IMPROVEMENTS IN PUDDLING IRON
Year: 1869

page_text: LETTERS PATENT to Henry Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer,
for the Invention of "IMPROVEMENTS IN PUDDLING IRON."-A com-
munication from abroad by Charles Hewitt, of Trenton, in the
State of New Jersey. United States of America.
PROVISIONAL SPECIFICATION left by the said Henry Edward Newton
at the Office of the Commissioners of Patents, with his Petition,
on the 23rd April 1869.
I, HENRY EDWARD NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Civil Engineer, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN PUDDLING IRON," to be
as follows:-
The object of this Invention is to produce iron of a better quality than
other puddling processes will yield and with a less expenditure of fuel,
labour, time, and wear and tear of tools and apparatus. The process

page_text: consists in mixing cast iron divided into coarse granules or pieces varying
from one-fifth of an inch to an inch in bulk with oxide of iron, then
melting, stirring, and boiling them together. The process is then
completed by balling the iron thus obtained in a puddling furnace.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Edward Newton in the Great Seal Patent
Office on the 22nd October 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of April, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Henry Edward Newton, Her special
licence that I, the said Henry Edward Newton, my exccutors, adminis-
trators, and assigns, or such others as I, the said Henry Edward
Newton, 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 exprscsed, 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 Inven-
tion for "IMPROVEMENTS IN PUDDLING IRON," being a communication to
me from abroad by Charles Hewitt, of Trenton, in the State of
New Jersey, United States of America, upon the condition (amongst
others) that I, the said Henry Edward Newton, 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.

page_text: NOW KNOW YE, that I, the said Henry Edward Newton, 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 (that is to say) :-
The object of the present Invention is to produce iron of a better
quality than other puddling processes will yield and with a less
expenditure of fuel, labor, time, and wear and tear of tools and apparatus.
In the ordinary process of puddling the cast iron to be puddled is
charged into the puddling furnace in the form of pigs with about thirty
per cent. of its weight of forge cinder, and sometimes with the addition
of about five per cent. of its weight of rich oxide of iron ore. The ore
or cinder, as the case may be, is for the purpose of aiding in decarbonizing
the pig iron and combining with and separating from the iron the sulphur
and other foreign matters (injurious to the quality of the wrought iron)
which it is the object of the pudding process to produce from the cast iron.
In the ordinary puddling process the iron oxide is not mingled with the
mass of the pig iron and brought into intimate contact with it until the
latter has been under the action of an oxidising flame long enough to
become to a considerable extent decarbonized and heated sufficiently to
become friable, at which time the pigs are broken down and disintegrated
by means of stirring bars operated by workmen, the disintegrated iron
falling into the oxide which lies melted on the bottom of the hearth and
is fusible at a much lower temperature than cast iron. As the heat
continues the iron will soon attain a temperature sufficient to cause it to
boil in the oxide bath, and by this means and stirring with a bar every
part of the mass of the iron is brought into intimate contact with the
oxide during the latter stages of the puddling process. The importance
of bringing the cast iron into intimate contact with the iron oxide in the
early as well as the later stages of the puddling process has been
recognized and various plans have been devised for the accomplishment
of this object. Among other things it has been proposed to reduce the
cast iron to a state of fine division, then mix it with the required
proportion of iron oxide also in a state of fine division, and then to heat
the mixture in an adjunct to the puddling furnace until the cast iron is
so far decarbonized as to become infusible under the ordinary heat of the
furnace, when it is to be transferred to the hearth of the puddling
furnace and stirred and balled up without melting in the ordinary way.

page_text: Such a process is described in Willian's English Patent No. 702, dated
Eighth March One thousand eight hundred and sixty-six. Cast-iron
turnings, borings, and chips have also been mixed with finely divided
oxide and forge cinder and then puddled, but the cast iron being in such a
state of fine division was in such cases decarbonized and rendered infusible
without being first melted. These processes and all others heretofore
proposed for puddling cast iron in a state of fine division mixed with
iron oxide also in a state of fine division would, if practically successful,
have expedited the process and so saved fuel, labor, and wear and tear, &c.
of tools and apparatus, but they have failed to produce wrought iron of as
good a quality as the same materials would yield by the ordinary process
of puddling cast iron obtained from pigs, and therefore these processes
have never superseded the common process; this inferiority of the
product is caused by the conversion of the cast iron into wrought iron
without being melted and mingled in a fluid state with the melted and
fluid iron oxide. When cast iron in the state of a thin fluid is mingled
intimately with fluid iron oxide the latter induces the separation from
the iron of sulphur, phosphorus, and other matter whose presence would
impair the strength, flexibility, or tenacity of wrought iron made from
it, but if the process of decarbonization of the cast iron has taken place
to even a small extent before melting its fluidity is thereby lessened, and
if the decarbonization has gone to a considerable extent the melted iron
will only be a thick and almost pasty mass incapable of being intimately
mixed with fluid oxide in the puddling furnace so as to expose fully or
efficiently the sulphur, phosphorus, and other impurities which it
contains, and permit them to be absorbed, washed out, or otherwise
withdrawn by the fluid oxide. It is therefore important to prevent
as far as possible decarbonization of the cast iron previous to its being
melted and mixed with the fluid iron oxide.
It is one object of this Invention to retain all the advantages of the
common process of puddling cast iron from pigs and all the advantages
gained in the processes of puddling cast iron in the form of fine granules,
pieces, or turnings mixed with finely divided iron oxide, and at the
same time to eliminate the defects of these former puddling processes.
Another object of the Invention is the production of a better quality
of wrought iron from given materials than can be produced by any
puddling process before known. The improved process consists in

