IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN THE APPARATUS EMPLOYED PROVISIONAL SPECIFICATION
Year: 1866

page_text: LETTERS PATENT to George Henry Benson, of Staleybridge, in the
County of Chester, Engineer, and William George Valentin, of the Royal
College of Chemistry, Chemist, for the Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF IRON AND STEEL, AND IN THE APPARATUS EMPLOYED
PROVISIONAL SPECIFICATION left by the said George Henry Benson
and William George Valentin at the Office of the Commissioners of
Patents, with their Petition, on the 9th October 1866.
I, GEORGE HENRY, BENSON, of Staleybridge, in the County of Chester,
Engineer, and WILLIAM GEORGE VALENTIN, of the Royal College of Chemistry,
Chemist, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN THE APPARATUS EMPLOYED
THEREIN," to be as follows:-
Our Invention consists in an improved method of applying gaseous fuel to
the puddling of iron; we prefer to employ somewhat more capacious puddling
furnaces than those now in general use, and we admit the gaseous fuel and
blast by a tuyere or system of tuyeres so arranged as to cause the flame to.
play over the metal, and also to force the properly mixed gases and blast

page_text: through the molten metal itself. The upper tuyere or row or system of tuyeres
we prefer to use as nearly as possible constantly with a neutral or non-
oxidizing flame; the lower, however, we prefer to use for gases mixed with an
amount of air or blast insufficient to completely combine with and consume
the combustible gases. The unburnt hydrogen and hydrocarbon gases, as
well as the steam produced by the combustion of hydrogen and hydrocarbon
gases, will exercise a reducing and purifying action upon the metal; or the
gases may be mixed during the "boiling-up." stage of the puddling operation
with an excess of air, and so produce a powerfully oxidizing or decarbonizing
action upon the metal.
In carrying out our Invention we employ a puddling furnace of a somewhat
altered construction from that now used by adapting our concentric tuyere or
system of concentric tuyeres on the side of the present fire-bridge wall so as
to cause the flame to completely fill the furnace and to impinge upon the
metal. A tuyere or series or system of tuyeres are also placed at a lower
level, and the flame therefrom made to act upon tlie metal in the molten state.
The concentric tuyere or tuyeres are placed some little distance back so as to
discharge their gaseous mixture first into a small chamber running in a wedge-
shaped form across the whole width of the anterior part of the puddling
furnace, and opening by means of a broad but low slit or some other appro-
priate outlets into the furnace; this mixing chamber is made of fire-proof
material. The nozzles of the tuyeres are made oval shaped or flattened so as
to leave as little space as possible between the different sheets of flame issuing
from the several tuyeres. The wedge-shaped combustion chamber is inclined
slightly downward, so as to cause the broad sheet of flame somewhat to impinge
upon the cinder bath and upon the metal itself in the furnace. The gases
and blast are sent in through the upper tuyere or row of concentric tuyeres
under slight pressure. A second tuyere or lower row of tuyeres delivers its
gaseous fuel under a gentle pressure sufficient to overcome the resistance of
the molten metal through which it has to force its way. The delivery through
the tuyeré or tuyeres of the gases and blast under pressure is accomplished
by means of a fan blåst for the hot gases, and an ordinary blast engine
or fan for the atmospheric air. The blast is heated by means of the waste
heat that passes off from the puddling furnace. The gaseous fuel-as it issues
from the nozzles of the lower tuyere or series of concentric tuyeres is made
to pass into a short wedge-shaped mixing chamber, from which it is forced
through a series of holes made in the plate or wall, or a series of tuyeres
made of fire-proof material, which close the narrow slit of the lower, mixing
chamber. We prefer to force the gaseous mixture into and through, the

