Oil and gas pipeline inspection using underwater robots

Abstract

The invention discloses an underwater robot for oil and gas pipeline inspection, comprising a shell and a crawler chassis, a propulsion system and an inspection device; an anti-collision fairing is arranged at the rear of the shell, two balancing floats are symmetrically arranged on the left and right sides of the middle of the shell, and a control tow cable is fixedly arranged on the front of the shell; the propulsion system comprises a water inlet channel and a propeller; the crawler chassis is installed on the lower abdomen of the shell. The underwater robot for oil and gas pipeline inspection is specially designed for shallow sea, turbid and turbulent waters, and can quickly inspect submarine pipelines.

Description

Technical Field

[0001] The invention relates to the field of underwater robots, and in particular to an underwater robot for oil and gas pipeline inspection. Background Art

[0002] Submarine pipelines are the main arteries of offshore oil and gas transportation and an important part of offshore oil and gas fields. Due to long-term operation in complex marine environments, they are easily affected by various complex factors such as fishing activities and geological disasters, resulting in suspension, plane displacement, pipe damage, etc. Once leaked, it will cause serious environmental pollution and pose a great threat to the environment and production. On the other hand, my country has a history of laying submarine pipelines for decades, and the early submarine pipelines have already exceeded their designed service life or are about to exceed their design service life. Therefore, it is very important to accurately explore the status and location of submarine pipelines to prevent and eliminate safety hazards.

[0003] The traditional annual pipeline inspection practice is to adopt a towed side-scan sonar + underwater robot fixed-point inspection work mode. That is, two contractors are required to complete separate but related inspection activities in one mission. The first contractor uses a DP1-class geophysical survey ship equipped with a towed side-scan sonar for acoustic, open-water pipeline inspections. The collected sonar data is processed and interpreted to identify multiple most likely anomalies, and then another contractor is asked to use a DP2 support vessel and a work-class remotely operated unmanned submersible (ROV) to conduct a 500-meter routine visual inspection of each point, which consumes a lot of materials and time.

[0004] Autonomous underwater vehicles (AUVs) are easily lost on the seabed and are not as reliable as ROVs. In addition, general autonomous underwater vehicles are not suitable for installing large sensors, such as pipeline trackers, which have very high requirements for their navigation accuracy. In high-precision operations, they still rely on the support of the mother ship, and their battery capacity is limited and needs to be replaced regularly. Therefore, AUVs are suitable for close exploration in the deep sea.

[0005] In contrast, an operational ROV is a very versatile underwater carrier, but its awkward shape limits its speed to 1.5 knots and is easily disturbed in strong current conditions. On-site diving with an ROV after an acoustic survey is time-consuming and ineffective, and it is common to not find the survey target after diving due to misjudgment of the side scan data.

[0006] With the increasing maturity of acoustic sensors such as multi-beam echo sounders, shallow layer profilers, and side-scan sonars, their effective ranges have exceeded 50m, and detection tools are no longer a bottleneck restricting the inspection of submarine oil and gas pipelines. How to carry out long-term and frequent oil and gas pipeline inspections with these detection tools and perform efficient and accurate multi-sensor detection data processing has become an urgent problem to be solved. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides an underwater robot for oil and gas pipeline inspection, which is specially designed for shallow sea, turbid and turbulent waters and can quickly inspect submarine pipelines.

[0008] The technical solution adopted by the present invention is as follows:

[0009] An underwater robot for oil and gas pipeline inspection, comprising a shell, a crawler chassis, a propulsion system and an onboard inspection device;

