An apparatus for locating an elongate object in the seabed is disclosed. The apparatus comprises a body and a pair of jetting swords arranged on lateral sides of the elongate object to form a trench in the seabed. Chain cutters arranged on lateral sides of the elongate object cut respective parts of a trench in the seabed and are moveable relative to the body between a stowed position and a deployed position, independently of the jetting swords.

The present invention provides an improved pipeline burying apparatus that uses specially configured jetting nozzles that intake sea water surrounding the nozzle. The apparatus provides a frame supporting spaced apart left and right inclined pipe sections that are configured to be placed on opposing sides of the pipeline to be buried. Each inclined pipe section is fitted with a plurality of jetting nozzles that are positioned on one of the inclined pipe sections, in vertically spaced apart positions and in horizontally spaced apart positions. At least some of said jetting nozzles include a nozzle body having an outer surface and a main, central longitudinal fluid flow channel with a central channel axis. A fluid inlet end portion of the nozzle body has an externally threaded portion that enables connection to an internally threaded portion of a selected one of the inclined pipe sections. A discharge end portion of the nozzle body extends outwardly from an inclined pipe and the threaded portion. A plurality of lateral channels each intersect the main channel at an acute angle. In one embodiment, the main central longitudinal channel has an inlet section with an inlet section diameter, a discharge section having an outlet section diameter and a connecting section that is in between the inlet section and the outlet section.

The present invention provides a lateral and continuous measurement method for soil parameters in a soft soil field. The method mainly comprises the following measurement steps: arranging soil strength measuring apparatuses at the front end of a towing apparatus; arranging soil strain softening relationship measuring apparatuses at the bottom end of the towing apparatus; and measuring interface friction parameters between the soil and a structure. The towing apparatus actively or passively moves in a soft soil layer to ensure that the towing apparatus partially penetrates into the to-be-measured soil layer during movement; and the penetration depth of the towing apparatus is controlled by adjusting counterweight above the towing apparatus and a towing angle.

A subsea trencher for arranging at least partly into the seabed a subsea pipeline, includes at least one cart that separately carries at least one trench tool and is configured to run along the subsea pipeline. trench tool is configured to work the seabed underneath the subsea pipeline. A subsea support frame carries heavy subsea equipment connected to the trench tool for operating the trench too. When the subsea support frame is fixed to the cart, the subsea trencher is configured to load the assembled weight of the cart and subsea support frame onto the subsea pipeline as the subsea trencher runs on the subsea pipeline. When the subsea support frame is separate from the cart, the subsea support frame is configured to be suspended above the seabed or arranged beside the subsea pipeline at a distance from the subsea pipeline as the cart runs along the subsea pipeline.

The present invention provides a lateral and continuous measurement method for soil parameters in a soft soil field. The method mainly comprises the following measurement steps: arranging soil strength measuring apparatuses at the front end of a towing apparatus; arranging soil strain softening relationship measuring apparatuses at the bottom end of the towing apparatus; and measuring interface friction parameters between the soil and a structure. The towing apparatus actively or passively moves in a soft soil layer to ensure that the towing apparatus partially penetrates into the to-be-measured soil layer during movement; and the penetration depth of the towing apparatus is controlled by adjusting counterweight above the towing apparatus and a towing angle.

An apparatus for locating an elongate object in the seabed is disclosed. The apparatus comprises a body and a pair of jetting swords arranged on lateral sides of the elongate object to form a trench in the seabed. Chain cutters arranged on lateral sides of the elongate object cut respective parts of a trench in the seabed and are moveable relative to the body between a stowed position and a deployed position, independently of the jetting swords.

The present invention provides an improved pipeline burying apparatus that uses specially configured jetting nozzles that intake sea water surrounding the nozzle. The apparatus provides a frame supporting spaced apart left and right inclined pipe sections that arc configured to be placed on opposing sides of the pipeline to be buried. Each inclined pipe section is fitted with a plurality of jetting nozzles that are positioned on one of the inclined pipe sections, in vertically spaced apart positions and in horizontally spaced apart positions. At least some of said jetting nozzles include a nozzle body having an outer surface and a main, central longitudinal fluid flow channel with a central channel axis. A fluid inlet end portion of the nozzle body has an externally threaded portion that enables connection to an internally threaded portion of a selected one of the inclined pipe sections. A discharge end portion of the nozzle body extends outwardly from an inclined pipe and the threaded portion. A plurality of lateral channels each intersect the main channel at an acute angle. In one embodiment, the main central longitudinal channel has an inlet section with an inlet section diameter, a discharge section having an outlet section diameter and a connecting section that is in between the inlet section and the outlet section.

An assembly for installing a subsea cable, the assembly comprising a submersible apparatus and a submersible cable holder comprising the subsea cable, the subsea cable being connectable to the submersible apparatus through the connector for transmission of electric power and/or data to the submersible apparatus; wherein the assembly is configured to install the subsea cable while the submersible apparatus is electrically powered through said subsea cable. And a method for installing a subsea cable with a submersible apparatus, the method comprising: supplying electric power and/or transmitting data through the subsea cable to the submersible apparatus; and laying the subsea cable in a sea with the submersible apparatus.

A trencher includes a trencher body; a cable detection mechanism disposed at a front portion of the trencher body; a chain mechanism and a jet mechanism disposed in the center of a bottom portion of the trencher body; a first track mechanism and a second track mechanism, the first track mechanism being disposed on a first side of the bottom portion of the trencher body, and the second track mechanism being disposed on a second side of the bottom portion of the trencher body; and a soil discharging component disposed at a rear portion of the trencher body.

A subsea trencher for arranging at least partly into the seabed a subsea pipeline, includes at least one cart that separately carries at least one trench tool and is configured to run along the subsea pipeline. The trench tool is configured to work the seabed underneath the subsea pipeline. A subsea support frame carries heavy subsea equipment connected to the trench tool for operating the trench too. When the subsea support frame is fixed to the cart, the subsea trencher is configured to load the assembled weight of the cart and subsea support frame onto the subsea pipeline as the subsea trencher runs on the subsea pipeline. When the subsea support frame is separate from the cart, the subsea support frame is configured to be suspended above the seabed or arranged beside the subsea pipeline at a distance from the subsea pipeline as the cart runs along the subsea pipeline.