Hydrocleaning of the exterior surface of a pipeline to remove coatings.

摘要

Apparatus for the hydrocleaning of the exterior surface of a pipeline or the like includes a frame (212) adapted to surround a portion of a pipeline and defining a longitudinal passage through which, in use, the pipeline extends. A plurality of liquid jet nozzles (314) are mounted to the frame (212) in spaced apart relation so as to surround, in use, said pipeline in circumferentially spaced apart relationship to one another with each nozzle (314) in spaced relation to the pipeline exterior surface. Means for supplying high pressure liquid to the nozzles (314) to cause liquid jets to be emitted from the nozzles (314) are provided. The nozzles (314) and the frame (212) are adapted to move relative to the pipeline surface when in operation such that (i) the liquid jets from the nozzles (314) impinge on the pipeline surface along prescribed paths located in an annular region extending around substantially the full circumferential extent of the pipeline and (ii) the annular region travels longitudinally relative to the pipeline to effect cleaning of the pipeline exterior surface. In one form of the machine the frame (212) "opens" up to permit installation on an "in situ" pipeline.