[0010] The shell adopts a smoother hydrodynamic layout. An anti-collision fairing is arranged at the tail of the shell. Two balancing floats are symmetrically arranged on the left and right sides of the middle of the shell. The balancing floats are detachable. Several electronic compartments are arranged in the lower part of the inner shell of the balancing float to form a tumbler stable structure with light top and heavy bottom. Vertical stabilizing wings are arranged on the top surfaces of the two balancing floats. The two vertical stabilizing wings are symmetrical to each other. A hook is fixedly arranged on the top surface of the middle part of the shell. A rudder is arranged at the front of the shell. Two regulating horizontal wings are symmetrically arranged on the left and right sides of the middle of the rudder. A rudder controller and a horizontal wing controller are installed inside the rudder. The rudder controller is electrically connected to the rudder and controls the direction of the rudder. The horizontal wing controller is electrically connected to the regulating horizontal wing and controls the adjustment angle of the regulating horizontal wing. An underwater positioning system is arranged at the top of the front of the rudder. A control tow cable is fixedly arranged on the front of the shell. The control tow cable is an optoelectronic and tension composite tow cable. In addition to providing buoyancy and tension, it can also provide power and maintain signal transmission up and down.

[0011] The propulsion system includes a water inlet channel and a thruster. Horizontal water inlet channels A and B are symmetrically arranged at the rear end of the shell, and horizontal water inlet channels C and D are symmetrically arranged at the front end of the shell. Horizontal thrusters A, B, C, D are fixedly installed in the horizontal water inlet channels A, B, C, and D; four vertical water inlet channels are symmetrically arranged at the front and rear ends of the shell in the vertical direction, and vertical thrusters are fixedly installed in the four vertical water inlet channels respectively;

[0012] Furthermore, two reinforced thrusters are symmetrically arranged at the lower front end of the shell. The reinforced thrusters are attached. When the tugboat mode enters the fine detection stage, the ship stops and the robot actively detects with a small propulsion force. When sailing in a straight line, the reinforced thrusters are turned on to play a booster role, and are turned off for fine operation after approaching the target.

[0013] The onboard inspection equipment includes rotating lighting cameras arranged on the front, back, left and right sides of the lower abdomen of the shell, a front-view imaging sonar arranged in the front of the lower abdomen of the shell, a seabed ranging and collision avoidance sonar arranged at the front end of the bottom of the lower abdomen of the shell, a shallow layer profiler arranged behind the seabed ranging sonar, a side-scan sonar suspended under the crawler chassis, a laser ruler arranged on the side-scan sonar, an ultra-high resolution static camera arranged on the rear end of the lower abdomen of the shell, flashlights arranged on the left and right sides of the ultra-high resolution static camera, and an ultra-high-definition 4K camera arranged at the tail end of the shell. The onboard inspection equipment is all controlled by a control tow cable.

[0014] The crawler chassis is installed on the lower abdomen of the shell.

[0015] Furthermore, when inspecting pipelines and submarine cables buried at a depth greater than one meter, the effect of using hydroacoustic detection is not good, and it is necessary to install a TSS440 cable tracker at the front end of the shell. The TSS440 cable tracker uses electromagnetic waves with a specific spectrum combination to transmit to the seabed, and calculates the direction, thickness, and burial depth of buried pipelines and submarine cables by detecting the recovered signals. However, because seawater has strong shielding and attenuation characteristics for electromagnetic waves, it is necessary to place the antenna as close as possible to the seabed to listen for signals. Since the three antenna coils of the TSS440 cable tracker are heavy, and in order to prevent electromagnetic signal interference, they need to be kept more than 2 meters away from the mother body, so buoyancy blocks are added to the cantilever arm of the TSS440 cable tracker to balance the weight distribution and prevent top-heavy.

[0016] Furthermore, the shell is made of carbon fiber material.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. Taking into account the characteristics of both ordinary ROV and AUV, the appearance of AUV, the control of ROV, and the efficiency are greatly improved.

[0019] 2. It has the functions of quick inspection and detailed inspection. Problems can be found out in one voyage, saving construction time and sea expenses.

[0020] 3. Reduce seawater resistance, design the shape into a smooth hydrodynamic layout like an aircraft, and arrange the propeller water inlet channel reasonably. The working speed of pipeline acoustic measurement is expected to reach 5 knots, which can adapt to the highest level 6 severe sea conditions, which is 2-3 times the speed of ordinary ROV or AUV inspection.

