METHODS AND APPARATUS FOR PURGING LIQUID FROM AN OFFSHORE PIPELINE AND/OR SCANNING A PIPELINE INTERIOR

摘要

ABSTRACT OF THE DISCLOSUREApparatus for purging water from a submerged pipelineincluding means for handling pipeline "pigs" (i.e., sphere,plug, or other device movable through a pipeline interior insliding peripheral engagement therewith). In the system ofthe invention a pig launcher is attached at a first pipelinemeans end and a pig receiver is attached at a second, sub-merged pipeline means end. The pig launcher is operable topropel a plurality of pig elements in sequence through thepipeline under the urging of pressurized gas in order to dis-place fluid and/or locate obstructions. The pig receiver isarranged to exhaust such displaced fluid and receive and storethe propelled pig elements. The pig receiver may include afluid discharge system for exhausting propulsion gas into theambient water in response to the arrival of a pig element andthus provide means to signal such arrival. The pig launchermay include a fluid discharge system for exhausting pressurizedpropulsion gas into the ambient water to signify a successfulpig launch.