Improvements in the Manufacture of Wrought Iron.
Year: 1892

page_text: Date of Application, 7th June, 1892
Complete Specification Left, 7th Mar., 1893-Accepted, 29th Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Wrought Iron.
I, JAMES LAKIN, of Swan Garden Cottage, Horseley Fields, Wolverhampton
in the County of Stafford, Ironworks Manager, do hereby declare the nature of
this invention to be as follows:-
This invention has for its object to produce wrought iron of good quality from
cast iron swarf and iron oxide or scale, such as the scale from rolling mills and
tube works or other iron scale or rust, at a considerable reduction in cost compared
with the production of wrought iron by puddling in the ordinary manner.
According to this invention, the cast iron swarf and iron oxide or scale are
mixed with coke or coal dust, and the mixture is charged on to the bottom of a
reverberatory furnace, such for instance as a puddling or ball furnace, and after a
few minutes exposure to the heat the upper surface thereof forms into a cake.
This cake is removed, and the surface then exposed cakes over, and so on until the
whole charge has become caked and resembles lumps of coke. The charge is then
balled up and rolled out into a bar or bars; and the bars thus produced are used
as puddled bars and subsequently dealt with for the production of merchant bars,
plates, sheets, or the like.
Dated thin 4th dore of Tune 1940
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Wrought Iron.
I, JAMES LAKIN, of 15 and 16 Willenhall Road (late of Swan Garden Cottage,
Horseley Fields), Wolverhampton in the County of Stafford, Ironworks Manager,
do hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement :-
This invention has for its object to produce wrought iron of good quality from
cast iron swarf and iron oxide or scale, such as the scale from rolling mills and
tube works, or other iron scale or rust, at a considerable reduction in cost compared
with the production of wrought iron by puddling in the ordinary manner.
According to this invention, the cast iron swarf and iron oxide or scale are mixed
with carbon consisting of small particles, and preferably in the form of coke dust,
and the mixture is charged on to the bottom of a reverberatory furnace, such for
instance as a puddling or ball furnace. After a few minutes exposure to the heat
the upper surface of the charge forms into a cake. This cake is removed to one
side and resembles lumps of coke, and the surface then exposed cakes over, and so
on until the whole charge has become caked. The charge is balled up, as it cakes
in sufficient quantities, and is rolled out into bars; and the bars thus produced are
used as puddled bars and subsequently dealt with in the ordinary manner for the
production of merchant bars, plates, sheets, or the like.
The quantities of the different ingredients of a charge may be varied considerably
without departing from the nature of the invention, but I find that the following
parts by weight of the different ingredients make a good ordinary mixture and a
convenient quantity for a single charge, namely:-three hundredweight of cast iron
swarf, four hundredweight of iron scale or oxide such as the scale or oxide from

page_text: ironworks and forges, tube works, blacksmiths' shops, edge tool works, and the like,
and one hundredweight. of coke dust. The ingredients are thoroughly mixed
together before being charged into the furnace. They may be mixed by being
turned over with a shovel, or in any convenient manner.
As above indicated, an ordinary puddling or ball furnace may be used for
charging the mixture into and balling it up in. I find it, however, convenient to
use a furnace, such as illustrated by the drawings herewith, in which two charging
and balling doors are used instead of one only.
Figure illustrates such a furnace in longitudinal section, and Figure 2 is a
sectional plan thereof.
The furnace bottom A extends from the fire-bridge B to the back of the
chimney C. In addition to the ordinary charging and balling door D, there is a
supplementary charging and balling door E.
The door openings are indicated by broken lines only in Figure 1, as they are
formed through the side of the furnace not shewn in such view. No claim is made
in respect of this furnace as a similar furnace has been used before as a puddling
furnace.
In using the furnace with the two doors as illustrated the material is thrown in
by means of a shovel through both doors, and is thrown so as to lie fairly evenly
over the whole bottom of the furnace except for that portion of it which is imme-
diately below the chimney flue and which forms the bottom of the chimney. As the
material cakes it is balled up through both the doors; but the balls are more
conveniently drawn through the ordinary door, that is to say, the door D, as in
getting a ball out through the door E the operator would be standing in front of
the door D. By using a furnace with two doors as described a larger amount of
work can of course be got through than when a furnace with a single door only is
used; and, moreover, the material can be conveniently charged over the portion of
the furnace bottom which is near to the chimney, and thus the heat from the grate
be more thoroughly utilized.
Considerable economy results in the use of cast iron swarf in combination with
iron oxide or scale, in producing bars (corresponding in character and purpose to
puddled bars) according to this invention, owing to the quantity of iron which is
recovered from the oxide or scale. I find that in a ton of swarf charged into a
puddling furnace, and worked up apart from any admixture of oxide or scale
and carbon therewith (that is to say puddled in the ordinary manner), about
five hundredweight would be lost in the yield of puddled bars compared with the
original weight of the swarf; but in utilizing the swarf in the manner of this
invention (and with the ingredients of the charge in the proportions above specified)
there is a gain in the yield of bar, owing to the quantity of iron recovered from the
oxide or scale, of five hundredweight for every ton of swarf used; so that for
every ton of cast iron swarf utilized according to my invention there is a yield of
ten hundredweight of bar more than the yield of puddled bar from the same quantity
of cast iron swarf used without the oxide or scale and carbon as when it is puddled in
the ordinary manner in the manufacture of puddled bars. The great advantage in
the invention consists, of course, in the fact that it affords means of recovering a
large quantity of iron from the oxide or scale and converting it into wrought iron;
and thus wrought iron of a good quality is produced at a considerable reduction in
cost compared with its production by puddling from pig iron or from cast iron
swarf. The cinder produced in balling up the iron, in manufacturing it according
to this invention, is tapped after the charge is withdrawn, and is of a quality which
allows of it being used for fettling puddling furnaces.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The manufacture of wrought iron from a mixture of cast iron swarf, iron oxide
or scale, and carbon, substantially as described.

page_text: 2. The manufacture of wrought iron from a mixture of cast iron swarf, iron oxide.
or scale, and coke dust, substantially as described.
3. The manufacture of wrought iron by heating a mixture of cast iron swarf, iron
oxide or scale, and carbon reduced to small particles, and preferably in the form of
coke dust, upon the bed of a reverberatory furnace such for instance as a puddling
or ball furnace, and balling it up as it cakes, substantially as described.
Dated this 4th day of March 1893.
STEPHEN
WATKINS,
Wolverhampton, Agent for the Applicant..