A jetting system for an undersea trencher has jetting conduits extending aftward of its trench-cutting jetting swords. Jetting conduit nozzles direct liquid radially from their jetting conduits into the trench after the trench is excavated by the jetting sword cutting nozzles. The jetting conduits direct sufficient liquid into the trench to maintain the mix of trenched soil and water in the trench along the length of the conduits at not more than a super-critical density, extending the distance in which the product being laid in the trench is able to descend in the trench and increasing the likelihood that the product will be buried at the intended trench depth.

An underwater trenching apparatus and pumping apparatus and method of operating an underwater trenching apparatus is disclosed. The underwater trenching apparatus and pumping apparatus includes: first and second pumps and a trench-cutting jetting tool with first and second sections, the first pump having an inlet for fluid connection with a source of water and an outlet fluidly connected to the first section of the jetting tool, the second pump having an inlet for fluid connection with a source of water and an outlet fluidly connected to the second section of the jetting tool, wherein the outlet of the first pump is fluidly connected to the inlet of the second pump by valve means that is operable to divert at least a portion of an outlet flow of the first pump to the inlet of the second pump.

A trenching assembly lays a continuous pipeline in a trench dug in a bed with uneven bathymetry, the trenching assembly including a trench digging device having a main body; at least four ground contact units, each unit having a height adjustment device, to position each ground contact unit with respect to the main body independently. A trench cutting tool digs in the bed includes a cutting depth adjustment device, for positioning the cutting tool with respect to the main body. A detection device detects bed bathymetry. A control device simultaneously allows cooperation between the detection device, the height adjustment device of each ground contact unit, and the cutting depth adjustment device. A command device cooperates with the control device to adjustment each ground contact unit and the cutting depth adjustment device, to obtain a trench having a height difference lower than a predefined tolerance and a predetermined burial depth.

A jetting system for an undersea trencher has jetting conduits extending onward of its trench-cutting jetting swords. Jetting conduit nozzles direct liquid radially from their jetting conduits into the trench after the trench is excavated by the jetting sword cutting nozzles. The jetting conduits direct sufficient liquid into the trench to maintain the mix of trenched soil and water in the trench along the length of the conduits at not more than a super-critical density, extending the distance in which the product being laid in the trench is able to descend in the trench and increasing the likelihood that the product will be buried at the intended trench depth.

A hand held supersonic air knife with a supersonic variable flow nozzle yields a continuously variable power mass flow rate (CFM) and pressure over a selectable power range, responsive to rotations of the nozzle exterior sleeve or outer nozzle member. The maximum power position identified as one end position and a second end position as the lowest power. The exterior sleeve can be rotated to any axial or circumferential position between start (low) and end (high). The result will be an intermediate power position. Any intermediate position will also be a supersonic nozzle of varying parameters between the start and end positions. Thus, a variable flow supersonic nozzle is provided by the manual sleeve rotation by an operator or a remotely controlled positioning of the sleeve.

Subsea blower device comprising at least one nozzle, at least one propel arranged to provide the nozzle with water, further comprising a chassis with belts for movement of the device along the seafloor. The device typically has at least one arm pivotally attached to the chassis so that the position of the arm in relation to a horizontal plane is adjustable, while the nozzle is attached to the arm.

A system and method for laying an underwater pipeline is provided. The present invention includes a plurality of pipe support rings connected together by tension cables. The tension cables are secured to a S or J laying ship by a winch. The plurality of pipe support rings form a pipe channel sized to guide the underwater pipeline. The present invention further includes a sea water pipe having a distal portion and a proximal end. The proximal end is fluidly connected with a pump on board the ship. The distal end includes a plurality of nozzles. The sea water pipe is disposed underneath the plurality of pipe support rings. The underwater pipeline is fed through the plurality of pipe support rings while the nozzles form a trench on a sea bed.

A jetting system for an undersea trencher has jetting conduits extending aftward of its trench-cutting jetting swords. Jetting conduit nozzles direct liquid radially from their jetting conduits into the trench after the trench is excavated by the jetting sword cutting nozzles. The jetting conduits direct sufficient liquid into the trench to maintain the mix of trenched soil and water in the trench along the length of the conduits at not more than a super-critical density.

An apparatus for forming a trench along the bed of a body of water for burying a line lying along such bed including a support structure designed to straddle such line, means for propelling such structure straddling such line and means disposed on such structure including a pair of transversely spaced excavator devices cooperable in forming a trench along the bed of such body of water for receiving such line, each provided with a set of circumferentially spaced, pressurized fluid ejecting nozzles, rotatable about an axis.

A system to generate pressurized air for hydro-excavation includes an exhaust silencer configured to hold water and an exhaust manifold disposed through the silencer, where the exhaust manifold is configured to be in fluid communication with an internal combustion engine in order to receive exhaust gases to heat the exhaust silencer. In addition, the system includes a steam turbine configured to be driven by steam generated in the exhaust silencer, a primary steam line secured proximate to an upper end of the silencer to connect to the steam turbine, and an air compressor driven by the steam turbine to generate pressurized air. A secondary steam line is in fluid communication with the primary steam line and the air compressor to generate a mixture of the steam and pressurized air for use in hydro-excavation. The system also includes a vacuum pump driven by the internal combustion engine, a suction hose configured to excavate materials using a vacuum pressure generated by the vacuum pump, a debris tank in fluid communication with the suction hose, and a nozzle configured to receive and discharge the mixture of the steam and pressurized air in order to break up soil.