Seabed ditching device with high geological adaptability
By combining buoyancy adjustment, spiral propulsion, and jetting devices, the problem of insufficient adaptability of traditional subsea trenching equipment under different seabed conditions has been solved, achieving efficient and safe subsea trench excavation.
Patent Information
- Application Number
- CN202520172891.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-26
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2035-01-26
AI Technical Summary
Traditional underwater trenching equipment cannot automatically adjust buoyancy, making it difficult to adapt to seabed mud and sand of varying hardness, resulting in high operational risks and limited adaptability.
A seabed trenching device was designed, comprising a buoyancy adjustment device, a propeller, and a jetting device. The buoyancy adjustment device adjusts the buoyancy of the device, the propeller provides the mobility, and the jetting device forms trenches with high-pressure liquid, thus enabling adaptation to different seabed conditions.
It improves the operational efficiency and safety of the seabed trenching device, reduces costs and risks, and has a wider range of adaptability, enabling it to excavate trenches of different depths under different seabed conditions.
Smart Images
Figure CN223867324U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of underwater operation equipment, specifically relating to an underwater trenching device with strong geological adaptability. Background Technology
[0002] When laying submarine cables, it is necessary to dig corresponding cable trenches. Currently, traditional submarine trenching equipment has too many limitations when performing trenching operations. It cannot automatically adjust the buoyancy of the trenching equipment. The hardness of seabed mud and sand is complex. When the trenching equipment is in soft mud, there is a great risk of getting stuck in the mud. When it is in hard mud, greater pressure on the ground is required. Its adaptability to digging trenches of different depths in different locations is limited. Utility Model Content
[0003] The purpose of this invention is to overcome the shortcomings of the aforementioned background technology and provide a submarine trenching device with good seabed adaptability and strong geological adaptability.
[0004] The technical solution adopted by this utility model is: a seabed trenching device with strong geological adaptability, including a main frame, a buoyancy adjustment device is set at the top of the main frame, a spiral propeller is set on both sides of the main frame, and two jet devices are symmetrically set at the bottom of the main frame.
[0005] The buoyancy adjustment device is used to adjust the buoyancy of the seabed trenching device on the seabed, the propeller is used to drive the seabed trenching device to move on the seabed, and the two jetting devices are used to dig trenches of corresponding depths at corresponding positions on the seabed by jetting high-pressure liquid.
[0006] Furthermore, the buoyancy adjustment device is provided in four parts. The four buoyancy adjustment devices are used to adjust the buoyancy of the four sides of the submarine cable laying robot respectively. The buoyancy adjustment device includes an oil bladder and a pressure tank. The oil bladder and the pressure tank are connected by a connecting pipe. The pressure tank stores a low-density oil medium. The buoyancy is adjusted by controlling the inflow and outflow of the oil medium in the pressure tank to the oil bladder.
[0007] Furthermore, the screw propeller is a cylindrical structure with external helical blades. The two ends of the screw propeller are fixedly connected to the main frame through mounting brackets. The screw propeller is driven by a motor to rotate forward or backward, thereby propelling the equipment forward.
[0008] Furthermore, the spraying device includes a high-pressure spray pump and a spraying arm. The high-pressure spray pump is connected to the inside of the spraying arm through a liquid pipeline, and the spraying arm is provided with a plurality of nozzles.
[0009] The high-pressure jet pump is used to compress seawater into high-pressure liquid. The high-pressure liquid flows through the liquid pipeline to the inside of the jet arm and is ejected from the nozzle to shear the seabed and form a trench of corresponding depth. The depth of the trench is controlled by adjusting the length of the jet arm.
[0010] Furthermore, the spray arm includes a fixed base, a fixed spray arm, a telescopic spray arm, and a length adjustment mechanism. The fixed base is hinged to the liquid pipeline. The fixed ends of both the fixed spray arm and the telescopic spray arm are mounted on the fixed base. The length of the telescopic spray arm is greater than the length of the fixed spray arm. The fixed base has a channel connecting the liquid pipeline to the fixed spray arm and the telescopic spray arm. The plurality of nozzles are disposed on the fixed spray arm and the telescopic spray arm. One end of the length adjustment mechanism is connected to the telescopic end of the telescopic spray arm, and the other end is connected to the fixed base.