page_text: metal in the form of a number of fine streamlets, because during the boiling.
up of the metal in the cinder bath it will be found highly advantageous to use
an oxidizing or decarbonizing flame; and thus to assist the decarbonizing action
of the cinder bath, and to materially accelerate the "boiling.up." The work
of the puddler will be greatly facilitated, and the metal will be brought to
"nature" in a much shorter time. Previous to this we prefer to keep this
lower flame as much reducing as possible, and as rich in bydrogen and other.
reducing gases capable of acting upon sulphur and phosphorus as possible..
The "balling" of the iron will likewise be greatly facilitated by the ease with
which the admission of the gaseous fuel into the puddling chamber and the
nature of the flame can be regulated. If it be desired to make a kind of
puddled steel we can regulate the oxidizing flame that issues from the lower.
tuyere or row of tuyeres and the amount of oxide of iron in the cinder bath,
so as to enable the puddler to produce puddled steel of any desired quality.
The pressure upon the gaseous fluids is regulated by means of self-acting
valves and throttle valves in the conveying pipes.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Henry Benson and William George Valentin in the
Great Seal Patent Office on the 9th April 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, GEORGE.
HENRY BENSON, of Staleybridge, in the County of Chester, Engineer, and
WILLIAM GEORGE VALENTIN, of the Royal College of Chemistry, Chemist, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of October, in the year of our Lord
One thousand eight. hundred and sixty-six, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said George Henry Benson and William George Valentin, Her special
licence that we, the said George Henry Benson and William George Valentin,
our executors, administrators, and assigns,, or such others, as we, the said
George Henry Benson and William, George. Valentin, our executors, ad
ministrators, 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 MANUFACTURE OF IRON AND STEEL,

page_text: "
upon
AND IN THE APPARATUS EMPLOYED THEREIN,
the condition (amongst
others) that we, the said George Henry Benson and William George
Valentin, our executors or administrators, by an instrument in writing under
our, or their, or one of our or their hands and seals, should particu-
larly 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 we, the said George Henry Benson and William
George Valentin, do hereby declare the nature of our 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 annexed, and to the letters and figures marked thereon
(that is to say):-
Our Invention of "Improvements in the Manufacture of Iron and Steel
and in the Apparatus employed therein," relates to an improved method of
applying gaseous fuel and atmospheric blast to the puddling of iron.
In carrying out our improvements we prefer to employ somewhat more
capacious puddling furnaces than those now in general use, and we admit
the gaseous fuel and blast to the puddling furnace by means of a system of
tuyeres so arranged as to cause the flame to play over and through the metal.
The objects we have in view aře, first, so to control the supply and action
of the gases and blast as to produce a flame of such a nature as to melt
down the iron in the cinder bath as rapidly as possible; also to eliminate
from the iron during the boiling-up stage the silicon and the proper proportion
of carbon, and to purify it to some extent from certain impurities, such
as sulphur and phosphorus; this is effected by the agency of gaseous
bodies, such, as hydrogen and hydrocarbons contained in the flame, as well as
steam, which is a product of combustion; and, lastly, during the balling
operation to keep the puddled balls hot without changing the character of
the iron or puddled steel. For this purpose we prefer to deliver the gaseous
fuel into the puddling furnace through a concentric tuyere or tuyeres or system
of tuyeres set in one or two rows or tiers in the walled-up or anterior end of
the furnace, from which in ordinary puddling furnaces the flame enters over
a fire-bridge, and we are enabled by this arrangement to mix and control
the quantity of atmospheric blast and combustible gases which are required
to produce the different heating effects essential to conduct the puddling
process or the conversion of crude iron into malleable iron or into puddled
steel to the best advantage.

page_text: In the accompanying Drawing, Fig. 1 represents a longitudinal vertical
section, and. Fig. 2 a sectional plan view of a puddling furnace constructed
and arranged with a view to effect these objects.
a, a, is the puddling furnace, and 6 and 6 the two rows of tuyeres which
we prefer to use for the admission of the combustible gases and atmospheric
blast. Both sets of tuyeres are placed some little distance back so as to
discharge their gaseous mixture, first, into a small chamber or series of
chambers c, c, constructed of fire-proof material, and running in a wedge-
shaped form across the whole width of the anterior part of the puddling
furnace. The upper chamber c opens by means of a wide but low slit into
the furnace, while the lower chamber or set of chambers discharge the flame
through a series of perforated fire-clay nozzles or perforated bricks in fine
streamlets through the metal bath into the furnace. The nozzles of the
tuyeres are made oval-shaped or flattened so as to leave as little space as
possible between the different sheets of flame that issue from the several
tuyeres, and both tuyeres and mixing chambers are inclined at an angle
sufficient to cause the broad sheet of flame from the upper row of tuyeres to
play down and to impinge upon the metal. The flame from the upper row of
tuyeres issues under a gentle pressure so as to fill the whole furnace and to.
spend itself as much as possible in the large puddling chamber. The second
or lower row of tuyeres discharges its products of combustion together with
more or less of combustible gases or atmospheric blast in fine streamlets into
the metal bath under a pressure sufficient to overcome the resistance of the
molten metal; this we effect by generating.combustible gases in a close
apparatus or gas generator with the aid of a fan blast or ordinary blast engine
capable of producing blast of sufficient pressure to pass through the ignited
fuel in the closed gas generator, and thereby to convert the carbonaceous fuel
into combustible gases, consisting principally of carbonic oxide, hydrogen, and
hydrocarbon gases, and by conveying such combustible gases through suitable
conduits to the concentric tuyeres when they become mixed with the proper
amounts of atmospheric air so as to cause complete combustion and to
discharge the products of combustion which possess an intense temperature
into the furnace under the required pressure. The different pressures at
which we discharge the products of such combustion we regulate and control
by means of throttle valves or other suitable contrivances, such as are well
understood. The amount of atmospheric blast which has to be mixed with
the combustible gases must depend upon the chemical constitution of the
gases, and varies with the kinds of fuel employed in the gas generators, but
admits of ready calculation. The temperature of the gases and blast to be

