IMPROVEMENTS IN THE MANUFACTURE OF PIPE JOINTS
Year: 1879

page_text: PROVISIONAL SPECIFICATION left by George Henry Ellis at the Office of
the Commissioners of Patents on the 18th October 1879.
GEORGE HENRY ELLIS, of No. 37, Walbrook, in the City of London, Engineer,
and CHARLES LLEWELLYN LIGHT, of No. 11, Little Queen Street, Westminster,
Civil Engineer.
"IMPROVEMENTS IN THE MANUFACTURE OF PIPE JOINTS."
This Invention relates to improvements in the manufacture of or method of
forming joints for earthenware, stoneware, fire clay, glass, cement, and similar
pipes, the object of the improvements being to obtain in a simple and economical
manner a sealed joint, and one which while it shall prevent the pipes being easily
drawn apart, shall at the same time allow of a certain amount of "sagging" for
the purpose of preventing the breakage of the pipe or injury to the joint in the
event of unequal pressure by the sinking of the ground in which the pipes are laid
or other causes.
In carrying out our Invention we form the spigot end of the pipe hemispherical
in form, or with a hemispherical flange, the interior of the socket end of the pipe
being formed of a corresponding hemispherical shape. On the periphery of the
spigot end of the pipe we form an annular groove, a similar groove being formed
in the socket so that when the two ends are placed one within the other the said
grooves will correspond, one or more openings on the periphery of the socket
communicating with the said annular groove.
By this construction it is simply necessary in order to join two pipes to insert
the spigot end of one into the socket end of the other, thereby forming a water tight
joint, and then to pour any suitable cement through the herein before described
opening or openings in the periphery of the socket, until the annular cavity formed
by the two annular grooves is filled up, and we prefer to employ for this purpose a
cement which when cool or hard shall be somewhat flexible and compressible.
It will be understood that this annular filling will prevent the pipes being
drawn asunder lengthwise, will seal the joint, while at the same time if from the
sinking of the ground or otherwise the joint should be subjected to undue pressure,
the hemispherical form of the ends of the pipes and the flexibility of the filling
material will allow a certain amount of "sagging" and curving of the line of the
pipes without injury to the joint or breakage of the pipes. Should it be necessary
to disjoint the pipes it will be merely necessary to soften or melt the hereinbefore
described cement or filling, whereupon the pipes can be drawn asunder without
injury.

page_text: One of the difficulties hitherto existing in obtaining good joints for earthenwar
stoneware, and similar pipes which are burned after they are moulded, has arisen
from the irregularity in the form or sizes of the spigot and socket ends of the pipes,
and our Invention relates to grinding the said ends (after the pipes have been
burned) by any suitable means by machinery specially designed for the purpose,
thereby obtaining a good fit when the parts are put together, and this part of our
Invention is applicable to pipes constructed of the form hereinbefore described or
otherwise where a good fit is required. It will be understood that when this
method is employed, the diameter of the spigot end of the pipe must be moulded
somewhat larger than hitherto, and the interior diameter of the socket of corre-
sponding form to allow of the two parts being ground to fit, thus forming a
flexible watertight joint.
Our improvements are equally applicable to straight ended pipes which are
connected together by loose sleeves or collars.