AN IM- BRANDMENT IN THE PUDDLING AND REFINING OF IRON
Year: 1856

page_text: LETTERS PATENT to George Parry, of the Ebbw Vale Iron Works, in the
County of Monmouth, Furnace Manager, for the Invention of "AN IM-
BRANDMENT IN THE PUDDLING AND REFINING OF IRON."
Sealed the 25th July 1856, and dated the 26th February 1856.
PROVISIONAL SPECIFICATION left by the said George Parry at the Office,
of the Commissioners of Patents, with his Petition, on the 26th February.
1856..
I, GEORGE PARRY, of the Ebbw Vale Iron Works, in the County of
Monmouth, Furnace Manager; do hereby declare the nature of the said?
Invention for AN IMPROVEMENT IN THE PUDDLING AND REFINING OF IRON, to'
be as follows:-
This Invention relates to the puddling and refining of iron, the object
being to subject the mass of metal while in a molten state to the action of the
elements of water, and thereby to disengage the sulphur and other volatilizable
impurities therefrom. For this purpose, instead of using steam (as at present)'
which by its comparatively low temperature chills the metal at the points of
injection, and thus produces but a feeble action upon the surrounding or con-
tact surfaces, I propose to superheat the steam prior to injecting it into the
fluid metal, and by thus causing the steam to approach more nearly to the'
temperature of the molten metal to obtain a more efficient chemical action.

page_text: The steam I conduct from any ordinary steam generator to a coil of pipe sub-
jected to the direct heat of a furnace, and in circulating through this pipe it
will take up the amount of caloric required to convert it into what is known
as surcharged or superheated steam, and fit it for the purpose of the present
Invention.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Parry in the Great Seal Patent Office on the
26th August 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
PARRY, of the Ebbw Vale Iron Works, in the County of Monmouth, Furnace
Manager, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of February, in the year of our
Lord One thousand eight hundred and fifty-six, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said George Parry, Her special license that I, the said George Parry, my exc-
cutors, administrators, and assigns, or such others as I, the said George Parry,
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 "AN IMPROVEMENT IN THE PUDDLING AND REFINING OF
IRON," upon the condition (amongst others) that I, the said George Parry, by
an instrument in writing under my hand and seal, 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 George Parry, do hereby declare the
nature of my said Invention, and in what manner the same is to be peformed,
to be particularly described and ascertained in and by the following statement,
reference being had to the Drawings hereunto annexed, and to the letters and
figures marked thereon (that is to say):-
1
My Invention relates to the subjecting of iron while in a molten state to
the action of the elements of water, for the purpose of disengaging the sulphur
and other volatilizable impurities therefrom. For this purpose, instead of using

page_text: steam (as at present) which by its comparatively low temperature chills the
metal at the points of injection, and thus produces but a feeble action upon
the surrounding or contact surfaces, I superheat the steam prior to injecting it
into the fluid metal, and by thus causing the steam to approach more nearly
to the temperature of the molten metal, I obtain a more efficient chemical
action.
In the puddling of iron according to my Invention, I use fixed tuyères for
the injection of the heated steam into the molten iron, such tuyères having
therein orifices above the surface of the molten metal. The tuyères project
through the sides of the puddling furnace, and when they are intended to to
direct jets of heated steam on to the surface of the metal they are inclined at
an angle from the perpendicular. In practice, this angle will be found effec-
tive between thirty and fifty degrees; but I prefer about thirty-five degrees.
The distance of the points of the tuyères or jets above the surface of the
molten iron will vary according to the pressure used; with the ordinary work-
ing pressure from two to four inches of elevation, or thereabouts, will answer
best. The object in elevating the jet above the surface is to give the current
of steam an additional dose of heat before it strikes the iron, by carrying down
and mixing with it the highly heated atmosphere of the furnace, and thereby
further increasing its action on thé molten iron, for the higher the heat the
greater the chemical action. The point of elevation must bear some pro-
portion to the pressure used, or the steam will not reach the surface of the
iron with sufficient force to produce a maximum effect; and this force must
always be equal to depress the surface of the iron, and by reason of the incli-
nation of the jets give it a gyratory motion around the furnace, thus bringing
fresh surfaces of iron continually in contact with the jets of steam. For
white and mottled iron, and bright grey iron, or No. 3, I use two tuyères of
iron tubing three-quarter inch diameter, one each side of the working door of
the furnace; but for a more highly carburetted iron, I recommend a greater
number, in order to obtain the most decisive effect. The points of the tuyères
are preserved from burning by occasionally arming them with a lump of soft
fire-clay, through which a pricking rod is driven by first removing the plug at
the other end of the tuyère, or water tuyères may be used.
In the accompanying Drawings, Fig. 1 represents a side view (partly in
section) of a puddling or reverberatory furnace, fitted with a coil of pipe for
superheating the steam, and an arrangement of pipes for conveying the super-
heated steam to the tuyères; and Fig. 2 is a cross section of the same. A is
the cock for turning on and regulating the supply of steam, which is obtained
from any ordinary steam generator; B is a trap to catch the condensed water';

