COMPLEIE SIMULT
Year: 1894

page_text: COMPLEIE SIMULT
Improvements in the Manufacture of Steel."
(A communication by ERNST BERTRAND, Manager, and OTTO THIEL Chief Engineer
of Kladno, Bohemia in the Empire of Austria)
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of the Agency for Foreign Patent
Solicitors, 6, Lord Street, Liverpool and 6 Bank Street, Manchester both in the
County of Lancaster and 323 High Holborn in the County of Middlesex, Civil
Engineer, 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 :-
The invention consists in a combination of several open-hearth furnaces, arranged
to work together in such a manner that one furnace performs the melting of the
metal, the oxidation and removal of the silicon and of a part of the carbon and
eventually-of-the phosphorus contained in the metal, and that then the so purified
metal is tapped off and let down by means of troughs or runners into a second open-
hearth furnace, in which latter the process of purification is brought to an end and
the heat finished in the usnal manner by addition of ferro-manganese, spiegeleisen,
etcetera, etcetera.
In order that the metal may freely flow from the first of the above mentioned
furnace-hearths to the second, it is necessary to situate the first one upon a corre-
spondingly higher level than the second.
The-lining-of-the-furnaces-may, -in-case-a-removal-of-phosphorus-from-the-metal
is-not-intended-baeid-or-basie,-while-in In all cases, where the metal to be treated
contains more or less phosphorus or sulphur, a basic lining will be necessary.
By this combination of a number of open-hearth furnaces, situated in different levels,
the different stages-of-the--process;-and-especially-the-removal--of-the-silicon-and
phosphorus-from-the-metal-may-be-performed--separately-upon--separate-hearths,
and, farther, the metal, when flowing from one hearth to the other, may be perfectly
freed from the resulting acid-or basie slags, so that the purified metal only perfectly
free of slag may flow down into the lower hearth, where the heat is to be finished and
the last trace of phosphorus eliminated.
By performing the different operations of the process in separate-open-hearths,
and--freeing-the-metal from-the-resulting-slags, it is evident that-each-operation
may-be-performed-with-much-greater-accuraer-and-perfection,-whereby-the-quality
and-uniformity-of-the-resulting-product-will-be-materially improved.
Further, it will-be-evident--that-since-the-slag-is-perfectly-separated-from the
metal-on-its-way-from-one-furnace-to-the-other-each-furnnee-will contain maeb-less
slag-than-under-ordinary-circumstances;-and-consequently comparatively-less-lime-
011

page_text: stone,-lime-or-other-additions-will-be-necessary-for-the-neutralisation of the slag;
whereby-the-mass-of-the-slag-resulting-in-each-furnace-is-further-redused:
Since the metal in the furnace or furnaces is covered with a thinner sheet of slag,
the flame will naturally be enabled to act much more energetically upon the bath,
thereby causing the process to progress much more rapidly, thus materially reducing
the duration of the heat and consequently the consumption of fuel.
The diminished quantities of slag in the furnaces and the shorter duration of the
heat further result in a proportionate increase of output and a saving of furnace lining,
as also in a decrease of the percentage of loss-and-a-saving of ferro-manganese,
spiegeleisen, etcetera, etcetera, since the decreasing quantities of slag will
naturally absorb proportionately less quantities of the oxides of iron and
manganese.
The arrangement of the different open-hearth furnaces will naturally depend upon
the nature and chemical composition of the pig-iron and scrap that are to be
worked, the percentage of silicon and phosphorus they contain being here of decided
In-case-the-materials-to-be-worked-contain-solely phosphorus-and-but-little-or-no
influence.
silicon,-two-open-hearth-furnaces,-arranged-as-shown-in-Figure-1,-will-suffice.
situated-furnace-A,-while-the-lower-furnace-B-is-designed-to-finish-the-heat.
The-metal-will be molten-and-the-phosphorus-it-contains-removed-in--the-higher
In-ease, however, the metal-to-be-worked-contains-large--percentages-both-of
silicon-and-of-phosphorus, an-arrangement-with-three-open-hearth-furnaces-situated
in-three-different-levels,-as-shown-in-Figure-2,-will-be-desirable.
The--furnace--A--is;-in-this-ease;-designed-for-the-melting-of-the-metal-and-the
removal-of-the--silicon;-the--furnace--B-for-the-removal-of--the--phosphorus,--and
the-furnace-C-for-the-finishing-of-the-heat.
The-removal--of-the-carbon-contained-in-the-metal may be performed wholely-or
partly in either-of-the-three-furnaces,-just-as-the-eireumstances-demand.
A-third-case-calling-for-another-arrangement--takes-place-when-a-portion-of-the
metal-to-be-worked contains-a-high-percentage of silicon,-while-another-portion-of
the-metal-is-high-in-phosphorus.
Here-a-modified-arrangement,-as-shown-in-Figure-3,-with-two-furnaces-A¹-and-A
apon-a-higher-level-and-of-one-furnace-B-upon-a-lower-level,-will-be-advisable.
The-upper-furnace-A¹-is-designed-for-working-the-metal-containing the silicon,
and-the-furnace--A2-for-the-metal-containing the phosphorus. After-performing
these--two-operations--in--the--respective-furnaces,-the--metal--is--run-from--both
A-and-A-together-in-the-lower-furnace-B-with-a-hearth-of-correspondingly-larger
dimensions;-where-the-heat-is-then-finished-in-the-usual-way.
It-is-however;-ander-certain-circumstances, also-fensible-to I may perform the
removal of silicon and phosphorous from the metal by means of the arrangement
with only two furnaces, as shown in Figure 1, although more furnaces may be used.
In this case chiefly the pig-iron containing silicon and phosphorus is charged into
the upper furnace A, while the scrap or white pig-iron containing little or no
silicon is charged into the lower furnace B.
After melting and removing the silicon and a great part of the carbon and
phosphorus from the metal contained in the hearth of furnace A, the metal in
furnace B being meanwhile molten, the contents of furnace A are run down into
furnace B and the phosphorus still remaining in the thus united two metals, is
finally and perfectly eliminated in the lower furnace B, and the heat finished in the
usual manner.
Naturally; this arrangement of a combined open-hearth process by means of a
number of furnaces working together and situated in different levels permits
a-great variety of modifications tee-numerous-to-specify-in-detail,-so-that-the-eases
to
contained--in-the-above-description-ean-only-lay-down-the-general--principles-upon
whie-the-process-is-based. I am aware that it has been heretofore proposed
perform the operations of removing the phosphorus, silicon and the like impurities
in separate furnaces; that is to say the phosphorus in one furnace, the silicon in

page_text: another and so on. Hence I desire to confine my process and any modification
thereof to cases in which the silicon and a great part of the phosphorus are
eliminated in the same furnace or furnaces and the process of purification (after
removal of slag) is completed in another furnace and I disclaim any modification
which is inconsistent with this.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondents, I declare that what I claim is :-
t. The improvement in the manufacture of steel consisting in performing the
different operations of the process as above indicated in separate open-hearths,
substantially as described.
2. In-the-manufacture--of-steel-the--combination--of--two-or-more-open-hearth
furnaces,-united-in-a-group-and-situated-in-levels-of-different-elevation, so that the
metal-may-be--run-from--one-hearth-level-to-another-in-a-fluid-state-by-means-of
troughs-or-runners, and the slag-be-perfectly-separated-from-the-metal-on-its-way
from-one-furnace-to-the-other-substantially-as-described-and-shown.
Dhim th
T
1004
WM. P. THOMPSON & Co.
Agents.