Biggest coupling ever for CRP drive on VLCC
23 Jun 2003
Coupling for CRP drive is readied for shipment to Japan
The biggest torsional elastic coupling ever built is currently on its way from Austria to Japan. The coupling, which has an outer diameter of 2.8m, a weight of 36.3t and comprises more than 2,000 individual parts, is for a drive line with contra-rotating propeller on a VLCC that IHI Marine United?s Kure shipyard is currently building for Idemitsu Tanker Co. Geislinger, the coupling?s manufacturer, says the coupling will protect the gearbox that changes the rotational direction of the backward running propeller as it will transmit half of the 27,160kW (at 74 rev/min) power the Sulzer 7RTA84T main engine will produce. The company has also delivered an electronic system with sensors to monitor the coupling on the 300,500 dwt ship, named Nissho Maru, which is scheduled for delivery in July next year. While this is the largest contra-rotating propeller system built, shipyard, owner and manufacturer have all accumulated experience with smaller systems stretching back a number of years.