IMPROVEMENTS IN THE TREATMENT OF FUSED STEEL AND IRON, AND APPARATUS THEREFOR
Year: 1874

page_text: LETTERS PATENT to Perceval Moses Parsons, of Melbourne House,
Blackheath, in the County of Kent, Civil Engineer, for the In-
vention of "IMPROVEMENTS IN THE TREATMENT OF FUSED STEEL AND IRON,
AND APPARATUS THEREFOR."
Sealed the 4th September 1874, and dated the 11th March 1874.
PROVISIONAL SPECIFICATION left by the said Perceval Moses Parsons
at the Office of the Commissioners of Patents, with his Petition,
on the 11th March 1874.
I, PERCEVAL MOSES PARSONS, of Melbourne House, Blackheath, in
the County of Kent, Civil Engineer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE TREATMENT OF FUSED STEEL
AND IRON, AND APPARATUS THEREFOR," to be as follows:-
:-
In the manufacture of cast steel or cast, malleable, or steely iron by
processes now in use the ingots and other articles cast therefrom are
liable to be cellular and spongy in consequence of air or gases being
imprisoned in the metal, and this is particularly the case in metal pro-

page_text: duced by the Bessemer process, according to which decarbonization is
effected by blowing air or gases into the molten metal.
The object of my Invention is to extract from the fused metal the air
or gases which are held in suspension, solution, or combination therein,
or which may be evolved therefrom, so as to improve the quality of the
metal, and to render it sound and homogeneous when it solidifies by
preventing the formation of cells or sponginess. For this purpose when
the metal is in a fluid state I place it in a closed vessel, from which I
exhaust the air by means of an air pump, or by opening a communi-
cation with a chamber in which a vacuum or partial vacuum is
maintained.
For the purpose of treating in this manner metal produced by the
Bessemer process the converting vessel itself may be employed as the
exhausting vessel, a removeable cap being fitted over the mouth of the
same, and the air being exhausted through the tuyeres after canting the
vessel, or through a separate pipe, in any convenient position.
For treating metal produced by any other processes, as well as by the
Bessemer process, the casting ladle may be employed for exhaustion by
fitting to it a removeable cap or cover, and closing the tap hole and
other apertures, so as to render the ladle air-tight for the time..
In cases where an ingot mould is sufficiently large to contain such a
mass of metal as will remain for a sufficient time fluid it may be closed
air-tight by a removeable cover after the metal has been poured into it,
and subjected to exhaustion. Or a separate air-tight vessel with a
removeable cover may be provided, in which the casting ladle or the
ingot mould containing the molten metal may be placed, and the air
may be exhausted from the vessel while the metal is in a fluid or
molten state by any of the well-known means for producing a vacuum
or partial vacuum.
7

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said Perceval Moses Parsons in the Great Seal Patent
Office on the 10th September 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PERCEVAL
MOSES PARSONS, of Melbourne House, Blackheath, in the County of
Kent, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of March, in the year
of our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Perceval Moses Parsons, Her special
license that I, the said Perceval Moses Parsons, my executors, admini-
strators, and assigns, or such others as I, the said Perceval Moses Parsons,
my executors, administrators, and 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 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 TREATMENT OF FUSED STEEL AND IRON, AND IN APPARATUS
THEREFOR," upon the condition (amongst others) that I, the said Perceval
Moses Parsons, 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 calender
months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Perceval Moses Parsons, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, reference being had to the accom-
panying Sheet of Drawings, and to the figures and letters marked
thereon, that is to say :-
In the manufacture of cast steel or cast, malleable, or steely iron by
processes now in use the ingots and other articles cast therefrom are
liable to be cellular and spongy in consequence of air or gases being

