A trackless submarine pipeline nondestructive testing device

Abstract

The present invention relates to the field of marine equipment technology, and aims to provide a trackless non-destructive testing device for submarine pipelines. The device is provided with a self-propelled non-destructive testing mechanism in a scanning cabin, including an annular holding rail, an axial electric cylinder, a testing mechanism and a radial electric cylinder; wherein the annular holding rail is composed of a symmetrically arranged semicircular left holding rail and a right holding rail, with a holding support wheel provided inside, and an annular rack and an annular track formed by splicing on the outside; the axial electric cylinder is arranged along the axial direction, and the radial electric cylinder is arranged perpendicular to the axial electric cylinder and a testing mechanism is fixedly installed on the top; the mounting frame of the testing mechanism is provided with a linear module, and three probes are provided on the mounting frame and the slider of the linear module. The present invention does not require additional fixed support and guide rails or track mechanisms for auxiliary movement, and can realize axial movement of the non-destructive testing mechanism only by self-drive; it can simplify the equipment, reduce the failure rate, reduce equipment cost and maintenance work.

Description

Technical Field

[0001] The present invention relates to the technical field of marine equipment, and in particular to a trackless submarine pipeline non-destructive testing device. Background Art

[0002] Offshore oil and natural gas transportation relies on submarine pipelines. During operation, submarine oil and gas pipelines are often subject to corrosion from both internal and external environments. Internal corrosion primarily results from the transported medium, accumulated fluids, and contaminants corroding the inner pipe wall. External corrosion is caused by seawater infiltration due to coating damage or failure, which corrodes the outer pipe wall. Sometimes, the combined effects of stress on the pipe wall and corrosion can cause dangerous stress corrosion cracking. Therefore, regular submarine pipeline inspection and repair are essential.

[0003] Before and after the repair of submarine pipelines, non-destructive testing of submarine pipelines is required. However, traditional non-destructive testing of submarine pipelines requires divers to use underwater corrosion detection probes, and can only perform corrosion detection on the pipeline wall. Diver testing has many disadvantages: (1) Due to the limitation of the diver's diving depth, non-destructive testing at a depth of more than 50m is difficult to complete. (2) Due to the short diving time, the diver's single scan length is short, and frequent dives are required. (3) Divers are at great risk during underwater operations. (4) Conventional underwater testing can only detect cracks, corrosion, etc. on submarine pipelines, and it is difficult to check the evolution of welds in the welding parts of underwater submarine pipelines.

[0004] Chinese patent application CN115468123 A discloses a tool and method for accurately mapping deformation defects in submarine pipelines. For a pipeline maintenance section, a scanning chamber embraces the submarine pipeline. A pumping device within the chamber replaces the seawater with air, creating a dry chamber. A 3D scanning drive then drives the 3D scanner, performing a full-scale scan of the submarine pipeline within the chamber. The cam is connected to the drive shaft of the motor to move the motor, and the cam is connected to the drive shaft by the gear train of the motor, and the cam is connected to the transmission gear of the motor.

[0005] From the technical content disclosed in this document, it can be known that the premise for the three-dimensional scanner in the submarine pipeline deformation defect precision mapping tool to be able to stably displace along the axial direction of the pipeline is that the multiple linear guides on which its circular arc guide rails are installed must always remain parallel to the pipeline. However, on the one hand, the linear guides cannot maintain parallel positioning by themselves, and on the other hand, they can self-drive to achieve axial translation to change the detection area. Therefore, it is necessary to additionally configure a fixed support and a moving mechanism (that is, the three-dimensional scanning drive device described in this document). This is bound to make the relevant structure more complicated. This further causes problems such as easy parallel deviation, difficulty in maintaining stable operation, and easy damage leading to increased maintenance workload.

[0006] Therefore, it is in line with practical needs to provide a three-dimensional scanner support structure with a simpler structure and more stable operation. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a trackless submarine pipeline non-destructive testing device.

[0008] To solve the technical problem, the solution of the present invention is:

[0009] Provided is a trackless submarine pipeline non-destructive testing device, comprising an outer frame, a scanning cabin, and a scanning cabin pumping device; a self-propelled non-destructive testing mechanism is provided in the scanning cabin, the non-destructive testing mechanism comprising an annular holding rail, an axial electric cylinder, a testing mechanism, and a radial electric cylinder; wherein,

[0010] The annular holding rail is arranged around the pipe being measured and consists of symmetrically arranged semicircular left and right holding rails. The outer side of the annular holding rail has a spliced ​​annular rack and annular track, and at least three holding support wheels are evenly arranged along the circumference on its inner side. The rollers at the bottom of the holding support wheels are mounted on the annular holding rail through brackets and elastic components, and are used to hold the pipe being measured and assist the annular holding rail in moving axially along the pipe.

