The material then bonds to the inside of the pipe and the resin cures or hardens, creating a new pipe within the pipe and restoring the integrity of the drain or sewer.

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The second suggests that a rod-like plug can block the hole by slipping across it sideways and stopping large ions from passing, rather like a drain cover stops leaves from entering the mouth of a pipe.

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Network Rail said workers were laying a pipe underneath the track to allow the water to drain away onto the other side.

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