Freely-rotatable super-long flexible pipe tensile experiment device

Abstract

The invention discloses an ultra-long flexible pipe tensile experiment device capable of freely rotating, and belongs to the technical field of ocean engineering equipment. The device comprises a first support, a second support and a third support which are quickly disassembled and connected through bolts, each support is provided with a supporting assembly and a transparent protective cover, and the length can be increased by increasing the second support. A hydraulic telescopic rod of the first support is connected with an experiment sample tube through a first flange plate, and a rotation angle measuring assembly of the third support is connected with the other end of the sample tube through a second flange plate and a universal joint, so that free rotation and angle measurement are realized. The first support is provided with a stretching length measuring assembly which moves along with the hydraulic telescopic rod to measure the length. The first support and the third support are matched with support compression measuring assemblies to monitor support deformation. The supporting assembly can adjust the height of the sample tube to guarantee horizontal stress. The device is simple in structure, detachable and adjustable in length, solves the problems that an existing device is limited in length, high in price and incapable of measuring the stretching rotation angle, and is adaptive to the stretching mechanical test of the ultra-long flexible pipe.

Description

Technical Field

[0001] This invention belongs to the field of marine engineering equipment technology, and in particular relates to a free-rotating ultra-long flexible tube tensile testing device, which is especially suitable for testing and inspection before marine oil and gas extraction and submarine pipeline laying. Background Technology

[0002] Unbonded marine flexible pipes are one of the key pieces of equipment for production, storage and offloading (PSA) semi-submersible platforms, serving as the sole channel connecting the subsea wellhead to the platform. Simultaneously, they play a crucial role in subsea oil and gas transportation and deep-sea resource development, making them an indispensable core piece of equipment in marine oil and gas engineering. When conducting mechanical performance tests on these flexible pipes, joints must be machined at both ends and equipped with specialized tooling. Furthermore, the length of the test sample pipe must be greater than twice the helical winding pitch of the tensile armor layer, significantly increasing the overall length of the test object.

[0003] In current practical testing of flexible tube tensile tests, several requirements have been placed on the experimental apparatus: First, due to the significant increase in overall length of the test sample tube after the addition of joints and tooling, the experimental apparatus needs to have sufficient length adaptability to meet the tensile testing requirements of ultra-long test objects; Second, with the increasing demand for cost reduction and efficiency improvement, as well as multi-scenario testing, there is a need for cost-effective and easily promoted dedicated experimental apparatus to adapt to the tensile testing scenarios of ultra-long flexible tubes; Third, based on the helical winding structural characteristics of flexible tubes, they will rotate during the tensile process. Therefore, the experimental apparatus needs to have the adaptability to free rotation, while accurately detecting multiple parameters such as tensile length and rotation angle to meet the multi-dimensional test data acquisition requirements.

[0004] Existing patented technologies mainly target multi-condition composite loading and simulation of real-world working conditions. For example, patent number CN202510639619 describes a composite loading test device, system, and method for non-bonded flexible pipelines. This innovatively integrates a tension mechanism and a bending mechanism. An axial tensile load can be applied by a first drive source, while a bending load perpendicular to the axial direction can be applied by a second drive source, achieving composite loading testing of tension and bending. This accurately simulates the complex mechanical conditions of flexible pipelines in marine environments. The device is equipped with a displacement measurement module and a bending radius measurement module. A axial displacement and bending direction displacement data are collected using a wire sensor and a displacement sensor, respectively, to calculate the axial stiffness and bending radius of the pipeline. The device, equipped with temperature and pressure control modules, can simulate the mechanical response of pipelines under high temperature and high pressure conditions. However, its base frame is a fixed structure and lacks the ability to extend its length. It can only be used to test flexible pipes of conventional length and cannot meet the testing needs of ultra-long flexible pipes with added joints, tooling, or specific length requirements. Furthermore, it does not consider the rotational characteristics of non-bonded flexible pipes during the tensile process due to the spiral winding structure, and does not design a corresponding free rotation adaptation structure and rotation angle measurement component. This makes it impossible to accurately capture the rotational parameters during the tensile process. In addition, it lacks a support compression displacement measurement and compensation mechanism, making it difficult to eliminate the impact of support deformation on the accuracy of test data during the experiment.