[0021] 4. The carbon fiber shell is light and strong, making it easy to load and unload the ship.

[0022] 5. Real-time online inspection provides seabed inspection data, and telemetry data is synchronously transmitted to the surface monitoring station via optical fiber. If a problem is found, the ship can be stopped in time for detailed inspection at a fixed point, and quick inspection can be resumed immediately after the detailed inspection.

[0023] 6. Fiber optic transmission has a large bandwidth for information and data transmission and exchange, and the quality of collected data is high.

[0024] 7. In order to effectively control the stability of underwater height, the upper hull design of a nuclear submarine is adopted, and adjustable horizontal wings and rudders are arranged. The angle of the horizontal wings can be adjusted at any time according to the seabed ranging sonar values, allowing it to move smoothly in the sea like an airplane.

[0025] 8. An elastic anti-collision deflector is installed at the front section to reduce resistance and prevent accidental damage.

[0026] 9. Holes and slots are opened at different positions under the belly to facilitate the placement of sensors with different functions. Multiple sensors can be installed at the same time to solve many problems in one voyage.

[0027] 10. Equipped with 10 high-thrust propellers. Four of them are arranged horizontally, responsible for horizontal movement at any angle, such as front and back, left and right, and can also turn left and right; the other four are arranged vertically, responsible for up and down movement, and can also adjust the body's climbing and pitching posture, and have stable hovering capabilities during detailed exploration of fixed points in the water. The two rear ones enhance forward thrust.

[0028] 11. The complex multi-thruster design, with the assistance of software, can effectively overcome the yaw effect of ocean currents on the towed vehicle.

[0029] 12. The submarine crawler designed in the shape of an aircraft landing gear can form a grip under the action of the four vertical thrusters on the back, and rely on the crawler to adhere to the seabed for close observation, forming a stable and clear video image. Some damaged sea areas may have strong currents. The machine can also resist strong currents under the combined action of the four horizontal vector thrusters and the two reinforced thrusters at the tail.

[0030] 13. The center of gravity and the center of buoyancy are reasonably arranged to adapt to high-speed and stable underwater navigation.

[0031] 14. The control software can turn on the spot and move left and right, and can accurately control the height above the ground. It can correct the heading and align the survey line, which saves a lot of time for turning and aligning the survey line and has high measurement accuracy.

[0032] 15. The three-dimensional image model can also enable users to better understand the relationship between the pipeline and its ancillary structures and the seabed, bringing great convenience to construction and repair.

[0033] 16. More sensors can be carried, including previous sensors (MBES, SSS, HD cameras, pipeline trackers) and new sensors (UHD static cameras, laser rulers, 3D laser imagers, ultra-high-definition cameras), etc.

[0034] 17. Sufficient power to meet the power supply needs of complex detection equipment and larger operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0036] Figure 2 It is a schematic cross-sectional view of the structure of an embodiment of the present invention.

[0037] Figure 3 Schematic diagram of the structural arrangement of a propulsion system according to an embodiment of the present invention.

[0038] Figure 4 It is a schematic diagram of the structural layout of the onboard inspection equipment according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned objects, features and advantages of the invention more obvious and understandable, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0040] Example 1

[0041] The following is combined with Figure 1-4 The present invention is further described in detail with reference to the accompanying drawings and embodiments.

[0042] An underwater robot for oil and gas pipeline inspection, comprising a housing 1, a crawler chassis 2, a propulsion system and an onboard inspection device;

