IMPROVEMENTS IN THE PROCESS OF AND APPARATUS FOR PRODUCING WROUGHT I
Year: 1883

page_text: LETTERS PATENT to Edwin Powley Alexander of 36 Southampton Buildings
in the County of Middlesex Fellow of the Institute of Patent Agents for an
Invention of "IMPROVEMENTS IN THE PROCESS OF AND APPARATUS FOR
PRODUCING WROUGHT IRON a communication to him from abroad by
Lucius Delison Chapin of Chicago, Illinois in the United States of America;
Gentleman
"
COMPLETE SPECIFICATION filed by the said Edwin Powley Alexander at
the Office of the Commissioners of Patents on the 17th August 1883.
EDWIN POWLEY ALEXANDER of 36 Southampton Buildings in the County of
Middlesex, Fellow of the Institute of Patent Agents. ** IMPROVEMENTS IN TUE
PROCESS OF AND APPARATUS FOR PRODUCING WROUGHT IRON " a communication,
to me from abroad by Lucius Delison Chapin of Chicago Illinois in the United
States of America Gentleman,
This invention consists first in an improved method or process of making wrought
iron and secondly in improved apparatus that may be used among other purposes
for carrying such process into effect.
In the manufacture of wrought iron as ordinarily practised the charge of cast
iron is subjected to the reducing action of the furnace gases on a reverberatory
hearth having a fix or fettle made up in considerable measure of iron oxide, either
in the form of ore or of mill cinder scale or the like. The presence of the oxide
lining is deemed highly essential to the successful working of the charge for
without it when the metal comes to "nature"" and is in pasty condition ready to be'
collected into a ball or loop the wrought iron adheres tenaciously to the silicious
lining thus making it extremely difficult to work into a mass and then only at
a great loss of the metal. Hence it is that to avoid the difficulty precaution is taken
to supplement the usual lining with charges of iron oxide in various forms and
combinations spread upon the hearth above the same and next in contact with the
molten metal. Practice has demonstrated that in this way the cast may be reduced
to wrought iron with entire economy save that after each heat or at best after very
few heats it is necessary to renew the iron oxide lining which not only consumes

page_text: time in bringing the furnace again into "condition” but is wasteful moreover of
crude materials rich in iron.
The first part of the present invention has for its object to avoid the repeated
and neccessarily expensive renewal of the oxide lining in manufacture of wrought
iron and is based upon the discovery that if the crude cast iron be subjected to a
preliminary treatment in a pneumatic converter having the usual lining of fire-
brick ganister or like silicious material until said cast iron is practically free from
silicon and a large percentage of its carbon the iron may then be transferred to a
reverberatory hearth having an iron oxide lining and therein speedily reduced to a
wrought condition without material loss of oxide lining and consequently without
the frequent renewal of said lining which the methods of manufacture heretofore
in vogue have made neccessary.
In the specification to Letters Patent heretofore granted and numbered 739 of
A.D. 1880 is described and claimed a process or method of making wrought iron
wherein the molten metal while enclosed in a converter was subjected simul-
taneously to the oscillatory or rotary action of the converter and to the action of an
air blast until it approachod "nature" with an occassional intermitting or varying
of one action or the other as therein described if so required after which the metal
was transferred to a separate furnace or balling chamber and balled under a
reverberatory heat or flame. The form of converter shown in said specification
and described as preferable is somewhat of the type or kind known as the "Danks"
furnace and with such a converter was contemplated the use of a lining somewhat
like the one commonly used in the "Danks "furnace and which in its characteristic
features resembles the lining fix or fettling usually employed in puddling or boiling
furnaces.