[0011] The axial electric cylinder is arranged along the axial direction of the pipeline to be measured, and its cylinder body is mounted on the annular holding rail via a rotating platform. The top end of the telescopic rod is fixedly connected to the cylinder body of the radial electric cylinder. The rotating platform includes a pulley, a gear, and a rotary motor. The pulley is embedded in the annular track, the gear is meshed with the annular rack, and the end of the output shaft of the rotary motor is connected to the gear. The radial electric cylinder is arranged perpendicular to the axial electric cylinder, and its telescopic rod faces the central axis of the pipeline to be measured, with a detection mechanism fixedly installed at the top end.

[0012] The detection mechanism includes a mounting frame, the upper portion of which is fixedly connected to the top end of the telescopic rod of the radial electric cylinder; a linear module is provided at the lower portion of the mounting frame and is arranged axially along the pipeline to be tested. The linear module includes a servo motor, a linear guide, a ball screw and a slider. The slider is seated on the linear guide and is driven to move by the ball screw; the detection mechanism includes multiple probes, and at least includes a first probe and a second probe for detecting welds, and a third probe for detecting corrosion; wherein the first probe is fixedly mounted on the mounting frame by a probe clamp, and the second probe and the third probe are each fixedly mounted on the same slider by a probe clamp; the first probe and the second probe are arranged opposite each other, and an adjustable distance is retained between them for detecting welds.

[0013] As a preferred solution of the present invention, the tops of the left holding rail and the right holding rail are connected by a rotating shaft; electromagnets are respectively provided at the junction of the bottoms of the two, for attracting and fixing the pipe when clamping it; and lifting ears are respectively provided at the rotating shaft, the middle of the left holding rail, and the middle of the right holding rail, for installing a rope for lifting or pulling.

[0014] As a preferred solution of the present invention, a group of docking wheels are respectively provided on the side surfaces of the two docking ends of the left holding rail and the right holding rail; the docking wheels include a cam and a concave wheel and the shapes of the outer edges of the two cooperate with each other, playing a guiding role when the left holding rail and the right holding rail are closed.

[0015] As a preferred embodiment of the present invention, the left holding rail and the right holding rail have the same main structure, both including two semicircular plates arranged alternately and several intermediate horizontal plates for connecting the two; a semicircular rack is arranged between the two semicircular plates, and one of the plates is used as a track for installing the rotating table; the clamping support wheel is installed on the intermediate horizontal plate.

[0016] As a preferred embodiment of the present invention, the clamping support wheel includes a gas spring, a ball bearing and a bracket connected in sequence; the two rollers are installed in parallel in the bracket and arranged along the axial direction of the measured pipeline; the gas spring is fixed on the annular holding rail, and can extend and contract along the radial direction of the measured pipeline while maintaining a constant extended state, and is used to realize a passive compensation function after the annular holding rail holds the pipeline; the roller can roll along the axial direction of the pipeline driven by the annular holding rail to reduce friction.

[0017] As a preferred solution of the present invention, the rotary table includes a clamping mount, and the cylinder body of the axial electric cylinder is fixed on its side; the rotary motor is installed in the middle position of the clamping mount, the output shaft of the motor passes through the clamping mount, and the gear is fixed to the end of the output shaft; 4 pulleys are provided inside the clamping mount, with one group on each side of the output shaft of the rotary motor, and each group of pulleys is movably embedded in cooperation with each other on both sides of the annular track.

[0018] As a preferred embodiment of the present invention, the probe clamp includes a rear support plate, a middle slide rail, a front support plate and a horizontal support plate; the front support plate is in a Z-shaped bend shape and the bend angle is a right angle, one of the vertical folded edges is fixed to the side of the slider or the mounting bracket by a screw, and the other vertical folded edge is fixedly connected to the middle slide rail; the rear support plate and the middle slide rail are in sliding cooperation and can slide up and down in the vertical direction; the bottom of the rear support plate is movably connected to the horizontal support plate by a screw in the x-axis direction, and the horizontal support plate can rotate around the x-axis; the probe is movably connected to the horizontal support plate by a screw in the y'-axis direction, and the probe can rotate around the y'-axis; the rear support plate and the front support plate are connected by a spring and form a downward pre-tightening force, which is used to provide passive compensation so that the probe is tightly attached to the surface of the pipe to be measured.

