HOUSTON -- Two Schlumberger technologies are Spotlight Award winners this year at the Offshore Technology Conference. The SenTURIAN electrohydraulic subsea landing string and the subC-racs riser annulus surveillance system both are recognized.
The SenTURIAN is designed to operate from a dynamically positioned vessel in deepwater and high-temperature/high-pressure applications. The system uses interchangeable mandrels and pressure-balanced accumulators to combine both subsea control and accumulator modules into one assembly.
Schlumberger says the new system is the only in-riser system certified to IEC 61508 SIL 2 specifications for safety-related systems. It also complies with ISO 13628 by having electronic redundancy and pressure readout for each subsea function.
The subC-racs riser annulus surveillance tool is a joint development by Schlumberger and Total. It automatically monitors flexible riser integrity and vented emissions. In the main, it measures dry volume of the annulus and flow rates of gas and water vapor.
The trends in these measurements are vital data in assessing integrity of the riser for several failure drivers. These drivers include high concentrations of dissolved CO2 or H2S, condensation in the riser annulus, flow increases, and seawater ingress, says Schlumberger. SubC-racs continuously monitors for these indicators and identifies these sorts of trends before fatigue damage is evident.