July 1 - Damen Shiprepair Amsterdam (DSAm) has concluded major modification works, including the extension of the main boom, on A2SEA's offshore wind farm installation vessel Sea Installer.

The boom extension has increased the reach capacity of Sea Installer, allowing the vessel to handle the ever-increasing size of offshore wind turbine components.

DSAm - part of Damen Shiprepair & Conversion - began the work by removing all crane-related components including the boom, boom rest, A-frame, winch and hook block pockets from the vessel.

A2SEA supplied the new A-frame and boom extension; while Niron Staal, also part of Damen Shiprepair & Conversion, supplied the new boom rest, hook block pockets, trolley rail and support stools.

The crane boom was lengthened by inserting the new extension, explained DSAm. All parts were composed of high tensile S690 steel, which needed to be cut and welded at the correct temperature - an operation that you cannot rush, said DSAm.

The configuration of the upgraded crane means that it can be operated in two modes - a long mode with the crane boom extension, and a short mode with the extension removed.

Sea Installer now has a flexible crane capacity of 900 tonnes in short mode and 700 tonnes in long mode.

Two Mammoet cranes were used to lift the extended crane boom onto the vessel.