Well Control in Case of Offshore Blowout: Combined Casing and Tubing Shut-In Devices, BOS and Use of Shear Rams on Completed Wells

摘要

Only two methods which can shut in annulus and tubing to prevent or stop blowout quickly have been identified: (1) A shear ram BOP on top of the casing hanger around an extended prod. casing and below the tubing head. (2) BOS, a crimper placed in an expanded annulus outside special crimping joints of production casing and tubing. BOS competes with a separate annulus shut-in valve combined with tubing retrievable DHSV. Both BOP shear ram and BOS are recommended for further study.