Houlder led the Life Extension Upgrade for the Orelia Dive Support vessel. The upgrade provided new accommodation, new equipment, overhauled propulsion and a new hull form that significantly improved transit speeds and overall fuel efficiency.

The Technip owned vessel, built in 1984 at Swan Hunter Shipbuilders, was originally designed by Houlder Offshore Engineering for operations in the North Sea. It is a barge-shaped monohull Diving Support Vessel (DSV) designed to deliver maximum operability, primarily in the North Sea. It achieves this through superior vessel motions with roll and pitch characteristics comparable to a semi-submersible in operational sea states from 1m to 4.5m significant wave height.

The upgrade resulted higher quality accommodation with fewer shared cabins and a significant reduction in noise levels. In all, 34 non compliances to the International Labour Code [C92, C133] were eradicated and Comfort Class 2 was achieved with a noise reduction of over 10db.

Experience in service shows the changes in hull shape during the vessel’s refit led to an increased transit speed of 9.1 knots – a significant improvement on the target of 6.5 knots.

Houlder worked with Technip UK to initially define the scope of work and project requirements. Detailed designs were produced through Houlder’s Naval Architects and Marine Engineers and developed for Class Approval.

As well as design, Houlder was also accountable for writing the shipyard specification and assisting with yard selection. Houlder personnel then provided technical support, including yard supervision and commissioning throughout.