[0019] As a preferred embodiment of the present invention, the probe includes a probe body and a wedge. The wedge is located below the probe body. The probe body is used to convert electrical signals into acoustic signals, and the wedge is used to closely adhere to the pipeline and transmit the acoustic signals of the probe body to the inner wall of the pipeline. The wedge is provided with a water pipe joint on the upper side and a groove on the bottom, which is connected by an internal channel. The water pipe joint is connected to the coupling agent box via a hose, and the coupling agent box is filled with clean water as a coupling agent.

[0020] As a preferred solution of the present invention, the axial electric cylinder, radial electric cylinder, rotary motor, servo motor and electromagnet are respectively connected to a control host of the ultrasonic detection system provided on the mother ship via cables.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] In this invention, the clamping support wheels within the annular rail simultaneously hold the pipe under test and assist the rail's axial movement along the pipe. After the radial electric cylinder presses the probe against the pipe under test, the action of the axial electric cylinder causes the annular rail to move axially along the pipe. Therefore, within the effective scanning area of ​​the scanning chamber, this invention eliminates the need for additional fixed supports or guide rails or track mechanisms to assist movement, and can achieve axial movement through self-propelled nondestructive testing.

[0023] 2. In the present invention, the annular holding rail is composed of a symmetrically arranged semicircular left holding rail and a right holding rail. After the splicing is completed, the annular holding rail relies on the rotating shaft and the electromagnet to form a stable structure; therefore, the circumferential movement of the entire detection mechanism can be achieved by driving only one rotating motor; compared with the existing technology (in the background technology), it can enhance the performance of the circumferential support structure while reducing the use of circumferential operation drive equipment.

[0024] 3. The present invention utilizes the sliding fit between the rear support and the middle rail in the probe clamp, and the downward preload force formed by the spring connection between the rear support and the front support, to provide passive compensation to keep the probe in close contact with the surface of the pipe being tested. Simultaneously, the movable connection between the rear support and the horizontal support, and the movable connection between the probe and the horizontal support, allows for adjustable fit between the probe and the pipe surface in two mutually perpendicular directions. Combined with the design of the coupling agent addition mechanism, the present invention can reduce interference during ultrasonic testing compared to the prior art (in the background art), achieving superior testing results.

[0025] 4. This invention utilizes dry chamber technology for nondestructive testing, enabling simultaneous assessment of both the surface and weld damage of submarine pipelines, providing data support for subsequent maintenance work. Furthermore, with its streamlined structural design, this invention simplifies equipment, reduces failure rates, and reduces equipment costs and maintenance workload. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the overall structure of the nondestructive testing mechanism of the present invention;

[0027] Figure 2 This is a structural diagram of a circular rail holding device;

[0028] Figure 3 It is a schematic diagram of the structure of the holding support wheel;

[0029] Figure 4 This is the coordination diagram between the rotating table and the circular holding rail;

[0030] Figure 5 This is a schematic diagram of the direction of the corrosion detection probe;

[0031] Figure 6 This is a schematic diagram of the weld inspection probe orientation;

[0032] Figure 7 Schematic diagram of the probe clamp structure.

[0033] The reference numerals in the figure are: 1 annular holding rail, 1-1 docking wheel, 1-2 left holding rail, 1-3 holding support wheel, 1-3-1 gas spring, 1-3-2 ball bearing, 1-3-3 roller, 1-4 rotating table, 1-4-1 slide plate, 1-4-2 pulley, 1-5 rotating motor, 1-6 lifting eye, 1-7 rack, 1-8 right holding rail, 2 axial electric cylinder, 3 detection system, 3-1 control host, 3-2 third probe, 3-3 probe clamp, 3-3-1 rear support plate, 3-3-2 middle slide rail, 3-3-3 front support plate, 3-3-4 horizontal support plate, 3-4 linear module, 3-5 servo motor, 3-6 coupling agent box, 3-7 second probe, 3-8 first probe, 4 radial electric cylinder, 5 measured pipeline. DETAILED DESCRIPTION

[0034] The serial numbers assigned to the components in this application, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of this application, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0035] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0036] The technical solutions of the present invention will be described in detail below through embodiments with reference to the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0037] The trackless submarine pipeline nondestructive testing device of the present invention includes an outer frame, a scanning cabin, and a scanning cabin pumping device. The implementation of these structures can refer to the contents described in Chinese patent application CN115468123 A or other public documents. As long as similar structures can provide waterless testing conditions for the scanning cabin, they are applicable, and the present invention does not make special requirements.

