Ranger 2 USBL on World’s Largest Offshore Construction Vessel
The Swiss Allseas Group has selected Sonardyne’s Ranger 2 Ultra-Short Baseline (USBL) acoustic positioning system for the world’s largest pipelay and platform installation/decommissioning vessel, Pieter Schelte.
The Ranger 2 USBL system will be used as a high-precision independent acoustic reference for the vessel’s Kongsberg dynamic positioning (DP) system during structure installation or pipelay operations when maintaining a steady position is a critical requirement. The Sonardyne system measures the range and bearing from a vessel-mounted acoustic transceiver to a transponder deployed on the seabed or attached to a pipe as it is lowered from the surface. The vessel’s relative position to the transponder is continuously reported to the DP system in order that the vessel can be manoeuvred to remain in the required location.
Built by Daewoo Heavy Industries in South Korea, at 382 metres long and 124 metres wide, Pieter Schelte is almost as long as the Empire State Building and as wide as London’s Big Ben is tall. When complete early next year, the vessel will be able to lift loads of 48,000 tonnes and has sufficient deck space to deliver or remove a complete topside module and jacket in one trip.
A key factor in Allseas’ decision to select Sonardyne acoustics for their vessel was Ranger 2’s ability to deliver fast, accurate and repeatable position updates in all water depths and operating conditions. This performance comes as a result of the digital wideband signal technology and Sonardyne 6G hardware platform on which the system is built. As many field developments projects around the world now specify 6G-equipped vessels, Pieter Schelte will be able to arrive at a location and begin working alongside other vessels without any delay or interruption to ongoing subsea operations.
