Abstract: An apparatus includes a conduit forming part of a drilling fluid return path from a wellbore. The the conduit has at least one well outflow control in the conduit. The at least one well fluid outflow control has at least two annular flow restrictors each separately operable to close to a respective inner diameter.

Abstract: A holddown assembly is provided for axially securing a pump in a wellbore. The assembly has a mandrel having at least one resilient holding element and at least one resilient sealing element. The holding elements are made of a durable material and configured to require a pre-determined seating force to seat the assembly in a seating tubular, and a pre-determined unseating force to unseat the assembly. The holding elements are configured to elastically deform when seated, such that the pre-determined seating and unseating force does not change significantly even over many seating/unseating cycles. The sealing elements are configured to sealingly engage with the seating tubular to prevent wellbore fluid from flowing thereby. As the sealing elements are only used for forming a fluid seal, and not for securing the pump, damage to the sealing elements as a result of repeated seatings and unseatings is mitigated.

Abstract: An annular blowout preventer includes a housing, an annular packer positioned within the housing, and an annular piston assembly positioned within the housing. An annular contacting surface of the annular piston is configured to contact the annular packer while the annular blowout preventer is in the open position. The annular blowout preventer also includes a plurality of inserts extending axially through the annular packer and arranged circumferentially within the annular packer. The annular piston is configured to drive the annular packer in an axial direction within the housing, thereby compressing the annular packer, causing the plurality of inserts to rotate radially inwardly, and moving the annular blowout preventer from the open position to a closed position.

Abstract: A blowout preventer assembly comprising an annular blowout preventer having an annular packing unit and an actuator operable to reduce the internal diameter of the annular packing unit, wherein the assembly further comprises a stripping sleeve having a tubular elastomeric sleeve which in use is positioned generally centrally of the packing unit so that the packing unit surrounds at least a portion of the elastomeric sleeve.

Abstract: Control lines on the outer surface of a tubular disposed within a drilling riser casing may be encapsulated to facilitate formation of a seal in an annular space defined by an inner surface of the drilling riser casing and an outer surface of the tubular. More specifically, an encapsulation body may be configured to at least partially encase control lines. The encapsulation body may include a first surface and a second surface. The first surface may have an arcuate shape that corresponds to the outer surface of the tubular to facilitate formation of a seal between the first surface of the encapsulation body and the outer surface of the tubular when the first surface of the encapsulation body abuts the outer surface of the tubular. The second surface may be shaped to provide a geometrically continuous periphery about the tubular and the encapsulation body when the first surface of the encapsulation body abuts the outer surface of the tubular.

Abstract: A threaded joint comprises a pin coupled to a box with an annular groove, one or a pair of seal rings, and hydraulic actuating means to pressurize the seal ring or rings against the pin to provide sealability of the joint. The seal ring or rings comprise a frustoconical surface, an external surface, and an internal surface with one or more protruding annular ribs. In the unpressurized state, the seal ring or rings do not protrude from the groove. In the pressurized state, the frustoconical surface of the sealing ring is in sealing contact with an internal surface of the annular groove of the box, and the annular ribs of the sealing ring are in sealing contact with the external surface of the pin.