Improvements in the Process and Apparatus for Manufacturing Copper Tubes, Sheets, Strips and Wires by Electrolysis.
Year: 1890

page_text: Date of Application, 21st Nov., 1890-Accepted, 22nd Aug., 1891
COMPLETE SPECIFICATION.
Improvements in the Process and Apparatus for Manufacturing
Copper Tubes, Sheets, Strips and Wires by Electrolysis.
I, ALEXANDER STANLEY ELMORE of Spring Grove, Hunslet, Leeds in the
County of York, Electrometallurgist, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement :—
It has been proposed to manufacture tubes by electrolytically depositing metal
on revolving mandrils and rendering the deposited metal firm, sound and compact
by burnishing it as it is deposited by means of burnishers caused to travel to and
fro along the surface as it revolves. The tubes thus electrolytically manufactured,
in their entire condition, are available as strong and sound pipes or conduits for
fluids, or, according to descriptions given in other Patent Specifications, they are
divided by straight or helical cuts and unbent so as to form sheets, strips or wires
of sound and homogeneous character. The present invention consists in improve-
ments in this process and in the apparatus by which it is conducted.
The process according to my present invention for depositing copper is conducted
as follows:- first prepare an externally turned and polished mandril of iron or
steel, preferably hollow for the sake of lightness and I fix this on a non-conducting
spindle which may be of wood. I mount the mandril spindle in non-conducting
bearings, which may be of glass, in an electrolytic bath, connecting the mandril
by a brush to one terminal of a voltaic battery, dynomo electric machine or other
source of electricity, so as to form a cathode, and connecting a suitable anode to
the other terminal.
1 form the anode of two sheets of copper one on each side of the bath, and I
charge the bath with a solution of double cyanide of copper and potassium, the
solution containing about 1 part by weight of the salt to 20 parts of water, and
the temperature being preferably about 55° to 60° C. The mandril having been
caused to revolve in this bath with the clectrical action continued for about a
quarter of an hour, becomes coated with a layer of copper, and then it is taken
out and exposed for about the same time to the air, by which the surface becomes
oxidised, so that another layer of copper deposited on it will not adhere to it. The
mandril thus prepared with an oxidised coating of copper, is now placed in
another bath which has for its anode a perforated plate of copper supported at a
little distance above the bottom of the bath and carrying a thick layer of granulated
copper. In addition to this anode, plates of copper may be placed on the bottom
plate so as to stand upright on each side of the mandril. The solution in this bath
consists of sulphate of copper with a certain amount of free sulphuric acid. The
proportions may be varied, but I find that in starting the bath, about 3 parts by
weight of sulphate of copper crystals and 1 part of acid to 20 parts of water
make a good mixture, to which from time to time a little acid has to be added.
The mandril is caused to revolve in this bath and the burnishing tool is caused to
travel to and fro along the surface of the deposited metal by apparatus which I
shall hereafter describe, until the desired thickness of metal is deposited. When
additional layers have to be deposited, the surface of each layer has to be treated
to prevent adhesion of the next layer. This can be effected by running off the
contents of the bath and exposing the metal for a short time to oxidation or by
varnishing the surface of the deposited metal with a thin coating of solution of
wax in alcohol. When no particular regard is to be had to the surface polish, a
rapid and easy method of preventing adhesion is simply to reverse the electrical
current for a very short tinie, thus producing a film of oxide on the surface of the
metal.
. When the metal is deposited to sufficient thickness to form a tube, or when a