page_text: imprisoned in the metal; and this is particularly the case in metal pro-
duced by the Bessemer process, according to which decarburization is
effected by blowing air or gases into the molten metal.
The object of my Invention is to extract from the fused metal the air
or gases which are held in suspension, solution, or combination therein, 5
or which may be evolved therefrom, so as to improve the quality of the
metal, and to render it sound and homogeneous, when it solidifies by
preventing the formation of cells or sponginess. For this purpose when
the metal is in a fluid state I place it in a closed vessel, from which I
exhaust the air by means of an air pump, or by opening a communi- 1
cation with a chamber in which a vacuum or partial vacuum is
maintained.
For the purpose of treating in this manner metal produced by the
Bessemer process the converting vessel itself may be employed as the
exhausting vessel, a removeable cap being fitted over the mouth of the 1
'same, and the air being exhausted through the tuyeres after canting the
Vessel, or through a separate pipe, in any convenient position. .
For treating the metal produced by any other processes, as well as by
the Bessener process, the casting ladle may be employed for exhaustion by
fitting to it a removeable cover or cap, and closing the tap hole.and other 2
apertures, so as to render the ladle air-tight for the time.
In some cases where an ingot or other mould is sufficiently large to
contain such a mass of metal as will remain for a sufficient time fluid it
may be closed air-tight by a removeable cover after the metal has becn
poured into it and subjected to exhaustion. Or a separate air-tight 2
vessel with a removeable cover may be provided, in which the casting
ladle or the ingot or other mould containing the molten metal may be
placed, and the air may be exhausted from the vessel while the metal is
in a fluid or molten state by any of the well-known means for producing
a vacuum or partial vacuum.
A like treatment is applicable to ordinary anot iron. when it in

page_text: shews a vertical section of the converter, and Fig. 2 shews à part plan
of the same with the cap in horizontal section.
b
For closing the mouth of the converter a cap a of cast or wrought
iron is provided suspended by hinge b attached to one side of the con-
verter. A flange c. properly faced is fastened around the neck of the
converter against which the cap a is made to fit, an air-tight joint being
insured by means of a ring of soft metal or other suitable packing & in
the face of the cap. When the cap is not required to cover the mouth
of the converter it is swung round on the hinge into the position shewn
by the dotted lines in Fig. 2, and maintained in that position by a pin e,
or other temporary fastening. The hinge may be dispensed with, the
cap being moved bodily by a small crane fixed in a convenient position.
In the construction of the converting vessel itself when my before-
described process is intended to be adopted precautions will have to
taken to render it air-tight, and to enable it to bear the external
pressure of the atmosphere when a vacuum is maintained within it.
It should therefore be made of sufficiently strong plates with the rivets
put closer together than is usually the case in constructing converting
vessels for the ordinary process, and the joints should be caulked. The
tuyere box should also be made air-tight, and the joint between it and
the bottom plate of the converter made good at f, Fig. 1; and in order
to provide escape for any leakage of air at the tuyeres when the blast is
on a cock g, Fig. 1, may be fixed in the tuyere box communicating witli
the space between the tuyere box and the bottom plate of the converter,
as shewn, which cock is kept open when the blast is on, and closed when
the vacuum is being produced in the vessel. The converting vessel
being thus prepared after the charge of metal has been converted the
vessel is turned down, and the cap a is closed down upon the flange c',
the joint being rendered air-tight simply by the weight of the cap, and
the pressure of the atmosphere when the vacuum is produced within the
converter; or when necessary the cap may be secured by clamp
screws. The air is then exhausted from the converter through the
tuycres and blast pipe by the blowing engines, which will in this case
have to be adapted to exhaust from, as well as to force air into the con-
verter; or a separate air pump may be used, the pipe from which
provided with a stop-cock may be attached to. the blast pipe near the
trunnion, or it may be made to enter a stuffing box, and be carried
round and onter the converter through its upper side. In this case it

