Year: 1887

page_text: Date of Application, 10th May, 1887.
Specification Accepted, 17th June, 1887.
I ALFRED MANNESMANN, of Strassburg, Alsace, in the Empire of Germany, sub-
lieutenant in the 47th Infantry regiment, 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 provide a remedy for the inconveniences inherent
to the use of iron and steel wire as well as of copper wire for telephonic, telegraphic
and other cognate purposes connected with the province of electricity; iron and steel
wire not having an adequate conductive power, while copper wire, owing to the
insufficient elasticity of copper, is liable to sustain injuries when, used for the purpose
of spanning long distances."
To the aforesaid end I use iron or steel tubes, by preference such as are made without
seam in accordance with the oblique or diagonal rolling process forming the subject of
an Invention communicated by Reinhard Mannesmann and Max Mannesmann to
Herbert John Haddan, for which letters-patent dated January 27th 1885 Number 1167
have been granted to the aforesaid Herbert John Haddan. pour molten copper into
the hollow of such tubes, or else I insert in an iron or steel tube of the aforesaid
description a solid or hollow copper rod and I join or incorporate the two kinds of
metal with each other by rolling, pressing, hammering or drawing; or else I place
a steel core in a copper tube which in its turn I insert in a steel tube of proportionately
larger diameter, and having done so, I produce the agglutination of the various strata
of metal to one another by pressing or hammering them, having previously imparted
to them a suitable temperature. By this second method I obtain a solid body made
up in such a way that there is a thickness of steel adjacent to the copper tube both
within and without, so that when such copper tube is subsequently rolled, drawn out
or otherwise turned into wire, it is stretched more uniformly than when iron or steel
adjoins it on one side only. In order more completely to achieve the object aimed at,
I insert a series of copper and steel tubes alternately into one another, so that there
are in the combination produced by such insertion alternate layers or strata of copper
and steel, and having done so, I bind up the various metals into one solid body by
pressing, hammering or any other appropriate method..

page_text: When, in the course of the drawing process, an equal pressure is brought to bear
upon both the copper and the iron or steel portion of the composite body thus formed,
the copper has a tendency to stretch or extend more rapidly than, and gradually to
project beyond, the iron or steel portion of such body. With a view to prevent this,
and also to preclude atmospheric air from insinuating itself between the various layers
or strata of metal that make up the aforesaid composite body, I close up the ends of
such body, prior to exposing it to the heat required for drawing, rolling or otherwise
working it, so as to reduce its diameter to the desired gauge. In order to impart a
uniform thickness to the copper portion of the body, I employ Mannesmann's oblique-
rolling process hereinbefore alluded to, lieu of the ordinary method of rolling. By
this means the pressure upon the copper core may be readily reduced, because the
external iron or steel tube has a tendency to preserve the proportion between its
internal and its external diameter intact, be the wire reduced by the rolling process to
ever so small a diameter; and at the same time room is left for the copper to stretch
in the same proportion as the iron or steel surrounding it. If tubular bodies be
subjected to the same process, a wire may be produced which remains hollow, even
though its thickness be reduced to the utmost limit.
Besides the advantages stated in the foregoing, the wire produced by the method
herein set forth possesses a notable superiority as compared with the usual description
of compound wire in which the core consists of iron or steel and the coating or
integument of copper; for in suchlike wire the copper coating, owing to its elasticity
being less than that of the core, is gradually disintegrated by the action of the
atmosphere and detached from its core, whilst in the copper steel wire or steel copper
steel wire prepared in accordance with my Invention, the great elasticity of the steel
coating enables the molecules to ever resume their original position, thus preventing
the wire from being in any way injuriously affected by succeeding changes of
temperature.
Having now particularly described and ascertained the nature of my said Invention,
and in what manner the same is to be performed, I declare that what I claim is:
1. Imparting to copper wire an increased tensile strength by furnishing it with a
coating or integument of iron or steel in the manner herein set forth, thereby protecting
it from external injury and enabling it to span longer distances than can be spanned
by ordinary wire.
2. Combining iron or steel tubes with copper cores or copper tubes, and thereby
forming solid or hollow copper steel wire or steel copper steel wire, in the manner
and for the purpose herein set forth.