[0038] In the scanning cabin, there are Figure 1The self-propelled nondestructive testing mechanism shown in the figure comprises a circular holding rail 1, an axial electric cylinder 2, a testing mechanism 3, and a radial electric cylinder 4. The circular holding rail 1, arranged around the pipe 5 to be tested, consists of a symmetrically arranged left and right semicircular holding rails 1-2 and 1-8. The left and right holding rails 1-2 and 1-8 share the same main structure, consisting of two alternating semicircular segments and several intermediate cross plates for connection. A semicircular rack 1-7 is positioned between the two segments, with one segment serving as a track for mounting a rotating platform 1-4. The tops of the two holding rails are connected by a rotating shaft, and electromagnets are located at their bottom junctions to secure the circular holding rail 1 in place when it clamps to the pipe. A pair of docking wheels 1-1 are located on the sides of the two holding rails' butt joints. The docking wheels 1-1 consist of a cam and a concave wheel, with their outer edges shaped to complement each other, guiding the rails as they close. Lifting lugs are located at the pivot and in the middle of the left and right holding rails for attaching winches for lifting or pulling. The other end of the winch is connected to an electric winch inside the scanning cabin. The outer circumference of the annular holding rail 1 is composed of a spliced ​​ring rack and a ring track. At least three holding support wheels 1-3 are evenly spaced around its inner circumference.

[0039] like Figure 2 、 3 As shown, the clamping support wheel 1-3 comprises a gas spring 1-3-1, a ball bearing 1-3-2, and a bracket, all connected in sequence. Two rollers 1-3-3 are mounted in parallel in the bracket along the axial direction of the pipe 5 being measured. The gas spring 1-3-1 is fixed to the middle cross plate of the annular clamping rail 1. The multiple clamping support wheels 1-3 are used to clamp the pipe 5 being measured and assist the annular clamping rail 1 in its axial movement. While remaining permanently extended, they can extend and contract radially along the pipe 5 being measured. Once the annular clamping rail 1 is clamped to the pipe, it can be used to implement passive compensation. Driven by the annular clamping rail 1, the rollers roll axially along the pipe to reduce friction.

[0040] like Figure 4 As shown, the rotating platform 1-4 includes a clamping mount 1-4-1, to the side of which the cylinder body of the axial electric cylinder 2 is fixed. The rotating motor 1-5 is mounted in the center of the clamping mount 1-4-1. The motor's output shaft passes transversely through the clamping mount 1-4-1. A gear is fixed to the end of the output shaft, meshing with the annular rack. Four pulleys 1-4-2 are located within the clamping mount 1-4-1, one set on each side of the output shaft of the rotating motor 1-5. Each set of pulleys is movably mounted on either side of the annular track.

[0041] like Figure 1As shown, the axial electric cylinder 2 is arranged axially along the pipe 5 being tested. Its cylinder body is mounted on the annular holding rail 1 via a rotating platform 1-4. The top end of the telescopic rod is fixedly connected to the cylinder body of the radial electric cylinder 4. The radial electric cylinder 4 is arranged perpendicular to the axial electric cylinder 2, with its telescopic rod facing the central axis of the pipe 5 being tested and the detection mechanism 3 fixed to its top end. Because the holding support wheels 1-3 can hold the pipe with their elastic support force, the gears can move along the annular rack driven by the rotating motor 1-5, thereby achieving the axial rotation of the axial electric cylinder 2, the detection mechanism 3, and the radial electric cylinder 4 along the circumference of the pipe 5 being tested, driven by the rotating platform 1-4.

[0042] like Figure 5 、 6 As shown, the detection mechanism 3 includes a mounting frame, the upper portion of which is fixedly connected to the top of the telescopic rod of the radial electric cylinder 4. At the lower portion of the mounting frame, a linear module 3-4 is provided, arranged axially along the pipeline to be tested. The linear module 3-4 includes a servo motor 3-5, a linear guide, a ball screw, and a slider. The slider is seated on the linear guide and is driven by the ball screw driven by the servo motor 3-5 to achieve movement. The detection mechanism 3 includes multiple probes, including at least a first probe 3-8 and a second probe 3-7 for detecting welds, and a third probe 3-2 for detecting corrosion. The first probe 3-8 is fixedly mounted on the mounting frame via a probe clamp 3-3, and the second probe 3-7 and the third probe 3-2 are each fixedly mounted on either side of the same slider via the probe clamp 3-3. The first probe 3-8 and the second probe 3-7 are arranged opposite each other, and an adjustable distance is retained between them for detecting welds. The main structures of each probe are essentially similar, consisting of a probe body and a wedge. The wedge is located below the probe body. The probe body is used to convert electrical signals into acoustic signals, while the wedge is used to closely adhere to the pipe and transmit the acoustic signals from the probe body to the inner wall of the pipe. The wedge has a water pipe connector on its upper side and a slot on its bottom, which is connected by an internal channel. The water pipe connector is connected to the couplant tank 3-6 via a hose, which is filled with clean water as a couplant. In the present invention, the probes used for weld and corrosion detection all use existing ultrasonic testing technology, which is not specifically required by the present invention.

