Device for testing pressure resistance of aviation memory alloy pipe joint

Abstract

The invention discloses an aviation memory alloy pipe joint pressure resistance testing device, which comprises a hydraulic system, a conduit experiment table and a control module, and is characterized in that the hydraulic system comprises an oil tank, a hydraulic pump, a motor and a pressure sensor, and the motor is used for driving the hydraulic pump; the pressure sensor is used for monitoring the pressure change in the pipeline in real time; the conduit test bench comprises a test container and a plurality of test pipeline assemblies, the test container is connected with the hydraulic pump, and at least one input channel and a plurality of output channels are configured in the test container; each test pipeline assembly comprises a test pipe and a control valve, one end of the test pipe is communicated with the corresponding output passage, and the other end of the test pipe is connected with the memory alloy pipe joint; the control valve is used for controlling opening and closing of the test tube; the control module is connected with the motor, the control valve and the pressure sensor, the output power of the motor and the opening degree of the control valve can be adjusted according to feedback signals of the pressure sensor, and therefore the hydraulic system can maintain the set pressure.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical engineering, and specifically to a pressure resistance performance testing device for an aviation memory alloy pipe joint. Background Art

[0002] NiTi memory alloy has unique shape memory characteristics and superelasticity, and is widely used in pipeline systems in the fields of aerospace, precision instruments, medical devices, and automotive manufacturing. During the forming and use processes of memory alloy pipe joints, controlled internal pressurization is required to achieve specific shape setting, performance evaluation, fatigue testing, or function restoration. Especially in engineering fields with high-precision and high-reliability requirements, strict requirements are put forward for pressure accuracy, pressure stability, and boost rate control during the pressurization process.

[0003] The traditional internal pressurization method for memory alloy pipe joints is usually manual pressurization, that is, an operator injects hydraulic oil into the joint interior through a manual hydraulic pump to make it deform or maintain under a certain pressure. In this traditional method, the following deficiencies exist: Manual pressurization depends on the operator's experience and feel, and it is difficult to precisely control the pressure value. Manual operation often fails to achieve such precision. Due to insufficient pressure accuracy, the setting quality of memory alloy pipe joints and the reliability of test data are affected.

[0004] In the traditional manual pressurization mode, it is difficult to maintain the set pressure for a long time or with high stability. When conducting long-term tests or shaping on the joint, the pressure may fluctuate due to the unevenness of manual operation, slight leakage of oil, or external disturbances. This instability will lead to inconsistent forming effects of the joint, or a decrease in the repeatability and credibility of test results.

[0005] Memory alloy materials are very sensitive to stress rate during deformation and phase change processes. Traditional manual pressurization cannot precisely control the boost rate. Once the pressurization process is too fast or too slow, it may lead to insufficient and uneven phase change of the memory alloy, affecting the forming effect and final performance.

[0006] In the existing technology, to improve the above problems, some researchers have tried to adopt semi-automatic methods, such as replacing the manual pump with a simple electric pump or restricting the maximum pressure through a mechanical pressure limiting device. However, most of these semi-automatic and mechanical pressure limiting means use electric pumps, lack feedback of the pressure value during the test, are prone to large pressure errors, and are more difficult to adjust the pressure value dynamically in real time during the test, resulting in difficulty in maintaining and controlling the pressure. Summary of the Invention

[0007] The purpose of the present invention is to provide a pressure resistance performance testing device for an aviation memory alloy pipe joint, which can keep the pressure stable near the target value for a long time.

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

[0009] A pressure resistance performance test device for an aviation memory alloy pipe joint, comprising: a hydraulic system, including: an oil tank for storing hydraulic oil; a hydraulic pump connected to the oil tank; a motor for driving the hydraulic pump, the output shaft of the motor being connected to the input shaft of the hydraulic pump; a pressure sensor disposed at the output end of the hydraulic pump for real-time monitoring of the pressure change in the pipeline; a conduit test bench, including: a test container internally configured with at least one input passage and a plurality of output passages, the input passage of which is connected to the output end of the hydraulic pump through a connecting pipe; a plurality of test pipe assemblies respectively corresponding to and connected to the plurality of output passages on the test container, and the plurality of test pipe assemblies respectively corresponding to a plurality of different types of memory alloy pipe joints, and the hydraulic oil is conveyed into the memory alloy pipe joints through the test pipe assemblies. Each of the test pipe assemblies includes: a test pipe, one end of which is communicated with the output passage of the test container, and the other end is connected to one end of the memory alloy pipe joint, and the other end of the memory alloy pipe joint is closed so that the hydraulic oil is continuously pressurized in the memory alloy pipe joint; a control valve disposed at the connection between the test container and the test pipe for controlling the opening and closing of the test pipe; a control module respectively connected to the motor, the control valve and the pressure sensor for receiving the feedback signal of the pressure sensor and adjusting the output power of the motor and the opening of the control valve according to the feedback signal to adjust the pressurization rate of the hydraulic system, so as to maintain the hydraulic system at a set pressure.

