Improvements relating to the Lining of Conduits for Electric Conductors.
Year: 1890

page_text: Date of Application, 6th May, 1890-Accepted, 27th Dec., 1890
COMPLETE SPECIFICATION.
[Communicated from abroad by DAVID BROOKS, Junior, of No. 107, South
3rd Street, Philadelphia, United States of America, Inventor.]
Improvements relating to the Lining of Conduits for Electric
Conductors.
1, HENRY HARRIS LAKE, of the firin of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, in the County of Middlesex, 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 :-
My invention consists of a novel manner of introducing a lining of protecting
material or composition into a conduit for electric conductors as will be hereinafter
set forth.
In the accompanying drawing,
Figure 1 represents an apparatus employed in carrying my invention into effect.
Figure 2 represents a perspective view of a portion of the same.
Similar letters of reference indicate corresponding parts in the drawing.
In carrying out my invention, I prepare a conduit or duct for electric conductors,
to receive protecting materials and cables of electric wires as follows:
Dry swabs of cotton or cotton waste aro run through the conduit, so as to dry
the same or absorb the moisture that it may contain. If desired, this may be
accelerated by the use of a hot air blast.
I then introduce into the conduit a composition of non-fusible powder or oil, or any
plastic material such as powdered soap-stone or soap-stone and rosin-oil, either of
these being preferred, since either or both prevent water or moisture from passing
through a good layer or coating.
It may be convenient to introduce the protecting material into each section of
the conduit, as it is laid, care being taken to leave sufficient space for the cable
to enter subsequently. The material may also he introduced into the splice boxes,
and the like.
The material has for its object the filling of the space left between the cable
and sides of the conduit, to prevent the circulation of air and gases, and also
prevent the introduction of water or moisture and foreign matter into the conduit,
the material owing to its plastic or movable nature, also allowing the cable to
be drawn out and replaced as desired.
The cable may be of dried fibrous, tissue-covered rubber insulation or other suitable
kind.
I now employ a movable tank A, containing a reel B, on which is wound a wire or
other rope C, said tank being supplied with the protecting material.
Secured to the rope at intervals, are buckets or carriers D, to whose peripheries
are attached lugs E, whereby said buckets are prevented from dropping into crevices
or separated joints in the length of the conduit."
The rope is drawn from the reel in the tank, through the discharge pipe F,
which is in communication with said tank and the conduit, and likewise drawn into
and through the conduit, whereby the material is conveyed into the latter.
The rope should be pulled through the conduit for some time after the material
appears at the end G of the conduit, as some of said material will return over the.
buckets, the latter being of such diameters that when the cable is subsequently
introduced into the conduit, sufficient space will be left for the cable to enter the
same from one end to the other.
The rope with the buckets thereon are drawn through the conduit, and as the
said buckets are of less diameter than the conduit, while the greater portion of the
composition is drawn out with the buckets, the walls of the conduit are effectively

page_text: lined or conted with the composition. The cable passes through the tank A and is
then drawn through the conduit and occupies the central opening or space through
which the buckets have passed. The said cable in passing through the plastic material
will also become coated with the said material which is drawn into the conduit.
I am aware that it is not now to employ as insulating material, soap-stone with
either paraffine or crude petroleum, but as both these oils are lighter than water, they
would not serve the purpose intended by my invention, wherein the mixture placed
in the conduit in the manner described, serves not as an insulator, but as a protector
to prevent moisture or decay.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
First. The herein-described method of preparing a conduit for electric wires,
consisting first in thoroughly drying the interior of said tube by passing through
the same, dry waste and hot air, then drawing into the conduit and along the
interior of the same, a sufficient quantity of soap-stone and rosin oil or their
equivalents by means of a rope with carriers to fill said conduit, and lastly, with-
drawing said rope and carriers, substantially as described.
Second. The method of drying a conduit for an electric wire or cable, consisting in
introducing into the same, a swab of absorbing material or hot air, and following
with a protecting material, substantially as described.
Third. The method of filling an air space in a conduit for an electric wire or cable,
which consists in introducing into the same a non-fusible powder or powders mixed
with an oil, substantially as described.
Fourth. The method of introducing a protecting material into a conduit for an
electric wire or cable, consisting in passing such material from a tank by means of
buckets or carriers, which are attached to a rope primarily within said material,
substantially as described.
Fifth. The method of introducing a protecting material into a conduit for an
electric wire or cable, consisting in passing such material into the conduit by means of
carriers primarily in the tank containing the material, and subsequently introducing
the electric wire or cable, substantially as described.
Sixth. The method of introducing filling and protecting material into a conduit for
an electric wire or cable consisting of directing such material into the sections of the
conduit as laid, and when the conduit is completed, drawing the electric wire or cable
through the same, and thereby filling all space in said conduit, substantially as
described.
Dated Gil ....1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.