modes of carrying my improved process into practice may be
adopted, but one which I have tried with success, and which I consider
to be the best-is to reduce the fluor spar and other fluorides and also the
oxides to a finely divided state, and mix them thoroughly together and
then charge them evenly over the sole or hearth of any suitable rever-
beratory furnace. I prefer that the furnace should be provided with an
iron bottom arranged in a manner similar to the bottom of a boiling or
puddling furnace. Or the furnace may have a wrought-iron fettling or
bottom melted upon the cast-iron bottom of such furnace. After thus
placing the combined fluorides and oxides in the furnace or crucible I
charge ordinary cast or pig iron upon them, and when the iron is melted
it flows over the fluorides and oxides and dissolves or melts them, where-
upon their action upon the iron will be found to remove from it in the
form of vapour, or slag, or both, the silicon, sulphur, and phosphorus, and
a sufficient amount of the carbon, leaving the resulting metal refined and
very greatly improved for foundry purposes and many other uses.
In working my process it will be attended with the best results when
the average proportions of silicon, sulphur, and carbon present in the pig
or smelted iron which is produced at any particular works are first
ascertained, and when the per-centage of silicon contained in the oxides
to be used is also known. The requisite quantity of combined fluor spar
or fluorides and oxides can be easily estimated in any given case,
sufficient quantities being taken of the fluoride to remove the silicon
and silica as fluoride of silicon, and of the oxides to properly act upon or
oxidize the sulphur and phosphorus and the requisite amount of carbon
in the iron. Proper proportions of these agents will generally be about

page_text: 40 parts of fluor spar or other fluorides to every fourteen parts of
silicon and every 30 parts of silica by weight in the oxides, and the
proportions of the oxides should be sufficient to oxidize the sulphur and
phosphorus, and to oxidize and convert the requisite amount of carbon
into carbonic oxide or carbonic acid. But suitable quantities of the
fluorides and oxides for use in any particular case will be easily
determined by any practical chemist or metallurgist from the fore-
going instructions, and the above example is only given by way of
illustration.
For ordinary foundry purposes, or when good qualities of cast iron are
to be treated by this improvement, hematites or magnetic iron ores may
be employed for the oxides, and when it is desired to give special
strength and hardness to the cast iron I recommend that oxides be
employed which contain either manganese or titanic, chromic, or tungstic
acid. When it is specially wished to remove sulphur from the cast iron
I prefer to use manganesic oxides with fluor spar or other fluoride, or
such oxides in admixture with other oxides, and when both sulphur and
phosphorus are to be removed I generally employ oxides containing
titanic acid.
I wish it to be understood that I do not limit myself to practising my
improvement in the particular apparatus or manner which I have
herein described, as it may be performed in many different modes
which will suggest themselves to iron workers from the foregoing
directions.
And I may also remark that the combined fluorides and oxides may
be applied in the same manner as, and if preferred, at the same time with
or in connection with ordinary fluxes in any of the processes now used
for preparing crude iron to be converted into steel or wrought iron.
When, however, my process is practised in any apparatus other than a
cupola or reverberatory furnace it will usually be found desirable to heat
the fluorides or oxides by any convenient means until they become viscid
before the cast iron is run in upon them.
Cast or pig iron may by my improvement be freed from its silicon,
sulphur, and phosphorus, and from a part of its carbon and be rendered.
especially adapted for treatment by the "Bessemer," "Martin," or
puddling process, or it may be used for castings which will be of the
highest quality, and may be employed for a great variety of other
metallurgical purposes.

page_text: It is obvious that when the application of the present improvement is
carried so far as to leave in the metal treated no more carbon than about
one and seven-eighths per cent., or less, the product may be considered as
steel. This it is not the object of the herein-specified process to produce,
as such application of combined fluorides and oxides are covered by
other Letters Patent obtained by me.
And I may also state that from the foregoing description it will bo
obvious to any practical metallurgist that this process, if desired, may be
so performed as to remove only the silicon, sulphur, and phosphorus from
the cast iron without substantially affecting the carbon, but I usually 1
prefer that more or less of the carbon shall be removed also.
Having thus made known my Invention and shown how the same
may be conveniently and advantageously carried into practice, I wish it
understood that I claim, the herein-described process of refining and
purifying cast iron for foundry and other purposes, substantially as set 1
forth.
In witness whereof, I, the said James Henderson, have hereunto
set my hand and seal this Tenth day of May, in the year of our
Lord One thousand eight hundred and seventy.

