Improvements in the Manufacture of Tubes and in Apparatus therefor.
Year: 1887

page_text: Date of Application, 11th Oct., 1887
Specification Accepted, 29th Nov.. 1887
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Tubes and in Apparatus
therefor.
D
I, CHARLES WHILE of 6 Princes Terrace, Darlington Steel and Iron Works
Manager, 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 :—
Though this invention is not confined to the manufacture of metal tubes it is
doubtless to these that it will be chiefly applied and I will therefore describe it as
applied to the manufacture of metal tubes.
The invention will be most readily understood by reference to the accompanying
drawings in which fig. 1 is a side elevation of the apparatus, Fig. 2 a like view
in longitudinal section, Fig. 3 a cross section upon line e, f of figures 1 and 2,
and Fig. 4 a view of the mandrel and cylinder or blank out of which the tube is
made.
a are a number of conical rolls preferably three disposed around the tapered
mandrel 6 to the axis of which they are set obliquely as shown in figure 1, so as to
impart a forward movement to the tube in the direction of the arrow. c is the blank
from which the tube is to be made; it is in the form of a short cylinder perforated
disc or ring and is placed upon the mandrel b somewhat as shown in figure 4. The
mandrel is secured against longitudinal movement but is free to rotate, and is
provided with a sleeve i capable of longitudinal movement for the purpose of pushing
forward the blank until it is seized by the rolls which may be driven by bevel gearing
as shown in the drawings or in any other convenient manner.
The operation is as follows:-
The sleeve is withdrawn and a blank c placed on the back end of the mandrel and
driven forward to the rolls a by the sleeve i. The rolls which all revolve in the same
direction gradually compress and reduce the blank forcing it along the tapered end of
the mandrel and drawing it out till it leaves the mandrel by the smaller or pointed
end 6 and extends in the form of a tube d travelling from the mill in the direction of
the arrow. In the drawing figure 2, the tapered end of the mandrel is shown as not
extending to the point where the tube leaves the rolls; this is immaterial as I find it

page_text: quite practicable to reduce both the internal and external diameter of the tube after it
has left the mandrel, and in the case of very small tubes it would be hardly possible
to extend the mandrel the full distance because the point would be so fine as to run
serious risk of being broken bent or twisted off. The rolls, mandrel &c. are carried
in any suitable framework and instead of applying the blank to the back end of the
mandrel the mandrel may be withdrawn and the blank applied over the pointed end;
this would entail temporary longitudinal movement of the mandrel which would
however be prevented during the rolling of the blank.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a tube rolling mill the method of rolling a tube so that it leaves the mandrel
at its smaller or pointed end substantially as described and illustrated in the
accompanying drawings.
2. In a tube rolling mill the combination with a tapered mandrel such as b of
one or more tapered rolls such as a so revolved and set towards the axis of the
mandrel as to cause the tube when formed to leave the mandrel at its smaller or
pointed end the whole substantially as described and illustrated in the accompanying
drawings.
3. In a tube rolling mill the combination of three or other number of obliquely
mounted rolls converging towards their smaller ends and producing a motion of the
tube in that direction, with a central mandrel tapering in the same direction as the
rolls and maintaining its position longitudinally during the operation of rolling the tube
the whole constructed and operating substantially in the manner and for the purpose
described and illustrated in the accompanying drawings.
Dated this Sixth day of October 1887.