IMPROVE- MENTS IN THE MANUFACTURE OF STEEL AND HOMOGENEOUS IRON
Year: 1865

page_text: LETTERS PATENT to Robert Mushet, of Belgrave House, Cheltenham,
in the County of Gloucester, Metallurgist, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF STEEL AND HOMOGENEOUS IRON."
Sealed the 18th August 1865, and dated the 9th March 1865.
PROVISIONAL SPECIFICATION left by the said Robert Mushet at the
Office of the Commissioners of Patents, with his Petition, on the 9th
March 1865.
I, ROBERT MUSHET, of Belgrave House, Cheltenham, in the County of
Gloucester, Metallurgist, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN THE MANUFACTURE OF STEEL AND HOMOGENEOUS IRON,"
to be as follows:-
When melted pig iron or cast iron is treated by the decarbonizing process,
commonly called the pneumatic process, for the purpose of converting the said
pig or cast iron into homogeneous iron or steel, it is the practice at the close
of the pneumatic operation to introduce into the decarbonized pig iron or cast
iron a quantity of spiegel eisen or manganesic pig iron in order to restore the

page_text: requisite amount of carbon to the said decarbonized pig iron or cast iron, the
carbon having been too far exhausted or wholly removed by the said pneumatic
process. Now I have found that when pneumatized decarbonized cast iron
contaminated with sulphur is mixed with spiegel eisen, and the carbon and
manganese of the said spiegel eisen are eliminated by means of the pneumatic
blast being again turned on, and the carbon and manganese thereby expelled,
a portion of the sulphur contained in the said pneumatized cast iron is eliminated
with the carbon and manganese, and by adding successive doses of spiegel eisen
to the pneumatized cast iron, and then eliminating the carbon and manganese
by means of the pneumatic blast, the pneumatized cast iron may be purified
or partially purified from sulphur. Also when pneumatized decarbonized cast
iron is contaminated with both sulphur and phosphorus then if spiegel eisen and
titanic pig metal are added to and mixed with the said pneumatized cast iron,
the elimination of the carbon, manganese, and titanium of the said spiegel eisen
and titanic pig metal by the turning on of the pneumatic blast carries off a
portion of both the sulphur and the phosphorus, and by similar repeated
additions and eliminations both the sulphur and phosphorus may be partially
or wholly got rid of.
°
At the close of the operation I add as much spiegel eisen in the usual
manner as is requisite to recarbonise the pneumatized cast iron to the extent
desired, but this addition of spiegel eisen for the purpose of permanently
restoring carbon to the iron forms no part of my Invention. Spiegel eisen is
a manganesic cast iron made in Rhenish Prussia, and is well known in commerce,
and I do not therefore think it necessary to describe it; titanic pig metal is
best prepared by smelting hematite iron ores in a blast furnace with from five
to. ten per centum of its weight of ilmenite. Ilmenite is a rich double ore of
titanium and iron, and is found in abundance at Egersund in Norway, and
elsewhere.
The furnaces I employ are those in ordinary use for treating melted pig iron
or cast iron by the pneumatic process.
In carrying my Invention into effect, I proceed in the following manner:
When the melted pig iron or cast iron which has been decarbonized in the
pneumatic converter and mixed with spiegel eisen is injuriously contaminated
with sulphur, I turn on the pneumatic blast, and thereby eliminate by oxida-
tion the carbon and metallic manganese which have been added to the
decarbonized pig iron or cast iron in the shape of spiegel eisen. I then with-
draw the blast, and add a second dose or quantity of spiegel eisen, either in the
melted state or in heated lumps, or even in the cold state, but preferably in

