Norwegian Cruise Line is one of the leading Cruise lines in the world, with 11 ships in operation all over the world, including, with vessels covering the Caribbean, Mediterranean, Baltic, Alaska and Hawai, meaning the vessels operate within varying conditions.
Maintenance is of the highest importance to achieve stable, safe and reliable operation of the vessels.
With seven ships fitted with ABB Azipod propulsion systems, the cleanliness of the oil systems for both thrust bearings and propeller bearings is of the utmost importance.
The ships are installed with the Purifier bypass type filter units to keep the oil systems free of contaminants like particles and water. Water is generally caused by condensation when ships are operating in cold waters. So far outstanding results have been achieved
On the Norwegian Sky, Purifiner units are installed on both SB and PS stern tube systems, where a high content of water contamination had been found. A single unit on the SB system and a Twin unit on the PS, has reduced the water content a to a minimum.
With 8800 litres of total stern tube capacity, the small filtration units provided impressive performance onboard the Norwegian Sky.
The vessel also has one unit connected to aft stern thruster which due to wear and tear, has in the past, experienced been high iron content in its lubricating oil. Within a week of fitting a Purifiner filter, the iron content was reduced to acceptable limits.
Case study with thanks to Norwegian Cruise Line.