System and method of concurrently trenching, laying and burying underwater pipeline

Abstract

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.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit of priority of U.S. provisional application No. 62 / 347,226, filed Jun. 8, 2016, the contents of which are herein incorporated by reference.BACKGROUND OF THE INVENTION[0002]The present invention relates to laying underwater pipelines and, more particularly, to a system and method of concurrently trenching, laying and burying underwater pipeline.[0003]Underwater pipelines often must be buried in the sea floor in order to protect them from icebergs, anchors, nets, currents, thermal instability and the like. The present state of the art is to either dig or plow a trench before laying the pipe, lay the pipe and then back fill the trench. Alternatively, the pipe is laid first and then either using jets, mechanical cutting machines or plows, the sea floor is cut underneath the pipe and allowing the pipe to settle in the trench. Both methods are very expensive.[0004]Dredging or plowing in sand or loose material ...

AI Technical Summary

Benefits of technology

The present invention is a system for laying an underwater pipeline from a ship. The system includes a plurality of pipe support rings connected together by tension cables to form a pipe channel for guiding the underwater pipeline. A sea water pipe is also provided, which is placed underneath the pipe support rings and has a proximal end connected to a pump and a distal end with multiple nozzles. The sea water pipe is used to pump pressurized fluid into the seabed to create a trench where the underwater pipeline rests. This invention provides a faster and more efficient way to lay underwater pipelines.

Problems solved by technology

Both methods are very expensive.

Dredging or plowing in sand or loose material which is frequently experienced on continental shelves often results in slope sluffing and very high dredge quantities.

Mechanical dredging from the surface is uneconomical over 100 meters and requires dredging from the seabed which means very low production and high costs.

Plowing from the seabed has resulted in many bad experiences with many shut downs, high maintenance and therefore high cost.

Burying the pipe after it is laid is also very expensive because of the low production equipment involved.

The large jetting barges and jetting machines require several passes because they have to work around the pipe.

To date, there are no successful systems or methods for concurrently trenching, laying rigid steel pipe and burying it all in one operation for large scale pipe (8″ to 72″) from either J lay or S Lay pipe laying ships.

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