[0010] During the test, the high-precision pressure sensor and the motor are frequency-converted and regulated, and the pressure accuracy is controlled within ±0.01 MPa through closed-loop control. The reliability and consistency of the forming and test results of the memory alloy pipe joint are effectively improved through high-precision pressure regulation.

[0011] After reaching the set pressure, the control module can automatically adjust the rotation speed of the motor and the opening of the control valve to keep the pressure stable near the target value for a long time. Compared with the problem of easy pressure fluctuation caused by traditional manual pressurization, it can ensure that the memory alloy pipe joint completes phase change or deformation under a constant stress state, and improves the forming quality.

[0012] Through the coordinated control of the motor and the control valve, the linearity, adjustability and good repeatability of the pressure increase rate can be achieved. This enables the memory alloy material to be loaded under the optimal stress rate conditions, which is beneficial to more accurately study and utilize the phase change mechanism and performance characteristics of the memory alloy.

[0013] Moreover, the user can easily switch between different types of memory alloy pipe joints through the conduit test bench configured with a plurality of test pipe assemblies without frequent disassembly and assembly of components. The operation complexity is reduced, the risk of seal leakage caused by repeated assembly at the connection is reduced, and the experimental efficiency and safety are significantly improved.

[0014] Further, the connecting pipe is a 70 MPa high-pressure hose, and the test pipe is a 100 MPa high-pressure rubber hose. It maintains sealing under high pressure and high temperature conditions, prevents leakage, and ensures the normal operation and safety of the system.

[0015] Further, to ensure the purity of the test medium and improve the accuracy of the results, the test container further includes: an oil return passage, with both ends of the oil return passage connected to a first oil return pipe and a second oil return pipe respectively. The first oil return pipe is connected to the closed end of the shape memory alloy pipe joint, and the second oil return pipe communicates with the fuel tank. The size of the first oil return pipe corresponds to the size of the shape memory alloy pipe joint connected thereto; an oil return valve, arranged on the oil return passage, for controlling the opening and closing of the oil return passage. A pump is configured between the second oil return pipe and the fuel tank.

[0016] Further, the control center is externally connected to a display module for displaying real-time pressure data.

[0017] Further, the hydraulic system is also equipped with a hand pump.

[0018] Further, a liquid level sensor is provided in the fuel tank, and the liquid level sensor is connected to the control module.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. The present invention obtains the pressure change data in the pipeline monitored in real time by the pressure sensor through the control module, and adjusts the output power of the motor according to the feedback signal. Through closed-loop control, the pressure accuracy is controlled within ±0.01 MPa. This high-precision pressure regulation effectively improves the reliability and consistency of the forming and test results of the shape memory alloy pipe joint; after reaching the set pressure, the control module can automatically adjust the motor speed and the opening of the control valve to keep the pressure stable near the target value for a long time. Compared with the problem of easy pressure fluctuation caused by traditional manual pressurization, it can ensure that the shape memory alloy pipe joint completes phase change or deformation under a constant stress state, improving the forming quality; and through the coordinated control of the motor and the control valve, the linear, adjustable and repeatable pressure increase rate is realized. The shape memory alloy material is loaded under the optimal stress rate condition, which is conducive to more accurately studying and utilizing the phase change mechanism and performance characteristics of the shape memory alloy.

[0021] 2. The present invention provides a catheter test bench with multiple test pipe components, and the multiple test pipe components respectively correspond to multiple different models of shape memory alloy pipe joints. Through the catheter test bench of the present invention, users can easily switch between different models of shape memory alloy pipe joints without frequent disassembly and assembly of components. It reduces the operation complexity, reduces the risk of seal leakage caused by repeated assembly at the connection, and significantly improves the experimental efficiency and safety.

[0022] 3. The test container of the present invention is also provided with an oil return passage. Before the test experiment, the oil return valve is opened to empty the air bubbles in the pipeline and the oil fluid, ensuring the purity of the medium and the stability of the pressure reading, so as to make the experimental data more accurate, repeatable and easy to compare. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic structural diagram of the hydraulic system and the conduit test bench of the present invention.