Such linings have usually a considerable percentage of oxide of of iron or other
metallic elements which are supposed to "nourish" the iron under treatment and
to facilitate its coming to "nature." It was with reference to the use of linings of
that general. class that there was described the oscillatory or rotary motion of tho
converter more or less intermittently as an element of the invention set forth in
said specification
"
If instead of said non-refractory linings having a considerable percentage of iron
oxide or other metallic elements in their composition the lining of the converter be
of fire-brick ganister or like silicious material it will be found first, that it is
unneccessary to impart to the converter any oscillatory or rotary motion during the
first stage of the process; second, that in subjecting the molten metal to the action
of the air blast alone for a few minutes until it more or less approaches "nature
or comes to a degree of conversion corresponding thereto the refractory lining is
attacked but slightly and indeed very much less than when a non-refractory lining
is employed as specified thus saving the expense of frequent renewal whilst third,
the iron is left in such purified condition that upon subsequent transfer to a baller
having a metallic lining usual to a puddling balling or "Danks" furnace it can be
speedily reduced therein to a wrought condition under influence of a reverberatory
flame with practically little or none of the disastrous "cutting" of the lining
which has been heretofore experienced.
In the practice of the first part of the present invention the apparatus herein-
after described as constituting the second part of this invention is preferably
employed. For this purpose the converter is to be lined with ganister fire-clay or
other suitable refractory material especially excluding any such percentage of
metallic oxides as is usually employed in the Danks or in ordinary puddling or
boiling furnaces. The charge of metal may be run in from the cupola or blast
furnace and then treated with the air blast substantially as described in said
specification (No 739 of A. D. 1880) except that the converter need not be rotated
or oscillated during the blowing of the blast nor need the metal have any other
motion imparted to it than what results from the blowing of the blast. The blast
is kept blowing for a short time say for ten minutes more or less either until the
metal approaches nature or comes to or approaches a corresponding degree or
st
"

page_text: stage of purification or it may be arrested sooner say after five minutes blowing
through in the latter case the subsequent operations in the baller or balling furnace
will require more time. But in any case the metal should be kept under the air
blast treatment in the converter until the objectionable impuritics which the air
blast is adapted to remove shall have been substantially eliminated or so far eliminated
that the presence of the residue will not in subsequent working prevent the pro-
duction of good iron. The metal is next tapped, run into a transferring ladle or
otherwise transferred to the baller or balling chamber or chambers (one or more)
having any lining such as is adapted to nourish the iron or aid in fluxing or
decarbonizing or otherwise completing its conversion and bringing it completely
to "nature" and such baller or balling chamber may be of any construction and
operation provided only it be such as to admit of the use of a reverberatory heat or
flame on the iron under treatment therein and also permit the use of motion
imparted mechanically to the iron preferably by the rotary or oscillatory motion of
the baller or balling chamber itself. The mechanical work of balling the iron under
such conditions and of removing the ball and further working it is so well known
in the art that further description is unnecessary. In practice of the process as
above described it is found that the quality of the iron is materially improved;
that the labour and expense of its production is much lessened by doing away with
the constant repairs to the converter lining made necessary when this was of
non-refractory materials and that by the subsequent transfer of the metal to the
baller after the first part of the process of conversion carried on in the converter
has been finished the lining of the baller is slightly if at all impaired or if
'impaired is replenished as much or nearly as much as it is worn away and thus
becomes practically self sustaining. This is a great economy as compared with any
process with which I am familiar. Tho whole expense or nearly so of "fix" or
fettling" is avoided in the baller when once lined while the refractory lining of
the converter is very permanent as compared with the lining of an ordinary
puddling or boiling or "Danks" furnace.
E
When crude or cast iron containing phosphorous in injurious quantity is to bo
used for the manufacture of wrought iron the course of treatment above set out is
followed with this addition that I place in the bottom of the transferring ladle and
of the balling chamber a quantity of dolomite which will unite with the phos-
phorous of the iron and form a slag that may be readily removed in any convenient
manner known to the art. The entire charge of dolomite may be placed in the
ladle or in the balling chamber but the preferred mode of treatment is to divide
this charge and place a portion in each. In crude metal containing say from .3 to .5
of one per cent of phosphorous the quantity of dolomite employed may be about
4 to 5 per cont of the entire charge that is to say 95 to 96 per cent of crude iron
and five to four per cent of dolomite but obviously these proportions may be varied
and when the metal is higher or lower in phosphorous the quantity of dolomito
may be correspondingly increased or diminished The dolomite used may be either
raw or calcined but I prefer that the quantity used in the ladle should be raw
whilst that used in the baller shall be calcined.
