Abstract: A rotary table for a drill string, including a stationary frame having a rotating part arranged therein, and hydraulic equipment such as hydraulic slips (wedge-shaped holding collars) and a hydraulic clamp on the rotating part, and also hydraulic power transmission between the stationary part and the rotating part. The hydraulic power transmission for each individual piece of hydraulic equipment includes a hydraulic motor (29, 30, 31) in the stationary frame (2), a hydraulic pump (17, 18, 19) in the rotating part (3), and a ring (11, 12, 13) provided with internal and external toothing, wherein the internal toothing is in driving engagement with a gearwheel (20, 21, 22) on an input shaft in the hydraulic pump and the external toothing is in driving engagement with a gearwheel (20, 21, 22) on an input shaft in the hydraulic pump and the external toothing is arranged for engageable and disengageable driving interaction with a gearwheel (24, 25, 26) on an output shaft in the hydraulic motor.

Abstract: A derrick, especially a drilling rig derrick, including a derrick structure and lifting tackle for a load, for example, a drill string, in the derrick structure.

Abstract: An apparatus for preventing pipe buckling when downwardly directed axial forces are applied to a pipeline (3) which extends from a derrick (1) down into a well bore, especially when snubbing. The apparatus comprises two sets of pipe supports (8) linked together to give a continuous chain (10), which is arranged to extend from a respective guide rail (6, 7) in the derrick (1) to the pipeline (3), and the pipe supports (8) are movably arranged in the guide rail (6, 7) parallel to the pipeline (3). The guide rail (6, 7) extends in a general U-shape with the U-bend (6c, 7c) located closest to the lower end of the derrick (1) and comprises two legs (6a, 6b, 7a, 7b), of which a first leg (6a, 7a) is arranged close to the pipeline (3) and a second leg (6b, 7b) is arranged at a greater distance from the pipeline. The pipe supports (8) are designed to be placed in the first leg (6a, 7a) when operative, and are designed to be transferred to the second leg (6b, 7b) when they are to be rendered inoperative.

Abstract: A drill floor hole comprising a through-going vertical opening in a drill floor. A pipe holder is mounted so as to be capable of vertical movement below the opening. The pipe holder is suspended in a pulley loop in a wire drive wherein a wire is attached to the drill floor, runs down and over the pulley loop and passes up to a winch.

Abstract: The invention relates to an arrangement in a pipe handling system, especially for handling pipes (4P) in connection with a derrick 1A, wherein the arrangement comprises a tower (1) and two preferably individually controlled operating arms (2a, 2b). The pipe handling system operates favorably in connection with a finger board (4) in which all fingers (4a, 4n) are pointing towards the center of the pipe handling system and especially towards a disc-shaped locking unit (4R) mounted on the top of the tower (1), and in connection with a side-step retraction system designed for use with a top drive drilling system.

Abstract: The invention relates to an arrangement in a pipe handling system, especially for handling pipes (4P) in connection with a derrick 1A, wherein the arrangement comprises a tower (1) and two preferably individually controlled operating arms (2a, 2b). The pipe handling system operates favorably in connection with a finger board (4) in which all fingers (4a, 4n) are pointing towards the center of the pipe handling system and especially towards a disc-shaped locking unit (4R) mounted on the top of the tower (1), and in connection with a side-step retraction system designed for use with a top drive drilling system.

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).