[0011] Furthermore, the fixed spray arm includes several fixed spray pipes of different lengths, which are arranged in order from shortest to longest. The fixed spray pipes are located in the same vertical plane and are arranged at an angle, with the shortest fixed spray pipe located at the bottom. The nozzle is located at the bottom of the fixed spray pipes.
[0012] Furthermore, the telescopic spray arm includes several telescopic spray pipes arranged side by side and several fixed pipes arranged coaxially. The nozzle is disposed at the bottom of several telescopic spray pipes. One end of the fixed pipe is connected to a fixed seat, and the other end of the fixed pipe is sleeved inside the telescopic spray pipe and in sealed contact with the inner wall of the telescopic spray pipe. The telescopic spray pipe includes a fixed spray section and a telescopic spray section. The fixed spray section is disposed at the end of the telescopic spray section. The fixed spray section is provided with a mounting seat connected to one end of a length adjustment mechanism. The length adjustment mechanism can adjust the length of the telescopic spray section relative to the fixed pipe, thereby realizing the adjustment of the length of the telescopic spray arm.
[0013] Furthermore, a sealing ring is provided on the outer wall of the other end of the fixed tube, and the other end of the fixed tube is in sealed contact with the inner wall of the telescopic nozzle through the sealing ring.
[0014] Furthermore, the fixed base includes a fixed plate and a triangular, hollow hinge section. One end of the hinge section is hinged to a liquid pipeline, and the ends of the fixed spray arm, telescopic spray arm, and fixed plate are all connected to the other end of the hinge section. The sides of the fixed spray arm and telescopic spray arm are connected to the sides of the fixed plate.
[0015] Furthermore, the spraying device also includes an angle adjustment mechanism, which is used to adjust the angle of the spraying arm. One end of the angle adjustment mechanism is connected to the main frame, and the other end is connected to the fixed seat of the spraying arm.
[0016] Furthermore, there are two high-pressure injection pumps, which are connected to the inside of the injection arm through the same liquid pipeline.
[0017] Furthermore, the main frame is equipped with an electric thruster for adjusting the relative position of the submarine cable laying robot and the submarine cable. The electric thruster includes side thrusters mounted on four columns of the main frame and a thruster mounted at the tail of the submarine cable laying robot. The axes of the four side thrusters form a certain angle with the direction of travel of the submarine cable laying robot, and the axis of the tail thruster is parallel to the direction of travel of the submarine cable laying robot.
[0018] Furthermore, the main frame is equipped with a detection component for detecting the relative position of the submarine cable laying robot and the submarine cable. The detection component includes an external sensor and an internal sensor. The internal sensor is fixed to the main frame, and the external sensor is mounted on the main frame via a mounting bracket. The end of the mounting bracket is hinged to the edge of the main frame, and the mounting bracket can rotate 90 degrees around the hinge point with the main frame. When the mounting bracket is parallel to the horizontal plane, the external sensor is parallel to the sea level.
[0019] The beneficial effects of this utility model are as follows:
[0020] This utility model arranges buoyancy adjustment devices, propellers, jetting devices, electric propellers, detection components and other equipment on the trenching device. Through the cooperation of various devices, the entire trenching device has the versatility to operate at different trenching depths and at different seabed sediment hardness, thereby improving operation efficiency and safety, and reducing costs and risks.
[0021] The spraying device on this trenching device can dig trenches of different depths according to needs, making it more versatile.
[0022] The buoyancy adjustment device on the trenching device of this invention can adjust the buoyancy (or weight) of the trenching device in the sea according to the different shear forces of the mud surface on the seabed, thereby reducing the risk of the trenching device getting stuck in the mud.
[0023] The auger propeller on this trenching device can travel on mud surfaces with different shear forces on the seabed, making it more widely applicable.
