Pipe service behavior evaluation device and use method thereof

Abstract

The invention discloses a pipe service behavior evaluation device and a use method thereof. The pipe service behavior evaluation device comprises an autoclave, a fretting wear loading mechanism, a stress corrosion test mechanism, a fixing mechanism and a temperature and pressure control system. According to the pipe service behavior evaluation device, the test pipe is arranged in the high-pressure kettle, the temperature and pressure of water in the high-pressure kettle are controlled through the temperature and pressure control system, the test pipe can be tested in a high-temperature and high-pressure water environment, and micro-amplitude vibration is applied to the test pipe through the fretting wear loading mechanism; a stress corrosion load is applied to the test pipe through the stress corrosion test mechanism, so that the service behavior evaluation of the test pipe in a high-temperature and high-pressure water environment under the synergistic effect of fretting wear and stress corrosion can be realized.

Description

Technical Field

[0001] The invention relates to the field of nuclear power plant pipe service behavior testing, and in particular to a pipe service behavior evaluation device and a use method thereof. Background Art

[0002] In nuclear power plants, components such as steam generator heat transfer tubes and core neutron flux measurement finger sleeves are in harsh service environments. They are not only subject to corrosion and stress from high-temperature and high-pressure water, but also suffer from wear between them and the supporting parts due to the flow and vibration. Therefore, they face the problem of coordinated failure due to wear and stress corrosion cracking in long-term service. At present, there are many evaluation equipment and methods for single mechanisms of stress corrosion and wear for heat transfer tubes, such as the national standard "GBT 15970.7-2017 Corrosion stress corrosion test for metals and alloys Part 7: Slow strain rate test", which stipulates the slow strain rate tensile test method. However, there are few test devices and evaluation methods for the service behavior of metal materials under the synergistic effect of wear and stress corrosion. For example, Chinese patent publication No. CN110940605A discloses a test device for the coupled effect of wear, stress and corrosion on heat transfer tubes and a service behavior evaluation method for heat transfer tubes. Based on the vertical stress loading of the C-type ring and the micro-motion wear loading of the horizontal compression, the coupling effect of wear and stress corrosion cracking is realized, and the wear-stress-corrosion coupling test process and evaluation method are established accordingly. However, the test device and evaluation method realize the circumferential stress loading of the heat transfer tube, and the cracking direction is circumferential, and the axial direction is not subjected to stress. Therefore, it is impossible to evaluate the axial stress and wear. Service behavior of pipes under the action of wear coupling; Chinese patent publication number CN117664774A discloses a test device and quantitative evaluation method for realizing stress-wear-corrosion coupling environment. A method of applying tensile stress by spring compression and applying unilateral downward pressure wear in the vertical direction is adopted to develop a wear, stress and corrosion coupling test device, and the interaction between wear, corrosion and stress is analyzed based on this. However, the test device and evaluation method realize the stress-wear-corrosion coupling effect research in an open normal temperature and pressure environment, and the wear acts on one side of the sample, which is not suitable for the service behavior evaluation of components such as steam generator heat transfer tubes in nuclear power plants in high temperature and high pressure water environment. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a pipe service behavior evaluation device and a method for using the same.

[0004] The technical solution adopted by the present invention to solve the technical problem is: constructing a pipe service behavior evaluation device, which includes an autoclave, a fretting wear loading mechanism, a stress corrosion test mechanism, a fixing mechanism and a temperature and pressure control system;

[0005] The autoclave is used to contain test pipes;

[0006] The fretting wear loading mechanism is connected to the autoclave and is used to apply micro-vibration to the test pipe;

[0007] The stress corrosion testing mechanism is connected to the autoclave and is used to apply stress corrosion load to the test pipe;

[0008] The fixing mechanism is installed in the autoclave and is used to fix the position of the test tube;

[0009] The temperature and pressure control system is used to control the temperature and pressure of water in the autoclave.

