Undersea well with single bore riser has valve connecting annular space passages between rising column and riser

摘要

Undersea well uses valve to connect annular space passages between rising column and riser (10). Column has connector (26) supported on upper end of riser. Connector has production passage (30) and annular space opening (32). Internal shaft cowl (16) is positioned in riser. Production passage goes through cowl and annular space passage (22) communicates with upper surface of cowl and shaft annular space passage. Valve is positioned in container (24) at upper end of annular space passage. Part of valve extends above cowl to open when connector is supported on cowl.