Abstract: A lifting tool for opposing twisting of generally submerged ropes. The lifting tool includes a body with a center axis, an operable lock configured to selectively limit movement of a rope connector through the body, and a structure coupled to the body and configured to couple to a hoist or crane. The lifting tool also includes at least one rudder positioned at a radial distance from the center axis to oppose rotation of the lifting tool.

Abstract: A method for estimating downhole speed and force variables at an arbitrary location of a moving drill string based on surface measurements of the same variables. The method includes a) using properties of said drill string to calculate transfer functions describing frequency-dependent amplitude and phase relations between cross combinations of said speed and force variables at the surface and downhole; b) selecting a base time period; c) measuring surface speed and force variables, conditioning the measured data by applying anti-aliasing and/or decimation filters, and storing the conditioned data, and d) calculating the downhole variables in the frequency domain by applying an integral transform, such as Fourier transform, of the surface variables, multiplying the results with said transfer functions, applying the inverse integral transform to sums of coherent terms and picking points in said base time periods to get time-delayed estimates of the dynamic speed and force variables.

Abstract: A drillstring with a bit is characterized by controllable variables of vertical and rotational speeds and response variables of axial tension force and torque, referenced to the top of the drillstring. A method of reducing or avoiding at least an axial or a torsional oscillation mode in the drillstring includes: choosing at least one oscillation mode to be controlled; selecting and monitoring a relevant controllable variable and a relevant response variable; determining the oscillation period; estimating from the response variable a dynamic component of bit speed; determining a speed pulse capable of producing a generated oscillation with amplitude substantially equal to the amplitude of the dynamic component of bit speed; and Using open-loop control to add the speed pulse to an operator set speed command when the dynamic component of bit speed has an amplitude exceeding a threshold level and an anti-phase matching a phase of the generated oscillation.

Abstract: A method for treating pipe string sections being in a set-back and being arranged in a vertical position comprises arranging a remote-controllable manipulator at least at one of the threaded portions of the pipe string sections. In addition, the method comprises providing the remote-controllable manipulator with a tool. The tool is arranged to at least clean or lubricate said threaded portion. Further, the method comprises moving the tool to a threaded portion which is to be treated and at least clean or lubricate the threaded portion.

Abstract: A method for detecting and localizing a valve leak in a piston machine having a shaft includes: attaching one or more vibration sensor to a valve block of the piston machine; measuring the vibrations from at least one of the vibration sensors; attaching a sensor to the piston machine where the sensor is designed to produce, directly or indirectly, an angular shaft position signal for the shaft; determining, directly or indirectly, an angular shaft position signal for the shaft; transforming vibration signals from the one or more vibration sensors into one envelope signal representing an instant vibration level; using the angular position signal for constructing window functions that pick the envelope signal in selected angular shaft sectors; using the window functions to find sector based averages of the vibration level; and comparing said averages with a critical ambient vibration level to detect and localize leaks in one or two valves.

Abstract: A clamping system for making and breaking threaded connections between a first tubular and a second tubular comprises a clamp assembly. The clamp assembly includes a first cam gear, a first plurality of clamp members disposed within the first cam gear, and a torque gear. Each clamp member is pivotally coupled to the torque gear. Each clamp member is configured to pivot between a withdraw position radially spaced apart from the first tubular and a gripping position engaging the first tubular. In addition, the clamping system comprises a clamp actuator. The clamp actuator includes a mounting shaft, a first clamp drive gear rotatably coupled to the mounting shaft, and a torque drive gear rotatably coupled to the mounting shaft. The first clamp drive gear is configured to rotate the first cam gear and the torque drive gear is configured to rotate the torque gear.

Abstract: A method and related device for reducing resonant vibrations and dynamic loads of cranes, where vertical motion of a pay load is controlled by a boom winch and a hoist winch. In an embodiment, the method includes determining resonance frequencies of the crane boom and pay load from inertia data of the boom and stiffness on at least the boom and hoist ropes, the resonance frequencies including a first frequency and a lower second frequency. In addition, the method includes automatically modifying the motion of the boom winch or the hoist winch to induce a damping inducing winch motion in the boom or hoist winch, by tuning a proportional integral (PI)-type boom winch speed controller or a PI-type hoist winch speed controller. The boom winch speed controller is tuned to absorb energy at the second frequency, the hoist winch speed controller is tuned to absorb energy at the first frequency.

Abstract: An apparatus for recuperation of hydraulic energy from an actuator comprises a first hydraulic machine having a first drive and a second hydraulic machine having a second drive mechanically coupled to the first drive. The first hydraulic machine is in hydraulic communication with an actuator, and the second hydraulic machine (20) is in hydraulic communication with an accumulator.