[0010] In some embodiments, the fretting wear loading mechanism includes a fretting wear loader, a fretting wear connecting rod, a micro-vibration connecting plate, a micro-vibration connecting rod, and a fretting wear press head;

[0011] The two ends of the fretting wear connecting rod are respectively connected to the fretting wear loader and the micro-vibration connecting plate, and the fretting wear connecting rod is fixedly connected to the autoclave;

[0012] The two ends of the micro-vibration connecting rod are respectively connected to the micro-vibration connecting plate and the micro-motion wear pressure head, and the micro-motion wear pressure head is used to contact the side wall of the test pipe.

[0013] In some embodiments, the number of the micro-vibration connecting rod and the number of the micro-motion wear indenter are both at least two.

[0014] In some embodiments, the stress corrosion testing mechanism includes a stress corrosion tester, a stress corrosion tester connecting rod, and a lower pipe clamp;

[0015] The two ends of the stress corrosion tester connecting rod are respectively connected to the stress corrosion tester and the lower fixture of the pipe, and the stress corrosion tester connecting rod is fixedly connected to the autoclave;

[0016] The lower pipe clamp is used to contact the lower end surface of the test pipe.

[0017] In some embodiments, the fretting wear connecting rod is connected to the autoclave via a first seal;

[0018] The stress corrosion testing machine connecting rod is connected to the autoclave through a second sealing member.

[0019] In some embodiments, the fixing mechanism includes a fixing connecting rod, a fixing connecting plate and a clamp on the pipe;

[0020] The fixed connecting rod is fixedly installed in the autoclave, and the fixed connecting plate is fixedly connected to the fixed connecting rod;

[0021] The upper pipe clamp is fixedly connected to the fixed connecting plate, and the lower pipe clamp is used to contact the upper end surface of the test pipe.

[0022] In this embodiment, a method for using the pipe service behavior evaluation device is also constructed, which is based on the pipe service behavior evaluation device and includes the steps of:

[0023] S1. Install the test pipe on the pipe service behavior evaluation device;

[0024] S2, start the temperature and pressure control system to make the autoclave reach a preset pressure and a predetermined temperature;

[0025] S3, start the stress corrosion tester and perform the test according to the preset stress corrosion test procedure;

[0026] S4, starting the fretting wear loader so that the fretting wear indenter performs a slight vibration with preset vibration parameter information relative to the test pipe;

[0027] S5, first stop the fretting wear loader, then stop the stress corrosion tester, and finally use the temperature and pressure control system to reduce the temperature and pressure, and then take samples for analysis.

[0028] In some embodiments, step S1 includes:

[0029] S11, connecting and fixing the fretting wear connecting rod to the fretting wear loader, and connecting the two ends of the stress corrosion tester connecting rod to the stress corrosion tester and the pipe lower fixture respectively;

[0030] S12, fixedly connecting the fixed connecting rod to the autoclave, fixedly connecting the fixed connecting plate to the fixed connecting rod, and then fixedly connecting the pipe clamp to the fixed connecting plate, and installing the test pipe on the pipe clamp;

[0031] S13, fixing the connection rod of the stress corrosion testing machine to the autoclave, and fixing the position of the test pipe by using the lower pipe clamp and the upper pipe clamp;

[0032] S14, the micro-wear connecting rod is fixedly connected to the autoclave, and then the micro-vibration connecting plate, the micro-vibration connecting rod and the micro-wear pressure head are installed in sequence, and the load of the micro-vibration pressure head is adjusted to make the test pipe reach a preset clamping force.

[0033] In some embodiments, in step S3, the stress corrosion load types applied by the stress corrosion tester to the test pipe include constant load, slow strain rate tensile load and fatigue load.

[0034] In some embodiments, in step S4, the vibration parameter information includes amplitude, frequency and waveform.

