IMPROVEMENTS RELATING TO THE CLEANING OF PIPELINES AND PASSAGEWAYS

摘要

The invention provides a method of removing detritus (12) from the bottom of an underground pipe (10) in which liquid flows. The method involves everting into the pipe and over the detritus two air filled tubes (46), the tubes (46) block the liquid flow and the liquid (14) builds up until a sufficient head (56) causes the liquid to be forced past the underside of the everting tubes at the everting faces at high velocity so as to erode and break up the detritus (12) which is swept away and can be sucked out of the pipe (10). Removal is progressive in that as the detritus (12) is removed from downstream to upstream, so the tubes (46) are progressively everted along the pipe (10). The detritus (12) may be pre-disturbed by a mechanical plough (24).