[0043] like Figure 7As shown, the probe clamp 3-3 includes a rear support piece 3-3-1, a middle slide rail 3-3-2, a front support piece 3-3-3 and a horizontal support piece 3-3-4; the front support piece 3-3-3 is in a Z-shaped bending shape and the bending angle is a right angle, one of the vertical folded edges is fixed to the side of the slider or the mounting bracket by a screw, and the other vertical folded edge is fixedly connected to the middle slide rail 3-3-2; the rear support piece 3-3-1 and the middle slide rail 3-3-2 are in sliding cooperation and can slide up and down in the vertical direction; the bottom of the rear support piece 3-3-1 is movably connected to the horizontal support piece 3-3-4 by a screw in the x-axis direction, and the horizontal support piece 3-3-4 can rotate around the x-axis; the probe is movably connected to the horizontal support piece 3-3-4 by a screw in the y'-axis direction, and the probe can rotate around the y'-axis; the rear support piece 3-3-1 and the front support piece 3-3-3 are connected by a spring and form a downward pre-tightening force, which is used to provide passive compensation to make the probe close to the surface of the measured pipe 5.

[0044] In the present invention, the axial electric cylinder 2, radial electric cylinder 4, rotary motors 1-5, and servo motors 3-5 are each connected via cables to a control host of the ultrasonic detection system located on the mother ship. The control technology of the ultrasonic detection system is mature and is not specifically required by the present invention.

[0045] A more detailed description follows:

[0046] like Figure 1 As shown, the trackless submarine pipeline non-destructive testing device of the present invention is realized based on the dry chamber technology. The structure and operation of the dry chamber and the ultrasonic testing system can be referred to the records in the existing public documents.

[0047] The nondestructive testing device includes: a circular holding rail 1, an axial electric cylinder 2, a detection system 3, and a radial electric cylinder 4. The circular holding rail 1 is used to hold and secure the pipeline, while the axial electric cylinder 2 is used to move the detection system 3 axially along the pipeline. The bottom of the axial electric cylinder 2 is fixed to the rotating table 1-4 and can be extended and retracted along the pipeline axis, thereby moving the detection system 3 axially along the pipeline axis. The bottom of the radial electric cylinder 4 is fixed to the end of the telescopic rod of the axial electric cylinder 2 and can be extended and retracted along the pipeline axis, thereby moving the detection system 3 radially along the pipeline axis. Both the axial electric cylinder 2 and the radial electric cylinder 4 are high-precision underwater electric cylinders with a displacement accuracy of 0.01 mm. The detection system 3 is used to detect surface corrosion and weld evolution of the submarine pipeline 5.

[0048] like Figure 2As shown, the annular holding rail 1 includes a docking wheel 1-1, a left holding rail 1-2, a clamping support wheel 1-3, a rotating platform 1-4, a rotating motor 1-5, a lifting lug 1-6, a rack 1-7, and a right holding rail 1-8. The left holding rail 1-2 consists of two semicircular segments with a horizontal plate in between. A rotating shaft is located at the top of one of the segments, and two circular docking wheels 1-1 are located below the shaft and at the bottom of the semicircular segments. The structure of the right holding rail 1-8 is similar to that of the left holding rail 1-2. The rotating shaft coordinates the rotation of the left holding rail 1-2 and the right holding rail 1-8 to achieve opening and closing of the bottom. When closing, the docking wheels 1-1 provide guidance. Underwater electromagnets are placed at the bottom of the left holding rail 1-2 and the right holding rail 1-8 to secure the left holding rail 1-2 to the right holding rail 1-8. A rack 1-7 is fixed to the side of the other plate. When the left holding rail 1-2 and the right holding rail 1-8 are closed, the rack 1-7 of the left holding rail 1-2 and the right holding rail 1-8 form a complete annular rack. The rotating table 1-4 forms a rolling fit with the corresponding plate and can rotate circumferentially along the annular rack. The rotating motor 1-5 is fixed to the rotating table 1-4, and the rotating motor 1-5 drives the gear to rotate the rotating table 1-4 along the rack 1-7. The clamping support wheel 1-3 for passive compensation is fixed to the middle horizontal plate. When the left holding rail 1-2 and the right holding rail 1-8 are closed, the annular holding rail 1 can clamp the pipeline and cooperate with the axial movement of the annular holding rail 1 along the pipeline to reduce resistance.

