Improvements in Making Solid-drawn Metal Tubes.
Year: 1897

page_text: Date of Application, 9th Dec., 1897
Complete Specification Left, 8th Sept., 1898-Accepted, 22nd Oct., 1898
We, JOHN TANNAHILL and ANDREW EADIE, both of the Clydesdale Tube Works,
Rutherglen, in the County of Lanark, North Britain, Engineers, do hereby
declare the nature of this invention to be as follows, that is to say:-
The said invention has for its object to apply improved and simple machinery
to the part of the processes for making solid-drawn metal tubes which consists in
piercing and forming into a short thick tube, to be subsequently lengthened, a
solid cylindrical billet.
In the improved machinery the billet is made to pass between a pair of rollers
carried, with their axes parallel, in massive housings. The rollers have formed
on their surfaces screw threads of relatively small pitch and small projection;
and are adjusted at such distance apart that the billet is firmly held by them
when passing between them. The billet which is supported by a comparatively
small free roller or a bar below, is parallel to the large rollers, and these causo
it to rotate rapidly whilst it is forced on end by the screw action. A mandril
with a pointed end is fixed so that the billet in being moved forwards is forced
against it, and becomes pierced by the mandril.
Dated this Eighth day of December 1897.
EDMUND HUNT,
Applicants' Agent.
Improvements in Making Solid-drawn Metal Tubes.
We, JOHN TANNAHILL and ANDREW EADIE, both of the Clydesdale Tube Works,
Rutherglen, in the County of Lanark, North Britain, Engineers, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following state-
ment, that is to Bay :-
The said invention has for its object to apply improved and simple machinery
to the part of the processes for making solid-drawn metal tubes which consists in
piercing and forming into a short thick tube, to be subsequently lengthened, a
solid cylindrical billet.
In the improved machinery the billet at about a red heat is made to pass
between a pair of rollers carried, with their axes parallel to each other and to
the billet, in massive housings. The rollers have formed on their surfaces screw
or helical threads or projections of relatively small pitch and small projection;
Price T

page_text: and are adjusted at such distance apart that the billet is firmly held by them
when passing between them. The rollers cause the billet to rotate rapidly whilst
it is forced on end by the screw action. A mandril with a pointed end is fixed
so that the billet in being moved forwards is forced against it and becomes
pierced by the mandril.
And in order that the said invention and the manner of performing the same
may be properly understood we hereunto append two sheets of explanatory draw-
ings to be hereinafter referred to and representing an example of machinery made
according to the invention.
Figure, 1, on Sheet, 1, of the drawings is a sectional elevation of the machine;
and Figure, 2, on Sheet, 2, is a sectional plan. In these drawings the same re-
ference letters are used to mark the same or like parts wherever they are repeated.
The operating rollers, A, are carried in massive housings, B, their end jour-
nals, A1, being held in bearings,. C, resting on horizontal guides, B1, formed in
the housings, these bearings being adjustable 'towards or from each other by
screw spindles, 1), acted on by internally screwed tubes, E, which can be turned
by means of spur gearing, 1, at both sides of the machine (although shown only
at one side) a shaft, F1, of the gearing extending across from one side to the
other of the machine. The rollers, A, are driven by spur gearing, G, indicated
by dotted circles in Figure, 1, from a first motion shaft, G 1, driven in any con-
venient way.
The billet, H, is entered from the front of the machine shown in Figure, 1, and
at the lower part of Figure, 2, over a guide plate, J; and passing between the
rollers, A, in a line in the plane of their axes, is by them made to rotate rapidly
whilst it is forced towards the back of the machine by the action of the screw or
helical threads or projections on the rollers. The billet, II, is by the action
referred to forced against the pointed end of a mandril, K, which is rigidly held
by a bracket or standard, L, to which its further end is fixed. As the billet
passes between the rollers, A, it is supported by an antifriction roller, M, indicated
partly by dotted lines.
The screw or helical threads or projections of the rollers, A, as shown in
Figure, 1, are of a rounded shallow form, but the form and the proportions as
to pitch and depth may be varied in different cases.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that what
we claim is;-
-
In the manufacture of solid-drawn metal tubes passing a billet longitudinally
between a pair of rollers the surfaces of which are formed with screw or helical
threads or projections and which make the billet rotate and at the same time
force it against a pointed stationary mandril, substantially as hereinbefore
described.
Dated this Seventh day' of September 1898
EDMUND HUNT,
Applicants' Agent.