[0024] The spraying arm of this utility model trenching device features both fixed and telescopic spraying arm structures, allowing for adjustable length and deeper trenching. It can also dig trenches of varying depths to meet different needs, making it more versatile. Furthermore, the spraying arm can utilize multiple nozzles for trenching, with longer extensions providing more nozzles and higher efficiency. The two spraying devices are symmetrically arranged on the main frame, and their four high-pressure pumps ensure the symmetry of the entire trenching device, reducing vibration and swaying during operation, thus enhancing safety during operation and movement.
[0025] The electric propellers on the trenching device of this utility model are symmetrically installed on the frame, which can reduce the shaking of the trenching device caused by unbalanced force due to vibration during operation, and enhance safety during operation and travel. Attached Figure Description
[0026] Figure 1 This is a three-dimensional structural diagram of the present invention.
[0027] Figure 2 This is a schematic diagram of the connection between the two spraying devices of this utility model.
[0028] Figure 3 This is a schematic diagram of the spray arm of this utility model extended to its longest position.
[0029] Figure 4 This is a schematic diagram of the spray arm of this utility model retracted to its shortest position.
[0030] Figure 5 This is a partial schematic diagram of the telescopic spray arm of the present invention.
[0031] Figure 6 This is another partial schematic diagram of the telescopic spray arm of the present invention.
[0032] Figure 7 This is a schematic diagram of the arrangement of the electric propulsion device of this utility model.
[0033] Figure 8 This is a schematic diagram of the detection component of this utility model.
[0034] In the diagram, 1-main frame; 2-buoyancy adjustment device; 2.1-oil bladder; 2.2-pressure tank;
[0035] 3-Screw propeller; 3.1-Mounting bracket; 3.2-Motor housing; 4-Buoyancy material; 5-Injection device; 5.1-High-pressure injection pump; 5.2-Injection arm; 5.3-Liquid pipeline; 5.4-Nozzle; 5.5-Fixed base; 5.6-Fixed spray arm; 5.6.1-Fixed nozzle; 5.7-Telescopic spray arm; 5.7.1-Telescopic nozzle; 5.7.2-Fixed pipe; 5.7.3-Fixed injection section; 5.7.4-Telescopic injection section; 5.7.5-Mounting base; 5.7.6-Sealing ring; 5.8-Length adjustment mechanism; 5.9-Angle adjustment mechanism; 6-Electric propeller; 7-Detection component; 7.1-External sensor; 7.2-Internal sensor; 7.3-Mounting bracket. Detailed Implementation
[0036] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. It should be noted that these descriptions are for the purpose of aiding understanding of this utility model, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.
[0037] like Figure 1-8 As shown, this utility model provides a highly geologically adaptable seabed trenching device, including a main frame 1. The top of the main frame 1 is equipped with an underwater buoyancy adjustment device 2, and the two sides of the main frame 1 are respectively equipped with propellers 3. Two jetting devices 5 are symmetrically arranged at the bottom of the main frame 1. The buoyancy adjustment device 2 is used to adjust the buoyancy of the seabed trenching device to adapt to the equipment's movement and attitude stability control requirements during trenching operations under different hardness bottom sediments. The propellers 3 are used to drive the seabed trenching device to move on the seabed. The two jetting devices 5 are used to dig trenches of corresponding depths at corresponding positions on the seabed by spraying high-pressure liquid.
[0038] In some embodiments, the buoyancy adjustment device 2 is provided in four parts, each including an oil bladder 2.1 and a pressure tank 2.2 arranged vertically. The oil bladder 2.1 and the pressure tank 2.2 are connected by a connecting pipe. The pressure tank 2.2 stores a low-density oil medium. By controlling the inflow and outflow of the oil medium from the pressure tank to the oil bladder 2.1, the volume of the bladder is changed to provide different buoyancy requirements. The weight of the trenching device in the sea can be adjusted according to the different shear forces of the mud surface on the seabed, reducing the risk of the trenching device sinking into the mud. A buoyancy material 4 is also provided above the buoyancy adjustment device 2. The buoyancy material, in conjunction with the buoyancy adjustment device, ensures the buoyancy of the seabed trenching device on the seabed.
