AlfaWall Oceanbird AB

Hydraulic flushing and pressure testing of Oceanbird’s wing sail

HydTec planned and carried out hydraulic flushing followed by pressure testing of six circuits in Oceanbird’s full-scale, land-based wing sail at Oresund DryDocks in Landskrona. The assignment included technical review, development of the six-loop flushing arrangement, flushing through the hydraulic swivel, and pressure testing of the hydraulic circuits.

Challenge

The wing sail contained multiple hydraulic circuits, including a six-channel swivel and flap-cylinder connections. The completed pipe and hose installation required controlled flushing and pressure testing before continued testing and operation.

Delivery

HydTec reviewed the specification, developed the six-loop flushing arrangement, mobilised suitable equipment and carried out hydraulic flushing followed by pressure testing at Oresund DryDocks in Landskrona.

Results

HydTec completed hydraulic flushing and subsequent pressure testing of the six circuits on Oceanbird’s land-based wing sail at Oresund DryDocks in Landskrona.

Image courtesy of Oceanbird

GO TO RESULTS

Initiation

Oceanbird’s full-scale Wing560 prototype in Landskrona, where HydTec carried out hydraulic flushing and pressure testing. Image courtesy of Oceanbird.

Initial assessment

Oceanbird was preparing its full-scale, land-based wing sail for continued testing and operation. Before this could proceed, the hydraulic pipe and hose circuits required flushing to a defined cleanliness level and pressure testing.

Following an initial meeting and the signing of an NDA, Oceanbird provided HydTec with a preliminary flushing specification. HydTec reviewed the material and requested additional information on circuit lengths, operating oil, required flow conditions and pressure testing so that the assignment could be properly dimensioned and planned.

Communication

HydTec and Oceanbird maintained continuous technical communication throughout the planning stage. The specification was progressively updated with revised schematics, pipe and hose lengths, flow requirements, flushing duration and pressure-test requirements.

HydTec supplied a proposed six-loop arrangement and example outputs demonstrating how its mobile equipment could document flushing performance and pressure-test curves. The final working method was agreed together with Oceanbird and the other technical parties involved.

Process

Design & Engineering

HydTec began by reviewing Oceanbird’s preliminary specification and hydraulic schematics. Additional information was requested regarding pipe and hose lengths, system volume, operating fluid, required cleanliness, flow conditions and pressure-test requirements.

Based on the updated information, HydTec developed a flushing arrangement dividing the installation into six controlled loops. The method included flushing through the hydraulic swivel while maintaining the required turbulent flow conditions throughout each circuit.

HydTec also reviewed the proposed flushing oil. Where technically possible, using the final operating fluid was recommended to reduce the risk of residual flushing oil contaminating the completed system.

Manufacturing

Together with Oceanbird and the other project parties, the method was refined to control flow velocity and allow the circuits to be flushed in both directions. A minimum flushing duration was specified even if the required cleanliness was indicated earlier.

Before mobilisation, the mounting status of the hoses and swivel was confirmed and the shipyard’s safety requirements were reviewed. HydTec then carried out hydraulic flushing followed by pressure testing on the land-based wing sail at Oresund DryDocks in Landskrona.

Results

Example of flushing results

Installation & commissioning

The work was performed on Oceanbird’s full-scale, land-based wing sail at Oresund DryDocks in Landskrona. Oceanbird completed mounting the hoses and the hydraulic swivel before HydTec arrived.

HydTec’s mobile flushing equipment was connected to the prepared hydraulic circuits in accordance with the agreed-upon six-loop arrangement.

After flushing, HydTec pressure-tested the hydraulic circuits.

Follow up & support

HydTec retains the technical basis and flushing-loop arrangement developed for the assignment and can support Oceanbird with further flushing, pressure testing, commissioning and related hydraulic service requirements.

Oceanbird's full-scale wing sail on a vessel deck at Oresund DryDocks in Landskrona, wind turbines visible at sunset.

Oceanbird’s Wing560 during installation onboard Tirranna. Image courtesy of Oceanbird.

Hydraulic flushing and pressure testing of Oceanbird’s wing sail