Pipetech was approached by CNRI UK to perform high pressure Aqua Milling cleaning of its 12″ Lyell Riser on the Ninian South platform prior to UT inspection.
Challenges
A specialist Aqua Milling team completed cleaning from entry point, 320 meters down to a subsea manifold and back. Aqua Milling on deployment and retrieval consisted of a polishing run to prepare the walls for UT inspection.
Cleaning at a rate of 1 foot per minute to ensure total effective cleaning of pipe wall internal. All waste / rust deposits were collected via EPAT and fluids pumped to the closed drains system.
Achievements
- Successful cleaning and recovery to required distance, 320 meters negotiating 9 bends from entry to SSIV.
- Workscope completed ahead of scheduled, reduced from 8 to 4 days.
- UT inspection data deemed acceptable after 2 cleaning runs.
- All waste fluids fully contained from pipeline to waste disposal through closed drains with no loss of containment and / or environmental impact.
Benefits
Safety – Fully contained remotely operated Aqua Milling system.
Flexibility – Work scope carried out utilizing the minimum of deck space as possible.
Performance – A skilled and experienced team, providing the excellent customer service and surpassing customer expectations.