[0039] In some embodiments, the helical propeller 3 comprises two propellers, each a cylindrical structure with external helical blades. The two propellers 3 are symmetrically arranged on both sides of the bottom of the main frame 1, and their ends are fixedly connected to the main frame via mounting brackets 3.1. The helical propellers enhance the adaptability of the trenching device to different shear forces on the seabed, allowing it to navigate both soft and hard mud surfaces. Driven by a motor in the motor housing 3.2, the helical propellers 3 can operate in both forward and reverse directions, ensuring the trenching device can move forward and backward, resulting in higher trenching efficiency and greater safety. Simultaneously, they allow for horizontal turning on the seabed, increasing the flexibility of the trenching device's horizontal movement.
[0040] In some embodiments, the spraying device 5 includes a high-pressure spray pump 5.1 and a spraying arm 5.2. Two high-pressure spray pumps 5.2 are provided and spaced apart on the main frame 1. Providing two high-pressure spray pumps can improve the efficiency of seawater compression and increase reliability. The four high-pressure spray pumps on both sides can also ensure the symmetry of the entire trenching device center, reducing the shaking caused by unbalanced forces during operation due to vibration, and enhancing safety during operation and movement. The high-pressure spray pump is a centrifugal electric pump. The high-pressure spray pump 5.2 is connected to the inside of the spraying arm 5.2 through a liquid pipeline 5.3. The spraying arm 5.2 is provided with several nozzles 5.4; for example... Figure 5 As shown, a connecting pipe 5.3.1 is provided between the two spray arms 5.2, which connects the liquid pipelines of the two spray devices to improve structural stability. The high-pressure jet pump 5.2 is used to compress seawater into high-pressure liquid. The high-pressure liquid flows through the liquid pipeline 5.3 into the interior of the spray arm 5.2 and is ejected from the nozzle 5.4 to shear the seabed and form the trench. The depth of the trench is controlled by adjusting the length of the spray arm 5.2.
[0041] It is understood that the spray arm 5.2 includes a fixed base 5.5, a fixed spray arm 5.6, a telescopic spray arm 5.7, a length adjustment mechanism 5.8, and an angle adjustment mechanism 5.9. The fixed base 5.5 is hinged to the liquid pipeline 5.3. The fixed ends of the fixed spray arm 5.6 and the telescopic spray arm 5.7 are both mounted on the fixed base 5.5. The length of the telescopic spray arm 5.7 is greater than the length of the fixed spray arm 5.6. The fixed base 5.5 has a channel connecting the liquid pipeline to the fixed spray arm 5.6 and the telescopic spray arm 5.7. The plurality of nozzles 5.4 are disposed on the fixed spray arm. On 5.6 and the telescopic spray arm 5.7, the axes of several nozzles 5.4 are aligned. One end of the length adjustment mechanism 5.8 is connected to the telescopic end of the telescopic spray arm 5.7, and the other end is connected to the fixed base 5.5. The length of the spray arm is adjusted by adjusting the length of the telescopic spray arm through the length adjustment mechanism 5.8. The angle adjustment mechanism 5.9 is used to adjust the angle between the spray arm 5.2 and the horizontal line. The angle adjustment device 5.9 is a telescopic adjustable hydraulic cylinder. One end of the angle adjustment mechanism 5.9 is connected to the main frame 1, and the other end is connected to the fixed base 5.5.
