Year: 1887

page_text: Date of Application, 18th May, 1887
Complete Left, 21st Jan., 1888
Complete Accepted, 24th Feb., 1888
Action of Frost.
poposed w CHU
I, JOHN WARWICK of No. 108 Rye Hill in the City and County of Newcastle-
upon-Tyne, Lead Manufacturer, do hereby declare the nature of my invention to
be as follows:-
My invention consists in improvements in the construction of water pipes exposed
to the action of frost and which apply mainly to lead water pipes for dwelling houses.
It is well understood that a pipe made circular in section gives the largest possible
area of contents in relation to its circumference of any figure and therefore water
freezing in a circular pipe must either (by the effect of expansion produced) stretch
the material of which the pipe is formed or burst the pipe. To obviate this
inconvenience the method is occasionally adopted of slightly Hattening the pipe so as
to make it oval in section and thus to give room for expansion, and in proportion to
the degree to which the pipe is flattened and preserved uniform in section this process
is efficacious to prevent bursting. The arrangement is however disadvantageous in
important respects. An oval pipe bends more easily in one direction than in the
other, and each bend of an oval pipe tends to make it more oval and diminish its
area and efficacy to convey water, or to make it more round and diminish its
efficacy against the action of frost according as it is bent in one direction or
the other.
Now I by my invention construct the pipe with a series of corrugations running
the length way of the pipe each one of which by adequate pressure from the
inside is capable of yielding increased circumference to the pipe and giving room for
expansion.
The corrugations may be of any convenient form and depth, or the purpose I have
CD071

page_text: in view might be obtained by making the section of the pipe hexagon for instance
like a cell of a honey comb but not so effectually as by corrugation.
The thickness of the material of the pipe may be also made uniform at all parts of
the corrugation, but I prefer to vary the material in the corrugations as to give the
best distribution of strength to resist distortion. I then form a pipe giving a large
scope for expansion and capable of enduring many freezings of its contents before
coming to a circular form or bursting, and yet one which bends with equal ease in
any direction with even less tendency than an ordinary pipe to close in bending or to
lose its shape.
I form the pipe of load, or composition in the ordinary way in which lead pipes are
formed varying only the die and mandril so as to give the required section.
Dated this Seventeenth day of May 1887.
JAMESON & SCHAEFFER,
Agents for Applicant.

page_text: COMPLETE SPECIFICATION.
0
Improvements in the Construction of Water Pipes Exposed to the
Action of Frost.
I, JOHN WARWICK of No. 108 Rye Hill, in the City and County of Newcastle-
upon-Tyne, Lead 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 :-
My invention consists in improvements in the construction of water pipes exposed
to the action of frost, and which apply mainly to lead water pipes for dwelling houses.
It is well understood that a pipe made circular in section gives the largest possible
area of contents in relation to its circumference of any figure and therefore water
freezing in circular pipe must either (by the effect of expansion produced) stretch
the material of which the pipe is formed or burst the pipe. To obviate this
inconvenience the method is occasionally adopted of slightly flattening the pipe so
as to make it oval in section and thus to give room for expansion and in proportion
to the degree to which the pipe is flattened and preserved uniform in section this
process is efficacious to prevent bursting. The arrangement is however disad-
vantageous in important respects. An oval pipe bends more easily in one direction
than in the other, and each bend of an oval pipe tends to make it more oval and
diminish its area and efficacy to convey water or to make it more round and diminish
its efficacy against the action of frost according as it is bent in one direction or the
other. Now I by my invention construct the pipe with a series of corrugations
running the length way of the pipe each one of which by adequate pressure from the
inside is capable of yielding increased circumference to the pipe and giving room for
expansion. The corrugations may be of any convenient form and depth, or the
purpose I have in view might be obtained by making the section of the pipe
hexagon for instance like a cell of a honey comb but not so effectually as by
corrugation.
The thickness of the material of the pipe may be also made uniform at all parts-
of the corrugation but I prefer to vary the material in the corrugations as to give
the best distribution of strength to resist distortion. I then form a pipe giving a
large scope for expansion and capable of enduring many freezings of its contents
before coming to a circular form or bursting and yet one which bends with equal
ease in any direction with even less tendency than an ordinary pipe to close in
bending or to lose its shape. I form the pipe of lead or composition in the ordinary
way in which lead pipes are formed varying only the die and mandril so as to give
the required section.
In further illustration of the principle involved in my invention reference is made
to the drawings hereto attached wherein the sections of pipe marked A Figs. 1. and 2.
are sections according to my invention, and wherein in Fig. 1 I have shewn 2 lines,
B the inside periphery of a circular pipe, and C, inside periphery of the pipe shewn

page_text: in Fig. 1 thus indicating graphically the difference between the periphery of my pipe
and that of a circular pipe of equal area which difference constitutes the security
against rupture by freezing that is to say the material of the pipe shewn in section
in Fig. 1 may without actual stretching of the internal periphery and only by change
of shape be so modified as to allow of enlargement to the extent of the difference
of the lines shewn. I find however in practice that a very small amount of stretching
is possible without fracture and that with the enlargement due to change of shape
and probably as a consequent incident in that change there is a slight stretching
action which very much enlarges the limit of safety in pipes made according to my
invention.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed I declare that what I
claim is
The construction of lead or composition pipes for the conveyance of water of such
sections as to be easily bent without a tendency to collapse or become inefficient and
yet to allow of enlargement of area without expansion of the material of the pipe
substantially as described.