AN IMPROVED METHOD OF AND MACHINERY FOR MAKING LEAD TRAPS
Year: 1875

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London,
for the Invention of " AN IMPROVED METHOD OF AND MACHINERY FOR
MAKING LEAD TRAPS."-A. communication from, abroad by Frederick
Nelson Du Bois, of the City and State of New York, United States
of America, Manufacturer.
Sealed the 20th December 1875, and dated the 20th October 1875.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition,
on the 20th October 1875.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "AN IMPROVED METHOD OF AND MACHINERY
FOR MAKING LEAD TRAPS," a communication, to be as follows:-
The nature of this Invention consists in making lead traps in their
finished state, substantially in the same general manner as that in which

page_text: lead pipe is made, by means of very strong cylinders for holding the
lead and powerful hydraulic pressure for forcing it out through an
orifice having the shape of the pipe required, but with this essential
difference that in making ordinary lead pipe the lead is supplied in
equal amount to all parts of the orifice at the same time, and the pipe
.comes out straight; while to make lead traps by this Invention the lead
is furnished in greater quantity, first on one side of the orifice and then
on the other, as it may be desired to make the pipe or trap bend either
way.
A steel cylinder, of which there must be one for each size of trap to
be made, is held in a fixed horizontal position by suitable fastenings, it
is then heated by any convenient means to about 400°. The ends are
now filled with melted lead which is allowed to cool until the heat is a
little below the melting point, when a plunger or ram attached to a
hydraulic water cylinder is brought against the lead in each end. Tho
force exerted by one, which will be from twenty thousand to thirty
thousand pounds per square inch on the surface of the lead, is counter-
balanced by the other, and drives the lead into and fills the two upward
passages to a circular orifice. These two streams of hot and soft but
not melted lead are kept separate from each other until they arrive near
the orifice by a steel core which has a nut on the bottom to prevent its
being forced upward, and a projection around the top which forms the
inside of the orifice; also by a partition. These partitions are a part of
the steel casting, and extend to and fit close against the core on its
opposite sides and complete the separation of the two streams of lead
until it is desired to unite them just below the orifice.
By the hydraulic machinery in common use in the manufacture of
lead pipe the two rams which fit closely in the ends of the said cylinder
and which force forward the lead are under easy control of the person
operating the machine.
The operation of forming a trap is to move forward the two streams
of lead with equal speed, supplying an equal amount of lead to all parts
of the orifice, when the lead will be forced out through it forming a
round smooth pipe that will be straight, the soft, hot, and clean lead of
of the two streams having united inseparably in the space between the
top of the partition and the orifice under a pressure varying with
different degrees of heat. The speed of the one stream is now reduced,

page_text: and the speed of the other stream increased; the effect is that one side
of the orifice is supplied with only enough lead to form the short side of
a curved pipe, while the other side of the orifice is supplied with enough
lead to form the long side of the curved pipe, and a little more than
half of the circumference, the lines of union between the two streams
of lead moving toward the side that supplies the least lead. Hence the
pipe is formed by a natural and easy distribution of the metal and is free
from waves or imperfections. The curve being thus formed the order of
speed of the two streams of lead is now reversed, when the same effect
takes place in the opposite direction, forming the pipe or trap, after
which the speed of both streams is again made equal.
The operation above described is repeated until the lead in the cylinder
is exhausted, when the rams are withdrawn and more lead introduced,
as at first.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 20th April 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twentieth day of October, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
ninth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Robert Lake, Her special licence
that I, the said William Robert Lake, my executors, administrators,
and assigns, or such others as I, the said William Robert Lake, my
any time agree
executors, administrators, and assigns, should at
with,
and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for
"AN IMPROVED METHOD OF AND MACHINERY FOR MAKING LEAD TRAPS," a com-
munication to me from abroad by Frederick Nelson Du Bois, of the

page_text: City and State of New York, United States of America, Manufacturer
upon the condition (amongst others) that I, the said William Robert
Lake, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the samo
to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in
and by the following statement, reference being had to the accompanying
Drawing forming a part of this Specification:---
The nature of this Invention consists in making lead traps in their
finished state, substantially in the same general manner as that in which
lead pipe is made by means of very strong cylinders for holding the lead,
and powerful hydraulic pressure for forcing it out through an orifice
having the shape of the pipe required, but with this essential difference,
that in making ordinary lead pipe the lead is supplied in equal amount
to all parts of the orifice at the same time, and the pipe comes out
straight, while to make lead traps according to this Invention the lead
is furnished in a greater quantity, first on one side of the orifice and
then on the other, as it may be desired, to make the pipe or trap bend
in either direction.
The said Invention comprises the process of making the traps as above a
specified, the seamless compressed trap resulting from the said process
and the novel combination of parts, whereby the perfect union of the
material operated upon in the formation of the trap is secured.
Figure 1 is an end elevation of an apparatus called the cylinder, and
which is a thick casting of steel of great strength; Figure 2 is a vertical
longitudinal section of the same; Figure 3 is a vertical transverse
section Figure 4 is an elevation; and Figure 5 is a horizontal section
of the said apparatus.