page_text: sufficient number of successive thicknesses have been deposited, the mandril with
the metal on it is removed from the bath and subjected, in a machine presently to
be described, to pressing rollers which are made to travel along it longitudinally.
These rollers by somewhat extending the periphery of the deposited metal, loosen
it from the mandril, so that it can be readily removed therefrom. The tube thus
removed from the mandril, may be used as a pipe or it may be cut longitudinally
and unbent to form a sheet or cut helically to form a long continuous strip or a rod
which can be drawn to wire, and when several thicknesses have been deposited,
they can all be cut at one operation producing a number of sheets, strips or
wire rods.
Fig. 1 of the accompanying drawings is a plan, and Fig. 2 is a longitudinal
section showing the first, second and part of the third of two continuous rows of
electrolytic baths for the deposit of the copper on the revolving mandrils, with the
gearing for causing the mandrils to revolve and the burnishers to travel to and
fro along the surface of the deposited metal. Figure 3 is a transverse section
on XX to an enlarged scale. The baths A may be made of wood made water-
proof by a lining of resinous or like material.
A little above the bottom of each bath is supported a perforated plate B of
copper covered with
thick layer C of granulated copper, and standing on the
plate B are two upright plates D of copper, one on each side of the mandril E on
which the copper is deposited. A shaft F, driven by any suitable motor, is
mounted between the two rows of baths and extends along them, having on it
pullics G which by belts drive pullies H, one for each bath, and from the spindles
of these pullies the mandrils E are driven by chain gearing. The spindle of each
mandril, which is of wood turns in bearings one at each end consisting of two
plates e of glass placed at an angle in a wooden block and over the spindle is a
bar e¹ of wood to prevent it from being lifted out of its bearing. Over the central
space, between the two end baths, is mounted a screwed spindle K, connected by
a shifting clutch to either of two pullies LL' revolving in opposite directions.
The clutch is jointed to a lever M which is surmounted by a tumbling weight,
and is linked to a rod N that extends above the screw K and has on it two
collars nn fronted by springs. A cross head O forms the nut of the screw K, and
has an arm o standing up from it and embracing the rod N. The cross head O is
fixed on a sliding rod P which extends the whole length of the row of baths and
has fixed on it cross heads O' one for each bath. These cross heads O¹ as well as
the first cross head have removable arms O2 projecting from them and on
these are pivotted the burnishing tools Q which can be adjusted along slots in the
arms O so as to press obliquely on the surface of the mandril E their pressure
being regulated by an elastic band g which can be strained more or less to catch
on one or other of a set of hooks 7. Assuming that the screw K is driven by the
pulley L so as to turn in the one direction, causing the cross head to travel
towards the right and with it the rod P and all the other cross heads O¹ and their
arms O so that all the burnishing tools Q move along the surfaces of their
respective mandrils which at the same time are caused to revolve by
their connections to the shaft F, then, when the arm o approaches the stop collar n
it first compresses the spring, then moves the rod N causing the lever M. to tumble
over, disengaging the clutch from the pulley L and engaging it with the
oppositely revolving pulley L'. The rotation of the screw K being thus reversed,
the cross head O, the rod P and all the other cross heads O' arms O2 and their
burnishing tools Q now travel back, until the arm o acting on the stop collar n
again causes reversal of the screw K.
Figure 4 is an end view partly in section, Figure 5 is a side view and Figure
is a plan of the roller apparatus whereby the shell of deposited metal is released
from the mandril. The mandril E with the shell of metal on it is mounted
between centres R R which are on slides adjustable in height by screws r². A
slide S which by means of a screw S¹ can be moved along the bed of the machine,
carries three rollers T' T' T'. The two lower rollers T T' can be adjusted to or

page_text: from the central line of the bed by a right and left handed screw t.
The upper
roller T³ is carried by a lever U which is pirotted to a vertical slide u capable of
being raised or lowered by a screw ¹, and the other end of this lever is adjustably
linked to another lever V carrying an adjustable weight u. The mandril E with
its coating of deposited metal being caused to revolve, the slide S with its rollers
is at the same time caused to travel along the bed of the machine, and the pressure
of the rollers, by extending the periphery of the metallic shell, loosens it from the
mandril.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The herein described process for manufacturing copper tubes by electrolysis,
that is to say, preparing mandrils by treatment in baths of cyanide of copper,
mounting these mandrils in electrolytic baths charged with acidulated solution of
sulphate of copper and having granulated copper and copper plates arranged as
anodes, and the mandrils as cathodes connected to a source of electricity, causing
the mandrils to revolve while burnishing tools travel to and fro along their
surfaces, and finally, when the deposit is of the desired thickness, removing the
mandrils and their coatings from the baths and subjecting them to the pressure of
rollers travelling along their length so as to loosen and release the deposited
tubes.
2. In applying the process above referred to for electrolytically depositing
successive layers of copper on the mandrils above referred to, treating each
deposited layer with varnish or oxidation so as to prevent adhesion of the next
layer, substantially as described.
3. For driving the mandrils in a number of electrolytic baths arranged in two
parallel rows, the combination of the central shaft F, the pullies G and H, and the
chain gearing to the mandrils, substantially as described.
4. For effecting the to and fro traverse of the burnishing tools for a number of
electrolytic baths arranged in two parallel rows, the combination of the screw
spindle, clutch & reversing pullies LL' tumbling lever M, rod N and its
collars nn', cross head O its arm o the rod P and cross heads O' and arms O³
substantially as described.
5. For loosening the tubes of deposited metal from the mandrils, the roller
machine substantially as described with reference to Figures 4, 5 and 6.
Dated this 21st day of November 1890.
ABEL & IMRAY,
Agents for the Applicant.