Posted on December 10, 2020
Dutch company Z-Bridge has developed a motion compensated personnel transfer system that is compact enough to be fitted to crew transfer vessels.
Z-Bridge’s B2W (Bring to Work) design is intended to be a lightweight and efficient access system with the objective of optimising visit times by transporting a small team of up to six persons in one transfer in an elevator type cage. The system will allow the safer direct transfer of personnel from the deck of the CTV onto the wind turbine or other offshore structures. With an elevation range of from 10m to 25m the B2W should allow for access operations to use existing landing points and platforms on turbine towers. This should save on fabrication costs by removing the need for access structures to be fitted to the deck of the vessel or the landing platform.
The system comprises a deck mounted base that can rotate under hydraulic control. Attached to this is a telescopic arm that can be extended and varied in elevation with the whole system under computer control that allows the arm to maintain contact with the turbine structure whatever the motions of the CTV. Attached to the arm is a small platform that can travel up and down the arm, again under hydraulic control, which acts as the personnel transfer platform once the transfer arm is engaged with the turbine tower.
The B2W system is reported to weigh in at 25 tonnes and combined with a small deck footprint it is claimed this will make it suitable for fitting to larger CTV’s. It is hoped that this will create a more efficient and safer means of transferring personnel and reduce costs. The system can also be used as a 3D motion compensated crane, capable of hosting up to 3 tonnes, potentially making the B2W concept suitable for installation and commissioning operations.
The B2W is being approved by Bureau Veritas and following harbour trials it is planned to install the prototype on the 32 metre long CTV MHO-Esbjerg, which is owned by MHO-Co for offshore trials in the near future. Z-Bridge has extensive experience of motion compensated transfer systems with their larger W2W systems for larger vessels.
By Dag Pike