Search

EP-4263956-B1 - SYSTEM FOR EXCAVATING A TRENCH IN SUBMERGED GROUND AND ASSOCIATED EXCAVATION METHOD

EP4263956B1EP 4263956 B1EP4263956 B1EP 4263956B1EP-4263956-B1

Inventors

  • CONIGLIARO, Georges Denis
  • REYMOND, Pascal
  • JEDDAI, Ali

Dates

Publication Date
20260513
Application Date
20211215

Claims (11)

  1. Excavation system (100) for excavating a trench in ground (S) submerged in water (E), said system comprising an excavation device (110) comprising: - movement means (112) able to move said excavation device (110) over the submerged ground (S), - excavation means (116) able to be supplied with pressurized water and to excavate the submerged ground (S) using the pressurized water, said system further comprising control means (120) configured to control the movement means (112) and supply means (130) configured to supply pressurized water to the excavation means (116), characterized in that the supply means (130) comprise at least one hydrojet-type turbine (140), said at least one hydrojet-type turbine (140) being positioned on flotation means (132) suitable for positioning a water inlet (145) of said at least one hydrojet-type turbine (140) so that it is submerged in the water.
  2. Excavation system according to Claim 1, comprising at least one watercraft (150) comprising said at least one hydrojet-type turbine (140) and the flotation means (132).
  3. Excavation system according to either one of Claims 1 or 2, further comprising detection means (114) able to detect a pipeline (C) positioned on the submerged ground (S), the control means (120) being able to control the movement means (112) so as to excavate the submerged ground (S) underneath the pipeline (C).
  4. Excavation system according to any one of Claims 1 to 3, further comprising: - first obtaining means (180) able to obtain the position (PO) of the excavation device (110), - second obtaining means (190) able to obtain the depth (PR) of the water (E) at said position (PO) of the excavation device (110) by emitting and receiving acoustic waves, the control means (120) being able to control the movement means (112) as a function of the obtained position (PO) and/or of the obtained depth (PR).
  5. Excavation system according to Claim 4, wherein: - the control means (120) are positioned on a boat (B), - the second obtaining means (190) are positioned at the surface of the water (E) at the position (PO) of the excavation device (110), the second obtaining means (190) being able to transmit the obtained depth (PR) to the control means (120) via radio waves.
  6. Excavation system according to any one of Claims 1 to 5, wherein the excavation device (110) is a trencher.
  7. Excavation system according to any one of Claims 1 to 6, comprising first connection means (160) able to connect the excavation means (116) to the hydrojet-type turbine (140), these means assuming the form of a pipeline of a length of less than thirty metres.
  8. Excavation method for excavating a trench in ground submerged in water, comprising the following steps: - controlling (E112), through use of the control means (120), movement means (112) of an excavation device (110) in such a way as to move said excavation device (110) over the submerged ground (S), - supplying (E350), through use of supply means (130), pressurized water to excavation means (116) of said excavation device (110), the submerged ground (S) being excavated by the excavation means (116) using the pressurized water, the supply means (130) comprising at least one hydrojet-type turbine (140), said at least one hydrojet-type turbine (140) being positioned on flotation means (132) suitable for positioning a water inlet (145) of said at least one hydrojet-type turbine (140) so that it is submerged in the water.
  9. Excavation method according to Claim 8, further comprising the following step: - detecting (E310) a pipeline (C) positioned on the submerged ground (S), the movement means (112) being controlled in such a way that the excavation means (116) excavate the submerged ground (S) underneath the pipeline (C).
  10. Excavation method according to Claim 8 or 9, further comprising the following steps: - obtaining (E320) the position (PO) of the excavation device (110), - obtaining (E330) the depth (PR) of the water (E) at said position (PO) of the excavation device (110) by emitting and receiving acoustic waves, the controlling (E340) of the movement means (112) being performed as a function of the obtained position (PO) and/or of the obtained depth (PR).
  11. Excavation method according to any one of Claims 8 to 10, wherein: - the control means (120) are positioned on a boat (B), - the obtaining (E330) of the depth (PR) is performed by obtaining means (190) referred to as second obtaining means (190), positioned at the surface of the water (E) at the position (PO) of the excavation device (110), the method further comprising transmitting the depth measured by the second obtaining means (190) to the control means (120) via radio waves.