Abstract: A tow line controlling device and a method of operation of a tow line controlling device in which the tow line controlling device is positioned in a deck of a vessel. The tow line controlling device includes at least two vertical tow pins that are movable between a passive position and at least one active position, and includes a gap between two of the tow pins, and the gap is spanned by a bridge formed by the two tow pins at least when the tow pins are in one of their active positions. The tow line controlling device also includes a lower stopper that is movable between a passive position and at least one active position and is positioned between two of the tow pins.

Abstract: A system for storing one or more tubulars comprises a drilling deck including a hole offset from a wellbore centerline. In addition, the system comprises a rack unit coupled to the drilling deck and extending downward from the hole in the drilling deck. The rack unit comprises a tubular housing having a longitudinal axis, an upper end, and a lower end opposite the upper end. The rack unit also comprises a first rack disposed within the body, wherein the first rack is moveably coupled to the body.

Abstract: A heave compensating system for a marine vessel includes a hydraulic machine configured to be coupled to a load suspended from the vessel and to vary the distance between the load and the vessel in response to heaving motion of the vessel. The system further includes a second hydraulic machine in fluid communication with a hydraulic accumulator, both the first and second hydraulic machines are mechanically connected to one another and a shared electric motor, and a controller configured to control hydraulic movement of the first and second hydraulic machines and to control the supply of power to the electric motor.

Abstract: The invention relates to a sack cutting means (10) for offshore emptying of content from a package, comprising a means (11) for cutting up the package, means (21) for separating the package from its content and means (20) for removing the emptied package from the cutting means, said means (21) for separating the content at least from the package comprising means (13) for ripping the package open, one or more transporting means and a rotating drum (21) provided with openings through which the content separated from the package is allowed to leave the drum (18). Further, the sack cutting screw (11) is separated from the drum (18) and that below both the sack cutting screw (11) and the drum (17), a means (20) for collecting and transporting away the content of the sacks is arranged, said means being configured in such way that the content of the package is removed at one end, while the waste package is removed at the other end of said sack cutting means (10).

Abstract: A device for preventing a primary relief valve in a mud system from opening at a pressure lower than a nominal opening pressure includes a flow restrictor between a mud pump of the mud system and the primary relief valve. In addition, the device includes a cavity between the flow restrictor and the primary relief valve.

Abstract: A capture basket system for use below an underdeck pipehandling machine on a drill rig. The capture basket system includes a capture basket to retain a falling object such as a pipe. The capture basket is coupled to a structure of the drill rig by an energy absorber that includes an elongated element.

Abstract: An apparatus for tensioning a marine riser comprising a support for a number of actuators, where the support is connected to a vessel's structure, and where each actuator is connected to the support and to a marine riser, and where elements of the riser tensioner apparatus are enclosed.

Abstract: There is described a supporting device for one or more cables, where at least one end of each cable is connected to moving machinery, wherein the supporting device comprises two or more substantially parallel, spaced apart, flexible side bands, a plurality of interconnectors, each interconnector connecting two or more side bands, wherein the supporting device is provided with fastening means for fastening cables to at least some of the interconnectors. There is also described a method for supporting one or more cables.

Abstract: A method and a device for hoisting an item at sea with a hoisting device comprises moving the item between a plurality of different height levels. In addition, the method comprises alternately supporting the load of the item with a first hoisting rope and a second hoisting rope while moving the item between the plurality of different height levels. Further, the method comprises arranging the first hoisting rope and the second hoisting rope to extend in parallel along at least part of the distance between the item and the hoisting device. Still further, the method comprises releasably connecting the first hoisting rope to the second hoisting rope. Moreover, the method comprises suspending the second hoisting rope from a hanger when the second hoisting rope is supporting the load of the item. The method also comprises connecting the hanger to an arm of the hoisting device.

Abstract: A hydraulic clamping device comprises clamping piece supported in a structure. In addition, the clamping device comprises a hydraulic cylinder having a longitudinal axis and including a cylinder housing fixedly connected to the structure. Further, the clamping device comprises an intermediate piece axially disposed between the piston and the clamping piece. The hydraulic cylinder is adapted to exert a force along the longitudinal axis against the clamping piece.

Abstract: A device for preventing a primary relief valve in a mud system from opening at a pressure lower than a nominal opening pressure includes a flow restrictor between a mud pump of the mud system and the primary relief valve. In addition, the device includes a cavity between the flow restrictor and the primary relief valve.

Abstract: A heave compensating system for a marine vessel includes a hydraulic machine configured to be coupled to a load suspended from the vessel and to vary the distance between the load and the vessel in response to heaving motion of the vessel. The system further includes a second hydraulic machine in fluid communication with a hydraulic accumulator, both the first and second hydraulic machines are mechanically connected to one another and a shared electric motor, and a controller configured to control hydraulic movement of the first and second hydraulic machines and to control the supply of power to the electric motor.