Refurbished Wollaston Subsea Tree & Auxiliary Equipment
Background
A major offshore operator engaged Hydrus to complete the full refurbishment and mobilisation of a Subsea Tree and associated auxiliary equipment, including a Tree Cap. These components are critical to subsea production systems, forming the interface between the wellhead and production equipment. Over time, operational wear and exposure to harsh subsea conditions can compromise performance, requiring expert refurbishment to restore functionality and ensure safe redeployment.
Hydrus’s workshop facilities, equipped with overhead handling, high-pressure testing systems, and a skilled team of technicians, were ideally suited to carry out this demanding scope of work. With a reputation for precision engineering and fast turnaround, Hydrus was selected to deliver the complete refurbishment and testing programme, readying the system for offshore operations.
The Project
Hydrus delivered a comprehensive work scope, beginning with the full disassembly and inspection of the Tree Cap and auxiliary components. Every item was assessed for wear, corrosion, and mechanical integrity.
Scope of Work
- Tree Cap Disassembly – The cap was fully stripped down for detailed inspection and servicing.
- Surface Preparation – All components were cleaned, blasted, and coated to extend their operational life and resist corrosion in subsea conditions.
- Hydraulic Cylinder Refurbishment – Cylinders were dismantled, refurbished, tested, and reassembled, ensuring reliable actuation in service.
- Full Equipment Assembly – Hydrus reassembled the Subsea Tree and all auxiliary systems, integrating refurbished components and completing alignment and interface checks.
- System Integration Testing (SIT) – A full internal SIT was conducted to validate functionality under controlled conditions.
- Final Certification – All work was verified by third-party inspectors to ensure compliance with client and industry standards.
The Results
The refurbished Subsea Tree and auxiliary equipment were successfully mobilised for redeployment, fully certified and tested. Hydrus delivered the project on schedule, restoring the system to full operational readiness. This project further reinforces Hydrus’s position as a trusted partner for high-integrity subsea refurbishment and testing.
