IMPROVEMENTS IN THE MANU- FACTURE OF COPPER TUBES "
Year: 1882

page_text: LETTERS PATENT to Samuel Walker of Birmingham in the county of
Warwick Manufacturer for an invention of "IMPROVEMENTS IN THE MANU-
FACTURE OF COPPER TUBES "
PROVISIONAL SPECIFICATION left by the said Samuel Walker at the
Office of the Commissioners of Patents. on the 31st March 1882.
SAMUEL WALKER of Birmingham in the County of Warwick Manufacturer
"IMPROVEMENTS IN THE MANUFACTURE OF COPPER TUBES"
According to one of my improvements, I manufacture copper tubes by taking
thick circular discs of copper heated to redness and by means of raising forcing or
drawing through dies, I give to the said heated disc of copper a cup like figure;
that is the figure of a hollow cylinder closed at one end. This forming of the disc
of heated copper into a hollow cylinder may be performed at one or more operations
according to the size and strength of the discs of. copper operated upon. I prefer
to operate the moveable die of the raising forcing or drawing through dies by
hydraulic power but I do not limit myself thereto as other motive power may be
employed. The hollow cylinders closed at one end thus formed may be converted
into tubes of the required length and diameter by cutting off the closed end and
elongating them and reducing their diameter by rolling and drawing. Or instead
of cutting off the closed end, the said end may be pierced in its centre and the
metal forming the said end expanded into a tubular form before the hollow cylinder
is rolled and drawn into a tube. Although I prefer to make the copper discs red
hot before operating upon them with the raising forcing or drawing through dies,
yet the said discs may be oporated upon cold. In this case they require to be
annealed after cach operation.
According to another of my improvements, I make the cast hollow ingots of
copper from which copper tubes are made by rolling and drawing preferably of an
oblong figure in cross section instead of making them of a cylindrical figure as
usual. For this purpose I employ an oblong mould and in the middle of the mould
I support a core consisting of a flat or nearly flat plate of iron or a flat plate of such
non inetallic material as is used for making cores for casting.
The core is of such breadth relative to the longer diameter of the mould that
the hollow ingot produced is of less thickness at its short than at its longer sides.
By the processes of rolling and drawing the ingot is brought into a cylindrical form
and elongated and reduced in diameter.

page_text: -
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Samuel Walker in the Great Seal Patent Office on the
19th September 1882.
SAMUEL WALKER of Birmingham in the County of Warwick Manufacturer
"IMPROVEMENTS IN THE MANUFACTURE OF COPPER TUBES."
According to my improvements I manufacture copper tubes by taking circular
discs of copper, either cold or heated, and by forcing the same by means of a
plunger or mandril through raising, forcing or drawing through dies, I give to the
said dises of copper, a cup like figure; that is, the figure of a hollow cylinder closed
at one end. This forming of the disc of copper into a hollow cylinder may be
performed at one or several operations according to the size and strength of the
discs of copper operated upon.
I prefer to operate the die or the plug or mandril by hydraulic power but I do
not limit myself thereto as other motive power may be employed.
The hollow cylinders closed at one end and thus formed may be converted into
tubes of the required length and diameter by cutting off the closed end and
elongating them and reducing their diameter by rolling and drawing. Or instead
of cutting off the closed end the said end may be pierced in its centre and the metal
forming the said end expanded into a tubular form before the hollow cylinder is
rolled and drawn into a tube.
In order more fully to explain my invention
I will describe the manufacture according to my invention of a copper tube of a
particular size.
In making a copper tube of about fifteen feet in length, of about three inches
external diameter and having a thickness of metal of about one eighth of an inch I
proceed as follows;--
I take a circular disc of copper of about two feet in diameter and five eighths of
an inch thick. By means of raising dies or tools of the ordinary kind, I operate
upon the said dise four or five times or as many times as are requisite so as to
give it the figure of a hollow cylinder closed at one end and about four inches in
diameter. I prefer to operate the moveable die, plug or mandril by hydraulic
power but I do not limit myself thereto. The bottom of the hollow cylinder is
cut away or pierced and the short tube thus made is brought to the required
length and thickness by rolling and drawing.
The metal may be annealed as required during the operation of the raising dics
or tools.
The copper disc may be operated upon either hot or cold.
The details of the process whereby the disc of copper is raised into a hollow
cylinder closed at one end are varied according to the size length and strength of
the copper tube to be made.
For example where a copper tube of small diameter and thin metal is required,
the copper disc employed is thin and the raising of the said disc into a hollow
cylinder closed at one end may be effected by one operation of the drawing
through dies. But the size of the disc as well as its thickness and the number of
times it is operated upon by the dies may be varied without materially affecting
the result.
Having now described the nature of my invention and the manner in which the
same is to be performed I wish it to be understood that. I claim as my invention
of "Improvements in the manufacture of copper tubes":-
Manufacturing copper tubes by raising a dise of copper. into a hollow cylinder
closed at one end by the operation of raising forcing or drawing through dies

page_text: worked preferably by hydraulic power, the end of the said hollow cylinder either
being cut off or pierced, the partially made tube thus obtained being completed by
the operation of rolling and drawing substantially as hereinbefore described.
In witness whereof I the said Samuel Walker have hereunto set my hand
and seal this Eighteenth day of September in the year of our Lord One
thousand eight hundred and eighty two.