page_text: C, a coil of pipe, placed in a chamber connected to the furnace chimney by
the flue D, and to the neck of the furnace by the flue E; C, C, the tubing,
for connecting the coil C with the tuyères; F, a damper, for regulating the
heat of the chamber containing the coil of pipe; G, G, the two tuyères,
dipping through the wall of the furnace, and closed at top with a movable
plug.
The mode of operating is as follows:-The iron having been brought to a
fluid state the steam cock is opened, and the puddler proceeds to work the iron
with his rabble, as usual, with this exception, that at the period the metal begins
to thicken by conversion into wrought iron, a greater number of strokes of the
rabble must be given opposite the tuyères than at other points of the furnace.
When the process of boiling has so far progressed that the rabble can no
longer be used, owing to the weight of wrought-iron made, the steam is cut
off, and the "heat" of iron finished in the ordinary manner.
By this mode of working with two tuyères, as described, the time usually
occupied in boiling is reduced by about one-half, while the general character
of the iron is much improved. If, however, a greater improvement in quality,
irrespective of time, be the object in view, the process must be varied. The
puddler, instead of using his rabble with the usual vigour, will leave the iron to
be principally acted upon. by the oxygen of the steam, the other element of
which (hydrogen) in escaping carries off in a gaseous state most of the impu̟-
rities contained in cast iron, and more especially sulphur, phosphorous, and
arsenic; but still the rabble must be used to some extent, in order to keep the
iron free from the cold bottom of the furnace. When sufficient wrought iron
has been made to necessitate its removal by the "paddle," it is placed in the fur-
nace as far as possible from the tuyères, and the remaining fluid cast-iron still
unconverted is brought under the action of the steam, and the converting
process is continued till the whole of the metal has been "dried. up," after
which, during the time of welding or balling, a very gentle blast of steam only
is kept on.
The jets of steam are also found to enhance in a remarkable degree the
effect (upon the iron) of other substances which have hitherto been used in
the puddling furnace, either with a view of increasing the yield or improving
the quality of the iron. I have found that by using rich oxides of iron the
amount of iron drawn is greater than the pig iron charged, a result which I
never obtained before the use of the jets of steam, and also that a greater
improvement in quality has resulted by the use of oxides of manganese or
mixed oxides of manganese and iron, such as spathose ores, than has hitherto
been obtained by simply raking them up with the molten iron, and that the

page_text: greatest effect is produced by adding those substances in about five minutes
after the steam has been turned on.
With bad iron containing little carbon and large quantities of sulphur and
phosphorus, and sometimes a large alloy of silicon, and which does not keep
long boiling, but falls on the bottom of the furnace in a pasty and intractable
mass, I have found very considerable benefit in yield, time, and quality by
subjecting this mass to the action of as strong a current of steam from the
tuyères as it would bear without reducing its temperature too low, the puddler
in the meantime working it in the usual manner.
With superheated steam considerable advantage is gained by steaming the
cinder left in the furnace, with the door partly open, after the heat of iron has
been drawn. When water or cold damp steam is applied it quickly produces
a pasty mass from refrigeration, with little or no chemical change, but with hot
dry steam oxidation goes on rapidly, and the cinder, although kept at a high
temperature, becomes solid and more difficult to fuse. A chemical change will
also be found to have taken place in the combination of the oxide of iron with
the silica by the peroxidation of the former as well as in the expulsion of part
of the usual impurities before named; hence, a beneficial effect on the quality
of the next charge of iron will accrue, as well as a greater stability in the
sides and bottom of the furnace be obtained.
In the refining of pig iron or converting it into what is known as refined
metal, I use a reverberatory furnace, similar to the one described, only larger,
and capable of containing one and a half to two tons of molten iron; but
instead of a cold iron bottom, as in ordinary puddling furnaces, I furnish it
with a fire-stone, fire-clay, or sand bottom. The tuyères are arranged in the
same manner as above, and are nine in number, (viz,) two each side of the
working door, and five at the back of the furnace at nearly equal distances.
The heat of the furnace having been got up, the charge of iron is run in, and
the steam turned on. The refiner soon with his rabble moves the iron in the
vicinity of the tuyéres, and repeats this action occasionally, and, if necessary,
in other parts of the furnace as the operation proceeds. When this has been
sufficiently protracted, which may be known by a little practice, the furnace is
tapped, and the refined iron run into moulds, as at present in use at the ordinary
blast refineries. The "metal" made by this process, from the decarburation
5 of the iron having been mainly effected by the oxygen of steam instead of that
of atmospheric air, together with its freedom from contact with coke (which
always contains sulphur), will be found to prove of greatly superior quality.
In the puddling and refining of iron, I have hitherto spoken of injecting the
steam on the surface of the molten iron when in shallow depths. In the

