IMPROVEMENTS IN THE MANUFACTURE OF MALLEABLE IRON, AND IN THE PROCESS OF REHEATING THE SAME FOR THE PURPOSE OF ROLLING OR HAMMERING IT
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by Carl Friedrich Claus at the
Office of the Commissioners of Patents, with his Petition, on the
30th March 1868.
I, CARL FRIEDRICH CLAUS, of Middlesbrough-on-Tees, in the County
of York, Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF MALLEABLE IRON, AND IN THE
PROCESS OF REHEATING THE SAME FOR THE PURPOSE OF ROLLING OR HAMMERING
IT," to be as follows:-
My Invention consists,―
First. In the application of a flux of chloride of calcium or fusible
mixtures of lime and common salt (chloride of barium could also be
used, but I prefer chloride of calcium) during the operation of puddling
iron for the purpose of purging the iron operated upon from phosphorus
and sulphur, and of protecting the iron or the carbon in the iron against
the too rapid oxidation by the atmospheric air.
Secondly. In the exclusion of all siliceous materials as far as it is
practically possible from the iron when it is being operated upon in the

page_text: manner described hercin, or when the above-named fluxes are being
used in the operation of puddling; therefore I only use those materials
in the construction of the furnaces which are neither acted upon by
oxide of iron, pig iron, nor the fluxes named above, and which do not
contain any silicic acid, such as alumina, magnesia, or lime. As the
only exception to this I use steatite or serpentine, which, although
silicates of magnesia are not acted upon by pig iron or oxides of
iron.
Thirdly. My Invention consists in the addition of chloride or oxides,
manganese, or the descicated refuse liquor of the manufacture of chlorine
to the above-named fluxes when they are used in the operation of
puddling..
Fourthly. As it is the practice in the manufacture of malleable iron
to add to the pig iron under treatment for the purpose of puddling a
certain quantity of an oxide of iron, I only select when puddling on
the principle and with the fluxes described herein, those oxides which
are as free as possible or practicable from compounds of silicium, and
prefer such oxides as are produced by oxidation of metallic iron. As
one source of such oxides I propose to granulate, as has been done
before and for a similar purpose, by pouring molten, pig, or cast iron
upon a table revolving at great speed or down a shot tower, in the
manner well known to the iron manufacturer, with that difference only
that I seek to burn or oxidize the small globules of iron during their
descent as much as possible. This I effect by bringing the globules of
molten iron in a closed space in contact with heated air during their
descent. A chamber intercepting the hot blast from a blast furnace
and before it enters the latter could be used for that purpose. Provision
should, however, be made to allow the globules to solidify before
reaching the ground so that they remain in the form of fine shot.
Fifthly. After having mixed pig iron and oxides of iron or granulated
iron and flux together, in proportions best indicated by practice, I
introduce the same into the puddling furnace and carry on the process
of puddling as has been practiced hitherto with the ordinary materials.
When the balls or masses of malleable iron have been withdrawn from
the furnace, and have been hammered or rolled, and when the bars have
been cut and piled and are ready to be heated for a second or third
rolling operation they are usually placed in piles in rcheating furnaces.
In order to protect the iron in these heating furnaces from oxidation,

page_text: and to remove any oxides of iron already formed and adhereing to the
iron I cover the same with the fluxes named above, namely, chloride
of calcium or mixtures of chloride of sodium and lime. The same
fluxes may serve several times over, and when they are charged with a
sufficient quantity of oxide they may be used in the puddling furnace
as a source of oxide of iron, while at the same time the flux itself is
further utilised.
The refuse flux or slag derived from the puddling furnaces I employ
in the ground state in the blast furnace mixture as additions to the
usual charge, and as specified in another Specification of mine lodged
at the Great Seal Patent Office this day, with a petition for a Patent
for improvements in the manufacture of iron.