IMPROVEMENTS IN THE MANUFACTURE OF TUBULAR OR HOLLOW FORMS OF IRON AND STEEL
Year: 1878

page_text: LETTERS PATENT to Jacob Geoghegan Willans, of 9, St. Stephen's Crescent,
Bayswater, in the County of Middlesex, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF TUBULAR OR HOLLOW FORMS OF IRON AND
STEEL."
Sealed the 21st January 1879, and dated the 24th July 1878.
PROVISIONAL SPECIFICATION left by the said Jacob Geoghegan Willans at
the Office of the Commissioners of Patents on the 24th July 1878.
JACOB GEOGHEGAN WILLANS, of 9, St. Stephen's Crescent, Bayswater, in the
County of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF TUBULAR AND
HOLLOW FORMS OF IRON OR STEEL."
My Invention relates to that part of the manufacture of tubular or hollow forms
of iron or steel, in which they are elongated or compressed into another size or
shape by rolling, drawing, hammering, or by pressure, and is particularly applicable
to those forms from which gun barrels and weldless tubes are made.
Hitherto it has been generally necessary in this process of elongation to have a
bar or mandrill in the interior, over which the iron or steel be drawn in order to
prevent the collapse of the tube, the use of bars or mandrills being troublesome, and
in some case impracticable or difficult.
My Invention is to have the interior of the iron or steel to contain either a friable
or an easily melted material, which will be elongated along with it, and which may
be removed when the iron or steel be drawn therewith to the desired extent, thus
leaving the tubular or hollow space free from collapse.
The friable materials employed are preferably in a finely divided state, and of a
refractory character, such as lime, powder, coke dust, ground burnt fire-clay, and
other powders, which will not cohere strongly at the heat employed, and which may
be removed by boring out or by means of water.
The easily melted materials employed are preferably those which will not injure
the iron or steel, and are sufficiently fusible to be run off from the heated tubular or
hollow forms when no longer required.

page_text: Some metals, such as zinc or its alloys, or fusible compounds of earths and alkali,
such as glass, may be used for the interior substance, and will run out when the
tube opened at the ends is heated in a vertical or inclined position for the
purpose.
I prefer to proceed as follows:-I pack inside the tubular or hollow iron or steel
a friable material, such as coke dust, and I close the open end or ends under the
hammer or with steel, so that the material will be securely confined without access
of air. I subsequently elongate them together by rolling at a suitable red heat to
about nearly the finished length required. I then remove the interior substance,
and finish by cold drawing in the usual manner.
When elongating those tubular or hollow forms that do not require to be highly
finished or to be of uniform substance, I complete them at a red heat by rolling,
hammering, or pressure, without any cold drawing.
When compressing tubular or hollow forms of iron or steel into other shapes, I
prefer to have a friable material, such as a mixture of coke dust and ground burnt
clay enclosed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Jacob Geoghegan Willans in the Great Seal Patent Office on the 24th
January 1879.
"
JACOB GEAGHEGAN WILLANS, of No. 9, St. Stephen's Crescent, Bayswater, in the
County of Middlesex. IMPROVEMENTS IN THE MANUFACTURE OF TUBULAR OR
HOLLOW FORMS OF IRON AND STEEL."
My Invention relates to that part of the manufacture of tubular or hollow forms
of iron or steel, in which they are elongated by rolling, drawing, hammering, or by
pressure, and is particulary applicable to those forms from which gun barrels and
weldless tubes are made.
Hitherto it has been generally necessary in this process of elongation to have a
bar or mandril in the interior, in order to prevent the collapse of the tube, the use
of bars or mandrils being troublesome, and in some cases difficult or impracticable.
My Invention is that the interior of the tubular or bollow iron or steel shall
contain a friable or an easily melted substance, which will be elongated with it, and
which may (if desired) be afterwards removed by means of water, or by drilling or
melting it out; after that the elongation be produced to the desired extent.
I use the following substances for the interior packing, viz. :-Finely crushed
well-burnt lime, of a sufficiently pure character as to slake afterwards, on contact
with water, the powder of coke, non-bituminous coal, charcoal, or other substance,
which does not cohere strongly at a red heat.
I also use one or more of these or other carbonaceous substances in a finely
divided state, intimately mixed with lime or other earth, preferring that all be as
free from water or other volatile matter as practicable.
Instead of the above I sometimes use a metallic substance, which during the
elongation will be soft or friable, and which will melt at a lower temperature than
steel, such as the grey cast iron used in foundries; or should the packing be required
to remain in the tube, I prefer to use ground burnt fire-clay for the purpose.
In carrying out my Invention I prefer to treat tubular or hollow castings of iron
or steel cast in the manner described in Patent No. 3425, dated Eleventh September,
One thousand eight hundred and seventy-seven, granted to me and to William
Henry Willans, but the Invention is also applicable to castings made in other ways.
I pack them tightly whilst hot with, by preference, a mixture of lime and coke
dust, in the proportion of one and one half measures lime to 1 measure coke, and
both ground to pass through a sieve of one-tenth inch mesh.
When fitted to within three-fourths inch of the upper end I place a damp mixture
of equal parts clay and sand, flattening it to about one-eighth inch in thickness, so
as to cover the friable packing.
After its moisture is evaporated I pour thereon some fluid steel to fill up the
casting, in order to confine the packing and prevent access of air during the subse-
quent heating.
When employing a metallic substance for the interior I prefer to pour it in
whilst molten, and when it be sufficiently cooled I pour thereon the fluid steel.
The tubular or hollow forms, with their interior packing, are afterwards heated
and passed under rolls or hammers in the manner customary in elongating steel
ingots into bars.
When cold the solid ends are cut off, and the tubular iron or steel is placed in a
vertical or inclined position for removal of the interior packing. This, in the case
of lime or of lime and carbonaceous matter, I effect by a jet of water injected from
underneath on to the packing, or the latter may be bored out.
In case of the interior packing being cast iron or other easily melted metallic
substance, the tubular or iron or steel is placed in an inclined position in a rever-
beratory furnace, and the interior melted out.

page_text: In most cases, after the tube be drawn along with its interior contents to about
the extent desired, I remove the interior and complete the drawing over a mandril
in the manner usually practised in the manufacture of iron and steel tubes.
Having thus described the nature of my Invention, and the manner of performing
the same, I would have it understood that I do not confine myself to the exact
details described, but what I claim in the manufacture of tubular forms of iron or
steel is,―
First. The elongating them along with interior contents, such as described.
Secondly. The removal of the interior substance after its elongation, by means
of water or by heat.
Thirdly. The first elongating them together with an interior substance, and after
removal of the latter the drawing of the tube over a mandril.
In witness whereof, I, the said Jacob Geaghegan Willans, have hereunto set
my hand and seal, this Twenty-fourth day of January, in the year of our
Lord One thousand eight hundred and seventy-nine.
J. G. WILLANS. (L.S.)