[0024] Among them, 1. Oil tank, 2. Hydraulic pump, 3. Motor, 4. Pressure sensor, 5. Conduit test bench, 6. Test container, 7. Test pipe, 8. Control valve, 9. First oil return pipe, 10. Shape memory alloy pipe joint, 11. Oil return valve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following combines Figure 1 , and describes the specific embodiments of the present invention in detail. In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention 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 should not be construed as a limitation of the present invention.

[0026] The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features; in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0027] Embodiment

[0028] As Figure 1As shown in the figure, a pressure resistance performance test device for an aviation memory alloy pipe joint includes a hydraulic system, a conduit test bench, and a control module. The hydraulic system includes an oil tank 1, a hydraulic pump 2, an electric motor 3, and a pressure sensor 4. The oil tank 1 is used for storing hydraulic oil; the hydraulic pump 2 is connected to the oil tank 1; the electric motor 3 is used for driving the hydraulic pump 2, and the output shaft of the electric motor 3 is connected to the input shaft of the hydraulic pump 2 through a coupling; the pressure sensor 4 is arranged at the output end of the hydraulic pump 2 and is used for real-time monitoring of the pressure change in the pipeline. The conduit test bench 5 includes a test container 6, a plurality of test pipeline components, and control valves. The test container 6 is internally provided with at least one input passage and a plurality of output passages, and its input passage is connected to the output end of the hydraulic pump 2 through a connecting pipe; the plurality of test pipeline components are respectively connected corresponding to the plurality of output passages on the test container 6, and the plurality of test pipeline components respectively correspond to a plurality of memory alloy pipe joints 10 of different models. The hydraulic oil is conveyed into the memory alloy pipe joint 10 through the test pipeline components. Each test pipeline component includes a test pipe 7, one end of which is communicated with the output passage of the test container 6, and the other end is connected to one end of the memory alloy pipe joint 10. The other end of the memory alloy pipe joint 10 is closed so that the hydraulic oil is continuously pressurized in the memory alloy pipe joint 10; the control valve 8 is arranged at the communication position between the test container 6 and the test pipe 7 and is used for controlling the opening and closing of the test pipe 7. The control module is respectively connected to the electric motor 3, the control valve 8, and the pressure sensor 4, and is used for receiving the feedback signal of the pressure sensor 4 and adjusting the output power of the electric motor 3 and the opening degree of the control valve 8 according to the feedback signal so as to adjust the pressurization rate of the hydraulic system, thereby enabling the hydraulic system to maintain a set pressure.

[0029] During the test, the high-precision pressure sensor 4 and the electric motor 3 are frequency-controlled, and the pressure accuracy is controlled within ±0.01 MPa through closed-loop control. The reliability and consistency of the forming and test results of the memory alloy pipe joint 10 are effectively improved through high-precision pressure regulation.

[0030] After reaching the set pressure, the control module can automatically adjust the rotation speed of the electric motor 3 and the opening degree of the control valve 8 to keep the pressure stable near the target value for a long time. Compared with the problem of easy pressure fluctuation caused by traditional manual pressurization, it can ensure that the memory alloy pipe joint 10 completes phase change or deformation under a constant stress state and improves the forming quality.

[0031] Through the coordinated control of the electric motor 3 and the control valve 8, the linearity, adjustability, and good repeatability of the pressure increase rate can be achieved. This enables the memory alloy material to be loaded under the optimal stress rate conditions, which is beneficial to more accurately study and utilize the phase change mechanism and performance characteristics of the memory alloy.

[0032] Moreover, the user can easily switch between memory alloy pipe joints 10 of different models through the conduit test bench 5 configured with multiple test pipeline components, without the need to frequently disassemble and assemble components. This reduces the operation complexity and the risk of seal leakage caused by repeated assembly at the connection, significantly improving the experimental efficiency and safety.

[0033] In some embodiments, the connecting pipe is a 70MPa high-pressure hose, and the test pipe 7 is a 100MPa high-pressure rubber hose. It maintains sealing under high-pressure and high-temperature conditions to prevent leakage and ensure the normal operation and safety of the system.

[0034] In some embodiments, the test container 6 further includes: an oil return passage and an oil return valve. The two ends of the oil return passage are respectively connected to the first oil return pipe 9 and the second oil return pipe. The first oil return pipe 9 is connected to the closed end of the memory alloy pipe joint 10, the second oil return pipe communicates with the fuel tank 1, and the size of the first oil return pipe 9 corresponds to the size of the memory alloy pipe joint 10 connected thereto; the oil return valve 11 is arranged on the oil return passage to control the opening and closing of the oil return passage. A pump is configured between the second oil return pipe and the fuel tank 1.

