IMPROVE- MENTS IN THE, MANUFACTURE OF IRON AND STEEL, AND IN APPARATUS FOR MOULDING SAME
Year: 1881

page_text: LETTERS PATENT to John Albert Huggett, of 132, Finborough Road,
Kensington, in the County of Middlesex, for an Invention of "IMPROVE-
MENTS IN THE, MANUFACTURE OF IRON AND STEEL, AND IN APPARATUS FOR
MOULDING SAME "
"
.. a
PROVISIONAL SPECIFICATION left by the said John Albert Huggett at the
Office of the Commissioners of Patents on the 12th January 1881.
JOHN ALBERT HUGGETT, of 132, Finborough Road, Kensington, in the County
of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL, AND
IN APPARATUS FOR MOULDING SAME.”
This Invention has for its object improvements in the manufacture of iron and
steel.
At the present time large quantities of steel or iron are produced by the Siemens
Martin process, and like processes, in which a bath of cast iron is raised. to a very
high temperature in. a regenerative or other suitable furnace, and being treated
usually with additions of iron scrap and oxide is brought to a steely condition,.in
which state the molten metal is run out of the furnace and is received into moulds
to form ingots.
i
Now I have discovered that this process, can be worked more advantageously.
than heretofore by employing steam to blow the metal whilst it is contained molten
in the furnace. I introduce the steam. by means of a small iron pipe connected
with a.steam boiler by a a flexible connection. The end of this pipe I immerss
for some inches beneath the surface of the metal, and in an inclined direction, so
that the steam issuing from the pipe may mechanically promote circulation at
the same time that by its chemical action it causes a rapid rise of temperature.
☑
The advantages which I obtain are a great saving in the time required to bring
the metal bath to the state and temperature suitable for running the metal out of
the furnace into the ingot moulds, a more complete separation of the sulphur.
and silicon than can otherwise be conveniently obtained, and the removal of the
silicon when desired at an earlier stage than it otherwise would be, so leaving the
steel with a high proportion of carbon, whilst the separation of the silicon has
already been effectually obtained.
In order to obtain sound ingots I cause the metal to enter the mould at the
bottom, and I close the top of the ingot mould with a loosely fitting cast iron
stopper. Through the stopper there is a small hole. Instantly when the mould.
has become full of metal, and when the metal is close up: to but not in, contact,
with the under side of the plug I admit a stream. of water through the hole in the
plug directly on to the top of, the molten metal.in.the mould.. I allow the water
to run until the ingot is set..

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Albert Huggett in the Great Seal Patent Office on the
11th July 1881.
"
JOHN ALBERT HUGGETT, of 132, Finborough Road, Kensington, in the County
of Middlesex. . IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL, AND
IN APPARATUS FOR MOULDING SAME."
This Invention has for its object improvements in the manufacture of iron and
steel.
At the present time large quantities of steel or iron are produced by the Siemens
Martin process, and like processes, in which a bath of cast iron is raised to a very
high temperature. in a regenerative or other suitable furnace, and being treated
usually with additions of iron scrap and oxide is brought to a steely condition, in
which state the molten metal is run out of the furnace and is received into moulds
to form ingots.
Now I have discovered that this process can be worked more advantageously
than heretofore by employing steam to blow the metal whilst it is contained
molten in the furnace. I introduce the steam' by means of a small iron pipe
connected with a steam boiler by a flexible connection. The end of this pipe I
immerse for some inches beneath the surface of the metal and in an inclined
direction, so that the steam issuing from the pipe may mechanically promote
circulation at the same time that by its chemical action it causes a rapid rise of
temperature.
The advantages which I obtain are a great saving in the time required to bring
the metal bath to the state and temperature suitable for running the metal out of
the furnace into the ingot moulds, a more complete separation of the sulphur
and silicon than can otherwise be conveniently obtained, and the removal of the
silicon when desired at an earlier stage than it otherwise would be, so leaving the
steel with a high proportion of carbon, whilst the separation of the silicon has
already been effectually obtained.
In the practice of my Invention I place as usual in the Siemens Martin furnace
the pig iron of suitable quality which I intend to employ, and the scrap which I
intend to work up with it; the relative quantities may be much varied according
to convenience, as is well understood.
As soon as the metal is for the most part melted I at once apply the blow pipe,
which is a thin iron pipe about half inch internal diameter. This pipe is connected
by any suitable flexible connection with a boiler in which is steam at a pressure of,
say, 40 to 60 pounds; the amount of pressure at any rate within these limits is
unimportant; the end of the blow pipe is introduced into the furnace by the centre
door (three doors are usually provided to these furnaces upon the working side),
and its end is made to dip into the metal nearly at the centre. of the molten bath.
The jet of steam drives the metal before it towards the opposite side of the furnace
and sets up a double circulation; the stream receding from the jet impinges upon
the opposite side of the bath and divides, sweeping round the two ends of the bath
and again approaching the jet. In addition to this mechanical operation of the
jet in causing circulation amongst the contents of the bath it produces intense
chemical action and a rapid rise in temperature, so that if the whole of the metal
was not melted when, the jet was applied it becomes so in a very short time.
Directly the blow pipe is applied the first portion of the oxide of iron. (hoematite
ore) to be used in the process is thrown in. This affords some protection to the