[0042] It is understood that the fixed spray arm 5.6 includes several fixed spray pipes 5.6.1 of different lengths, which are arranged in order from shortest to longest. The fixed spray pipes 5.6.1 are located in the same vertical plane and are arranged at an angle. The shortest fixed spray pipe is located at the bottom. The nozzle is located at the bottom of the fixed spray pipes and is not covered by the corresponding shorter fixed spray pipe. The telescopic spray arm 5.7 includes several telescopic spray pipes 5.7.1 arranged side by side and several fixed pipes 5.7.2 arranged coaxially. The nozzle 5.4 is disposed at the bottom of the telescopic spray pipes 5.7.1. One end of the fixed pipe 5.7.2 is connected to the fixed seat 5.5, and the other end is sleeved inside the telescopic spray pipe 5.7.1. The outer wall of the other end of the fixed pipe 5.7.2 is provided with a sealing ring 5.7.6, which seals against the inner wall of the telescopic spray pipe 5.7.1. The telescopic spray pipe 5.7.1 includes a fixed spray section 5.7.3 and a telescopic spray section 5.7.4. The fixed spray section 5.7.3 is disposed at the end of the telescopic spray section 5.7.4. The fixed spray section 5.7.3 is provided with a mounting seat 5.7.5 connected to one end of a length adjustment mechanism. The length adjustment mechanism 5.8 can adjust the length of the telescopic spray arm 5.7 relative to the fixed pipe 5.7.2, thereby adjusting the length of the telescopic spray arm 5.7. The sealing ring 5.7.6 on the fixed tube 5.7.2 ensures that after adjusting the telescopic spray section (shortening the spray arm length), the corresponding nozzle is sealed (that is, the nozzle is separated from the inside of the fixed tube), so that the high-pressure liquid does not spray out from the nozzle 5.4.1 at the shortened part, but only from the unsealed nozzle 5.4.2, thus reducing the number of nozzles (adjusting the length of the spray arm).
[0043] It is understood that the fixed base 5.5 includes a fixed plate 5.5.2 and a triangular and hollow hinge section 5.5.1. One end of the hinge section 5.5.1 is hinged to the liquid pipeline 5.3. The ends of the fixed spray arm 5.6, the telescopic spray arm 5.7 and the fixed plate 5.5.2 are all connected to the other end of the hinge section 5.5.1. The sides of the fixed spray arm 5.6 and the telescopic spray arm 5.7 are connected to the sides of the fixed plate 5.5.2.
[0044] In some embodiments, the device further includes an electric thruster 6 and a detection component 7, both integrated onto the main frame 1. The detection component 7 is used to detect the position of the seabed trenching device on the seabed, and the electric thruster 6 is used to adjust the position of the seabed trenching device on the seabed based on the detection results of the detection component. Figure 7As shown, the electric thrusters 6 are respectively located at the four corners of the main frame (on the sides of the four columns) and at the tail of the seabed trenching device. The electric thrusters adopt a paddle structure. The axes of the electric thrusters (6.1-6.4) located at the four corners of the main frame form a 45° angle with the direction of travel of the seabed trenching device, while the axes of the electric thrusters (6.5, 6.6) located at the tail of the seabed trenching device are parallel to the direction of travel of the seabed trenching device. This combination arrangement of thrusters can provide power to the trenching device in six dimensions, ensuring that the trenching device can move in six dimensions. The detection component 7 is arranged at the head of the trenching device, such as... Figure 8 As shown, it includes an external sensor 7.1 and an internal sensor 7.2. The internal sensor 7.2 is fixed to the main frame 1, and the external sensor 7.1 is mounted on the main frame 1 via a mounting bracket 7.3. The end of the mounting bracket 7.3 is hinged to the edge of the main frame 1. A retractable hydraulic cylinder 7.4 is provided between the mounting bracket 7.3 and the main frame 1. The hydraulic cylinder can drive the mounting bracket to rotate 90 degrees around its hinge point with the main frame. When the mounting bracket is parallel to the main frame, the external sensor 7.1 faces the seabed. Positioning is achieved through the detection components using a combination of internal and external sensors. Compared to a single internal or single external sensor, this invention offers higher positioning efficiency and greater accuracy.
[0045] In some embodiments, the adjustment and control of the buoyancy adjustment device 2, the propeller 3, the two jet devices 5, the electric propeller 6, and the detection component 7 are controlled by a control unit to realize the trenching operation. The control unit can be a conventional control system external to equipment such as ships. The specific process is as follows:
[0046] The buoyancy adjustment device 2 expands the oil bladder 2.1 to the set volume according to the set value to ensure buoyancy in the water.
[0047] The trenching device flies to its destination in the water using six electric propulsion units.