page_text: The method of operating in practising this Invention is as follows:-
The steel cylinder, of which there must be one for each size of trap to
be made, is held in a fixed horizontal position, as represented in the
Drawing, by suitable fastenings, it is then heated by any convenient
means to about 400° Fahrenheit. The ends A' and A" are now filled
with melted lead which is allowed to cool until the heat is a little below
the melting point, when a plunger or ram (not shown in the Drawing)
attached to a hydraulic water cylinder is brought against the lead in
each end of the apparatus. The force exerted by one ram which will be
from twenty thousand to thirty thousand pounds per square inch on the
surface of the lead is counterbalanced by the other, and drives the lead
into and fills the two upward passages to the circular orifice e and e¹.
These two streams of hot and soft but not melted lead are kept separate
from each other until they arrive near the orifice by the steel core B
which has a nut on the bottom to prevent its being forced upward, and
a projection around the top which forms the inside of the orifice; also
by the partition P (shown by the dotted lines in Figure 2, and the top
of which is shown at e", Figure 3). These two partitions are a part of
the steel casting, and extend to and fit close against the core on its
opposite sides and complete the separation of the two streams of lead
until it is desired to unite them just below the orifice. These partitions
are made zig-zag in their cross sections, as shown in Figure 5, in such
manner that the two streams of lead have their adjacent surfaces formed
with alternating projections or undulations so that when the two surfaces
are brought together they will be lagged into each other, a much greater
area of contact being by this means obtained, and a much more efficient
welding secured by the subsequent cold pressure than with many
materials would otherwise be secured.
By a suitable arrangement of the hydraulic machinery in common use
in the manufacture of lead pipe, the two rams which fit closely in the
ends of the said cylinder and which force forward the lead are under
easy control of the person operating the machinery.
In the operation of forming the trap, represented in Figure 6, the two
streams of lead are moved forward with equal speed and supply an equal
amount of lead to all parts of the orifice, when the lead will be forced
out through it, forming a round smooth pipe that will be straight, the
soft, hot, and clean lead of the two streams having united inseparably in
the space between the top of the partition, and the orifice under a

page_text: pressure varying with different degrees of heat from fourteen thousand
to eighteen thousand pounds per square inch. The part of the trap now
formed is represented from a to b, in Figure 6, and by the dotted lines
at the top of Figure 2, each stream having furnished lead for half of the
circumference of the pipe. The speed of the right-hand stream A" is
now reduced, and the speed of the left-hand stream increased, the effect
being that the side of the orifice at e¹ is supplied with only enough lead
to form the short side of a curved pipe, while the other side of the
orifice at e is supplied with enough lead to form the long side of the
curved pipe and a little more than half of the circumference, the lines
of union between the two streams of lead moving toward the side that
supplies the least lead. Hence the pipe is formed by a natural and easy
distribution of the metal, and is free from waves or imperfections. The
curve being thus formed from 6 to c the order of speed of the two
streams of lead is now reversed, when the same effect takes place in the
opposite direction, forming the pipe or trap from c to d, then the speed
of both streams is again made equal and a straight part is formed, as at
first, and the pipe when sawn off at the orifice is a finished lead trap
without a seam, and of equal thickness in all its parts.
The operation above described is repeated until the lead in the cylinder
is exhausted, when the rams are withdrawn and more lead introduced as
at first.
Although I have specified lead as the material of which the traps may
be made, yet any other soft metal may be employed. Furthermore, I
do not limit myself to the use of soft metal, inasmuch as clay and a
other plastic materials may be operated upon in the same manner to
produce traps that are seamless and compressed, the traps being of
course baked, burned, or hardened by subsequent treatment when the
same are made of plastic material, as just set forth.
Having thus fully described the said Invention, as communicated to
me by my foreign correspondent, and the manner of performing the same,
I wish it understood that I claim,―
First. The process of making traps by the ejectment of two or more
convergent streams of material moving with unequal velocities through
an annular orifice or die, as above set forth.
Second. The traps consisting of the seamless compressed pipe, made
as above set forth.

page_text: Third. The zig-zag partitions combined with the annular orifice or dic,
as above specified, and for the purpose set forth.
In witness whereof, I, the said William Robert Lake, have here-
unto set my hand and seal, this Twentieth day of April, in the
year of our Lord One thousand eight hundred and seventy-
six.
Witness,
ROWLAND G. BROWN,
8, Southampton Bdgs.,
London.
W. ROBT. LAKE. (L.S.)