page_text: reducing the cast iron to coarse granules or pieces so that they may
melt down more quickly than pigs into a fluid state. Granules or
pieces varying in bulk from spheres of about two-tenths of an inch
to one inch in diameter with a small portion larger and smaller than
these limits have been found in practice to work satisfactorily. Care
must be taken, however, not to make too large a proportion of fine
granules, as in that case they would quickly be decarbonized and
rendered infusible and thus prevented from melting and mixing in a
liquid condition with the liquid iron oxide. Such a mixture of the iron
(in a liquid state) with the liquid oxide is indispensable to the complete
success of the process. It is important also that the granules or pieces
of cast iron should not be too large, because in that case they would
have to be so long exposed to the heat to produce fusion that the iron
would become partially decarbonized, its fluidity when melted lessened,
and in a corresponding degree lessening its penetrability by the fluid
iron oxide, which washes out or induces the separation of the sulphur,
phosphorus, or other impurities from the iron when both the oxide and
iron are interpenetrated or are intermixed thoroughly while in a high
state of fluidity. In this improved process a rich oxide of iron ore
divided into granules or pieces about the same size as the iron granules
is mixed with the cast iron to decarbonize it. Different kinds of cast
iron and different kinds of ore will have to be mixed in different
proportions. In the use of common anthracite gray iron its decar-
bonization could be thoroughly effected by twelve and a half per cent..
of its weight of magnetic oxide of iron ore containing about sixty-five
per cent. of metallic iron. The granulated iron and ore in the proper
proportions is mixed thoroughly and evenly, and the mixture is charged
into the puddling furnace in the same quantity that would be used for
an ordinary charge of pig iron; the heat is now let on, and tho changes
are so rapid that within two or three minutes the stirring of the mixture
must be begun in order to raise the cooler granules from the bottom
and allow the hot upper granules to descend, thus hastening the melting
down and keeping the iron and oxide thoroughly intermixed; in the
course of fifteen minutes the iron and orc will be completely fused
(both in a highly fluid state) and intimately intermixed; the boiling
next begins and the stirring of the boiling mass is continued; in
about eleven minutes the oxide or cinder will drop from the iron,
leaving the latter in spongy pasty lumps, which require turning over

page_text: frequently for about ten minutes to complete the decarbonization. The
iron is now in a state of greater purity for being formed into puddled
balls, and withdrawn from the furnace. This process occupies much
less time than the ordinary process of puddling pigs, consequently it
saves fuel and labor, which are both expended in proportion to the
time occupied in going through with the process; it lessens the wear of
the furnace, which is in some degree proportioned to the continuance
of the heat; it also saves capital by giving to the same puddling furnace
a greater capacity in proportion as the time required for operating on
a charge is shortened; it saves waste, as the loss from oxidation of the
iron is in some measure proportioned to the duration of the operation;
it lessens the risk of losses from inattention by lessening the stretch of
attention required on the part of the workman; and with all these
advantages in the operation of this process the product is a wrought
iron of greater purity and higher value than has heretofore been yielded
by puddling.
It is unnecessary to describe the puddling furnace or the manner of
operating it, as the ordinary furnace in general use in the trade is
employed, and is well known to all who are skilled in the manufacture
of wrought iron. For a similar reason it will not be necessary to
describe the manner in which ore may be reduced into small pieces
by means of rolls, stamps, hammers, and screens, nor the manner in
which cast iron may be reduced into small pieces by running it while in
a molten state upon a rotating centrifugal scatterer and thence into
water, or dropping it directly into water, or casting it in rods or thin
plates with breaking creases, and then breaking it up by stamping or
otherwise, as all such methods of dividing or granulating metals and
other materials are well known in the trade. The operation of reduc-
ing the material to a suitable state of division is greatly simplified by
dispensing with the smallness and uniformity in size of granules, which
is almost if not quite indispensable in the methods previously proposed
for using them in the puddling furnace.
Having now described the Invention which has been communicated
to me by my foreign correspondent, and having explained the manner
of carrying the same into effect, I claim as the Invention secured to
me by Letters Patent as aforesaid, mixing cast iron divided into coarse
granules or pieces with granulated oxide of iron, and then melting,

page_text: stirring, boiling, and puddling the same together in a puddling furnace,
and then balling up the wrought iron thus obtained, as herein* set
forth.
In witness whereof, I, the said Henry Edward Newton, have
hereunto set my hand and scal, the Nineteenth day of October,
in the year of our Lord One thousand cight hundred and sixty-
nine.