[0048] The hydraulic cylinder 7.4 in the detection component 7 is activated, causing the mounting frame 7.3 to be in a horizontal position. The internal sensor 7.2 and the external sensor 7.1 are positioned to determine the specific location and direction of the trench. The trenching device adjusts its posture according to the trenching location and direction until it is consistent with the posture during the trenching operation.
[0049] Electric thrusters group 6 stopped working, propeller thruster 3 started, and high-pressure jet pump 5.1 started.
[0050] The angle adjustment mechanism 5.9 of the spray arm 5.2 is activated until the entire spray arm 5.2 is rotated to the set angle. Then the length adjustment mechanism 5.8 is activated, and the spray arm 5.2 is extended to the set position, that is, positioned at the required digging depth.
[0051] After the trenching device reaches the seabed mud surface, the buoyancy of the entire trenching device in the water is adjusted according to the hardness of the seabed mud and sand to ensure operational efficiency.
[0052] Adjust the propeller speed according to the hardness of the seabed sediment to ensure the speed during trenching operations and improve work efficiency.
[0053] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Contents not described in detail in this specification belong to prior art known to those skilled in the art.
Claims
1. A highly geologically adaptable subsea trenching device, characterized in that: It includes a main frame (1), an underwater buoyancy adjustment device (2) is provided on the top of the main frame, a spiral propeller (3) is provided on both sides of the main frame (1), and two jet devices (5) are symmetrically provided at the bottom of the main frame (1); The buoyancy adjustment device (2) is used to adjust the buoyancy of the seabed trenching device on the seabed, the propeller (3) is used to drive the seabed trenching device to move on the seabed, and the two jetting devices (5) are used to shear the seabed soil at corresponding positions on the seabed by jetting high-pressure liquid to form trenches of corresponding depths.
2. The geologically adaptable subsea trenching device according to claim 1, characterized in that: The buoyancy adjustment device (2) is provided in four parts. The four buoyancy adjustment devices are used to adjust the buoyancy of the four sides of the submarine cable laying robot respectively. The buoyancy adjustment device (2) includes an oil bladder (2.1) and a pressure tank (2.2). The oil bladder (2.1) and the pressure tank (2.2) are connected by a connecting pipe. The pressure tank (2.2) stores a low-density oil medium. The buoyancy is adjusted by controlling the inflow and outflow of the oil medium in the pressure tank (2.2) to the oil bladder (2.1).
3. The geologically adaptable subsea trenching device according to claim 1, characterized in that: The spiral propeller (3) is a cylindrical structure with spiral blades on the outside. The two ends of the spiral propeller (3) are fixedly connected to the main frame (1) through the mounting bracket (3.1). The spiral propeller (3) is driven by a motor to rotate forward or backward.
4. The geologically adaptable subsea trenching device according to claim 1, characterized in that: The spraying device (5) includes a high-pressure spray pump (5.1) and a spraying arm (5.2). The high-pressure spray pump (5.1) is connected to the inside of the spraying arm (5.2) through a liquid pipeline (5.3). The spraying arm (5.2) is provided with a plurality of nozzles (5.4). The high-pressure jet pump (5.1) is used to compress seawater into high-pressure liquid. The high-pressure liquid flows through the liquid pipeline (5.3) to the inside of the jet arm (5.2) and is ejected from the nozzle (5.4) to shear the seabed and form the trench. The depth of the trench is controlled by adjusting the length of the jet arm (5.2).
