IMPROVEMENTS IN PIPE JOINTS FOR CONTAINING LIQUIDS, GASES, AND AIR, BUT MORE ESPECIALLY APPLICABLE TO GAS AND WATER MAINS
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Martin Benson at the Office of the
Commissioners of Patents on the 1st December 1877. A communication
from abroad by William Painter, of Baltimore, Maryland, United States of
North America.
MARTIN BENSON, of No 9, Southampton Buildings, London. "IMPROVEMENTS IN
PIPE JOINTS FOR CONTAINING LIQUIDS, GASES, AND AIR, BUT MORE ESPECIALLY
APPLICABLE TO GAS AND WATER MAINS." [A communication from abroad by
William Painter, of Baltimore, Maryland, United States of North America.]
This Invention is designed to furnish a means of rapidly and economically forming
a fluid-tight joint in pipes, and is especially adopted to gas and water mains ;
various devices for effecting this end are in use consisting essentially in means for
driving or calking a packing material into the pipe joint or connection, or forcibly
drawing the pipe section upon elastic or other gasket material. From its property
of resisting the action of corroding agents, lead is almost universally used as a
packing, and is most commonly applied to the joint by casting it in place and
subsequently calking it. The usual calked joint however, aside from being un-
certain and expensive, is open to the objection that the slightest deflection or
sagging of the pipes or mains causes leakage
By my Invention all the advantages of lead packing are secured, and at the same
time danger of leakage from sagging or other ordinary change of position in the
mains is obviated, these desirable ends are attained by casting a lead gasket within
a groove in the interior of the bell or socket of the pipe, and after the sections are
in place, forcing the gasket to its seat by means of fluid pressure as herein-after
described.
Fig. 1 is a longitudinal sectional view of the improved pipe joint; Fig. 2 is a
similar view shewing the gasket forced to its seat.
In the accompanying Drawings, A, A¹, represent the male and female sections of
the mains; an annular groove having tapered sides, as shewn, is cast in the interior
of the bell, and within the groove is cast a lead gasket a; a threaded opening b
Dmine B1

page_text: communicates with it. The intorior diameter of the bell or socket is enlarged at
either side of the annular groove, as shewn, to admit of the sections of pipes being
jointed at a considerable angle with each other, without requiring the bell to be
much larger at the groove than the male section of the pipe
In case of diflection after the mains are laid the gasket thus becomes as it were
a fulcrum, and the degree of change of form to which it is subjected is reduced to
a minimum, this construction is not really essential. The bell is made somewhat
less in depth than that required in the ordinary or socket calked joint.
The process of forming my joint is as follows -The lead gasket being first cast
in the groove as described, the sections are joined as in Fig. 1, a pipe is screwed
into the opening b, and a suitable semi-fluid material, such as tar, is forced there-
through, finding its way between the lead gasket and the bottom of the annular
groove.
A forcing device or any suitable form may be employed for the purpose, and a
sufficient hydrostatic pressure is thereby communicated to the gasket to force or
compress it at all points into close contact with the male section, as shewn in
Fig. 2, forming a perfect fluid-tight joint; finally, the inlet pipe is removed and the
opening b filled with moist clay or any other suitable known material, and a screw
plug c inserted and screwed home, thus sealing the outlet under pressure.
Any known suitable semi-fluid substance may be used in forcing the gasket to
its seat, coal or wood tar boiled to a ropy consistency is a cheap material, and is
found to answer well by reason of its viscid nature; it will not readily escape
from any minute openings there may be between the lead gasket and the sides or
the groove in which it rests before the bydrostatic pressure is sufficient to start the
gasket from its normal position in the groove; when this occurs its inclined sides
bind firmly against the corresponding sides of the groove, thereby preventing the
escape of the tar. When the final pressure is reached the lateral enlargement of
the gasket contributes to this result.
The inner surface of the gasket may be made slightly concave, as shewn in
Fig. 1, for the reception of a semi-fluid packing material, such as red lead and oil,
of the consistency of a stiff paste, to be applied to the gasket before joining the
sections for the purpose of assisting in forming a perfect joint with less hydrostatic
pressure upon the gasket than would otherwise be required, in such case all the
soft material exhudes from between the contact surfaces, except that required
to fill minute spaces, while the use of soft packing is advantageous, particularly
in gas mains, where it is essential in forming a tight joint.
My improved joint is applicable to the usual ball-and-socket joint.
It is obvious that instead of using a lead ring adopted to a groove or channel
within the bell portion of the pipe as described, an annular tube of lead or other
suitable known material, wholly or partially collapsed, may be inserted between the
sections of the pipes as a packing, the same being then expanded or forced into
close contact with the pipes by means of fluid pressure (either liquid or gaseous)
applied through an opening communicating with the interior of the tubular gasket;
other material, such as rubber, may be substituted for the lead shewn, but such
mere modifications I consider wholly within the scope of my Invention, which
consists essentially in forcing a gasket or packing into fluid-tight contact with the
pipe sections by means of hydrostatic pressure applied externally or independently
of the pressure within the mains or pipes.
One or more grooves may be used furnished with packing material, such as lead,
india-rubber, or any known suitable substance for making or forming one joint
with a sleeve for uniting two sections of pipes together by hydrostatic pressure in
the manner herein-before stated When great pressures are used in water mains
to more fully prevent longitudinal displacement of the joint, the male pipe may be
furnished with grooves for receiving the gasket to prevent the pipes from being
longitudinally displaced by excessive internal pressures; however, for ordinary main
pipe pressure, this will not be required.

page_text: As before stated, any known suitable device, such as a properly constructed force
pump, or a single plunger screwing into a cylinder either attached directly to the
opening in the bell of the pipe, or connected therewith by a tube, may be used to
force the tar or other semi-fluid material into the groove, I have not considered it
necessary to describe in detail such device, since appropriate means will suggest
themselves to persons skilled in the art.