[0049] like Figure 3 As shown, the clamping support wheel 1-3 comprises a gas spring 1-3-1, a ball bearing 1-3-2, and a roller 1-3-3. Gas spring 1-3-1 is fixed to the horizontal plate in the center of the circular clamping rail 1. It can extend and contract radially along the pipeline, maintaining a constant extension force, thus achieving passive compensation after the circular clamping rail 1 has gripped the pipeline. The end of gas spring 1-3-1 is connected to roller 1-3-3 via ball bearing 1-3-2, and roller 1-3-3 can roll axially along the pipeline. A lifting lug 1-6 is fixed to each of the left clamping rail 1-2, the right clamping rail 1-8, and the rotating shaft. Correspondingly, an electric winch is fixed to the left half, right half, and top of the scanning cabin (dry cabin) wall, respectively. The winch is connected to each of the three lifting lugs via a winch rope.

[0050] like Figure 4 As shown, the rotating platform 1-4 comprises a clamping mount 1-4-1 and pulleys 1-4-2. The clamping mount 1-4-1 is gate-shaped, with a set of pulleys 1-4-2 located on either side of the output shaft of the rotating motor 1-5. The two pulleys in each set are located on either side of the annular track and are movably mounted to each other, enabling the rotating platform 1-4 to rotate circumferentially along the annular holding track 1 through the meshing of the rack and pinion.

[0051] like Figure 5 、 6As shown, the inspection system 3 is fixed to the end of the radial electric cylinder 4 and includes a servo motor 3-5, a linear module 3-4, three sets of probe clamps 3-3, and three probes for inspecting submarine pipelines 5. The main unit 3-1 is a control unit used in conventional ultrasonic inspection systems, housed on the mother ship. It transmits and receives ultrasonic signals and displays internal damage to the pipe wall. The linear module 3-4 is a conventional product, consisting of a servo motor 3-5, linear guides, a ball screw, and a slider. It is used to move the second probe 3-7 and the third probe 3-2. The servo motor 3-5 is an underwater motor and is encapsulated underwater. The probe clamp 3-3 is used to clamp the probes and ensure they are in close contact with the outer wall of the pipe. Its structural design allows for the probes to be moved up and down and rotated, enabling passive compensation to ensure complete contact with the pipe surface. The third probe 3-2, used for corrosion detection, is a conventional product and is fixed to the slider of the linear module 3-4 via the probe clamp 3-3. It is used to detect cracks, corrosion, and other defects on the pipe surface. There are two probes for weld inspection. One is fixed to the slider of the linear module 3-4 (arranged opposite the third probe 3-2) through the probe clamp 3-3, and the other is fixed to the end of the mounting bracket (or linear module 3-4). During inspection, the first probe 3-8 and the second probe 3-7 are placed on both sides of the weld for weld inspection. The structures of the three probes are generally the same, including a probe body and a wedge under the probe body. The probe body is used to convert electrical signals into acoustic signals, and the wedge is used to fit tightly against the pipe and transmit the acoustic signal of the probe body to the inner wall of the pipe. A water pipe connector is provided above the wedge for connecting to the coupling agent box 3-6 through a hose; a slot is provided at the bottom of the wedge for filling the bottom of the wedge with water. The coupling agent box 3-6 is filled with clean water, which acts as a coupling agent between the acoustic probe and the pipe surface.

[0052] like Figure 7 As shown, the probe clamp 3-3 comprises a rear support 3-3-1, a middle slide 3-3-2, a front support 3-3-3, and a horizontal support 3-3-4, which are used for passive compensation to keep the probe in close contact with the pipe surface. The middle slide 3-3-2 is fixed to the front support 3-3-3. The rear support 3-3-1 slidably engages with the middle slide 3-3-2, allowing it to slide up and down along the middle slide 3-3-2. The bottom of the rear support 3-3-1 is movably mounted to the horizontal support 3-3-4 using screws along the x-axis, allowing the horizontal support 3-3-4 to rotate about the x-axis. The probe is movably mounted to the horizontal support 3-3-4 using screws along the y' axis, allowing it to rotate along the y' axis. A spring creates a downward preload between the rear support 3-3-1 and the front support 3-3-3.