[0005] The composite pipe multi-condition test device with patent number CN202411430566 can perform comprehensive testing under multiple conditions, including single conditions such as internal pressure, tension, bending, and torsion, as well as composite conditions of arbitrary combinations. However, the device has a fixed length and cannot be extended. It can only adapt to conventional composite pipes of different lengths by sliding a slider along the guide rail, and it has no ability to adapt to ultra-long pipes. A multifunctional mechanical performance testing device for marine pipes based on flexible risers, patent number CN201910643359, can perform tests under five working conditions: internal pressure, external pressure, tension and compression, bending, and vibration. It is compatible with general marine flexible risers, but it does not consider the spiral winding structure of the flexible pipe. It will rotate during stretching, making it impossible to measure the rotation angle, and it cannot be adapted to flexible pipes of different lengths. A novel combined tensile and compressive bending test device for marine flexible pipes, patent number CN201710730792, can achieve multiple combined working conditions, but the length can only be adapted to conventional pipes by fine adjustment of the trolley, which cannot meet the testing requirements of ultra-long flexible pipes, and it does not have a measurement function designed for the rotation characteristics of flexible pipes during stretching.

[0006] In summary, existing patented technologies are currently unable to achieve functions such as adapting to ultra-long flexible pipes, accurately measuring the rotation angle during the stretching process, and compensating for support deformation. Therefore, there is an urgent need to design an ultra-long pipe stretching test device that can adapt to different length requirements, has a simple structure, is easy to operate, and is detachable. This would solve the aforementioned problems of existing equipment in terms of length adaptation, cost control, and parameter measurement, and would be of great significance for improving the mechanical testing system of core components of marine engineering equipment and supporting the high-quality development of the marine engineering equipment industry. Summary of the Invention

[0007] The purpose of this invention is to overcome the technical shortcomings of existing flexible tube tensile testing devices, such as limited length, high cost of specialized equipment, and inability to measure rotation angle during tensile testing. This invention provides a freely rotatable, ultra-long flexible tube tensile testing device. This device features adjustable length, convenient assembly and disassembly, and a simple structure. It can accurately measure the tensile length and rotation angle of the flexible tube, and can also compensate for the compression displacement of the support. It is suitable for tensile mechanical testing requirements of ultra-long flexible tubes of different lengths, reduces testing equipment costs, and improves the parameter detection system for flexible tube tensile testing.

[0008] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a freely rotatable ultra-long flexible tube tensile testing device, mainly composed of a support body, a power drive component, a support component, a parameter measurement component, and a support compression measurement component. These components work together to achieve the tensile testing and precise multi-parameter detection of the ultra-long flexible tube. The specific structure is as follows: The main body of the support system includes a first support, a second support, and a third support, which are connected and disassembled quickly via pins. The number of second supports can be flexibly increased according to the actual length of the experimental sample tube, allowing for free adjustment of the overall length of the device and adapting to the testing of ultra-long flexible tubes of different specifications. All supports are equipped with transparent protective covers, ensuring operational safety during the experiment and facilitating observation of the tensile state of the flexible tube. A hydraulic telescopic rod is used as the power source and is fixed to the first support. The output end of the hydraulic telescopic rod is fixedly connected to one end of the experimental sample tube (ultra-long flexible tube) through the first flange, providing a stable and controllable driving force for the stretching of the flexible tube and meeting the tensile force requirements of mechanical testing.

[0009] Each bracket is equipped with a support assembly, which includes a movable slider, a test sample tube support frame, and an adjusting bolt. The movable slider is slidably connected to the bracket via a slide rail, and its support position can be adjusted as the test sample tube is stretched. The test sample tube support frame is connected to the movable slider via the adjusting bolt, and its height can be freely adjusted by turning the adjusting bolt to adapt to the support requirements of flexible tubes of different diameters, ensuring that the test sample tube remains horizontal during the stretching process and avoiding the impact of uneven force on the test results.

[0010] The tensile length measuring component is mounted on the first support and consists of a pull wire sensor, a pull wire sensor bracket, a fixing rod, and connecting bolts. The pull wire sensor is fixed on the pull wire sensor bracket, which is connected to the first support via a slide rail. One end of the fixing rod is fixed to the pull wire sensor bracket via connecting bolts, and the other end is fixed to the hydraulic rod of the hydraulic telescopic rod, so that the tensile length measuring component can move synchronously with the hydraulic telescopic rod. The pull wire sensor accurately detects and records the real-time tensile length of the experimental sample tube.

