Project Background:
The "Ocean Star" cargo vessel has been in operation for 8 years and requires a comprehensive assessment of its underwater hull before entering dry dock for repairs. Due to poor visibility and complex currents in the port, an underwater remotely operated vehicle (ROV) was deployed to conduct the inspection, ensuring safety and efficiency compared to traditional diver-based methods.
Equipment Overview:
The "Deep Blue Explorer-III" ROV was utilized, equipped with high-definition cameras, sonar, laser rangefinders, and robotic arms, enabling precise navigation and operational capabilities.
Workflow:
1. Planning and Deployment: Ship drawings and hydrological data were analyzed to divide inspection areas and define key checkpoints. The equipment was deployed and calibrated for positioning.
2. Autonomous Inspection: The ROV scanned the hull bottom, sides, propellers, and other areas, identifying issues such as coating detachment, biofouling, and minor corrosion.
3. Re-inspection and Analysis: Targeted re-inspection of abnormal areas was conducted, and all data were integrated to generate a 3D visual inspection report.
Key Findings:
• The hull structure was generally in good condition with no significant damage.
• 85% of the coating remained intact, with approximately 3.2 m² requiring repair.
• Moderate biofouling was observed, and minor cavitation was found on the propeller blades.
• The maximum corrosion depth was 1.2 mm, and no cracks were detected in any welds.
Outcomes:
The entire inspection took approximately 10.5 hours, improving efficiency by about 40% compared to traditional diver inspections. The report provided specific repair recommendations, enabling the shipowner to develop a precise maintenance plan and save both time and costs. This operation validated the safety, efficiency, and accuracy of using ROVs for hull inspections in complex environments, offering a reliable new solution for vessel maintenance.