[0053] The specific method of use of the present invention is as follows:

[0054] (1) Preparations before launching

[0055] Before lowering to the seabed, the electric winch in the dry compartment is used to tighten the rope tied to the lifting lug 1-6, so that the left holding rail 1-2 and the right holding rail 1-8 are opened. At this time, the radial electric cylinder 4 is in a retracted state.

[0056] (2) Release operation after launching

[0057] After the dry tank is lowered to the submarine pipeline 5 and enclosed, the seawater in the tank is replaced with air. A winch is used to lower the nondestructive testing mechanism. After confirming that the openings of the left and right holding rails 1-2 and 1-8 are securely mounted on the pipeline, the winches on both sides are released to close the holding rails, and the electromagnets are energized to close the bottoms of the two holding rails.

[0058] (3) Weld inspection

[0059] The axial cylinder 2 extends until the weld to be inspected is located between the first probe 3-8 and the second probe 3-7. The radial cylinder 4 extends until the inspection system 3 is pressed against the pipe, and the weld is inspected using both probes. The inspection system 3 can fine-tune the position of the second probe 3-7 on the linear module 3-4. The rotary motor 1-5 drives the rotary table 1-4 in circumferential motion, driving the inspection system 3 to begin circumferential inspection of the weld.

[0060] (4) Corrosion detection

[0061] After the weld inspection is completed, the third probe 3-2 is used to perform circumferential movement in the same manner to detect the corrosion condition of the pipeline surface.

[0062] (5) Self-driven displacement

[0063] When the radial electric cylinder 4 presses the probe, the axial electric cylinder 2 is extended to drive the annular rail 1 to move axially along the surface of the pipeline, and then the next detection interval is detected.

[0064] (6) Mobile dry tank

[0065] After the non-destructive testing mechanism completes the inspection of all pipelines inside the dry chamber in a self-driven displacement manner, the dry chamber is opened and moved to the next workstation interval.

[0066] Then repeat the operations of steps (2) to (5), and after enclosing and replacing the air, perform weld inspection and corrosion inspection based on self-driven displacement again.

[0067] (7) Recovery detection device

[0068] Cut off the power to the electromagnet, tighten the winch and lift the nondestructive testing mechanism, then recover the entire dry cabin according to normal operations.

Claims

1. A trackless submarine pipeline non-destructive testing device, comprising an outer frame, a scanning cabin, and a scanning cabin pumping device; characterized in that: A self-propelled non-destructive testing mechanism is provided in the scanning cabin, and the non-destructive testing mechanism includes an annular holding rail, an axial electric cylinder, a testing mechanism and a radial electric cylinder; wherein, The annular holding rail is arranged around the pipe being measured and consists of symmetrically arranged semicircular left and right holding rails. The outer side of the annular holding rail has a spliced ​​annular rack and annular track, and at least three holding support wheels are evenly arranged along the circumference on its inner side. The rollers at the bottom of the holding support wheels are mounted on the annular holding rail through brackets and elastic components, and are used to hold the pipe being measured and assist the annular holding rail in moving axially along the pipe. The axial electric cylinder is arranged along the axial direction of the pipeline to be measured, and its cylinder body is mounted on the annular holding rail via a rotating platform. The top end of the telescopic rod is fixedly connected to the cylinder body of the radial electric cylinder. The rotating platform includes a pulley, a gear, and a rotary motor. The pulley is embedded in the annular track, the gear is meshed with the annular rack, and the end of the output shaft of the rotary motor is connected to the gear. The radial electric cylinder is arranged perpendicular to the axial electric cylinder, and its telescopic rod faces the central axis of the pipeline to be measured, with a detection mechanism fixedly installed at the top end. The detection mechanism includes a mounting frame, the upper portion of which is fixedly connected to the top end of the telescopic rod of the radial electric cylinder; a linear module is provided at the lower portion of the mounting frame and is arranged along the axial direction of the pipeline to be tested. The linear module includes a servo motor, a linear guide, a ball screw and a slider, and the slider is seated on the linear guide and driven by the ball screw to move; the detection mechanism includes multiple probes, including at least a first probe and a second probe for detecting welds, and a third probe for detecting corrosion; wherein the first probe is fixedly mounted on the mounting frame by a probe clamp, and the second probe and the third probe are each fixedly mounted on the same slider by a probe clamp; the first probe and the second probe are arranged opposite each other, and an adjustable distance is retained between them for detecting welds; The device performs inspection operations in the following manner: the telescopic rod of the axial electric cylinder is extended until the weld is located between the first and second probes; the telescopic rod of the radial electric cylinder is extended until the inspection system presses against the pipeline; the rotary table is driven by a rotary motor to perform circumferential movement, driving the inspection system to perform circumferential inspection of the weld; after the weld inspection is completed, the third probe is driven to perform circumferential movement in the same manner to inspect the corrosion condition of the pipeline surface; The device performs self-driven displacement in the following way: the probe in the radial electric cylinder detection mechanism is pressed against the pipe to be tested, and then the telescopic rod of the axial electric cylinder is extended, driving the annular holding rail to perform axial displacement along the pipe surface; and then the next detection interval is detected through the coordination of the actions of the radial and axial electric cylinders.

