Abstract: A machine for surface preparation of a pipeline includes a vacuum shroud that encircles the pipeline. Three manifolds, each housing a plurality of ultra high pressure water nozzles, are mounted in the vacuum shroud at circumferentially spaced intervals. A carrier assembly advances the vacuum shroud along the pipeline at a rate that avoids contact between the water jets and uncoated pipe. The shroud also oscillates about a longitudinal axis of the pipeline so that a short extent of the pipeline is subjected to the force of the water for each oscillation. The vacuum in the shroud carries away all debris created by the coat-stripping process to a closed loop filtration and recycling system. The nozzles are mounted a constant stand-off distance from the pipeline to avoid creation of hot spots during the stripping process. All motions are electronically monitored and detection of any movement failure results in system shutdown.

Abstract: A machine for surface preparation of a pipeline includes a vacuum shroud that encircles the pipeline. Three manifolds, each housing a plurality of ultra high pressure water nozzles, are mounted in the vacuum shroud at circumferentially spaced intervals. A carrier assembly advances the vacuum shroud along the pipeline at a rate that avoids contact between the water jets and uncoated pipe. The shroud also oscillates about a longitudinal axis of the pipeline so that a short extent of the pipeline is subjected to the force of the water for each oscillation. The vacuum in the shroud carries away all debris created by the coat-stripping process to a closed loop filtration and recycling system. The nozzles are mounted a constant stand-off distance from the pipeline to avoid creation of hot spots during the stripping process. All motions are electronically monitored and detection of any movement failure results in system shutdown.