IMPROVE- MENTS IN THE MANUFACTURE OF IRON AND STEEL
Year: 1868

page_text: LETTERS PATENT to Charles Sanderson, of Worksop, in the County
of Nottingham, Steel Manufacturer, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF IRON AND STEEL."
Sealed the 4th August 1868, and dated the 28th February 1868.
PROVISIONAL SPECIFICATION left by the said Charles Sanderson at
the Office of the Commissioners of Patents, with his Petition, on
the 28th February 1868.
I, CHARLES SANDERSON, of Worksop, in the County of Nottingham,
Steel Manufacturer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL," to be as
follows:-
The object of this Invention is to eliminate from crude cast iron when
in a molten state such volatilizable impurities as phosphorus, sulphur,
& arsenic. This is effected by causing the molten metal in a puddling
or other suitable furnace to boil, so as to throw off. the impurities in a
gaseous form, and then oxidize such impurities by means of a current
or blast of air which is carried into the furnace above the surface of the

page_text: molten metal, and which when passing through will carry the gaseous
impurities out of the furnace and prevent them from re-combining with
the iron. The current or blast of air may be produced and conducted
through the furnace either by opening the damper or by forcing in a
blast by means of a fan, blower, or other suitable mechanical device.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said Charles Sanderson in the Great Seal Patent Office
on the 28th August 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
SANDERSON, of Worksop, in the County of Nottingham, Steel Manu-
facturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-eighth day of February, in the
year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-first year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Charles Sanderson, Her special licence
that I, the said Charles Sanderson, my executors, administrators, and
assigns, or such others as I, the said Charles Sanderson, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time, and 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 "IMPROVEMENTS IN
THE MANUFACTURE OF IRON AND STEEL," upon the condition (amongst
others) that I, the said Charles Sanderson, my executors or adminis-
trators, 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 Charles Sanderson, do hereby declare
the nature of my 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 Drawing hereunto

page_text: mereon that is to
say)
:-
The object of my Invention of "Improvements in the Manufacture
of Iron and Steel" is to eliminate from crude cast iron the phosphorus,
sulphur, and other volatilizable impurities contained therein, so that
the refined cast iron, may be converted into steel or wrought iron of
good quality.
Iron has usually been purified from phosphorus and various other
impurities by mixing with it when in a molten state certain chemical®
substances which are supposed to have a strong affinity for such
impurities, or with which these substances will combine with avidity,
and will form compounds which may be readily separated from the
metal. These processes are found to act but very imperfectly, and I
have discovered that during the violent ebullition that takes place
when sulphate of iron or other substances which are capable of dis-
engaging oxygen, when decomposed, are added to the fluid metal in
the puddling or other furnace a part of the oxygen of the sulphate of
iron combines with the carbon of the crude metal, while phosphorus
is also evolved, and by combining with another portion of the oxygen
of the sulphate of iron becomes converted into phosphoric acid in a
gaseous form, in which form it may be easily driven out of the furnace.
In carrying out my Invention I proceed as follows:-The pig irou
is melted on the bed of a puddling or other furnace at a high heat,
with the damper so regulated as to get the whole of the metal into a
fluid state as soon as possible. I then begin to charge in sulphate of
iron or other suitable oxydizing substance, and then rabble the iron,
and at the same time the puddler or attendant must draw the damper
wide and cause a draught or current of air to pass through the furnace.
The fire must also be pushed on, in order to greatly increase the heat.
Whilst the metal boils violently (owing to the rapid formation of
carbonic oxide gas and phosphoric acid in the body of the melted
metal) the gas will liberate itself, and with it the phosphorus sulphur
and other volatilizable and oxydizable impurities. By these impurities
becoming oxydized (principally by combining with the oxygen which is
evolved by the decomposition of the sulphate of iron or other analagous
substance which is charged into the fluid metal, and partly by means
of the oxydizing draught which is passing through the furnace) they
will be brought into a gaseous state, and will by the strong draught:

page_text: be at once. carried out of the furnace through the flue and up the
chimney stack, and in this way-these gaseous impurities are got com-
pletely rid of out of the furnace, and cannot return.
It will be understood from the foregoing description that the phos-
phoric acid and other impurities are thus got rid of (not by entering
into combination with any solid re-active agent charged into the furnace
as heretofore, and forming new solid compounds, which remain in tho
furnace); but on the contrary, by forming gaseous compounds which are
capable of being carried bodily away whilst in such gaseous state, such
carrying or driving off of the gaseous impurities being effected by the
strong draught and high oxydizing heat of the furnace, and not being
allowed to remain until they become deoxydized again, in which state
they would re-enter the iron. The blast of air may be heated, and if
required, may be forced by any suitable blowing apparatus through the
furnace at the proper time for carrying off the gaseous impurities when
they have been forced out of the molten metal by the violent ebullition
to which the latter has been subjected, as above described.
In the accompanying Drawings I have shewn longitudinal sectional
views of two puddling furnaces suitably arranged for carrying out my
Invention.
In Fig. 1a is the hearth of the furnace containing the molten metal;
6 is the fire-place; c, the bridge; d, the working door; e, a set of
twyers or open-ended pipes for admitting an oxydizing blast to the
body of the furnace above the molten metal when required. These
twyers or pipes, of which there may be any convenient number, are
screwed in or attached to a box embedded in the fire-bridge, and con-
nected by a pipe e' with a blowing machine or fan not shewn in the
Drawing. In Fig. 2, which is also a longitudinal section of a puddling
furnace the blowing tubes or twyers e, e, are placed just below the
crown, dome, or roof of the furnace, so as to cause the blast of air to
pass over the fire in the fire-place b, and from thence over the surface
of the molten metal. One blowing machine or fan will serve for several
furnaces, as for the purposes of my Invention the blast or draught is
only required for a short time, and the air pipes c' of each furnace
must be provided with a stop-cock or valve, whereby the air blast may
be regulated and let on or cut off when required.
Having now described my Invention of improvements in the
manufacture of iron and steel, and having explained the manner

page_text: of carrying the same into effect, I claim as my Invention the mode
herein set forth of eliminating from molten cast iron, and carrying or
driving off therefrom (in a gaseous state) the volatilizable impuritics
contained therein.
In witness whereof, I, the said Charles Sanderson, have hereunto
set my hand and seal, the Twentieth day of August, in the year
of our Lord One thousand eight hundred and sixty-eight.
Witness,
SUTTON MARSHALL SIMPSON,
23, Lower Parade,
Leamington,
CHARLES SANDERSON. (L.S.)
Warwickshire.