[0011] The rotation angle measurement assembly is mounted on the third support and consists of a universal joint, an angle sensor, an angle sensor bracket, a timing belt, and gears. The universal joint is fixed on the third support, and the other end of the experimental sample tube is connected to the universal joint through the second flange, enabling the experimental sample tube to rotate freely during the stretching process. The angle sensor is fixed on the angle sensor bracket, which is fixedly connected to the third support. The angle sensor works with the gears through the timing belt to convert the rotation of the experimental sample tube into an electrical signal, accurately measuring and acquiring the rotation angle during the stretching process of the flexible tube.

[0012] The support compression measurement component is installed on the first and third supports respectively. The component has a built-in pull wire sensor, which can measure the compression distance of the support due to the tensile force during the stretching of the ultra-long flexible tube in real time. The data is used to compensate and correct the detection results of the stretching length measurement component, eliminate the influence of support deformation on the test data, and improve the accuracy of stretching length measurement.

[0013] Compared with the prior art, the beneficial effects of the present invention are reflected in the following aspects: Strong length adaptability: The bracket adopts a pin-type quick-disassembly structure, which can flexibly adjust the overall length of the device by increasing the number of second brackets. This completely solves the problem that the traditional tensile device has limited length and cannot adapt to the testing of ultra-long flexible tubes, and can adapt to the mechanical testing needs of flexible tubes of different specifications and lengths.

[0014] More comprehensive testing parameters: An innovative rotation angle measurement component is set up, which, combined with a universal joint, enables free rotation during the stretching process of the flexible tube. The rotation angle is accurately measured through the cooperation of an angle sensor, a synchronous belt, and gears. At the same time, a stretching length measurement component is added to achieve simultaneous detection of two parameters: stretching length and rotation angle. This fills the technical gap that existing devices cannot measure rotation angle, and provides complete data support for the mechanical property analysis of multi-layer composite structures of flexible tubes.

[0015] High accuracy of test data: The support compression measurement component can detect the compression displacement of the support due to force and compensate and correct the tensile length data, eliminating the measurement error caused by support deformation; the support component can be adjusted in height and move with the sample tube to ensure that the sample tube is subjected to horizontal force, further improving the accuracy of test data.

[0016] Low cost and high practicality: The overall device has a simple structural design, uses modular components, and has no complex precision parts. The manufacturing cost is far lower than that of a dedicated ultra-long flexible tube tensile testing device. At the same time, the bracket is easy to assemble and disassemble, and the operation process is simple. Experimental operations can be completed without professional technicians, which reduces the dual costs of equipment procurement and experimental operation. It is suitable for large-scale promotion and use by enterprises and research institutions.

[0017] Safe to use and easy to observe: All supports are equipped with transparent protective covers, which not only ensure the safety of equipment and operators during the experiment, but also allow for direct observation of the real-time status of the stretching and rotation of the flexible tube, making it easy to detect and deal with experimental abnormalities in a timely manner. Attached Figure Description

[0018] To make the content of this invention easier to understand, specific embodiments of the invention are described below in conjunction with... The accompanying drawings provide a further detailed description of the invention.

[0019] Figure 1 A schematic diagram of an ultra-long flexible tube tensile testing device that can rotate freely. Figure 2 This is a diagram of the bracket assembly. Figure 3 This is a schematic diagram of the experimental sample tube and support assembly. Figure 4 This is a schematic diagram of the rotation angle measuring component. Figure 5 This is a diagram of a universal joint. Figure 6 This is a schematic diagram of the tensile length measuring component. 1. First support; 2. Second support; 3. Third support; 4. Pin; 5. Support assembly; 6. Transparent protective cover; 7. Hydraulic telescopic rod; 8. Experimental sample tube; 9. Rotation angle measuring assembly; 10. Tensile length measuring assembly; 11. Support compression measuring assembly; 51. Moving slider; 52. Experimental sample tube support frame; 53. Adjusting bolt; 81. First flange; 82. Second flange; 83. Extra-long flexible tube; 91. Universal joint; 92. Angle sensor; 93. Angle sensor bracket; 94. Synchronous belt; 95. Gear; 101. Wire sensor; 102. Wire sensor bracket; 103. Fixing rod; 104. Connecting bolt Detailed Implementation