The apparatus which constitutes the Second part of this invention is illustrated
in the accompanying drawings in which figure 1 is a plan view; figure 2 a view
in transverse section a portion of one of the ballers being broken away for better
illustration and the converter being shown in side elevation; figure 3 is a view
from the front or charging side of the apparatus and figures 4, 5 and 6 are detail
views showing the manner of sustaining the doors of the ballers.
The converting vessel A sustained by trunnions between suitable standards A¹
is of the ordinary pattern used in the Bessemer or pneumatic process for the con-
version of cast iron. Near the front of said vessel A is arranged an elevated
railway B supported by posts or standards B' above the floor of the mill upon
which railway B there runs a wheeled truck frame C' that carries the ladle C.
The ladle C is sustained upon trunnions within the truck frame or carrier C' in a
manner convenient to allow for its being tipped and said ladle as it travels upon

page_text: the railway B' is so arranged with respect to the converter A as that when this
latter is turned upon its trunnions by any of the usual means the mouth of said
converter will stand above the ladle C and the contents of the converter be in part
discharged into said ladle as the operator desires.
Arranged side by side in any number suitable to the capacity of the converter A
is a series of rotary balling furnaces which with the converter and other usual
adjuncts constitute the plant.
The balling furnaces are in the main constructed in manner well known to the
art that is to say having a fuel or fire chamber D fitted with grate-bars a rotary
balling vessel E open at its ends and sustained upon the rollers e e in close juxta-
position to the bridge wall of the fire-chamber I said balling vessel E being free
to revolve through the medium of circumferential rack e¹ affixed thereto, pinion e²
shaft E mitre gear e³ and line shaft E³ the friction clutch gear e upon the shaft E
controlling the period and degree of rotation. These several details of structure
need not be more minutely described because the same are made and coöperate in
the usual well known way..
8
At the front of the balling vessel E there is provided a moveable door F which
may be hinged in any suitable manner so as to swing freely to and from the
mouth of the vessel E. A convenient way is to hinge the door- piece F to a
standard S which with its brace s is firmly retained by bolts to the bed plate S²;
suitable slots in said bed-plate allowing for adjustment of the standard within
certain limits to and fro and laterally and in consequence for adjustment of door F
sustained thereby-so as to compensate for any wear of the parts and to secure a
tight joint between the faces of the door and of the baller E.
The door F consists of a stout.metal.frame.having an opening. -through-it corre-
sponding to that of the baller E and bears upon its outer face a short projecting
flue F of same internal diameter as the opening in door F the parts being properly
lined to prevent the destructive action of the highly heated furnace gases. When
the door F is tightly in position against the mouth of the baller E so that the face-
plate secured to said door bears against the like plate e³ of the baller E then will
the end of the projecting flue pieco F be in position to abut against the corre-
sponding end of the moveable flue G. The flue G may consist of a stout sheet
metal casing lined internally with fire-brick or similar resistant and in the form
shown by the drawings is bent elbow-like the downtake of said flue discharging
freely into a main-flue H common to all of the several balling furnaces which
connects in turn with the ordinary chimney stack. Attached to the downtake of
the flue G is an encircling collar 9 having a circumferential groove in the face
thereof to receive a series of rollers balls or equivalent friction devices which rest
below in a like groove formed in the face of a plate g₁ sustained upon the main
flue H. By this construction the moveable fluc section G is free to swing about
its downtake as an axis and thus at will to be tightly joined to the door F having
the projecting flue F' thereon or to be swung clear and away therefrom as may be
necessary in the working of the balling furnace. It will be noted that the flue
piece F terminates in an opening whose plane is oblique to the door F. The
contour of the abutting end of the moveable flue section G is an exact counterpart
of this opening whereby a practically tight joint is secured between the parts so
that all leaks in the flues shall be avoided. The ends of the flue sections are shown
as curved with an equal radius and from a common centre, this being the preferable
construction. A slide valve G₁ located in flue G controls at will the egress of
furnace gases from the balling vessel to the main flue H so that at any desired
stage of treatment of the charge in the balling vessel the flame- may be shut down
and the charge kept quiescent until such time as the loop of another baller has been
disposed of or other conditions necessary to the economic working of the metal
fulfilled.
