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Bidirectional 12-in. – Subsea Fuel Transfer Pipelines
Dexon Technology was tasked with inspecting two 12-in. subsea pipelines transporting jet fuel and diesel from an onshore pumping station to a sea berth. Inspectors minimized downtime and avoided installation of an offshore receiver.
Overview
Key challenge:
Inspect two 12-in. subsea fuel transfer pipelines while minimizing shutdown time and avoiding the installation of a receiver at the sea berth.
Project Details
• Diameter: 12-in.
• Length: 1 km × 2
• Type: Subsea jet fuel & diesel transfer pipelines
• Inspection Medium: Jet fuel
• Threats Assessed: Corrosion/metal loss
• Location: Offshore/onshore
• Continent: Asia, Thailand
• Tool: Customized UT-MC Ring ultrasonic inspection tool
Challenges & Solutions
Challenge 1:
• Standard UT-MC Ring configuration was not optimized for bidirectional navigation through tight bends
Solution:
• Customized the UT-MC Ring with a compact, joint-free design to reduce the risk of sticking during return travel
• Redesigned and condensed electronics, storage, and transducer systems into a shorter inspection body
• Retained high-resolution corrosion and metal loss inspection capability with ±0.3 mm accuracy
Challenge 2:
• Pipeline configuration lacked a launcher and receiver system
Solution:
• Designed and fabricated a bespoke onshore launcher using operator pipeline drawings
• Eliminated the need for an offshore receiver installation at the sea berth through a bidirectional run, reducing shutdown duration and operational cost
• Provided the launcher design to the operator to support future operations
Challenge 3:
• Tight shipping schedules required rapid inspection execution with minimal operational disruption
Solution:
• Executed the bidirectional inspection run in just over two hours while maintaining inspection quality standards
• Reviewed and validated inspection data immediately following the run to confirm data quality compliance
Conclusion
Dexon Technology successfully completed the inspection of both 12-in. subsea fuel transfer pipelines using a customized bidirectional inspection solution.
Through modification of the UT-MC Ring and development of a bespoke launcher system, Dexon minimized downtime, reduced operational cost, and delivered reliable corrosion and metal loss data while maintaining uninterrupted fuel transfer operations.