[0035] The implementation of the present invention has the following beneficial effects: the pipe service behavior evaluation device can test the test pipe in a high-temperature and high-pressure water environment by placing the test pipe in an autoclave and controlling the temperature and pressure of the water in the autoclave through a temperature and pressure control system, and applies micro-vibration to the test pipe through a fretting wear loading mechanism, and applies stress corrosion load to the test pipe through a stress corrosion testing mechanism, so as to realize the service behavior evaluation of the test pipe in a high-temperature and high-pressure water environment under the synergistic effect of fretting wear and stress corrosion. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solution of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only show certain embodiments of the present invention and should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work. In the drawings:

[0037] Figure 1 Schematic diagram of the structure of a pipe service behavior evaluation device in some embodiments of the present invention. DETAILED DESCRIPTION

[0038] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific embodiments of the present invention are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "up", "down", "left", "right", "longitudinal", "horizontal", "vertical", "horizontal", "top", "bottom", "inside", "outside", "head", "tail", etc. are based on the directions or positional relationships shown in the accompanying drawings, are constructed and operated in a specific direction, and are only for the convenience of describing the present technical solution, rather than indicating that the device or element referred to must have a specific direction, and therefore cannot be understood as a limitation to the present invention.

[0039] It should also be noted that, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there may be one or more intermediate elements. The terms "first", "second", "third", etc. are only for the convenience of describing the present technical solution, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", "third", etc. can explicitly or implicitly include one or more of the features. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0040] See also Figure 1 , is a pipe service behavior evaluation device in some embodiments of the present invention, which includes an autoclave 1, a fretting wear loading mechanism 2, a stress corrosion test mechanism 3, a fixing mechanism 4 and a temperature and pressure control system. The autoclave 1 is used to accommodate a test pipe 5, and the autoclave 1 may be loaded with water; the fretting wear loading mechanism 2 is connected to the autoclave 1 and is used to apply micro-vibration to the test pipe 5; the stress corrosion test mechanism 3 is connected to the autoclave 1 and is used to apply stress corrosion load to the test pipe 5; the fixing mechanism 4 is installed in the autoclave 1 and is used to fix the position of the test pipe 5; the temperature and pressure control system is used to control the temperature and pressure of the water in the autoclave 1.

[0041] It can be understood that the pipe service behavior evaluation device can enable the test pipe 5 to be tested in a high-temperature and high-pressure water environment by placing the test pipe 5 in the autoclave 1 and controlling the temperature and pressure of the water in the autoclave 1 through a temperature and pressure control system, and applying micro-vibration to the test pipe 5 through the fretting wear loading mechanism 2 and applying stress corrosion load to the test pipe 5 through the stress corrosion testing mechanism 3, so as to realize the service behavior evaluation of the test pipe 5 in a high-temperature and high-pressure water environment under the synergistic effect of fretting wear and stress corrosion.

[0042] The micro-wear loading mechanism 2 includes a micro-wear loader 21, a micro-wear connecting rod 22, a micro-vibration connecting plate 23, a micro-vibration connecting rod 24 and a micro-wear pressure head 25. The two ends of the micro-wear connecting rod 22 are respectively connected to the micro-wear loader 21 and the micro-vibration connecting plate 23, and the micro-wear connecting rod 22 is fixedly connected to the autoclave 1, and the two ends of the micro-vibration connecting rod 24 are respectively connected to the micro-vibration connecting plate 23 and the micro-wear pressure head 25, and the micro-wear pressure head 25 is used to contact the side wall of the test pipe 5. The micro-wear loader 21 can apply micro-vibration with precise control of parameters such as amplitude, frequency, and waveform. The micro-wear pressure head 25 can contact the test pipe 5, and the pressing force between the micro-wear pressure head 25 and the test pipe 5 can be adjusted by adjusting the relative position of the micro-vibration connecting rod 24 relative to the micro-vibration connecting plate 23. The micro-vibration output by the micro-motion wear loader 21 can be transmitted to the test pipe 5 along the micro-motion wear connecting rod 22 , the micro-vibration connecting plate 23 , the micro-vibration connecting rod 24 and the micro-motion wear pressure head 25 in sequence.