[0043] The shell 1 adopts a smoother hydrodynamic layout. An anti-collision deflector 11 is arranged at the tail of the shell. Two balancing floats 12 are symmetrically arranged on the left and right sides of the middle of the shell. The balancing float 12 is detachable. Several electronic compartments are arranged in the lower part of the inner shell of the balancing float 12 to form a tumbler stable structure with light top and heavy bottom. Vertical stabilizing wings 13 are arranged on the top surfaces of the two balancing floats 12. The two vertical stabilizing wings are symmetrical to each other. A hook 14 is fixedly arranged on the top surface of the middle of the shell 1. A rudder 15 is arranged at the front of the shell 1. Two regulating horizontal wings 16 are symmetrically arranged on the left and right sides of the middle of the rudder 15. The rudder 15 is equipped with a rudder controller 17 and a horizontal wing controller 18. The rudder controller 17 is electrically connected to the rudder 15 and controls the direction of the rudder 15. The horizontal wing controller 18 is electrically connected to the regulating horizontal wing 16 and controls the adjustment angle of the regulating horizontal wing 16. A short baseline underwater hydroacoustic locator 19 is arranged on the top of the front part of the rudder 15, and a satellite surface positioning antenna 19A is arranged on the top of the rear part of the rudder 15. The short baseline underwater hydroacoustic locator 19 and the satellite surface positioning antenna 19A are both electrically connected to the rudder 15. A control towline 10 is fixedly arranged on the front of the housing 1;

[0044] The propulsion system includes a water inlet channel and a propeller. The rear end of the shell 1 is symmetrically provided with a horizontal water inlet channel A31 and a horizontal water inlet channel B32, and the front end of the shell is symmetrically provided with a horizontal water inlet channel C33 and a horizontal water inlet channel D34. Horizontal propellers A35, B36, C37 and D38 are fixedly installed in the horizontal water inlet channels A, B, C and D; four vertical water inlet channels 39 are symmetrically provided at the front and rear ends of the shell 1 in the vertical direction, and vertical propellers 30 are fixedly installed in the four vertical water inlet channels 39 respectively;

[0045] Two enhanced thrusters 101 are symmetrically arranged at the lower front end of the shell. The enhanced thrusters are attached. When the tugboat mode enters the fine detection stage, the ship stops and the robot actively detects with a small propulsion force. When sailing in a straight line, the enhanced thrusters are turned on to play a booster role and are turned off for fine operation after approaching the target);

[0046] The onboard inspection equipment includes a rotating lighting camera device 41 arranged on the front, rear, left and right sides of the lower abdomen of the shell, a front-view imaging sonar 42 arranged in the front of the lower abdomen of the shell, a seabed ranging and collision avoidance sonar 43 arranged at the front end of the bottom of the lower abdomen of the shell, a shallow layer profiler 44 arranged behind the seabed ranging sonar, a side scanning sonar 45 suspended under the crawler chassis, a laser ruler 46 arranged on the side scanning sonar, an ultra-high resolution static camera 47 arranged on the rear end face of the lower abdomen of the shell, a flash 48 arranged on the left and right sides of the ultra-high resolution static camera, and an ultra-high-definition 4K camera 49 arranged at the tail end of the shell. The onboard inspection equipment is directly purchased from the market, and its structure is not described in detail here.

[0047] The crawler chassis 2 is installed on the lower abdomen of the shell 1.

[0048] In this embodiment, the tracked chassis 2 adopts a lightweight underwater tracked chassis produced by Qingdao Ganhai Robot Co., Ltd. (patent application number: 2020107070871).

[0049] In addition, when detecting pipelines and submarine cables with a buried depth greater than one meter, the effect of using hydroacoustic detection is not good, and it is necessary to install a TSS440 cable tracker 5 at the front end of the shell. The TSS440 cable tracker 5 uses electromagnetic waves with a specific spectrum combination to transmit to the seabed, and calculates the direction, thickness, and burial depth of buried pipelines and submarine cables by detecting the recovered signals. However, because seawater has strong shielding and attenuation characteristics for electromagnetic waves, it is necessary to place the antenna as close as possible to the seabed to listen for signals. Since the three antenna coils of the TSS440 cable tracker are heavy, and in order to prevent electromagnetic signal interference, they need to be kept at a distance of more than 2 meters from the mother body, so a buoyancy block 51 is added to the cantilever arm of the TSS440 cable tracker to balance the weight distribution and prevent top-heavy.

