Improvements in and relating to the Manufacture of Tubular Structures.
Year: 1893

page_text: Date of Application, 2nd May, 1893-Accepted, 10th June, 1893
COMPLETE SPECIFICATION.
Improvements in and relating to the Manufacture of Tubular
Structures.
We, JOHN HAMILTON BROWN, HARVEY MAY MUNSELL, and ALONZO
WILLIAM PORTER, of Temple Court, New York, in the County and State of
New York, United States of America, Manufacturers, 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:-
The
The invention relates to tubular structures and the art of making them.
term "tubular structures" is intended to embrace tapered forms, such for example
as gun barrels, and also true cylindrical forms, such for example as pump and
engine cylinders, hollow shafts and the like.
For the purpose of explaining the invention, a tapered form suitable for a gun
barrel and a true cylindrical form suitable for a pump or engine cylinder have been
selected.
In the accompanying drawings,
Figure 1 is a view of a gun barrel in longitudinal section.
Figure 2 is a similar view of a true cylinder,
Figure 3 is a cross section on line, of Figure 1, and
Figure 4 is an enlarged view in side elevation of a portion of Figure 1, showing
the manner in which the end of the wire is anchored.
The gist of the invention lies in a tubular core made up of longitudinal segments.
and a body of wire wound under tension and surrounding the assembled segments of
the tubular core. The invention further contemplates the anchoring of the end of
the wire between the previous coil and an abutment by forcing into the gradually
contracting space and thereby severing from it a gradually thickening shaving so
as to fit the anchored end to the space and, when the form is taper, and greater
strength required at one end, as in a gun barrel, in providing the exterior of the
core with seats having the taper of the completed structure, and arranging the
layers of wound wire so that a longer shall extend continuously over a shorter layer
and over the seat adjacent thereto.
The segments which make up the core are represented by A. The number used.
is a matter of choice. The number chosen for illustration is twelve. In a true
cylinder the segments would have the same depth throughout their entire length,
but in a tapered structure, where greater strength is required at or near one end, it
is desirable that the segments have a gradually increasing or decreasing depth, as
shown in Figure 1.
The several seats on which the shorter layers of wire are wound are denoted
by B, B B B B and the layers of wire on said seats are denoted by C, C',
C, CC respectively, each consecutive exterior course extending over an interior
course and over the seat adjacent thereto. The several abutments at the ends of
the seats are denoted by b, b' b and 63.
When a course of wire finally reaches the full length its end is anchored against
an abutment provided therefor on the side of an end nut D.
As the wire is wound under tension up to an abutment, as shown in Figure 4, it
may be first forced bodily into the gradually contracting space E by a stroke upon
the strained strand e and, as the shaving e' is gradually sheared off, the tension may
be diminished to prevent breaking.
The winding of the courses of wire on the true cylindrical core, shown in
Figure 2, is quite similar to that of the full length courses on the tapered form,
shown in Figure 1.
The above described structure is of special utility wherever great strength is

page_text: required to resist internal pressure as it admits of subjecting each one of the several
core segments to special treatment, such for example as cold rolling or other
tempering, to set up therein a condition of special elasticity, and this treatment is in
fact resorted to in carrying this invention into practical effect.
The segments, made of such dimensions as to be readily cast of steel without
flaws and of homogeneous structure and subsequently treated, when desired, to raise
their elastic limit and tensile strength, are in a condition to withstand an enormous
hugging pressure from the surrounding wire.
The wire may be of a high grade, in practice a wire seven-hundredths of an inch
in diameter having a sustaining power of about fourteen-hundred pounds, so that
by varying the number of layers, wound under a given tension, or varying the
tension, with a given number of layers, the tubular structure may be made to with-
stand a very high pressure. By actual test, a tube of twelve segments, about four
inches deep, and wound with twenty-eight layers of wire of the above description
under a tension of six-hundred pounds, has withstood a bursting pressure of upwards
of sixty-thousand pounds to the square inch without any appreciable separation of
the segments. In practice the hugging pressure, or initial tension is made greater
than the bursting strain to which the tubular structure is to be submitted.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is :-
1. The tubular structure comprising a core formed of longitudinal segments
having a condition of special elasticity and a surrounding body of wire wound under
tension sufficiently great to withstand the bursting strain within the tube.
2. The tubular structure, comprising a core formed of longitudinal segments, and
a surrounding body of wire wound under tension in several layers, the end of a
layer being forced into the contracting space between the last coil and an abutment
to secure it.
3. The tubular structure, comprising a core formed of longitudinal segments
having seats on their exterior surface corresponding to the taper of the wound wire
body, and a body of wire wound under tension in several layers, a succeeding
exterior layer of the wound wire, extending continuously over a preceding inner
layer and over the seat adjacent thereto.
4. In making tubular structures, first forming the core of the tube in longitudinal
segments, aud subsequently setting up in each of the core segments a condition of
special elasticity by cold rolling or other suitable means for tempering.
5. In making tubular structures, first forming the core of the tube in longitudinal
segments, then setting up in each of the core segments a condition of special
elasticity by suitable tempering, and subsequently assembling the core segments and
submitting the assembled segments or core to an initial tension sufficiently great to
withstand the bursting strain within the tube, by jacketing.
Dated this 2nd day of May 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.