page_text: iron blow pipe, which however notwithstanding the rush of steam through it is
by degrees melted away so that several feet of pipe will be consumed in a single
operation. I continue the blow in this manner for about an hour and a half or
two hours until the action ceases to be energetic, and by the appearance of samples
I judge that but little silicon remains combined with the metal. During this blow
the oxide ore is added from time to time until most if not all of the usual and
necessary quantity is in.
After the blow pipe has been removed I leave the charge in the furnace for a
considerable time to effect the proper reduction of the carbon in combination with
the metal. The percentage of carbon in the metal will be found to run rapidly
down, and it may be hastened by the addition of further small quantities of
oxide ore.
The steel which I have usually required is of a very soft and ductile description,
and for this quality I leave the metal in the furnace for from two to three hours
after the blow pipe is removed, but for more highly carbonised qualities so long a
time will not be required. As the steel gets near to the desired state I draw
samples and test them, and when the proper point is arrived at I tap the metal out
of the furnace into ingot moulds in the usual manner.
When using my process I have found it advisable to arch up the roof of
the furnace in the centre so as to raise some what the part of the roof which
is immediately over the end of the blow pipe when in use; for the steam
causes some splashing of the fused oxide, and the roof, if not raised, would be
corroded.
I have experimented with tubes of various non metallic materials, but have found
none to stand in the furnace.
In the use of this process I have found the steel produced to be very regular in
quality. Sulphur is eliminated by the process when the materials employed
contain this impurity.
"
My Provisional Specification contains the following paragraph:-
"In order to obtain sound ingots I cause the metal to enter the mould at the
bottom, and I close the top of the ingot mould with a loosely fitting cast iron.
stopper. Through the stopper there is a small hole. Instantly when the mould
"has become full of metal, aud when the metal is close up to but not in contact
with the under side of the plug, I admit a stream of water through the
". hole in the plug directly on to the top of the molten metal in the mould. I allow
" the water to run until the ingot is set."
In respect to the means for casting steel into ingots which is here described I
desire to make no claim; I have practised the method for some time and with
considerable advantage, but I have found also that the introduction of water into.
the mould in the manner described occasionally, although rarely, gives rise to
dangerous explosions. For this reason I do not recommend the practice.
I would here remark that I am aware that it has before been proposed to blow metal
with steam in various ways, and I make no general claim to blowing metal with
steam. My Invention is essentially an improvement upon the process commonly
known as the Siemens Martin, a process in which molten iron is decarburised in a
furnace by additions of oxide in such manner that a fluid bath of steely metal is
obtained, and in which the metal is brought to a state to be run out of the furnace
into moulds and so formed into malleable ingots.
Again, although I am not aware that in the Siemens Martin process the metal
has ever been blown with steam or any means devised by which steam could be
usefully applied in this process, nevertheless. I desire to contine my claim to that
which by practical experience I know to be useful, and
I claim the application of steam to the bath of molten metal by means of an
iron pipe directed obliquely downwards on to the metal and through the oxide
floating upon its surface, so that the steam is brought into contact with the metal
and circulation in the bath maintained, and so that the silicon is first climinated

page_text: from the metal; the carbon which remains still in excess being finally brought to
the desired point after the steam pipe has been removed.
In witness whereof, I, the said John Albert Huggett, have hereunto set my
hand and seal, this Eighth day of July, in the year of our Lord One
thousand eight hundred and eighty one.