AN IMPROVEMENT OR IMPROVEMENTS IN THE MANUFACTURE OF TUBES OF COPPER AND ALLOYS OF Copper
Year: 1855

page_text: LETTERS PATENT to John Wilkes, of Birmingham, in the County of
Warwick, Manufacturer, for the Invention of "AN IMPROVEMENT OR
IMPROVEMENTS IN THE MANUFACTURE OF TUBES OF COPPER AND ALLOYS OF
Copper."
Sealed the 20th May 1856, and dated the 26th November 1855.
PROVISIONAL SPECIFICATION left by the said John Wilkes at the Office
of the Commissioners of Patents, with his Petition, on the 26th November
1855.
I, JOHN WILKES, of Birmingham, in the County of Warwick, Manufac
turer, do hereby declare the nature of the said Invention for "AN IMPROVE-
MENT OR IMPROVEMENTS IN THE MANUFACTURE OF TUBES OF COPPER AND ALLOYS OF
COPPER to be as follows:-
My Invention consists in manufacturing tubes from cast or other hollow
cylinders of copper or alloys of copper by the process of rolling, in the manner
herein-after described. In reducing and elongating the said hollow cylinders,.
so as to produce tubes therefrom, I employ rolls, having grooves on their
cylindrical surfaces, the said grooves being of a nearly semicircular transverse
section, so that the grooves in the upper and lower rolls when opposed to each
otlier present a nearly circular opening between them. Instead, however, of
making the said grooves of a truly semicircular section, I make the said
grooves of somewhat less depth than that of a semicircle, so that the opening
formed between them is of greater diameter horizontally than it is vertically:

page_text: I pass the hollow cylinder to be made into a tube between rolls made as
described, each pair of grooves through which the cylinder is passed being of
less size than the previous pair. A mandril is placed in the interior of the
hollow cylinder, and the said cylinder is passed through the rolls. I.cause the
said cylinder to perform a quarter revolution on its axis, and again pass it
between the rolls, the same grooves being employed as before. That portion
of the cylinder which was least acted upon by the first rolling is most acted
upon by the second, and every part of the tube or cylinder is by the two rollings
equally or nearly equally acted upon. I afterwards pass the cylinder in a
similar manner through grooves of diminishing size until the said cylinder bas
been converted into a tube of the required dimensions. The mandril may be
removed from tubes made according to my Invention without difficulty.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Wilkes in the Great Seal Patent Office on the 24th
May 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
WILKES, of Birmingham, in the County of Warwick, Manufacturer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of November, in the year of our
Lord One thousand eight hundred and fifty-five, in the nineteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Wilkes, Her special licence, that I, the said John Wilkes, my
executors, administrators, and assigns, or such others as I, the said John
Wilkes, my executors, administrators, and assigns, should at any time agreo
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "AN IMPROVEMENT OR IMPROVE-
MENTS IN THE MANUFACTURE OF TUBES OF COPPER AND ALLOYS OF COPPER," upon the
condition (amongst others) that I, the said John Wilkes, my executors or
adıministrators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be perfornied, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said John Wilkes, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described, and ascertained in and by the following
statement thereof, that is to say:-
My Invention consists in manufacturing tubes from hollow cylinders of
copper or alloys of copper (whether the said cylinders be cast or otherwise
formed by the process of rolling, the said process being conducted in the
manner herein-after described, and illustrated in the accompanying Drawing.
In elongating and reducing the diameter and the thickness of the said hollow
cylinders, so as to convert them into tubes, I employ rolls having the con-
struction illustrated in the accompanying Drawing.
Figure 1 represents, in front elevation, a pair of rolls constructed according
to my Invention; and Figure 2 represents a portion of the same on a larger
scale. The upper roll a is furnished with grooves b, c, d, of a nearly semi-
circular section, and the lower roll e is furnished with similar grooves, marked
respectively b, c, d'. When the grooves in the upper roll a and lower roll e
are opposed to each other, as represented in Figure 1, they present openings
f, g, h, between them, which said openings have a nearly circular figure. The
grooves on the rolls are not of a truly semicircular section, the said grooves
being of somewhat less depth than that of a semicircle, so that the openings
f, g, h, formed by the opposed grooves in the rolls a, e, are of greater diameter
horizontally than they are vertically. The figure of the grooves will be best
understood by reference to Figure 2, which represents on a large scale pro-
tions of the upper roll a and lower roll e. The dotted line i represents a true
circle struck from the centre k; the continuous lines l, m, which represent the
section of the grooves in the rolls, are struck from the centres n, o, excepting
the portions at ', m', which are struck from the centre k. The sectional
figure l, m, formed by the opposed grooves in the rolls a, e, is very nearly an
ellipse whose longer axis is situated horizontally, and the said figure l, m, may
either be produced by the method described, or may be made of the figure of
a true ellipse having the foci n, o.
I do not, however, confine myself to any particular figure in the grooves of
the rolls, so long as the opening formed between the rolls is nearly circular,
and of longer diameter in a direction parallel to the axes of the rolls than in
a transverse direction.
In Figure 1 the dotted lines around the openings f, g, h, represent true
circles, and show the said openings to be of less diameter vertically than hori-
zontally. I introduce a mandril into the hollow cylinder to be made into a
tube, and pass the said cylinder and mandril in succesion through the openings

page_text: f, g, h, in the rolls, Figure 1, each of the said openings through which the
cylinder is passed being of less size than that through which it was previously
passed. After the cylinder and mandril have been passed through any one of
the openings f, g, h, I sometimes cause the said cylinder and mandril to per-
form a quarter revolution on their axis, and again pass them between the rolls
through the same opening. Those portions of the hollow cylinder which in
the first rolling were acted upon by that portion of the opening of greatest
diameter will in the second rolling be acted upon by that portion of the
opening of least diameter, and the reverse.
By the two rollings described, every part of the hollow cylinder or tube is
equally or nearly equally acted upon. The cylinder or tube is passed in a
similar manner through grooves of progressively diminishing size, until the
said cylinder has been converted into a tube of the required dimensions. The
hollow cylinder to be converted into a tube may be operated upon either in a
hot or cold state. The mandril may be removed from tubes made according
to my Invention without difficulty. I sometimes finish the tubes by passing
them finally between rolls, having grooves of a truly semi-cylindrical figure.
This treatment has for its object the correction of the slightly elliptical figure
which the tube may have, and not the elongation or drawing of the tube.
Having now described the nature of my said Invention, and the manner of
carrying the same into practical effect, I wish it to be understood that I do
not limit myself to the precise details, as the same may be varied without
departing from the nature of my said Invention; but I claim as.my Invention
the improvement or improvements in the manufacture of tubes of copper or
alloys of copper, herein described, and illustrated in the accompanying Draw-s
ing; that is to say, forming the said tubes by passing hollow cylinders between
rolls, which said rolls are furnished with grooves of a nearly semicircular section,
the said grooves being somewhat less deep than they would be if their section
were truly semicircular.
In witness whereof, I, the said John Wilkes, have hereunto set my hand
and seal, this Twenty-third day of May, in the year of our Lord One
thousand eight hundred and fifty-six.
Witness,
GILBERT WILKES.
JOHN WILKES. (L.S.)