[0020] The following is in conjunction with the appendix Figure 1-6 The specific embodiments of the present invention will be described in detail below. These embodiments are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0021] Select the first support (1), the second support (2), and the third support (3) that are suitable for the length of the ultra-long flexible tube (82), and fix them in sequence by means of the pin (4) to form a complete test stand; if the length of the experimental tube exceeds the length of the basic assembly, the number of the second support (2) can be increased as needed, and the overall length of the device can be quickly extended by means of the pin (4) to ensure that the two ends of the tube can be effectively connected to the functional components of the first support (1) and the third support (3) respectively.

[0022] The hydraulic telescopic rod (7) is fixed at the preset installation position of the first bracket (1); the wire sensor bracket (102) of the stretch length measuring component (10) is slidably connected to the first bracket (1) through the slide rail, and fixed to the hydraulic rod of the hydraulic telescopic rod (7) through the fixing rod (103) and the connecting bolt (104) to ensure that the two move synchronously.

[0023] Install the rotation angle measuring component (9) on the third bracket (3), fix the universal joint (91) to the bracket preset interface, fix the angle sensor (92) through the angle sensor bracket (93), and connect the angle sensor (92) and the gear (95) through the synchronous belt (94) to ensure smooth transmission.

[0024] Install the support compression measurement component (11) at the designated positions of the first support (1) and the third support (3) respectively, and ensure that the detection direction of the built-in displacement sensor is consistent with the force compression direction of the support; assemble the support component (5) on the three supports respectively, the movable slider (51) is connected to the corresponding support through the slide rail, the experimental sample tube support frame (52) is assembled with the movable slider (51) through the adjusting bolt (53), and finally cover each support with a transparent protective cover (6) to complete the safety protection assembly.

[0025] One end of the extra-long flexible tube (82) is fixed and sealed to the output end of the hydraulic telescopic rod (7) through the first flange (81), and the other end is fixedly connected to the universal joint (91) on the third bracket (3) through the second flange (83) to ensure that the connection is firm and does not affect the free rotation of the sample tube.

[0026] According to the diameter of the experimental sample tube, tighten the adjusting bolt (53) of the support assembly (5) to adjust the height of the experimental sample tube support frame (52) so that the sample tube remains horizontal; slide the slider (51) to distribute the support assembly (5) evenly under the sample tube to avoid local force concentration and prevent the sample tube from falling off during the stretching process.

[0027] Start each measurement component and perform zero-point calibration on the built-in displacement sensors of the wire sensor (101), angle sensor (92) and bracket compression measurement component (11) to ensure that the measured value is zero in the initial state and eliminate system error.

[0028] According to the experimental requirements, the stretching rate, target stretching force or maximum stretching stroke of the hydraulic telescopic rod (7) is set, and the sampling frequency of the rotation angle measurement is specified to ensure that the data acquisition meets the test accuracy requirements; the hydraulic telescopic rod (7) is started, and the axial stretching force is applied according to the preset parameters to drive the experimental sample tube (8) to stretch gradually; during the stretching process: the stretching length measuring component (10) moves synchronously with the hydraulic telescopic rod (7), and the wire sensor (101) collects the stretching length data of the sample tube in real time; the experimental sample tube rotates due to the spiral winding structure, and the rotation is transmitted to the gear (95) through the universal joint (91), and the synchronous belt (94) drives the angle sensor (92) to operate, accurately collecting the rotation angle data; the bracket compression measuring component (11) monitors the compression distance of the first bracket (1) and the third bracket (3) due to the stretching force in real time and records the deformation data.

[0029] During the experiment, the stretching and rotation status of the sample tube is observed through the transparent protective cover (6). If any abnormalities such as sample tube displacement or component loosening are found, the operation of the hydraulic telescopic rod (7) is stopped immediately, and the rod is restarted after adjustment. If there is a risk of sample tube breakage, the experiment is terminated in time to ensure the safety of equipment and personnel. After the preset stretching parameters are reached, the hydraulic telescopic rod (7) is slowly reset, and the data acquisition of each measuring component is stopped simultaneously. Experimental data such as stretching length, rotation angle, and bracket deformation are saved. The experimental sample tube is disassembled, and the device is disassembled in the reverse order or kept in the assembled state for subsequent testing.

