Improvements relating to the Manufacture of Tubes.
Year: 1897

page_text: Improvements relating to the Manufacture of Tubes.
I, ALFRED CECIL WRIGHT, of the Firm of James Warne, of Watery Lane, in
the City of Birmingham, Manufacturers, do hereby declare the nature of this
invention to be as follows:-
This invention consists of improvements relating to the manufacture of tubes
and especially to the production of weldless steel tubes, my object being to facili-
tate the process of drawing or elongating the tube blanks to the required dimen-
sions.
In the ordinary process of drawing tubes or tube blanks, the surfaces of the
tube and that of the dies or other tools are freely lubricated with oil or grease or
like unctuous substances, and such drawing down process necessitates a great
expenditure of mechanical energy. After the tube has been drawn or reduced to
the required dimensions, it is necessary to thoroughly remove the whole of the
grease in the event of the tube surfaces requiring to be plated, or japanned, as
otherwise such operations cannot be efficiently performed.
In drawing tubes or tube blanks in accordance with my invention I prevent the
actual contact of the surfaces of the steel or other tube to be drawn, with the
surfaces of the dies or other tools, by an interposing film of soft metal, preferably
tin. The tin or other soft metal can be applied either by immersion of the tube
or tube blank in a bath of the molten metal before submitting it to the drawing
process or in any other convenient manner.
By thus employing an interposing film of tin or other soft metal between the
surfaces of the tube or blank and the dies and mandrels or operating tools or
appliances, I am enabled to dispense entirely with the use of oil, grease, or like
unctuous substances, and at the same time to very materially reduce the expendi-
ture of mechanical energy required for the drawing or reducing process.
The thin film of tin or other soft metal can be readily removed if necessary at
the conclusion of the drawing or reducing process.
Improvements relating to the Manufacture of Tubes.
I, ALFRED CECIL WRIGHT, trading as James Warne, of Watery Lane, in the
City of Birmingham, Manufacturer, 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; -
This invention consists of improvements relating to the manufacture of tubes
[Pin 1

page_text: or hollow rods and especially to the production of weldless tubes, my object being
to facilitate the process of drawing, reducing, or elongating the tube blanks to
the required dimensions. My invention is also applicable to the manufacture
of wire or solid rods which are drawn or elongated in the like manner as tubes or
hollow rods.
In the ordinary process of drawing tubes or tube blanks, the surfaces of the
tube and that of the dies or other tools are freely lubricated with oil or grease
or like unctuous substances, and such drawing down process necessitates a great
expenditure of mechanical energy. After the tube has been drawn or reduced
to the required dimensions, it is necessary to thoroughly remove the whole of
the grease in the event of the tube surfaces requiring to be plated, or japanned
as otherwise such operations cannot be efficiently performed.
In drawing tubes or tube blanks in accordance with my invention I prevent
the actual contact of the surfaces of the steel or other tube to be drawn, with the
surfaces of the dies or other tools, by an interposing film of soft metal or anti-
friction metal; such metal by gliding through the die along with the tube acts
as an efficient lubricant exactly in the place required and is not pushed off the
tube at the die mouth as with ordinary lubricants. The metal which I preferably
employ consists of a mixture of tin and lead in the proportion of 6 parts tin to
4 parts lead. Such a mixture in addition to being cheaper than pure tin, gives
a better coating upon the tube. The anti-friction metal can be applied either by
immersion of the tube or tube blank in a bath of the molten metal before sub-
mitting it to the drawing process or in other convenient manner.
By thus employing an interposing film of anti-friction metal between the sur-
faces of the tube or blank and the dies or mandrels or operating tools or appli-
ances, I am enabled to dispense entirely with the use of oil, grease, or like
unctuous substances, to effect a great saving in the wear of the dies and mandrels,
and to very materially reduce the expenditure of mechanical energy and the time
required for the drawing or reducing process. My treatment also permits of the
employment of a cheaper steel for the production of weldless steel tubes for cycles
and other constructional purposes, the tube produced therefrom being quite equal
in quality to the tubes produced in the ordinary manner from Swedish steel. I
am also enabled to draw tubes of hard white metal and other alloys, such as can-
not be otherwise drawn, and to facilitate the drawing of copper, brass, and the
like tubes.
In the drawing of weldless steel tubes I do not remove the tube from its man-
drel until it has been finished to the required size, passing it several times through
dies without annealing and pickling between the passes, but after each pass or
after the tube has been drawn through each die I subject it to the action of a
reeling or releasing machine to sufficiently release the tube to permit of the free
flow of the metal in the next draw or pass. Thus in the drawing of a tube whose
thickness on leaving the rolls is equal to about number eleven gauge down to
a thickness equal to number twenty gauge, I first coat the tube with anti-friction
metal (after annealing if necessary) and then draw it through a series of five
or six dies until reduced to the required finished size. After leaving each die
the tube is reeled but not taken off the mandrel before being passed through the
next.
My invention enables me to draw or reduce brazed tube which ordinarily can-
not be drawn through a die and hence cannot be made sufficiently stiff or rigid
to permit of its employment for several services to which it would otherwise be
applicable. Thus if a brazed tube is required to finish at one inch diameter I
take a tube one inch and one-eighth in diameter, and after coating it with anti-
friction metal I draw it, without a mandrel, through a suitable die, and thereby
reduce it to the required one inch diameter..
The anti-friction metal can be readily removed if necessary at the conclusion of
the drawing or reducing process.

page_text: Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what
I claim is:.
-
1. In the drawing of weldless or other tubes and the like, the interposition of
a film of anti-friction metal between the surfaces of the tubes or blanks and the
dies and mandrels or operating tools or appliances, substantially as and for the
purposes described.
2. The drawing of tubes through a series of dies until reduced to the required
finished size without intermediate annealing and pickling and without removal
from the mandrel, the tubes being reeled or released after passing through each
of the dies, substantially as and for the purpose described.
3. The improvements relating to the drawing of tubes coated with anti-friction
metal, substantially as described.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., &
13, Temple Street, Birmingham, Agents for the Applicant.