This application of the VLS measured a pipe dent subsea which was located in approximately 5000ft water depth. Pipeline diameters were 14 and 10 inches. The goal of the inspection was to create a model of the pipe surfaces to provide to an engineering company for further analysis by FEA.
Data Capture
A data collection procedure was created to outline the tasks and 2 technicians were sent to the vessel. SubC Imaging HD ROV Cameras were specified as the HD video cameras required for the data collection.
Project Scope
Once offshore, the first step in the process was to expose the area of the pipeline that was dented. This was achieved by an ROV mounted dredge system. An area around the dent was cleared to ensure that the ROV could access both sides of the pipeline as well as the underside of the pipeline.
Results
A video was taken on each side of the pipes and the total flying time for the operation was approximately 30 minutes per pipe. In this timeframe adequate data to reconstruct the pipe section was obtained. The data was taken back to the office and processed to create a point cloud of the dented durface. The final information was then passed on to the engineering company for final analysis.
• Total Data Collection Time (after site preparation): 60 minutes
• Accuracy Achieved: +/- 0.3 mm (at 2 sigmas)
