Deepwater drilling poses special pressure-control problems. [Blowout control]

The critical relationship existing among the drilling mud density, circulating density, and rate at which pipe is handled in deepwater drilling is examined. The use of diverter systems to minimize the effects of a blowout is discussed. The problems provided by the riser-choke line are evaluated and the use of the system pressure loss in preventing blowouts is considered. The subsea stack and the riser margin are also discussed. (JSR)