page_text: heated lumps, or in the melted state. The lumps thus added are speedily melted,
dissolved, and combined with the melted pneumatized iron.
If after this second addition of spiegel eisen to the pneumatized pig iron or
cast iron the latter is still injuriously contaminated with sulphur, I again turn on
the pneumatic blast and eliminate the carbon and manganese of the second dose
of spiegel eisen added, and so on until the purification is complete. To facilitate
the elimination of both sulphur and phosphorus I heat lumps or pieces of
titanic pig metal and introduce them together with spiegel eisen into the
pneumatized pig or cast iron, wherein the said lumps or pieces of titanic pig
metal are speedily melted and dissolved. The titanic pig metal may be intro-
duced into the melted pneumatized cast iron or pig iron in the melted state
or in the cold state, but I prefer introducing it in heated lumps or pieces so
that it may be fused in contact with the pneumatized iron. I then turn on
the pneumatic blast and eliminate the titanium and carbon of the titanic pig
metal, and the manganese and carbon of the spiegel eisen thus added. The
quantity of spiegel eisen which I add at each successive operation may be
varied, but I find that from twenty pounds to one hundred pounds of spiegel
eisen to every ton of melted pneumatized cast iron affords very good results.
The quantity of titanic pig metal added at each successive operation may be
varied, but I find some twenty pounds to one hundred pounds of heated
titanic pig metal to every ton of melted pneumatized cast iron affords
excellent results.
I sometimes add repeated doses of spiegel eisen to the pneumatized iron
without any addition of titanic pig metal, especially when sulphur chiefly is
believed to be present in the said melted pneumatized cast iron, but when
phosphorus also is supposed or is found to be present, I add both spiegel eisen
and titanic pig metal to the said pneumatized cast iron. But the manufacture
must be guided by circumstances, and the nature of the pig iron or cast iron
on which he is operating by means of the pneumatic process.
The essence of my Invention consists in refining or purifying melted pneu-
matized pig iron or cast iron by the joint action of the pneumatic blast, and
that of the successive eliminations by means of the said pneumatic blast of the
carbon and manganese or of the carbon, manganese, and titanium of repeated
doses of spiegel eisen or of spiegel eisen and titanic pig metal jointly added to
melted pneumatized decarbonized pig iron or cast iron.
"

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Mushet in the Great Seal Patent Office on the
23rd August 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
MUSHET, of Belgrave House, Cheltenham, in the County of Gloucester,
Metallurgist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of March, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Robert Mushet, Her special licence that I, the said Robert Mushet,
my executors, administrators, and assigns, or such others as I, the said
Robert Mushet, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there-
after 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 "IMPROVE-
MENTS IN THE MANUFACTURE OF STEEL AND HOMOGENEOUS IRON," upon the con-
dition (amongst others) that I, the said Robert Mushet, 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 immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Robert Mushet, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
When melted pig iron or cast iron is treated by the pneumatic process for
the purpose of converting the said pig or cast iron into steel or homogeneous
iron, it is the practice at the close of the pneumatic operation to introduce into
the molten decarbonised pig iron or cast iron a quantity of spiegel eisen or
manganesic pig iron in order to restore the requisite amount of carbon to the
Baid decarbonized pig iron or cast iron, the said carbon having been too far
extracted or wholly removed by the first pneumatic operation or process. Now
I have found that when pneumatized, decarbonized cast iron, contaminated

page_text: with sulphur is mixed with spiegel eisen, and the carbon and manganese of the
said spiegel eisen are eliminated by means of the pneumatic blast being again
turned on, and the carbon and manganese thereby expelled, a portion of the
sulphur contained in the said pneumatized cast iron is eliminated with the
carbon and manganese, and adding successive doses of spiegel eisen to the
pneumatized cast iron, and then eliminating the carbon and manganese by
means of the pneumatic blast, the pneumatized cast iron may be purified or
partially purified from sulphur. Also when pneumatized decarbonized cast
iron is contaminated with both sulphur and phosphorus, then if spiegel eisen,
and titanic pig metal are added to and mixed with the said pneumatized cast
iron the elimination of the carbon, manganese, and titanium of the said spiegel
eisen and titanic pig metal by the turning on of the pneumatic blast carries
off a portion of both the sulphur and phosphorus, and by similar repeated
additions and eliminations both the sulphur and phosphorus may be partially
or wholly got rid of.
At the close of the operation I a:ld as much spiegel eisen in the usual manner
as is requisite to recarbonise the pneumatized cast iron to the extent desired,
but this addition of spiegel eisen for the purpose of permanently restoring
carbon to the iron forms no part of my Invention. Spiegel eisen is a man-
ganesic cast iron made in Rhenish Prussia and is well known in commerce,
and I do not therefore think it necessary to describe it. Titanic pig metal is best
prepared by smelting hematite iron ores in a blast furnace with from five to
Ilmenite is a rich double ore of
ten per centum of its weight of ilmenite.
titanium and iron, and is found in abundance near Egersund in Norway, and
elsewhere.
The furnaces I employ are those in ordinary use for treating melted pig iron
or cast iron by the pneumatic process.
:
In carrying my Invention into effect I proceed in the following manner :-
When the melted pig iron or cast iron which has been decarbonized in the
pneumatic converter and mixed with spiegel eisen is injuriously contaminated
with sulphur, I turn on the pneumatic blast and thereby eliminate by oxida-
tion the carbon and inetallic manganese which have been added to the
decarbonized pig iron or cast iron in the shape of spiegel eisen. I then with-
draw the blast, and add a second dose or quantity of spiegel eisen either in the
melted state, or in heated lumps, or even in the cold state, but preferably in
heated lumps or in the melted state. The lumps thus added are speedily
melted, dissolved, and combined with the melted pueumatized iron.
If after this second addition of spiegel eisen to the molten pneumatized pig