It must be apparent that by thus connecting the several flues leading from each
of the balling vessels to a single main-flue the charge of metal in each vessel may
be worked with entire independence and yet if the flame from any one be

page_text: temporarily shut down it can be quickly revived to a degree of high intensity
when the valve G' is shifted and the furnace fire is subjected to the extreme draft
of the common flue and stack. When the connection between the swinging fluo
and the furnace door is broken for the purpose of obtaining access to the interior
of the furnace the valve G¹ is closed to prevent the entrance of air into the main
discharge flue for in the absence of the valve it is clear that such ingress of cold
air must tend to reduce the temperature of the main flue and to materially
diminish the draft when the connection is re-established. If more than one
furnace be used the valves in the several flue sections have the further useful
function of preventing an outflow of hot products of combustion from the main
discharge flue into the working room a detrimental result which in the absence of
the valve must occur when, any one of the furnace connections is temporarily broken
as before described. The common flue H may be located below the floor of the
mill as shown or may be overhead and sustained in any preferred way in which
event the swinging flue section G will be suspended from the same so as to abut
against the projection F' of the door F as heretofore described. Nor is it necessary
to the efficiency of this part of the invention that there shall be a common flue
at all inasmuch as the swinging section E and door F co-operato with each other
and with the puddling furnace to which they pertain with equal success whatever
the nature of the conduit into which swinging flue-sections G may discharge,
By having the flue section G and the door F to swing separately from each
other they are rendered less cumbrous, are easier of access, simpler in construction,
independent in movement yet capable of being quickly and tightly joined together.
More room is afforded because of the compact and simple arrangement of the parts,
thus through the medium of the elevated railway and travelling ladle allowing for
the use of a series of puddling furnaces in connection with a single converter or
cupola.
It will be obvious that the several details of construction heretofore described
may be varied without departing from the spirit of the invention.
Although the apparatus herein shown and described is parparticularly [sic] suited
to the practice of the process constituting the first part of this invention it is to be
understood however that such apparatus is not restricted in value to the practice
of such process nor to any special type of furnace but that the peculiar features
of construction which distinguish said invention make it applicable alike to a
variety of processes and furnaces:
Having now described and particularly ascertained the nature of the sail
invention and the manner in which the same is or may be used or carried into
effect I would observe in conclusion that what I consider to be novel and original
and therefore claim is :-
First. The process of making wrought iron hereinbefore described as constituting
the first part of this invention.
Second. The combination with a furnace of a moveable door, a moveable Blue
section sustained independently of said door and a main discharge flue substantially
as described.
Third. The combination with the furnace of a moveable door having a flue pieco
projecting from the back thereof and terminating in an opening the plane of which
is oblique to the door, a moveable flue piece having an end whose contour is the
counterpart of the door flue piece, and a main discharge flue substantially as
described.
Fourth. The combination with a furnace and the main discharge flue of a
noveable flue-section connected by a union-joint to the main discharge flue
whereby the joint between said moveable section and main flue is maintained
constant during rotation of the flue section substantially as described.
Fifth. The combination with the balling vessel and the main discharge flue of
the moveable flue section connected to the main flue by a joint as described and
provided with a valve substantially as described.
Sixth. The combination with a series of balling vessels and a main discharge

page_text: flue of a series of moveable flue sections cach provided with a valve substantially
as described.
Seventh. The combination with rotary balling vessel E of the hinged door F
the swinging flue section G provided with the collar gand the main flue H bearing
the plate g substantially as described.
Eighth. The combination with the rotary balling vessel of a swinging door and
adjusting mechanism for sustaining said door substantially as set forth.
In Witness whereof I the said Edwin Powley Alexander have hereunto set my
hand and seal this seventeenth day of August in the year of our Lord one thousand
eight hundred and eighty three.
EDWIN Y. ALEXANDER (L.S.)