page_text: will be desirable to provide an air tight shut-off valve in the blast pipo
near to the converter in order to obviate the inconvenience of leakage
which might take place in any of the joints of the blast pipe or valves
in the distributing box. Or the air may be exhausted by opening a
communication from the interior of the converter to a vessel in which a
vacuum has been produced by condensation of steam, the requisite stop-
cocks and valves being provided for this purpose. When the blowing
engines are used to exhaust the air from the converter care will have to
be taken that all the joints of the pipes are good, and that the shut-off
valves are accurately faced and fitted, so as to work air-tight.
When by the exhaustion of the air from the converting vessel, as
above described, the air or gases have been extracted from the fused
metal atmospheric pressure is again admitted by means of a cock on the
exhaust pipe or on the cap a, and the cap is turned back into the
position shewn in Fig. 2, or.removed bodily, so as to allow the metal to
be poured out of the converting vessel.
Fig. 3 shews an arrangement for extracting the air and gases from
the fused metal when in a casting ladle, as applied to a Bessemer con-
verting pit, but which is also applicable for treating steel produced by
other than the Bessemer process, or for treating cast iron. a is part of
a casting crane usually employed, carrying the casting ladle 6, which in
addition to the ordinary trunnions has two additional trunnions c above
these.
At any convenient part of the back part of the pit adjoining the wall
usually crected between it and the melting house and under the sweep
of the casting crane an air-tight vessel of cast or wrought iron d is sunk
into the floor. This vessel, for the sake of simplicity, is made of a
cylindrical form large enough to take in the ladle with its trunnions,
worm wheel, rod for opening and closing the tapping hole and other
appurtenances, and the irregular space around and under the ladle and
its appurtenances may be filled in with fire-brick or other refractory
material n, so as to diminish the air space as much as possible, and to
protect the vessel from injury in case of molten metal being accidentally
spilled in it. The vessel d is provided with a lid e, which may
hinged to the vessel and counterbalanced, as shewn in Fig. 3. The
flanges of the vessel and lid are properly faced, and the joint between
them is rendered air-tight when the lid is closed by a ring 9 of soft
metal or other suitable packing. A hydraulic cylinder is fixed ver-
be

page_text: tically over the vessel d, and its piston rod is attached to a cross
head and links i suited to take the upper trunnions c of the ladle.
The ladle 6 when it is charged with the fused steel or metal is brought
by the crane to the position shewn in Fig. 3. The links being then.
engaged with the upper t
trunnions c the under side of the piston in the
hydraulic cylinder is subjected to pressure, and the ladle is thus raised
off the crane, as indicated by the dotted lines 63.. The crane being then
moved out of the way the ladle is lowered into the vessel d, as indicated
by the dotted lines 6³, the links are disengaged and raised, and the
lide is closed down, its joint to the vessel d being made good by its
weight and the atmospheric pressure on it, or it may be by means of
clamp screws. The air and gases are then extracted from the vessel by a
pipe communicating with a pump or condenser, and when the vessel
and its contents have been sufficiently exhausted air is admitted again
by a cock or valve m. The lid is then opened; the ladle is raised by the
action of the hydraulic cylinder, and placed upon the crane whereby it
is moved to the place where its contents are poured out into the.desired
moulds: The form and dimensions of the exhausting vessel d may be
adapted to the reception of an ingot or other mould containing a
sufficient body of metal to remain fluid during exhaustion. When the
exhaustion is applied to the ladle itself the ladle may be provided with a
cover such as a, Fig. 1, which may be suspended by a lever and counter-
balanced, so that it can be lowered on to the ladle or raised off it as
required, the lid being made to communicate with the air pump or
other exhausting apparatus by a pipe jointed so as to allow for the
movement of the lid.
When an air pump is employed for exhaustion its valves and fittings.
should be of metal or material capable of withstanding the high tempera-
ture of the air and gases drawn by it from the molten metals; and in
order to reduce the temperature of the exhaust the pipe leading to the
pump may be passed through water.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I would have it understood that I
make no claim to any method of filling ingot or other moulds with
molten metal by extracting the air from the upper parts of such moulds,
and admitting the molten metal at the bottoms thereof; but I do
claim,―
First The method substantially as hercin described of rendering steal

page_text: and cast iron round and homogeneous and preventing the formation of.
cells or spongyness in castings of such materials by subjecting the metal,
while in a molten state and before being cast, to exhaustion, and thereby
extracting from the metal air or gases suspended in it.
Second. Adapting for the purpose above referred to the converting
vessels such as are used in 'the Bessemer process, substantially in the
manner herein described.
Third. The use for the purpose above referred to of a casting ladle
closed by a removeable cover or of an exhaust vessel in which a casting
ladle or an ingot or other mould is placed while its contents are sub- 1
jected to the action of the exhaust, substantially as herein described.
In witness whereof, I, the said Perceval Moses Parsons, have
hereunto set my hand and seal, this Ninth day of September,
in the year of our Lord One thousand eight hundred and seventy-
.four.
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