[0050] The process of using the underwater robot to detect the shallow bottom layer during the oil and gas pipeline inspection of this embodiment is as follows:

[0051] Before the operation, the path of the tugboat is planned according to the coordinates of the construction drawing, and the ROV is hoisted and lowered to the working sea area. After the towing and landing is normal, the position is calibrated through the Beidou signal device on the top of the ROV, and a rapid general scan is performed. The appropriate length of the towline is released as needed, and the working height above the ground is set, and then the buried pipeline is measured autonomously. When a suspicious point is found during the general scan, the ship is stopped immediately, the cable car on the tugboat is operated to release the appropriate length of cable, and the ROV is controlled to sail backward to the suspicious position, slowly lower the height, hover and film the suspected area, and then land on one side, and spray water on the back to generate downward grip, drive with crawlers, and slowly approach for detailed shooting; after shooting, take off and land on the other side, and also drive with crawlers for detailed shooting, so that detailed and clear video data can be obtained. Then lift to a suitable height above the ground and continue to drive the tugboat for general scanning. After the general scan is completed, the ROV is recovered on the ship. The above description is only a preferred specific implementation manner of the invention, but the protection scope of the invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An underwater robot for oil and gas pipeline inspection, characterized in that: It includes the shell, crawler chassis, propulsion system and onboard inspection equipment; An anti-collision fairing is arranged at the rear of the shell, two balancing floats are symmetrically arranged on the left and right sides of the middle of the shell, a number of electronic compartments are arranged in the lower part of the inner shell of the balancing float to form a structure that is light on the top and heavy on the bottom, vertical stabilizing wings are arranged on the top surfaces of the two balancing floats, and the two vertical stabilizing wings are symmetrical to each other, a hook is fixedly arranged on the top surface of the middle of the shell, a rudder is arranged at the front of the shell, and two regulating horizontal wings are symmetrically arranged on the left and right sides of the middle of the rudder, a rudder controller and a horizontal wing controller are installed inside the rudder, the rudder controller is electrically connected to the rudder and controls the direction of the rudder, the horizontal wing controller is electrically connected to the regulating horizontal wing and controls the adjustment angle of the regulating horizontal wing, an underwater positioning system is arranged on the top of the front of the rudder, and a control tow cable is fixedly arranged on the front of the shell; The propulsion system includes a water inlet channel and a propeller. Horizontal water inlet channels A and B are symmetrically arranged at the rear end of the shell, and horizontal water inlet channels C and D are symmetrically arranged at the front end of the shell. Horizontal propellers A, B, C, and D are fixedly installed in the horizontal water inlet channels A, B, C, and D; four vertical water inlet channels are symmetrically arranged at the front and rear ends of the shell in the vertical direction, and vertical propellers are fixedly installed in the four vertical water inlet channels respectively; The onboard inspection equipment includes a rotating lighting camera device arranged on the front, rear, left and right sides of the lower abdomen of the shell, a three-dimensional forward-looking sonar arranged at the front of the lower abdomen of the shell, a seabed ranging sonar arranged at the front end of the bottom of the lower abdomen of the shell, a shallow layer profiler arranged behind the seabed ranging sonar, a side-scan sonar arranged on the crawler chassis, a laser ruler arranged on the side-scan sonar, an ultra-high-resolution static camera arranged on the rear end of the lower abdomen of the shell, flashlights arranged on the left and right sides of the ultra-high-resolution static camera, and an ultra-high-definition 4K camera arranged at the tail end of the shell; The crawler chassis is installed on the lower abdomen of the shell.

2. The underwater robot for oil and gas pipeline inspection according to claim 1, characterized in that: Two reinforced thrusters are symmetrically arranged externally at the lower front end of the shell.

3. The underwater robot for oil and gas pipeline inspection according to claim 2 is characterized in that: When inspecting pipelines and submarine cables buried at a depth of more than one meter, a TSS440 pipe and cable tracker is installed at the front end of the shell, and a buoyancy block is added to the cantilever arm of the TSS440 pipe and cable tracker.

4. The underwater robot for oil and gas pipeline inspection according to claim 3 is characterized by: The shell is made of carbon fiber material.

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