5. The geologically adaptable subsea trenching device according to claim 4, characterized in that: The spray arm (5.2) includes a fixed base (5.5), a fixed spray arm (5.6), a telescopic spray arm (5.7), a length adjustment mechanism (5.8), and an angle adjustment mechanism (5.9). The length adjustment mechanism (5.8) is used to adjust the length of the spray arm, and the angle adjustment mechanism (5.9) is used to adjust the angle of the spray arm. The fixed base (5.5) is hinged to the liquid pipeline. The fixed ends of both the fixed spray arm (5.6) and the telescopic spray arm (5.7) are mounted on the fixed base (5.5). The telescopic spray arm (5.7)... The length of the fixed spray arm (5.6) is greater than the length of the fixed spray arm (5.6). The fixed base (5.5) is provided with a channel connecting the liquid pipe to the fixed spray arm (5.6) and the telescopic spray arm (5.7). The plurality of nozzles are arranged on the fixed spray arm (5.6) and the telescopic spray arm (5.7). One end of the length adjustment mechanism (5.8) is connected to the telescopic end of the telescopic spray arm (5.7) and the other end is connected to the fixed base (5.5). One end of the angle adjustment mechanism (5.9) is connected to the main frame (1) and the other end is connected to the fixed base (5.5).
6. The geologically adaptable subsea trenching device according to claim 5, characterized in that: The fixed spray arm (5.6) includes several fixed nozzles (5.6.1) of different lengths. The fixed nozzles (5.6.1) are arranged in order from shortest to longest. The fixed nozzles (5.6.1) are located in the same vertical plane and are arranged at an angle. The shortest fixed nozzle is located at the bottom. The nozzle (5.4) is located at the bottom of the fixed nozzles (5.6.1).
7. The geologically adaptable subsea trenching device according to claim 5, characterized in that: The telescopic spray arm (5.7) includes several telescopic spray pipes (5.7.1) arranged side by side and several fixed pipes (5.7.2) arranged coaxially. The nozzle (5.4) is located at the bottom of the telescopic spray pipes (5.7.1). One end of the fixed pipe (5.7.2) is connected to the fixed base (5.5), and the other end of the fixed pipe (5.7.2) is fitted inside the telescopic spray pipe (5.7.1). A sealing ring (5.7.6) is provided on the outer wall of the other end of the fixed pipe (5.7.2). The sealing ring (5.7.6) is connected to the telescopic spray pipe. The inner wall of the pipe (5.7.1) is sealed. The telescopic spray pipe (5.7.1) includes a fixed spray section (5.7.3) and a telescopic spray section (5.7.4). The fixed spray section is located at the end of the telescopic spray section (5.7.4). The fixed spray section (5.7.3) is provided with a mounting seat (5.7.5) connected to one end of the length adjustment mechanism. The length adjustment mechanism can adjust the length of the telescopic spray arm relative to the fixed pipe (5.7.2).
8. The geologically adaptable subsea trenching device according to claim 5, characterized in that: The fixed base (5.5) includes a fixed plate (5.5.2) and a triangular, hollow hinge section (5.5.1). One end of the hinge section (5.5.1) is hinged to the liquid pipeline. The ends of the fixed spray arm (5.6), the telescopic spray arm (5.7), and the fixed plate (5.5.2) are all connected to the other end of the hinge section (5.5.1). The sides of the fixed spray arm (5.6) and the telescopic spray arm (5.7) are connected to the sides of the fixed plate (5.5.2).
9. The geologically adaptable subsea trenching device according to claim 1, characterized in that: The main frame (1) is equipped with an electric thruster (6) for adjusting the relative position of the submarine cable laying robot and the submarine cable. The electric thruster (6) includes side thrusters on four columns of the main frame and a tail thruster at the tail of the submarine cable laying robot. The axes of the four side thrusters form a certain angle with the direction of travel of the submarine cable laying robot, and the axis of the tail thruster is parallel to the direction of travel of the submarine cable laying robot.
10. The geologically adaptable subsea trenching device according to claim 1, characterized in that: The main frame (1) is equipped with a detection component (7) for detecting the relative position of the submarine cable laying robot and the submarine cable. The detection component (7) includes an external sensor (7.1) and an internal sensor (7.2). The internal sensor (7.2) is fixed on the main frame (1), and the external sensor (7.1) is mounted on the main frame (1) through a mounting bracket (7.3). The end of the mounting bracket (7.3) is hinged to the edge of the main frame (1). The mounting bracket (7.3) can rotate 90 degrees around the hinge point with the main frame. When the mounting bracket (7.3) is parallel to the horizontal plane, the external sensor (7.1) is parallel to the sea level.