[0035] In some embodiments, there are three types of test pieces, and the outer diameters of the pipelines are respectively and The test is carried out at ambient temperature. Before applying pressure, open the oil return valve 11 to connect the first oil return pipe 9 with the test container 6. Open the oil return valve before the test experiment to drain the air bubbles in the pipeline and the oil, ensuring the purity of the medium and the stability of the pressure reading. During the test, close the oil return passage to seal the end of the memory alloy joint 10, so that the hydraulic oil continuously pressurizes inside the memory alloy pipe joint 10.

[0036] In some embodiments, the control center is externally connected to a display module for displaying real-time pressure data.

[0037] In some embodiments, the hydraulic system is also configured with a hand pump as a backup.

[0038] In some embodiments, a liquid level sensor is provided inside the fuel tank 1, and the liquid level sensor is connected to the control module to monitor the oil quantity inside the fuel tank 1 in real time.

[0039] The above-disclosed are only several preferred specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto, and any changes that can be thought of by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A pressure resistance test device for aviation memory alloy pipe joints, characterized in that: include: A hydraulic system comprises: an oil tank (1) for storing hydraulic oil; a hydraulic pump (2) connected to the oil tank (1); a motor (3) for driving the hydraulic pump (2), wherein the output shaft of the motor (3) is connected to the input shaft of the hydraulic pump (2); and a pressure sensor (4) arranged at the output end of the hydraulic pump (2) for real-time monitoring of pressure changes in a pipeline. A catheter test bench (5) comprises: a test container (6) having at least one input passage and a plurality of output passages disposed therein, wherein the input passage is connected to the output end of the hydraulic pump (2) via a connecting pipe; a plurality of test pipe assemblies respectively connected to the plurality of output passages on the test container (6), and the plurality of test pipe assemblies respectively correspond to a plurality of memory alloy pipe joints (10) of different models, and hydraulic oil is transported to the memory alloy pipe joint (10) via the test pipe assemblies, wherein each of the test pipe assemblies comprises: a test pipe (7) having one end connected to the output passage of the test container (6) and the other end connected to one end of the memory alloy pipe joint (10), and the other end of the memory alloy pipe joint (10) being closed so that the hydraulic oil is continuously pressurized in the memory alloy pipe joint (10); and a control valve (8) disposed at the connection between the test container (6) and the test pipe (7) and used to control the opening and closing of the test pipe (7); The control module is connected to the motor (3), the control valve (8) and the pressure sensor (4) respectively, and is used to receive a feedback signal from the pressure sensor (4), and adjust the output power of the motor (3) and the opening of the control valve (8) according to the feedback signal, so as to adjust the pressurization rate of the hydraulic system, thereby maintaining the set pressure of the hydraulic system.

2. The pressure resistance performance testing device for aviation memory alloy pipe joints according to claim 1 is characterized in that: The connecting pipe is a 70MPa high-pressure hose, and the test pipe (7) is a 100MPa high-pressure rubber hose.

3. The pressure resistance performance testing device for aviation memory alloy pipe joints according to claim 1 is characterized in that: The test container (6) further comprises: an oil return passage, the two ends of which are respectively connected to a first oil return pipe (9) and a second oil return pipe, the first oil return pipe (9) being connected to a closed end of a memory alloy pipe joint (10), the second oil return pipe being connected to an oil tank (1), the size of the first oil return pipe (9) corresponding to the size of the memory alloy pipe joint (10) connected thereto; and an oil return valve (11) arranged on the oil return passage and used for controlling the opening and closing of the oil return passage.

4. The pressure resistance performance testing device for aviation memory alloy pipe joints according to claim 3 is characterized in that: A pump is arranged between the second oil return pipe and the oil tank (1).

5. The pressure resistance performance testing device for aviation memory alloy pipe joints according to claim 1, characterized in that: The control center is externally connected to a display module for displaying real-time pressure data.

6. The pressure resistance performance testing device for aviation memory alloy pipe joints according to claim 1, characterized in that: The hydraulic system is also equipped with a hand pump.

7. The pressure resistance performance testing device for aviation memory alloy pipe joints according to claim 1, characterized in that: A liquid level sensor is provided in the oil tank (1), and the liquid level sensor is connected to the control module.

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