Late last year, the Damen group completed a project to replace one of the twin rudder stocks on P&O Ferries’ ‘Pride of Canterbury’.
The 180 m long, 30,635 gt ropax operates on the Dover/Calais crossing. The nearly 30-year old vessel is equipped with twin patented Van der Velden BARKE rudder systems engineered and manufactured by Damen Marine Components (DMC). Replacing the stock on the starboard rudder enabled the ferry to extend its already long life in such a demanding role.
Three Damen companies working together were involved in the project. Damen Verolme Rotterdam (DVR) hosted the vessel while DMC co-ordinated the project and managed assisting service engineers from DVR and Damen Shiprepair Rotterdam (DSR).
Work began with the removal of the rudder and its stock which took place in DVR’s No. 5 drydock at Botlek. The rudder together with its worn stock was then transported by road to nearby DSR where it was disassembled and the parts cleaned. Meanwhile, DMC had designed and supplied the new rudder stock and delivered it to DSR, ahead of the installation.
The most technically exacting part of the project was the fitting of the new stock to the rudder. This had to be done to the finest tolerances using techniques, including bluefit to ensure optimal performance, and it had its risks. Any machining errors that would affect the positioning and finish, would mean that the stock would have to be discarded and refabricated, with the high cost involved both in time and money.
Fitting took place at DSR and to ensure that the process went perfectly, experienced service engineers from the sister companies teamed up under the guidance of DMC and used the old rudder stock for a trial fit. This determined the exact values that the replacement stock would need to meet in order to fit the rudder blade perfectly. Tests took place during the machining in order to ensure that the process continued on track.
With the new rudder stock fitted to the correct values, the blade was hung vertically and the new stock inserted to confirm that it fitted. The two parts were then transported to DVR and mounted on board the vessel where the gap between the rudder stock and blade was measured and determined to be exactly as specified. Finally, the rudder and steering gear were prepared for operations and a swing-test was performed to confirm that everything worked perfectly.
“We completed the entire project on time and without any delays by bringing together skills and resources from across the Damen Group,” Walter Treffers, DMC Area Manager Service Sales, explained. “For the shipowner it was crucial to have the ship out of the dock on schedule, and this was achieved thanks to the excellent co-operation and daily meetings between the yard, DMC, DVR and DSR.”