A method for burying a pipeline in a bed of a body of water which includes: making a trench with a bottom surface in a bed of a body of water via a bed working vehicle advanced in an advancing direction; advancing a floating unit in the body of water; releasing a pipeline in the body of water via a tensioner and along a lay device tilted in an adjustable manner and constrained to the floating unit; guiding the pipeline to the bottom surface of the trench via a guide vehicle advanced on the bed of the body of water; and controlling the tensioner, the floating unit, the lay device, the bed working vehicle, and the guide vehicle to minimize stress along the pipeline.

Novel tools and techniques for direct cable expansion are provided. A system includes a pump, a probe, and a coupler. The pump is coupled to a reservoir holding a fluid. The probe is in fluid communication with the pump, and is configured to introduce the fluid into a cable such that a channel is created, by the fluid, between an outer sheath of the cable and a core of the cable. The coupler is configured to attach to a cable, receive the probe, and position the probe at an interface between the outer sheath and an inner material of the cable adjacent to the outer sheath.

A system and method for moving an elongate element from a first position towards a second position against an upright structure on a vessel are disclosed. The system includes a holding element for holding the elongate element in the first position; a first sliding member pivotally connected to an end region of the holding element, and moveable along a base, ground or deck surface; a further sliding member pivotally connected to a further end region of the holding element, and moveable along the upright structure; and a hoist system operably engaged with the upright structure, the end region of the holding element and the further end region of the holding element, for drawing the holding element towards the upright structure such that the elongate element is moved towards the second position, wherein the hoist system comprises a first portion and a further portion, the first portion arranged to exert a force in a first direction and the further portion arranged to exert a force in a further direction.

A system and method for moving an elongate element from a first position towards a second position against an upright structure on a vessel are disclosed. The system includes a holding element for holding the elongate element in the first position; a first sliding member pivotally connected to an end region of the holding element, and moveable along a base, ground or deck surface; a further sliding member pivotally connected to a further end region of the holding element, and moveable along the upright structure; and a hoist system operably engaged with the upright structure, the end region of the holding element and the further end region of the holding element, for drawing the holding element towards the upright structure such that the elongate element is moved towards the second position, wherein the hoist system comprises a first portion and a further portion, the first portion arranged to exert a force in a first direction and the further portion arranged to exert a force in a further direction.

A self-propelled vehicle used to lay pipe sections within trenches located on sloped terrain, and a method for using it, including: an undercarriage carrying a vehicle chassis and capable of climbing sloped terrain; a rotating platform which can be maintained level relative to the sloped terrain; and a boom with an angled boom head, capable of using two independent winch cables to lift and position individual pipe sections having differing lengths and diameters. The vehicle may be used to sequentially lift two or more pipe sections, one at a time, and to swing and position the pipe sections in a trench, end-to-end.

A self-propelled vehicle used to lay pipe sections within trenches located on sloped terrain, and a method for using it, including: an undercarriage carrying a vehicle chassis and capable of climbing sloped terrain; a rotating platform which can be maintained level relative to the sloped terrain; and a boom with an angled boom head, capable of using two independent winch cables to lift and position individual pipe sections having differing lengths and diameters. The vehicle may be used to sequentially lift two or more pipe sections, one at a time, and to swing and position the pipe sections in a trench, end-to-end.

The present application provides a top-lock pull-out type connecting device and an immersed tube construction ship; the connecting device comprising a support member, fixedly connected to the load-bearing element and located on a side of the load-bearing element facing the borne element; a sliding member, been able to slide relative to the load-bearing element in a connection direction of the load-bearing and borne elements; an ejector rod, used to push the sliding member, fixedly connected to the borne element; a first locking member, used to lock the ejector rod, movably connected between an end of the sliding member close to the borne element and the support member, and can to be driven by the sliding member to be close to or away from the ejector rod; and a second locking member, used to lock the sliding member, and connected between an end of the sliding member away from the borne element and the load-bearing element.

The present application provides a top-lock pull-out type connecting device and an immersed tube construction ship; the connecting device comprising a support member, fixedly connected to the load-bearing element and located on a side of the load-bearing element facing the borne element; a sliding member, been able to slide relative to the load-bearing element in a connection direction of the load-bearing and borne elements; an ejector rod, used to push the sliding member, fixedly connected to the borne element; a first locking member, used to lock the ejector rod, movably connected between an end of the sliding member close to the borne element and the support member, and can to be driven by the sliding member to be close to or away from the ejector rod; and a second locking member, used to lock the sliding member, and connected between an end of the sliding member away from the borne element and the load-bearing element.

A method of installing a wave-configuration subsea riser of unbonded flexible pipe comprises lowering the riser progressively into the sea from an installation vessel while suspending an elongate clump weight in a catenary shape that comprises first and 5 second limbs extending upwardly from a conjoining bottom portion. An upper end of the first limb, at a distal end of the clump weight, is attached to the riser and an upper end of the second limb, at a proximal end of the clump weight, is suspended from a winch or crane of the vessel. While lowering the riser from the vessel, the weight load applied to the riser by the clump weight is controlled by adjusting the relative lengths of the first 0 and second limbs of the clump weight.

A method of installing a wave-configuration subsea riser of unbonded flexible pipe comprises lowering the riser progressively into the sea from an installation vessel while suspending an elongate clump weight in a catenary shape that comprises first and 5 second limbs extending upwardly from a conjoining bottom portion. An upper end of the first limb, at a distal end of the clump weight, is attached to the riser and an upper end of the second limb, at a proximal end of the clump weight, is suspended from a winch or crane of the vessel. While lowering the riser from the vessel, the weight load applied to the riser by the clump weight is controlled by adjusting the relative lengths of the first 0 and second limbs of the clump weight.