Abstract: A pipe-handling system includes at least two pipe-handling units arranged in a vertically displaceable manner along respective guide tracks of, respectively, first and second portions of a tower. The pipe-handling unit is provided with lower and upper rotary units spaced apart vertically on a chassis. Each of the rotary units is provided with a rotatable tong and a hanging-off device. A method is for inserting and withdrawing a pipe string in/from a borehole by the use of the pipe-handling system.

Abstract: A circulation unit and an arrangement are arranged to continuously circulate drilling fluid during drilling. A housing is provided with a center bore arranged to accommodate a portion of a pipe. The center bore includes upper and lower sealing elements. The sealing elements are provided with center openings which, by the expansion of said sealing elements, are closable or fit tightly against the pipe by the abutment of an inner sealing surface against the pipe. Each of the sealing elements is connected in a fluid-tight manner to a packing pipe which is located in the housing and which is rotatable around the center axis of the center bore. The packing pipe is surrounded by a packing assembly fitting tightly between the periphery of the packing pipe and the housing.

Abstract: A circulation unit is for an arrangement arranged to continuously circulate drilling fluid during drilling. A housing is provided with a center bore which is defined by upper and lower annular sealing elements which are rotatably supported in the housing. The sealing elements are provided with a center opening which, by the expansion of said sealing elements, is closable or fits tightly against a pipe. A gate valve in a closed state forms a fluid-tight partition between upper and lower chambers in the housing. Each of the sealing elements is connected in a fluid-tight manner to a rotatable packer pipe surrounded by a packer assembly that fits tightly against the circumference of the packer pipe and against the housing. An arrangement is for the continuous circulation of drilling fluid during drilling, including as circulation unit arranged between upper and lower rotary units.

Abstract: A circulation unit and an arrangement are arranged to continuously circulate drilling fluid during drilling. A housing is provided with a centre bore arranged to accommodate a portion of a pipe. The centre bore includes upper and lower sealing elements. The sealing elements are provided with centre openings which, by the expansion of said sealing elements, are closable or fit tightly against the pipe by the abutment of an inner sealing surface against the pipe. Each of the sealing elements is connected in a fluid-tight manner to a packing pipe which is located in the housing and which is rotatable around the centre axis of the centre bore. The packing pipe is surrounded by a packing assembly fitting, tightly between the periphery of the packing pipe and the housing.

Abstract: A circulation unit is for an arrangement arranged to continuously circulate drilling fluid during drilling. A housing is provided with a center bore which is defined by upper and lower annular sealing elements which are rotatably supported in the housing. The sealing elements are provided with a center opening which, by the expansion of said sealing elements, is closable or tits tightly against a pipe. A gate valve in a closed state forms a fluid-tight partition between upper and lower chambers in the housing. Each of the sealing elements is connected in a fluid-tight manner to a rotatable packer pipe surrounded by a packer assembly that fits tightly against the circumference of the packer pipe and against the housing. An arrangement is for the continuous circulation of drilling fluid during drilling, including as circulation unit arranged between upper and lower rotary units.

Abstract: A pipe-handling system includes at least two pipe-handling units arranged in a vertically displaceable manner along respective guide tracks of, respectively, first and second portions of a tower. The pipe-handling unit is provided with lower and upper rotary units spaced apart vertically on a chassis. Each of the rotary units is provided with a rotatable tong and a hanging-off device. A method is for inserting and withdrawing a pipe string in/from a borehole by the use of the pipe-handling system.

Abstract: A fluid pump comprising a plurality of piston cylinders (1, 2, 3, 4), wherein each individual cylinder has a piston rod (5, 6, 7, 8) with a piston (9, 10, 11, 12) arranged in the cylinder and a valve housing (13, 14, 15, 16) mounted at the end of the cylinder opposite the piston rod, and a drive arrangement for the piston rods, said drive arrangement comprising two main gearwheels (17, 18) which mesh and rotate in opposite directions. The present fluid pump is characterised in that the reciprocating motion of the piston rods (5, 6, 7, 8), which extend in pairs in opposite directions, is effected with the aid of two beams (19, 20) that are fixed to the end of the respective pair of piston rods opposite the pistons (9, 10, 11, 12), and which extend at right angles relative to the piston rods, and that the beams are connected to the main gearwheels (17 18) by shaft pins (21, 22, 22, 23) which move in pairs in guides (24) provided in the longitudinal direction of the respective beam.

Abstract: A split ball valve that may be positioned in a production string of line pipe, casing, or tubing. The split ball valve comprises a lower valve assembly and an upper valve assembly. Each of two valve doors in the lower valve assembly is connected to a pinion gear that intermeshes with racks on the upper valve assembly. The upper valve assembly can be vertically displaced relative to the lower valve assembly. A spring keeps the upper valve assembly extended away from the lower valve assembly and thus keeps the valve doors closed. When a downward force is applied to the upper valve assembly, the upper valve assembly is downwardly displaced causing the pinion gears to rotate, which opens the valve doors. The valve doors recede into cavities in the valve body. When open, the split ball valve is fully ported.

Abstract: A piston pump assembly having a single drive gear assembly associated with two adjacent pump cylinders. Each pump cylinder has a separate valve unit associated therewith. The two pump cylinders have a common piston rod having a pump piston arranged at each end. The piston pod is formed as a toothed rack and the drive gear assembly includes motor-driven gearwheels engaged with the toothed rack.

Abstract: A derrick (1) for drilling and maintenance of oil and/or gas wells comprises a portal-shaped derrick structure installed on the drilling deck, consisting of an upper traverse (2) and two spaced-apart, substantially parallel, upright derrick components (3,4) which together define a free space (5), within which a hydraulic elevator (6) connected to a drilling machine (18) for the drill string (15) is adapted to travel along stationary, upright rack rails (10). The vertically movable elevator (6), in a manner known per se, is driven by means of hydraulic motors having gears (9) that engage with the rack rails (10).