Abstract: The invention relates to a centralization and running tool (CTR) in a subsea installation in connection with offshore related oil and gas exploration, where the subsea installation (SCM) is arranged to be placed on the ocean bottom or a drilling template and comprises a pipe-formed body (10), at least partially open at the top and extended, arranged to receive and carry through a drill stem (12) from a drilling rig or a drilling vessel. The centralization and running tool (20) is arranged to surround the drill stem (12) and to be placed in the pipe-formed body (10), and the centralization and running tool (20) comprises, together with the drill stem (12), a rotary packing housing (22) with a number of seals (24,26) that lie against the drill stem (12), and the packing housing (22), in accordance with the movements of the drill stem (12), is arranged for radial movement to take up angular deviations of the drill stem (12).

Abstract: A method for the pressure regulation of a well (1) extending into a well formation (2) and being drilled from a drilling vessel at sea, the well (1) including a blowout preventer (10) on the seabed (12) and a riser (14) extending from the blowout preventer (10) up to the vessel, and the return path (8, 14, 20) of a drilling fluid (24) being provided with a rotatable surface seal (22) sealingly surrounding a drill string (4), the rotatable surface seal (22) being arranged to seal against a pressure difference between the surroundings and the return path (8, 14, 20), and there being arranged, at the rotating surface seal (22), a closable drilling-fluid outlet (28), the method including: arranging a pump inlet (32) from the return path (8, 14, 20) under water; connecting a pump (30) to the return path (8, 14, 20), the pump (30) being connected to a pressure pipe (34) discharging on the vessel; monitoring the drilling-fluid pressure; and controlling the pumping rate through the pump (30) to maintain a substantial

Abstract: An outer rotor of a progressive cavity pump comprising at least one inner helical rotor with Z external thread starts and at least one adapted outer rotor with a helical cavity with Z+1 internal thread starts, characterized in that at least an outer rotor (1, 3) is assembled from several concentric rotor inserts (109-113, 307-311) following closely one after another axially, with helical cavities and Z+1 internal thread starts, each rotor insert being closely surrounded by and concentrically fixed in a common rigid rotor sleeve (101, 301), and there being detachably connected to the rotor sleeve at least one removable end piece (102, 302, 303) with a principally concentric hollow extending through it axially, and that the through hollow of the end piece (102) or end pieces (302, 303) forms a gradual transition (106, 306, 312) between a principally circular cross section furthest out (135, 313, 314) and a cross section adapted to the helical cavities of the rotor inserts nearest to them (109, 307, 311).

Abstract: The invention relates to a progressive cavity pump comprising at least one inner rotor (18) with Z external threads and at least one adapted outer rotor with Z+1 internal threads, characterized by the outer rotor having radial bearings at both ends, whereas the inner rotor has a radial bearing (11) only on one side, preferably the inlet side, and there being arranged, on the same side as the bearing of the inner rotor, a conventional gear, for example a wheel gear (33 etc.), maintaining a stable ratio between the rotational speeds of the inner and outer rotors exactly equal to (Z+1)/Z.

Abstract: A system and method is described for use and return of drilling fluid/cuttings from a well, which is drilled on the ocean floor, in connection with offshore related oil production and gas production, where, from a drilling rig or drilling vessel (10), a drill stem (12) runs down into the bore hole and where a blowout preventer (BOP) is placed on said well, without mounting a riser between the rig or the vessel and said blowout preventer. A sealing and pressure-regulating device (16) is arranged on the blowout preventer (14) arranged to regulate the level of the drilling fluid, and thus the outlet pressure of the drilling fluid in said sealing and pressure-regulating device, and a pump module (18) is set up at a suitable distance adjacent said sealing and pressure-regulating device, where the pump module is arranged to pump said drilling fluid up to the ocean surface via an external return pipe.

Abstract: A riserless mud recovery system including a mud return line secured by an anchor is disclosed. Some system embodiments for drilling a well bore in an offshore location having a water surface and a subsea formation include an offshore structure positioned on a platform at a water surface, a drill string for forming the well bore suspended from the offshore structure, a drilling fluid source on the platform for supplying drilling fluid through the drill string, a suction module for collecting the drilling fluid emerging from the well bore, a return pipe coupled to the suction module, a pump for receiving the drilling fluid from the suction module and pumping the drilling fluid through the return pipe to a location at the water surface, and an anchor for securing the return pipe, where the anchor is coupled to the return pipe and the subsea formation.

Abstract: Systems and methods for drilling a well bore in a subsea formation from an offshore structure positioned on a water surface with a drill string that is suspended from the structure and includes a bottom hole assembly adapted to form a top hole portion of the well bore. A drilling fluid source on the offshore structure supplies drilling fluid through the drill string to the bottom hole assembly where the drilling fluid exits from the bottom hole assembly during drilling and returns up the well bore. A suction module is disposed at the sea floor and collects the drilling fluid emerging from the well bore. A pump module is disposed on a return line, which is in fluid communication with the suction module, at a position below the water surface and above the sea floor. The pump module is operable to receive drilling fluid from the suction module and pump the drilling fluid through the return pipe to the same offshore structure or a different offshore structure.

Abstract: A progressing cavity pump comprises at least an inner pump rotor enclosed by at least an outer pump rotor so as to collectively form one or more, in principle, separate pump cavities which, according to known geometric principles, will be moved axially through the pump upon bringing the rotors into coordinated rotation. At least two pump sections are disposed therein, each of which comprises one outer pump rotor and one adapted inner pump rotor. The outer pump rotors of all pump sections are fixedly supported and arranged along the same axis, wherein all the inner rotors are supported in fixed positions relative to a pump casing of the pump. The outer rotors of all pump sections are driven by the same motor via at least one differential arranged to allow each pump section to rotate at a mutually different rotational speed.

Abstract: A method of reducing drilling fluid pressure during subsea drilling, where drilling fluid is pumped down into a borehole and then flows back to a drilling rig via the lined and/or unlined sections of the borehole and a liner, wherein the drilling fluid pressure is controlled by pumping drilling fluid out of the liner at the seabed, and where the liner annulus above the drilling fluid is filled with a riser fluid having a density different from that of the drilling fluid.

Abstract: A method and a device for removing a hydrate plug (38) from a pipeline (16), wherein a pig (1), which is connected to an umbilical (2) extending to surface, is displaced down into the pipeline (16) until proximity of the hydrate plug (38), after which a fluid arranged with hydrate-plug-dissolving properties is pumped through the umbilical (2).