Mols-Linien ferry to have Rolls-Royce propulsion systems

DECEMBER 19, 2016 — Rolls-Royce will provide the main propellers and propulsion control system for the 158 m car and passenger ferry ordered at Finnish shipbuilder Rauma Marine Constructions (RMC) by Danish operator Mols-Linien (see earlier story).

Rolls-Royce will deliver two Promas system units, each integrating a controllable pitch propeller, propeller hub cap, and a rudder with bulb and a twisted leading edge into one hydrodynamically optimized unit.

Gearboxes, steering gears, two tunnel thrusters in the bow and a control system are also part of the delivery.

Gary Nutter, Rolls-Royce, Director Products, said: “By adapting the propeller and rudder into one propulsive unit, Promas offers increased propulsive efficiency and improved manoeuvrability. It is chosen by both conventional single and twin screw ships, such as the passenger ferry to be constructed for Mols-Linien.”

Included in the order are cavitation tests at the Rolls-Royce Hydrodynamic Research Center (HRC) in Kristinehamn, Sweden. At this advanced facility, the performance of the combined propeller and rudder system (Promas) will be controlled and tested prior to manufacturing.

The HRC includes a large cavitation tunnel where a model of the ship’s hull, with the ordered propulsion set up, will perform in different operating conditions. Model testing can lead to important and cost-saving adjustments in a product or ship design.

Göran Grunditz, Rolls-Royce, Manager HRC, said: “Cavitation tests are digitally documented and log efficiency, cavitation performance and risk of cavitation erosion on the equipment. The tests provide us, the yard and the owner with useful data related to estimated future fuel consumption and can also help the owner when planning for future services intervals.”

The Rolls-Royce Hydrodynamic Research Center is one of the world’s leading marine research facilities, specializing in the development of marine propulsion systems including the design and testing of propellers and water jets.