Abstract: A casing drilling system includes combination conduit of a casing and a pipe inside the casing. A first adapter has a flow diverter to redirect at least flow of drilling fluid returning from a bottom of a wellbore to either an interior of the pipe or an annular space between the casing and the pipe. A second adapter has a flow diverter to redirect flow of drilling fluid into the conduit through the other one of the interior of the pipe and the annular space. The second adapter has a fluid connection between either the interior of the pipe or the annular space and a rotationally fixed fluid outlet. The system includes a casing chuck having means to support the casing and a slidable conduit operable to expose an uppermost end of the casing and a connection between the second adapter and an uppermost end of the pipe.

Abstract: A dual drill string actuator includes a piston disposed in a housing. The housing is configured to sealingly couple at its longitudinal ends to an end of a nested dual drill string segment. An upper internal conduit is mounted in the housing proximate one longitudinal end thereof. A lower internal conduit is mounted in the housing proximate the other longitudinal end thereof. The piston is slidably, sealingly engaged between the upper and lower inner conduits and together define an internal fluid flow passage therethrough. The upper inner conduit, the piston and the lower inner conduit also define an external flow passage between respective exterior surfaces thereof and an interior of the housing such that application of fluid pressure to the external flow passage causes movement of the piston.

Abstract: A casing drilling system includes combination conduit of a casing and a pipe inside the casing. A first adapter has a flow diverter to redirect at least flow of drilling fluid returning from a bottom of a wellbore to either an interior of the pipe or an annular space between the casing and the pipe. A second adapter has a flow diverter to redirect flow of drilling fluid into the conduit through the other one of the interior of the pipe and the annular space. The second adapter has a fluid connection between either the interior of the pipe or the annular space and a rotationally fixed fluid outlet. The system includes a casing chuck having means to support the casing and a slidable conduit operable to expose an uppermost end of the casing and a connection between the second adapter and an uppermost end of the pipe.

Abstract: A dual drill string valve includes an actuator including a piston disposed in a housing. The housing is configured to couple at its ends to an end of a nested dual drill string segment. An upper internal conduit is mounted in the housing proximate one longitudinal end thereof. A lower internal conduit is mounted in the housing proximate the other longitudinal end thereof. The piston is slidably, sealingly engaged between the upper and lower inner conduits and defines a fluid flow passage therethrough. The upper inner conduit, the piston and the lower inner conduit define another flow passage between respective exterior surfaces thereof and an interior of the housing such that application of fluid pressure to the external flow passage causes movement of the piston away from the upper inner conduit. A rotary valve is coupled to the actuator whereby longitudinal movement thereof rotates the rotary valve.

Abstract: The present invention regards a sealing arrangement for a valve, comprising a valve element (3) provided with a sealing element (4), arranged to be abutting a valve seat (2) in a closed state of the valve. The valve element (3) comprises at least two parts, a first and second part (31,32), each comprising an abutting surface (310,320), which abutting surfaces (310,320) are arranged facing each other and to abut against corresponding sealing element surfaces (41,42) of the sealing element (4), and whereof at least one part (31) of the valve element (3) is being arranged to be moveable relative another part (32) of the valve element (3) and the at least one part (31) of the valve element (3) comprises a pressure surface (311) exposed to a surrounding fluid in a closed state of the valve giving pressure on the sealing element (4) responsive to the pressure in the surrounding fluid.

Abstract: A dual drill string valve includes an actuator including a piston disposed in a housing. The housing is configured to couple at its ends to an end of a nested dual drill string segment. An upper internal conduit is mounted in the housing proximate one longitudinal end thereof. A lower internal conduit is mounted in the housing proximate the other longitudinal end thereof. The piston is slidably, sealingly engaged between the upper and lower inner conduits and defines a fluid flow passage therethrough. The upper inner conduit, the piston and the lower inner conduit define another flow passage between respective exterior surfaces thereof and an interior of the housing such that application of fluid pressure to the external flow passage causes movement of the piston away from the upper inner conduit. A rotary valve is coupled to the actuator whereby longitudinal movement thereof rotates the rotary valve.

Abstract: The present invention regards a sealing arrangement for a valve, comprising a valve element (3) provided with a sealing element (4), arranged to be abutting a valve seat (2) in a closed state of the valve. The valve element (3) comprises at least two parts, a first and second part (31,32), each comprising an abutting surface (310,320), which abutting surfaces (310,320) are arranged facing each other and to abut against corresponding sealing element surfaces (41,42) of the sealing element (4), and whereof at least one part (31) of the valve element (3) is being arranged to be moveable relative another part (32) of the valve element (3) and the at least one part (31) of the valve element (3) comprises a pressure surface (311) exposed to a surrounding fluid in a closed state of the valve giving pressure on the sealing element (4) responsive to the pressure in the surrounding fluid.