page_text: refining of iron, however, the process admits of a variation. For this purpose
the walls of the reverberatory furnace are made stronger than usual, leaving
an oblong trough for the reception of the metal, two and a half feet wide, tw
feet deep, and four feet long, or thereabouts, being a convenient size. The
bridge must also be well protected by passing a strong current of air through
it. The orifice of the tuyères is placed very near to the bottom of the furnace
so that the discharge of highly heated steam may take place deep in the body
of the metal, and bubble up through it. The furnace is furnished with an
extra door on the opposite side for the convenience of renewing the points of
the tuyères, as before described. The depth of fluid iron to be acted upon
should be about eighteen inches, or more, as a lesser column of metal will not
be found so effective. After the heat of the furnace has been got up the steam
is turned on a few minutes previous to the charge being run in, in order to
insure the perfect dryness of the steam previous to its contact with the fluid iron.
The pressure of the jets of steam must, of course, exceed that of the column
of metal acted upon, and the absolute quantity of steam passed through cach
tuyère in a given time must bear some relation to the height of the column of
metal to be acted upon, it being so regulated that as little as possible of spare
oxygen shall escape at the surface; any excess above this would tend to
reduce the temperature of the mass of refined iron, and impair its fluidity.
The iron having been sufficiently decarbonized is run into moulds as usual.
In the refining, by my improved process, of iron for subsequent conversion
into steel, I use a reverberatory furnace capable of raising a very high tempe-
rature of the size of an ordinary puddling furnace, but supplied with a warm
fire stone, or sand bottom. With this furnace I use four steam tuyères, viz.
one on each side of the door, and the other two at the back of the furnace.
I charge the furnace with about four hundredweight of highly carburetted pig
iron, and when melted the steam is turned on, and allowed to act on the iron
with the least possible use of the rabble. When the ebullition has proceeded
to a sufficient extent, the furnace is tapped, and the metal run into water to
granulate and partially oxidize it. This granulated iron, on refusion in cruci-
bles with an admixture of the ordinary purifying agents now in use, will be
found to produce a good cast steel. If a superior article be desired, in about
five minutes after the steam has been turned on about two per cent. of pipe
clay, or any clay rich in aluminium, in coarse powder, is thrown into the fur-
nace, and soon afterwards from ten to fifteen per cent. (according to the degree
of carburation of the iron used) of calcined spathose, iron ore, or sparry car-
bonate of iron, also in coarse powder, is added. By the action of the jets of
steam the union of a portion of the metallic bases of these minerals with the

page_text: iron is much facilitated, and a better description of refined iron obtained. It
is important that if the white or crystallized spathic ore should be the kind
used, it should be calcined in an oven at a very low red heat; if a high heat
be employed, its power is much impaired for this purpose.
I would here remark, that although I have pointed out but one mode of
heating the steam, I do not intend to confine myself to that mode; and I
consider that the mixing of ordinary steam with highly heated atmospheric
air or other gaseous body, so as to superheat it prior to its contact with the
fluid.iron under the process of puddling or refining, would be an infringement
of my Invention.
Having now explained the nature and object of my Invention of "an
improvement in the puddling and refining of iron," and described the
manner of carrying the same into effect, I wish it to be understood that under
the above in part recited Letters Patent, I claim the employment in the
puddling and refining of iron of superheated steam injected into the molten
metal, in the manner and for the purpose above set forth.
In witness whereof, I, the said George Parry, have hereunto set my hand
and seal, the Twenty-third day of August, in the year of our Lord One
thousand eight hundred and fifty-six.