2. The device according to claim 1, characterized in that The tops of the left holding rail and the right holding rail are connected by a rotating shaft; electromagnets are respectively provided at the joints of the bottoms of the two for attracting and fixing the pipe when clamping it; lifting ears are respectively provided at the rotating shaft, the middle of the left holding rail, and the middle of the right holding rail for installing a rope for lifting or pulling.

3. The device according to claim 1, characterized in that A set of docking wheels is provided on the side surfaces of the two docking ends of the left holding rail and the right holding rail respectively; the docking wheels include a cam and a concave wheel and the shapes of the outer edges of the two cooperate with each other, playing a guiding role when the left holding rail and the right holding rail are closed.

4. The device according to claim 1, characterized in that The left holding rail and the right holding rail have the same main structure, both including two semicircular plates arranged alternately and several intermediate horizontal plates for connecting the two; a semicircular rack is arranged between the two semicircular plates, and one of the plates is used as a track for installing the rotating table; the clamping support wheel is installed on the intermediate horizontal plate.

5. The device according to claim 1, characterized in that The clamping support wheel includes a gas spring, a ball bearing and a bracket connected in sequence; the two rollers are installed side by side in the bracket and arranged along the axial direction of the measured pipeline; the gas spring is fixed on the annular holding rail, and can extend and contract along the radial direction of the measured pipeline while maintaining a constant extended state, and is used to realize a passive compensation function after the annular holding rail holds the pipeline; the roller can roll along the axial direction of the pipeline driven by the annular holding rail to reduce friction.

6. The device according to claim 1, characterized in that The rotating platform includes a clamping mounting base, on the side of which the cylinder body of the axial electric cylinder is fixed; the rotating motor is installed in the middle position of the clamping mounting base, the output shaft of the motor passes through the clamping mounting base, and the gear is fixed to the end of the output shaft; four pulleys are provided inside the clamping mounting base, with one group on each side of the output shaft of the rotating motor, and each group of pulleys is movably embedded in cooperation with each other on both sides of the annular track.

7. The device according to claim 1, characterized in that The probe clamp includes a rear support piece, a middle slide rail, a front support piece and a horizontal support piece; the front support piece is in a Z-shaped bend with a right angle, one of the vertical folded edges is fixed to the side of the slider or the mounting bracket by a screw, and the other vertical folded edge is fixedly connected to the middle slide rail; the rear support piece and the middle slide rail are in sliding cooperation and can slide up and down in the vertical direction; the bottom of the rear support piece is movably connected to the horizontal support piece by a screw in the x-axis direction, and the horizontal support piece can rotate around the x-axis; the probe is y’ The screw in the axial direction is movably connected to the horizontal support piece, and the probe can move around y’ The shaft rotates; the rear support plate and the front support plate are connected by a spring and form a downward preload force to provide passive compensation so that the probe can be tightly attached to the surface of the measured pipe.

8. The device according to claim 1, wherein the probe comprises a probe body and a wedge, the wedge being located below the probe body. The probe body is used to convert electrical signals into acoustic signals, and the wedge is used to closely adhere to the pipe and transmit the acoustic signals from the probe body to the inner wall of the pipe. The wedge is provided with a water pipe connector on the upper side and a slot on the bottom, which is connected to an internal channel. The water pipe connector is connected to a couplant box via a hose, and the couplant box is filled with clean water as a couplant.

9. The device according to claim 1, characterized in that The axial electric cylinder, radial electric cylinder, rotary motor, servo motor and electromagnet are respectively connected to a control host of the ultrasonic detection system arranged on the mother ship through cables.

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