Description

Technical Field The present invention relates to the general field of trenching, and concerns in particular a system for digging a trench in soil immersed in water, for example marine soil. The invention applies in particular, but not exclusively, to digging a trench in soil submerged in shallow water, typically marine soil positioned less than fifty meters from the water surface (for example around a beach edge). Previous technique As is known, the burial of an underwater pipeline is carried out using a system including a digging device capable of digging trenches in the seabed. More specifically, such a digging device is capable of moving on the seabed, while digging the seabed using pressurized water, so as to dig a trench. The digging device is supplied with pressurized water by a pump positioned on the deck of a boat, with a supply pipe connecting the digging device to the pump. However, such a system is poorly suited to burying a pipeline in shallow water. Indeed, due to its size, the boat on which the pump is mounted cannot navigate in shallow waters and must therefore remain offshore. A long supply pipe must then be used, resulting in a loss of efficiency during excavation. Therefore, there is a need for a solution that allows for the efficient digging of a trench in shallow marine soil. The document CN 108 019 564 A is an example of earlier art. Description of the invention The present invention relates to a system for digging a trench in soil submerged in water, said system comprising a digging device including: means of transport capable of moving said digging device on the submerged ground, digging equipment capable of being supplied with pressurized water and of excavating submerged soil using pressurized water, said system further comprising control means configured to control the means of movement and supply means configured to supply pressurized water to the digging means, characterized in that the supply means comprise at least one hydrojet turbine, said at least one hydrojet turbine being positioned on flotation means adapted to position a water inlet of said at least one hydrojet turbine submerged in water. The high power of the hydrojet turbine allows the digging device to efficiently excavate submerged soil. Furthermore, the dimensions of the hydrojet turbine allow it to be used in shallow water. The hydrojet turbine can therefore be positioned close to the digging device, even in shallow waters, which allows for better recovery of the power of the hydrojet turbine. In a particular embodiment, the digging system includes at least one personal watercraft comprising said at least one hydrojet-type turbine and flotation means. The personal watercraft is a common piece of equipment, lightweight (approximately 300 kilograms), maneuverable, and easily transportable. Furthermore, the personal watercraft allows the hydrojet-type turbine to be positioned close to the digging device, even in shallow waters, which allows for better recovery of the power from the hydrojet type turbine. In one particular embodiment, the digging system further includes detection means capable of detecting a pipe positioned on the submerged ground, the control means being capable of controlling the means of movement so as to dig the submerged ground below the pipeline. In one particular embodiment, the digging system further comprises: the first means of obtaining the position of the digging device, of the second means of obtaining the depth of the water at said position of the digging device, by emission and reception of acoustic waves, the control means being capable of controlling the means of movement according to the position obtained and/or the depth obtained. The measurement of depth using acoustic waves, made possible by the shallow water depth, allows the control means to efficiently control the means of movement of the digging device. In a particular embodiment: The control systems are positioned on a boat. The second means of obtaining the material are positioned at the water surface at the position of the digging device. the second means of obtaining being capable of transmitting the depth obtained to the control means via radio waves. In one particular embodiment, the digging device is a trenching robot. In a particular embodiment, the digging system includes first connection means suitable for connecting the digging means to the hydrojet type turbine, taking the form of a pipeline whose length is less than thirty meters. The short length of the pipeline helps to limit power losses between the turbine and the digging equipment. The invention further relates to a method for digging a trench in soil submerged in water, comprising the following steps: control, by means of control, of means for moving a digging device, so as to move said digging device on the submerged ground, pressurized water supply, by means of supply, of means of digging said digging device, the submerged ground being excavated by the me