[0030] Based on the original length data collected by the pull wire sensor (101), and combined with the support deformation distance recorded by the support compression measurement component (11), compensation correction is performed. The formula is: corrected stretch length = original stretch length - support compression distance, thus eliminating the influence of support deformation on the measurement results. The actual rotation angle of the experimental tube is calculated by combining the electrical signal collected by the angle sensor (92) with the transmission ratio of the synchronous belt (94) and the gear (95), ensuring that the data accurately reflects the rotation characteristics of the tube during the stretching process.

Claims

1. A freely rotatable, ultra-long flexible tube tensile testing device, characterized in that: The apparatus includes a first support (1), a second support (2), a third support (3), a pin (4), a support assembly (5), a transparent protective cover (6), a hydraulic telescopic rod (7), an experimental sample tube (8), a rotation angle measuring assembly (9), a tensile length measuring assembly (10), and a support compression measuring assembly (11). The first support (1), the second support (2), and the third support (3) can be quickly connected and disconnected via the pin (4). The length of the experimental apparatus can also be increased by adding more second supports (2). Each of the three supports is equipped with a support assembly (5) and a transparent protective cover (6). The support assembly (5) can provide support for the experimental sample tube (8). A hydraulic telescopic rod is fixed on the first support (1). The hydraulic telescopic rod (7) is connected to the experimental sample tube (8) through the first flange (81). The rotation angle measuring component (9) is installed on the third support (3). The other end of the ultra-long flexible tube (82) is connected to the universal joint (91) through the second flange (83). The universal joint (91) is fixed on the third support (3), so that the experimental sample tube (8) can rotate freely and the rotation angle of the experimental sample tube (8) can be measured. The tensile length measuring component (10) is installed on the first support (1), so that the tensile length of the experimental sample tube (8) can be measured. The support compression measuring component (11) is installed on the first support (1) and the third support (3), so that the deformation measurement of the experimental platform during the experiment can be realized.

2. The rotatable ultra-long flexible tube tensile testing device according to claim 1, characterized in that: The support assembly (5) includes a movable slider (51), an experimental sample tube support frame (52), and an adjusting bolt (53). The movable slider (51) is connected to the corresponding bracket via a slide rail. The experimental sample tube support frame (52) is connected to the movable slider (51) via the adjusting bolt (53) and the height of the experimental sample tube (8) support frame (52) can be adjusted. The support assembly (5) can ensure that the experimental sample tube (8) remains horizontal during the stretching process, avoid affecting the test results due to uneven force, and also prevent the experimental sample tube (8) from being pulled off and falling to the ground, providing a certain safety guarantee.

3. The rotatable ultra-long flexible tube tensile testing device according to claim 1, characterized in that: The rotation angle measuring assembly (9) includes a universal joint (91), an angle sensor (92), an angle sensor bracket (93), a timing belt (94), and a gear (95). The universal joint (91) is fixed on the third bracket (3), the angle sensor (92) is fixed on the angle sensor bracket (93), the angle sensor bracket (93) is fixed on the third bracket (3), and the rotation angle of the experimental sample tube (8) is measured by the timing belt (94) and the gear (95).

4. The rotatable ultra-long flexible tube tensile testing device according to claim 1, characterized in that: The tensile length measuring component (10) includes a pull wire sensor (101), a pull wire sensor bracket (102), a fixing rod (103), and a connecting bolt (104). The pull wire sensor (101) is fixed on the pull wire sensor bracket (102), and the pull wire sensor bracket (102) is connected to the first bracket (1) via a slide rail. The fixing rod (103) is fixed on the pull wire sensor bracket (102) via the connecting bolt (104) and is fixed to the hydraulic telescopic rod (7). Therefore, the tensile length measuring component (10) can move with the hydraulic telescopic rod (7) and can measure the tensile length of the experimental sample tube (8).

5. The rotatable ultra-long flexible tube tensile testing device according to claim 1, characterized in that: The bracket compression measurement component (11) has a built-in displacement sensor, which is installed on the first bracket (1) and the third bracket (3) respectively, and is used to measure the deformation distance of the corresponding bracket when the tensile test sample tube (8) is used.

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