Geo Oceans and Vertech were engaged to plan and execute a ballast tank special survey inspection campaign using the Mini-ROV Class Survey System (CSS) on an FPSO. Four ballast tanks were surveyed with the ROV operated from the accommodation module of the FPSO. GVI and CVI High definition video, laser scaling, 3D modelling, high pressure blasting and ultrasonic thickness measurement data were captured and witnessed by the attending Lloyds Register surveyor.
The scope highlights include:
• Water Ballast Tanks Special Survey No. 4 (SS4) by Mini ROV
• 2 x simultaneous ROV work fronts in different tanks (two ROV teams on site)
• Class approved workpack creation, planning, & scope execution
• GVI, CVI, photographic & video inspections
• Surface cleaning of corroded areas for CVI and UTM using HP blasting systems
• UTM inspections across all plates for SS4 (approx. 1,000 UTM readings per tank) and on corroded areas/anomalies
• Crop & renew survey, laser scaling for measurement and markup, suggested renewals & steel tonnage calculations
• Anomaly inspections.