The Swagelining process is a
cost-effective pipeline lining technology developed by BG plc
(formerly British Gas plc) in the late 1980s. The process
allows a tight-fitting polyethylene (PE) liner to be rapidly
installed in a pipeline without significantly reducing the
diameter of the host pipe.
The
Swagelining
process uses PE pipe which has an outside diameter slightly
larger than the inside diameter of the pipe to be lined.
During the installation process, the PE pipe is pulled through
a die to temporarily reduce its outside diameter. This
reduction allows the PE to be easily pulled through the host
pipe by a winch. When the pulling force has been disconnected,
the PE pipe begins to return toward its original diameter.
However, just before the PE pipe relaxes completely it presses
tightly against the inside of the host pipe, eliminating all
annular space and creating a close fit
lining.
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