|As Laid and As Built Pipeline Surveys|
The aim of the as-laid survey is to undertake a complete visual and instrumental ROV inspection along the pipeline as soon as the pipeline has been laid. The as-laid survey will define: the accurate position of the pipeline, the pipe-seabed configuration (visual and instrumental) and the external status of the pipe.
The as-built documentation will then be prepared by properly merging the results of the as-laid and as-built surveys.
During the as laid survey a complete visual and instrumental ROV inspection will be performed to gather the following information:
The R.O.V. can be equipped with Bathymetric Unit, Modular Scanning Profiler, Panoramic Sonar, Motion sensor & Gyrocompass, Center and Boom Color video cameras, Integral Comprehensive Video Overlay with video eventing
The vessel is provided of an adeguate area for data processing and interpretation, equipped with PCs, A0 plotters and digitizers. Charting and reporting of interpreted data are carried out onboard Odin Finder on a continuous basis throughout the duration of the survey.
In the last 5 years GAS has developped an internal Software named PIPEVIEWER, used for analize the MBES data. After the DTM creation the numeric analysis of the MBES data referred to natural seabed, pipeline TOP and trench will be elaborated by PipeViewer. The software provides TOP, BOP, BOT, OOS and NSB detection and the requested cartography for as-laid and as trenched surveys.