CLD rigs, MPD change equation for deepwater well control

Closed loop drilling (CLD) systems and managed pressure drilling (MPD) are challenging long-held industry ideas about well control. MPD builds on the inherent characteristics of a closed loop system. Within this contained, pressurized wellbore environment, pressure is closely monitored. Pressure changes, such as those caused by an influx, loss, or ballooning, are rapidly detected and controlled in increments as small as a few barrels. The MPD control response is initiated at the surface by automatically or manually varying the annular backpressure by using a specialized MPD choke manifold. These changes within the closed fluid system are used to manipulate downhole pressure without the delay, cost, and imprecision of changing mud weight. MPD's proactive and reactive response to riser gas results in a safer, more effective solution. The operator, rig contractor, and service company work together to integrate the enhanced well control capabilities of the MPD system, thus bridging the gap between traditional primary and secondary well control.