Digital Acoustic Upgrades for Semi-submersible Drilling Rigs

Both these rigs have been operating with Nautronix analogue RS912 USBL systems since the early nineties but have seen the substantial performance and acoustic reliability improvements that Nautronix ADS2 Digital Acoustics will deliver from the NASDrill USBL system in operation on their Songa Dee drilling rig.

NASDrill USBL systems have been designed specifically to meet the requirements for a reliable, stable and accurate position reference and riser angle monitoring system for demanding offshore operations for both moored and DP drilling rigs and can operate in both transponder and pinger modes, depending on customer requirements.

The NASDrill USBL system has been developed to meet positioning needs up to a 4,500 metre range with accuracy of 0.5m or 0.5% slant range including any motion errors based on interfacing to 0.1° dynamic accuracy VRU. This performance is achieved using a 225mm diameter interrogate/receive surface transponder avoiding the need for the large gate valves and expensive surface transducers used by some other suppliers.