page_text: mixed, and the pressure at which the mixture should be discharged, must
likewise be taken into account according to well understood laws. In order
to utilize the waste heat and to produce as great a heating effect as possible
from the combustion of the gases generated in the gas generator we heat
the atmospheric blast, and we mix the gases in the tuyeres and mixing.
chambers previous to their issue into the puddling chamber by preference
only with hot atmospheric blast (likewise under the proper pressure). For
the purpose of heating the blast on its passage to the tuyeres we employ a
heating stove of the ordinary description, through which we cause the highly-
heated products of combustion to circulate prior to their being discharged into
the chimney stack. Although we prefer to employ concentric tuyeres of the
above description for mixing the gases and blast we wish it to be understood
that we do not make any claim to their exclusive use, as the process of
mixing combustible gases with atmospheric blast safely admits of considerable
variation ; we do not, therefore, intend to confine ourselves to the plan shewn,
provided an intimate intermixture of gases and hot blast under pressure and
thorough combustion can be attained.
We conduct the puddling operation in the following manner :-
:-During the
time when the crude or pig iron is melting down in the cinder bath we
employ from both series of tuyeres a flame containing slight excess of com-
bustible gases.
It is known that the highly heated steam contained among
the products of combustion, as well as the excess of bighly heated unburnt
bydrogen and hydrocarbon gases, exert a beneficial purifying effect by acting
upon sulphur and phosphorus. When the iron is melted down and well
diffused throughout the cinder bath we change the flame from the lower
tuyeres to an oxydizing or decarbonizing flame by allowing excess of atmos-
pheric blast to mix with the combustible gases discharged from the tuyeres,
so as to accelerate the "boiling-up" of the metal and its coming to "nature;"
the steam will be found to act equally beneficially at this stage of the process.
When the bath begins to thicken, and the iron is ready for balling, we change
the flame from both lower and upper tuyeres to a reducing flame, so as to
,prevent the useless oxidation of the metal; the puddler is thus enabled by the
exercise of proper control over his cinder bath to produce puddled iron or
puddled steel of any desired quality, and the work of puddling or bringing the
iron thoroughly into contact with the exide of iron in the cinder bath will be
materially assisted and facilitated, and the whole process of puddling brought
more under control than hitherto.
Having now described our Invention of "Improvements in the Manu-
facture of Iron and Steel, and in the Apparatus employed therein," and

page_text: having explained the manner of carrying the same into effect, we claim as the
Invention secured to us by Letters Patent as aforesaid,―
First, the mode herein set forth of operating upon iron in the puddling
furnace by means of gaseous fuel, whereby the puddling operation is brought
under control and materially assisted by the flame from the lower tuyeres, and
whereby we are also enabled if desired to produce puddled steel of a more
certain and definite character and quality than heretofore.
Second, we claim the arrangement and construction of apparatus herein
shewn and described for operating upon-iron in the puddling furnace by-
means of gaseous fuel.
In witness whereof, we, the said George Henry Benson and William
George Valentin, have hereunto set our hands and seals, the Twenty-
eighth day of Marcb, in the year of our Lord One thousand eight
hundred and sixty-seven.
G. HENRY BENSON.
(L.S.)
W. GEO. VALENTIN. (L.s.)
G. HENRY BENSON.
(L.S.)
W. GEO. VALENTIN. (L.s.)