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I JAMES
HENDERSON, of New York, in the United States of America, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent, bearing date the Twenty-seventh May, One
thousand eight hundred and seventy, No. 1544, did, for Herself,
Her heirs and successors, grant unto me, the said James Henderson,
Her special license that I, the said James Henderson, my executors,
administrators, and assigns, or such others as I, the said James
Henderson, my executors, administrators, or 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

page_text: 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 IMPROVEMENT IN THE PROCESS OF REFINING AND PURIFYING
CAST IRON FOR FOUNDRY AND FOR OTHER PURPOSES :
"
And whereas I, the said James Henderson, by a Complete Specification
being an instrument in writing under my hand and seal, did particularly
describe the nature of the said Invention, and in what manner the same
was to be performed, and caused the same to be filed in the Great Seal
Patent Office, with my Petition and Declaration, on the Twenty-seventh
day of May One thousand eight hundred and seventy, pursuant to the
9th Section of the Patent Law Amendment Act, 1852 :
And whereas since filing the said Specification I have ascertained that
the title and Specification may be construed to comprise other Inven-
tions beyond the application of fluorides in combination with oxides in
treating cast iron intended to be used for casting and foundry purposes,
which constitutes my present Invention, being a further Invention
arising out of the application of fluorides, combined with oxides in
treating iron in the preparation of crude iron for being made into
wrought iron or steel, which constituted a former Invention made
by me:
And whereas I am desirous of limiting my present Invention to the
application of fluorides combined with oxides in treating and preparing
cast iron for casting or foundry purposes.
NOW KNOW YE, that I, the said James Henderson, by and with the
leave of Her Majesty's Solicitor-General, and for the reasons aforesaid,
do disclaim and alter parts of the title and description of my present
Invention as contained in my said Complete Specification in manner
following:-
"
I strike out of the title of my said Invention the words " and for
other which are found in the said title and the recital thereof as
printed in page 1 of the Queen's Printers copy of my said Specification,
published in One thousand eight hundred and seventy. I also strike out
and the words "and many other uses" in line 18
the words "and other" which are found in line 10 of page 2 of the same
copy. Also after the words "or wrought iron" which occur in line 28
of page 3 of the same copy I insert the following words, "but I make

page_text: 3
no claim to such application in the processes used in preparing crude
iron for being converted into wrought iron or steel, or otherwise, than
in purifying and treating cast iron intended to be used for casting or
foundry purposes." I also strike out the words "cast or pig iron,"
and the following words down to and including the words "metallurgical
purposes," which are found in lines 33, 34, 35, 36, 37, and 38, in page
of the same Queen's Printers copy. I also strike out the words “and
other" which are found in the claiming clause in my said Specification
in line 15 of page 4 of the said Queen's Printers copy. And in order
that the effect of the said Disclaimer and Memorandum of Alteration
may be better understood, I annex hereunto a copy of the said Specifica-
tion as it will appear when so altered and amended, the preamble and
testing clause being omitted.
WHEREAS I am in possession of an Invention for "An Improvement in
the Process of Refining and Purifying Cast Iron for Foundry Purposes,"
and have petitioned Her Majesty to grant unto me, my executors,
administrators, and assigns, Her Royal Letters Patent for the same,
and have made solemn Declaration that I am the true and first Inventor
thereof.
NOW KNOW YE, that I, the said James Henderson, do hereby
declare that the following Complete Specification under my hand and
seal fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement :-
The object of this Invention is to remove from cast or pig iron silicon,
sulphur, and phosphorus, together with the required amount of carbon,
in order to improve its quality and condition for foundry purposes, and it
consists in treating such iron with fluor spar or other fluoride in com-
bination with oxides.
Various modes of carrying my improved process into practice may be
adopted, but one which I have tried with success, and which I consider
to be the best, is to reduce the fluor spar and other fluorides, and also
b
A
the oxides, to a finely divided state and mix them thoroug ly together,
and then charge them evenly over the sole or hearth of any suitable
reverberatory furnace. I prefer that the furnace should be provided
with an iron bottom arranged in a manner similar to the bottom of a

