Page 39: of Marine Technology Magazine (September 2012)

the shaft line of each driven by two vari- able speed electric motors through twin in-single out reduction gears type Scana Propulsion ACGTS 1000. All diesel engines have selective cata- lyst reactor (SCR) units, supplied by H+H Umwelt, to reduce NOx emissions. NO2 emissions are reduced by some 90% to 98%, soot by 20% to 30% and hydro-carbon emissions by 80% to 90%. There are two ABB electric propulsion motors in parallel conÞ guration on each side, each motor 0-2200ekW, 0-1000rpm. The two controllable pitch propellers in nozzles, supplied by Scana Propulsion, each absorb 4400kW at 160rpm and have a diameter of 3700mm. There is an Caterpillar emer- gency generator with a power of 240ekW. The vessel runs on marine gas oil (MGO) with low sulphur content. The Fuel oil (MDO) capacity is 2030 cu.m. and fresh water capacity 1032 cu.m.. The vessel can also carry ballast water/tech. fresh water 2170 cu.m., lube oil 63 cu.m., and urea for the catalysts reactors 289 cu.m. Towing pull in seismic operation is 82t. Bollard pull exceeds 125t. Polarcus Adi- ra has a maximum speed of 17 knots, at 5.5m draft. There is one 1200kW tunnel thruster for- ward equipped with a controllable pitch propeller and one 850 kW retractable azi-muth thruster forward. There is one tunnel thruster aft, 830 kW, controllable pitch. The vessel is equipped with a roll damp- ing tank system. There are two fresh water generators, each producing 15 cu.m./24h. There are two fuel oil separa- tors, self cleaning type and three lube oil separators. In addition there is one mo-bile hydraulic oil separator and a USCG approved bilge water separator. A ballast water treatment system is installed. Switchboards, navigation and DP Ulstein Power & Control has delivered the switchboards 690V, 400V and 230V, the emergency switchboard, and the com- munication and information system type Ulstein COM¨ to the vessel. Alse the bridge control and navigation system is of Ulstein delivery. The vessel has a Kongsberg Maritime Dynamic positioning system, DP2 type, www.seadiscovery.com MTR #7 (34-49).indd 39MTR #7 (34-49).indd 399/10/2012 9:43:45 AM9/10/2012 9:43:45 AM