A method transports and installs a heavy subsea structure such as a subsea processing center for produced crude oil or natural gas. The method includes controlledly flooding at least one ballast tank attached to or incorporated into the structure to the extent that the structure becomes negatively buoyant at a pre-determined towing depth. The method also includes towing the negatively-buoyant structure at the towing depth by the Controlled Depth Towing Method (CDTM). After towing to the installation location, the method includes further flooding the ballast tank to lower the structure onto the seabed. At the seabed, a fluid transportation pipe of a subsea production installation may be coupled to pipework of the structure.

A safety device (20) for attaching to a pipe string (10) comprising a plurality of connected pipe sections (12). The device is configured, comprises a support structure (22) and a clamping arrangement (24) comprising a first engagement member (32) and a second engagement member (34), which clamping arrangement (24) comprises a disengaged state and an engaged state. The support structure comprises a recess (30) adapted to receive the envelope surface of the pipe section. The first engagement member and the second engagement member are arranged in different parts of the recess so that opposite sides of the pipe section are clamped between the first engagement member and the second engagement member when the clamping arrangement is in the engaged state.

A rotatable plate is configured to be coupled to a rotary table of a rig floor. The rotatable plate defines a central passage through which a tubular can be passed. Multiple arms each have a first end rotably coupled to the rotatable plate. The arms are hinged such that a distal end of the arms, away from the rotatable plate, are configured to move towards or away from the passage. Each of arms extends away from the rotatable plate towards the passage. The arms are biased away from the passage. Rollers are rotably coupled to one of the distal ends of the arms.

A rotatable plate is configured to be coupled to a rotary table of a rig floor. The rotatable plate defines a central passage through which a tubular can be passed. Multiple arms each have a first end rotably coupled to the rotatable plate. The arms are hinged such that a distal end of the arms, away from the rotatable plate, are configured to move towards or away from the passage. Each of arms extends away from the rotatable plate towards the passage. The arms are biased away from the passage. Rollers are rotably coupled to one of the distal ends of the arms.

A coiled tubing system includes an injector assembly configured to receive and longitudinally move coiled tubing through the injector assembly, a well control stack operatively coupled to the injector assembly and configured to receive the coiled tubing from the injector assembly, and a snap arrestor including one or more wheels configured to rotate as the coiled tubing moves longitudinally, a tachometer that measures rotations per minute (RPM), and a microprocessor that receives and converts the RPM into a real-time measured linear speed of the coiled tubing. When the real-time measured linear speed of the coiled tubing exceeds a predetermined linear speed threshold, a command signal is sent to the injector assembly to grippingly engage the coiled tubing and thereby cease longitudinal movement of the coiled tubing.

A coiled tubing system includes an injector assembly configured to receive and longitudinally move coiled tubing through the injector assembly, a well control stack operatively coupled to the injector assembly and configured to receive the coiled tubing from the injector assembly, and a snap arrestor including one or more wheels configured to rotate as the coiled tubing moves longitudinally, a tachometer that measures rotations per minute (RPM), and a microprocessor that receives and converts the RPM into a real-time measured linear speed of the coiled tubing. When the real-time measured linear speed of the coiled tubing exceeds a predetermined linear speed threshold, a command signal is sent to the injector assembly to grippingly engage the coiled tubing and thereby cease longitudinal movement of the coiled tubing.

A fall arrest safety system for overhead rotating tools includes a tether ring assembly having an inner ring and an outer ring. The inner ring clamps onto the rotating tubular and the outer ring is tethered to the top drive unit. In the event of a disconnect, the tethered assembly holds the load.

A fall arrest safety system for overhead rotating tools includes a tether ring assembly having an inner ring and an outer ring. The inner ring clamps onto the rotating tubular and the outer ring is tethered to the top drive unit. In the event of a disconnect, the tethered assembly holds the load.

A security device placed at a wellhead over a blowout preventer valve, which can be activated to catch a cable and/or a string of pipes upon a cut event or accident, preventing the fall of the same into the well, which includes: an upper horizontal plate and lower horizontal plate, vertically aligned, each having a circular central orifice for the passing of a string of pipes and/or a cable, and a cutout on the front part thereof, located between its front edge and the circular orifice; lateral support device, located between the upper and lower plates, that connect the plates together, delimiting an aperture at the front part of the device that together with the cutouts on the upper and lower plates form a front passage toward the inside of the device; at least two clamps driven by corresponding hydraulic cylinders, which are arranged at an acute angle with the vertical axis of the device; and a movable vertical plate arranged on the front part of the device between the lateral support means, pivotally connected by one of its sides to the upper and lower plates. The movable vertical plate, in a first position, allows for the horizontal passing of a string of pipes and/or cables through the front passage to a location at the center of the device, and in a second position, the movable vertical plate blocks the front passage. In a first position the clamps allow for vertical movement of the string of pipes and or cables and in a second position the clamps block the movement of the same.

A security device placed at a wellhead over a blowout preventer valve, which can be activated to catch a cable and/or a string of pipes upon a cut event or accident, preventing the fall of the same into the well, which includes: an upper horizontal plate and lower horizontal plate, vertically aligned, each having a circular central orifice for the passing of a string of pipes and/or a cable, and a cutout on the front part thereof, located between its front edge and the circular orifice; lateral support device, located between the upper and lower plates, that connect the plates together, delimiting an aperture at the front part of the device that together with the cutouts on the upper and lower plates form a front passage toward the inside of the device; at least two clamps driven by corresponding hydraulic cylinders, which are arranged at an acute angle with the vertical axis of the device; and a movable vertical plate arranged on the front part of the device between the lateral support means, pivotally connected by one of its sides to the upper and lower plates. The movable vertical plate, in a first position, allows for the horizontal passing of a string of pipes and/or cables through the front passage to a location at the center of the device, and in a second position, the movable vertical plate blocks the front passage. In a first position the clamps allow for vertical movement of the string of pipes and or cables and in a second position the clamps block the movement of the same.