page_text: boiling or puddling furnace, or the furnace may have a wrought-iron
fettling or bottom melted upon the cast-iron bottom of such furnace.
After thus placing the combined fluorides and oxides in the furnace or
crucible, I charge ordinary cast or pig iron upon them, and when the
iron is melted it flows over the fluorides and oxides and dissolves or
melts them, whereupon their action upon the iron will be found to
remove from it in the form of vapour, or slag, or both, the silicon,
sulphur, and phosphorus, and a sufficient amount of the carbon, leaving
the resulting metal refined and very greatly improved for foundry
purposes.
In working my process it will be attended with the best results when
the average proportions of silicon, sulphur, and carbon present in the pig
or smelted iron which is produced at any particular works are first
ascertained, and when the per-centage of silicon contained in the oxides
to be used is also known. The requisite quantity of combined fluor
spar or fluorides and oxides can be easily estimated in any given case,
sufficient quantities being taken of the fluoride to remove the silicon and
silica as fluoride of silicon and of the oxides to properly act upon or
oxidize the sulphur and phosphorus and the requisite amount of carbon
in the iron. Proper proportions of these agents will generally be about
forty parts of fluor spar or other fluorides to every fourteen parts of
silicon and every thirty parts of silica by weight in the oxides, and the
proportions of the oxides should be sufficient to oxidize the sulphur and
phosphorus, and to oxidize and convert the requisite amount of carbon
into carbonic oxide or carbonic acid. But suitable quantities of the
fluorides and oxides for use in any particular case will be easily
determined by any practical chemist or metallurgist from the foregoing
instructions, and the above example is only given by way of illustration.
For ordinary foundry purposes or when good qualities of cast iron are
to be treated by this improvement hematites or magnetic iron ores may be
employed for the oxides, and when it is desired to give special strength
and hardness to the cast iron I recommend that oxides be employed
which contain either manganese or titanic, chromic, or tungstic acid.
When it is specially wished to remove sulphur from the cast iron I prefer
to use manganesic oxides with fluor spar or other fluoride or such oxides
in admixture with other oxides, and when both sulphur and phosphorus
are to be removed I generally employ oxides containing titanic acid.

page_text: I wish it to be understood that I do not limit myself to practising my
improvement in the particular apparatus or manner which I have herein
described, as it may be performed in many different modes which will
suggest themselves to iron workers from the foregoing directions.
And I may also remark that the combined fluorides and oxides may be
applied in the same manner as and if preferred at the same time with
or in connection with ordinary fluxes in any of the processes now used
for preparing crude iron to be converted into steel or wrought iron; but
I make no claim to such application in the processes used in preparing
crude iron for being converted into wrought iron or steel, or otherwise
than in purifying and treating cast iron intended to be used for casting
or foundry purposes. When however my process is practiced in any
apparatus other than a cupola or reverberatory furnace it will usually be
found desirable to heat the fluorides or oxides by any convenient means
until they become viscid before the cast iron is run in upon them.
It is obvious that when the application of the present improvement is
carried so far as to leave in the metal treated no more carbon than about
one and seven-eighths per cent. or less the product may be considered
as steel. This it is not the object of the herein specified process to
produce, as such application of combined fluorides and oxides are
covered by other Letters Patent obtained by me.
And I may also state that from the foregoing description it will be
obvious to any practical metallurgist that this process if desired may be
so performed as to remove only the silicon, sulphur, and phosphorus
from the cast-iron without substantially affecting the carbon, but I
usually prefer that more or less of the carbon shall be removed also.
Having thus made known my Invention, and shewn how the same
may be conveniently and advantageously carried into practice, I wish it
understood that I claim the herein described process of refining and
purifying cast iron for foundry purposes, substantially as set forth.
In witness whereof, I, the said James Henderson, have hereunto
set my hand and seal, this Twenty-first day of March, in the year
of our Lord One thousand eight hundred and seventy-two.
JAMES HENDERSON. (L.S.)

page_text: I hereby grant my fiat giving leave to the above-named James
Henderson to file in the Great Seal Patent Office, with the Specifica-
tion to which the same relates, the above-written Disclaimer and
Memorandum of Alteration.
Dated this Thirteenth day of April One thousand eight hundred