An Improvement in the Manufacture of Soft Metal Tubes.
Year: 1894

page_text: Date of Application, 25th May, 1894-Accepted, 30th June, 1894
COMPLETE SPECIFICATION.
An Improvement in the Manufacture of Soft Metal Tubes.
I, WILHELM DROESER, of Earls Court Square, in the County of London,
Manufacturers' Agent, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described in and by the
following statement :-
This invention relates to an improvement in the manufacture of lead and
analogous soft metal or alloy pipes or tubes, (the same being hereinafter referred
to as the soft metal tube) with the object of rendering such tubes the better
enabled to resist destruction from within by suddenly varying internal pressures of
water or other liquid circulating therethrough or by the expansion of liquid
becoming frozen therein, and destruction from without by the rodentia order of
animals or by the penetration of nails and the like, and distortion of shape upon
being bent, (to which disadvantages such tubes are especially subject,) without
affecting the bending pliability of such tubes.
To this end, the invention consists essentially in the combination with the soft
metal tube, of a helically coiled wire, rod, bar, band or ribbon (the same being
hereinafter referred to as the wire or ribbon) of a metal or an alloy of a higher
melting point than the soft metal with which it is combined and of a greater
toughness and tenacity adapted to offer the desired increased resistance, (the same
being hereinafter referred to as the tougher metal,) such wire or ribbon of the
tougher metal being incorporated with the soft metal tube within the substance
thereof so as to be protected thereby from oxidation, at the time of manufacture.
I prefer to employ steel as the tougher metal, but other metals or alloys of
metals of an appreciably higher melting point than that of the soft metal with
which it is incorporated and of an appreciably greater toughness and tenacity, and
the desired properties of which will not be destroyed or materially decreased by
the melting point of the soft metal, may also be employed.
The wire or ribbon of the tougher metal may be of an elliptical, or of a flat-sided
and round-ended, or of a flat ribbon-like section applied with the major axis or
length of its section parallel with the axis of the soft metal tube; it may, however,
be of a circular, semi-circular or other section, and may be solid or tubular or
perforated with through holes. It may be applied nearer adjacent to the outer
periphery of the soft metal tube than to the inner periphery thereof, so as, while
still offering its maximum increased resistance, relatively to that of the soft metal
of the tube, to internal pressure, it will the sooner offer its resistance to any
rodentary attack from without, and will the better lessen the liability of penetration
by an ill-directed nail or cutting instrument; it may, however, be applied
equidistant from the peripheries of the soft metal tube, or nearer to the inner
periphery than to the outer periphery thereof.
The pitch of the helix of the coil of the wire or ribbon of the tougher metal
should be sufficient to enable the molten soft metal to pass freely between the
adjacent coils and to wholly surround each and all parts thereof, so that the soft
metal will be continuous throughout the whole length of the tube and so as to
avoid liability of the formation of any interstices between the soft and tougher
metals, and to combine the same in one coherent mass.
The coil of wire or ribbon may be applied in one continuous length or in
sectional lengths. It is preferably arranged concentric with the tube, and if two
of such coils be used, as they may be, they also are both preferably arranged
concentric with the tube, the one within but independent of the other, both being
entirely enclosed by the soft metal of the tube.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is ;-
In combination, a lead or other soft metal pipe or tube, and a helically coiled
wire, rod, bar, band or ribbon of steel or other metal of a higher melting point
than that of the soft metal tube and of a greater toughness and tenacity, the wire
or ribbon of the tougher metal being incorporated with the soft metal tube within
the substance thereof at the time of manufacture.
Dated this 24th day of May 1894.
'
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C., Agents for the Applicant.