IMPROVEMENTS IN THE MANUFACTURE OF UNWELDED OR OPEN JOINTED STEEL AND IRON TUBES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by William Brown and David Brown and
William Weaver Vaughan, at the Office of the Commissioners of Patents on the
18th February 1876.
WILLIAM BROWN, and DAVID BROWN, and WILLIAM WEAVER VAUGHAN, all of
Smethwick, in the County of Stafford, Iron and Coal Masters. "IMPROVEMENTS
IN THE MANUFACTURE OF UNWELDED OR OPEN JOINTED STEEL AND IRON TUBES."
In the ordinary method of manufacturing unwelded or open jointed steel and
iron tubes, the pile, bloom, or billet of steel or iron from which the tube is to be
made is first rolled into a flat strip; flat strips thus made are heated and bent into
the required form, the process of manufacture consisting of two distinct processes,
namely, the production of a flat strip and the bending of the said strip into a
tubular form, whether the bending follows immediately upon the rolling of the strip
or is effected later.
In manufacturing the said unwelded or open jointed tubes according to our
Invention we roll a tube direct from the pile, bloom, or billet at one heat.
In operating upon the pile, bloom, or billet we commence to give it a trough
shape, preferably, by the first or second groove through which it is passed, and in
the subsequent rollings the said trough-shape is further perfected, the metal at the
same time being reduced in thickness and elongated. After the trough-shaped bar
has been brought to the thickness and breadth required for forming the tube, it is
passed through a groove having an elliptical section, the longer axis of the ellipse
being situated horizontally. The trough-shaped bar is passed through this groove
in a horizontal position, that is, one side of the trough is presented to that part of
the elliptical groove which is situated in the upper roll, and the other side of the
trough is presented to that part of the groove which is situated in the lower roll,
the horizontal plane in which the rollers are in contact dividing the trough-shaped
bar symmetrically.
In order to make the trough-shaped bar take the elliptical figure of the groove in
the rolls, an elliptical mandril may be supported between the rolls. This elliptical
mandril supports the interior of the partially made tube, and together with the
groove in the rolls gives a well formed elliptical figure to the tube. The edges of
the partially formed tube are after this treatment a considerable distance apart.
The partially formed tube is finally passed through a groove of a circular figure in
cross section; the partially formed tube is passed through this groove with its

page_text: longer diameter in a vertical plane. The elliptical figure of the tube is by this
treatment converted into a circular figure and a cylindrical tube with an open joint,
that is, an unwelded but close joint is produced, the two edges being in close
contact, but not united.
Instead of using one pair of rolls for bending the elliptical formed tube into a
circular figure, two or more pairs of horizontal rolls may be employed for that
purpose.
The interior of the tube may be supported by a cylindrical mandril during this
rolling.
By our Invention open jointed tubes of excellent quality are very economically
produced. The metal is not exposed to the strain and danger of cracking to which
it is exposed when it is first rolled into a flat strip and afterwards bent into a tube,
and as the number of rollings does not exceed or exceeds but little that required to
make a flat strip we produce the said open jointed tubes at the same cost as open
jointed tubes made from flat strips.
Tubes of a square elliptical or other figure in cross section may be made by our
method, and they may be plain or fluted externally.