page_text: iron or cast iron the latter is still injuriously contaminated with sulphur, I
again apply the pneumatic blast and eliminate the carbon and manganese of
the second dose of spiegel eisen added, and so on until the purification of the
molten pneumatised iron is complete. To facilitate the elimination of both
sulphur and phosphorus I heat lamps or pieces of titanic pig metal and intro-
duce them together with spiegel eisen into the pneumatized pig or cast iron,
wherein the said lumps or pieces of titanic pig metal are speedily melted and
dissolved. The titanic pig metal may be introduced into the melted pneumatized
cast iron or pig iron in the melted state or in the cold state, but I prefer
introducing it in heated lumps or pieces so that it may be fused by contact with
the pneumatized iron. I then turn on the pneumatic blast, and eliminate the
titanium and carbon of the titanic pig metal and the manganese and carbon of
the spiegel eisen thus added. The quantity of spiegel eisen which I add at
each successive operation may be varied, but I find that from twenty pounds
to one hundred pounds of spiegel eisen to every ton of melted pneumatized cast
iron affords very good results. The quantity of titanic pig metal added at each
successive operation may be varied, but I find from twenty pounds to one
hundred pounds of heated titanic pig metal to every ton of melted pneu-
matized cast iron affords excellent results.
I sometimes add repeated doses of spiegel eisen to the pneumatized iron
without any addition of titanic pig metal, especially when sulphur chiefly is
believed to be present in the said melted.pneumatized cast iron, but when
phosphorus also is supposed or is known to be present, I add both spiegel eisen
and titanic pig metal to the said pneumatized cast iron. But the manufacturer
must be guided by circumstances and the nature of the pig iron or cast iron
on which he is operating by means of the pneumatic process. The furnaces,
vessels, and other appliances which I employ in carrying my Invention into
effect, are such as are ordinarily employed in the manufacture of steel and
homogeneous iron, and I therefore do not consider it necessary to describe
the same.
By means of my Invention steel and homogeneous iron of good quality may
be made by the pneumatic process from pig or cast iron, so largely contaminated
with sulphur or phosphorus, or both, as to be incapable of yielding steel or
homogeneous iron of good quality by the pneumatic process as ordinarily
conducted.
The essence of my Invention consists in refining or purifying melted pneu-
matized pig or cast iron in the course of converting the same into steel or
homogeneous iron by the joint alternating action of the pneumatic blast and

page_text: successive additions of spiegel eisen or spiegel eisen and titanic pig metal, each
elimination of the carbon and manganese of the spiegel eisen by the pneumatic
blast when spiegel eisen alone is used, being accompanied by the elimination
of the sulphur, or of a portion of the sulphur which may be contained in the
pig or cast iron operated upon, and each elimination of the carbon, manganese,
and titanium by the pneumatic blast when spiegel eisen and titanic pig metal
are used, being accompanied by the elimination of the sulphur and phosphorus,
or of a portion of the sulphur and phosphorus which may be contained in the
pig metal operated upon.
In witness whereof, I, the said Robert Mushet, have hereunto set my
hand and seal, this Eleventh day of August, in the year of our Lord
Oue thousand eight hundred and sixty-five.
Witness
L. M. MUSHET,
Cheltenham.
ROBERT MUSHET. (L.S.)