[0043] Further, the number of the micro-vibration connecting rod 24 and the micro-motion wear head 25 is at least two. Preferably, the at least two micro-vibration connecting rods 24 and the micro-motion wear head 25 are symmetrically arranged about the central axis of the micro-motion wear connecting rod 22. The micro-motion wear connecting rod 22 is connected to the autoclave 1 through a first seal to prevent leakage of high-temperature and high-pressure water.

[0044] The stress corrosion test mechanism 3 includes a stress corrosion tester 31, a stress corrosion tester connecting rod 32 and a lower pipe clamp 33. The two ends of the stress corrosion tester connecting rod 32 are respectively connected to the stress corrosion tester 31 and the lower pipe clamp 33, and the stress corrosion tester connecting rod 32 is fixedly connected to the autoclave 1, and the lower pipe clamp 33 is used to contact the lower end surface of the test pipe 5. Among them, the stress corrosion tester 31 can apply stress corrosion loads such as constant load, slow strain rate tensile load, fatigue load and other stress corrosion loads, so that the test pipe 5 can be subjected to axial stress. The stress corrosion tester connecting rod 32 transmits the stress corrosion load output by the stress corrosion tester 31 to the lower pipe clamp 33. And the stress corrosion tester connecting rod 32 is connected to the autoclave 1 through a second seal to prevent leakage of high-temperature and high-pressure water.

[0045] Furthermore, the fixing mechanism 4 includes a fixed connecting rod 41, a fixed connecting plate 42 and a pipe upper clamp 43. The fixed connecting rod 41 is fixedly installed in the autoclave 1, the fixed connecting plate 42 is fixedly connected to the fixed connecting rod 41, the pipe upper clamp 43 is fixedly connected to the fixed connecting plate 42, and the pipe lower clamp 33 is used to contact the upper end surface of the test pipe 5. The number of the fixed connecting rods 41 is preferably four, which can ensure sufficient rigidity and no deformation during the test. The pipe lower clamp 33 and the pipe upper clamp 43 are used together to fix the position of the test pipe 5.

[0046] In this embodiment, a method for using the pipe service behavior evaluation device is also constructed, which is based on the above-mentioned pipe service behavior evaluation device and includes the steps of:

[0047] S1. Installing the test pipe 5 on the pipe service behavior evaluation device;

[0048] S2, start the temperature and pressure control system to make the autoclave 1 reach a preset pressure and a predetermined temperature;

[0049] S3, starting the stress corrosion tester 31, and performing the test according to a preset stress corrosion test procedure;

[0050] S4, starting the fretting wear loader 21, so that the fretting wear indenter 25 performs a slight vibration with respect to the test pipe 5 according to the preset vibration parameter information;

[0051] S5, first stop the fretting wear loader 21, then stop the stress corrosion tester 31, and finally use the temperature and pressure control system to reduce the temperature and pressure, and then take samples for analysis.

[0052] Specifically, in step S2 to step S5, it can be understood that, during the test, the temperature and pressure control system is first started to make the autoclave 1 reach the preset pressure and the predetermined temperature. Then the stress corrosion tester 31 is started, and the test is performed according to the preset stress corrosion test program, and then the micro-motion wear loader 21 is started, so that the micro-motion wear pressure head 25 performs a slight vibration with respect to the test pipe 5 according to the preset vibration parameter information. When the test is completed, the micro-motion wear loader 21 is stopped first, and then the stress corrosion tester 31 is stopped, and finally the temperature and pressure are reduced by using the temperature and pressure control system, and then samples are taken for analysis. The wear test is stopped first because the wear test is set according to the number of cycles, and it stops automatically after the set number of cycles. Stress corrosion will not stop until the wear cycle is reached. The temperature is lowered first because the water must be in a liquid state. If the pressure is lowered first, the water will boil.

[0053] When conducting the test analysis, the focus is on the initiation of stress corrosion cracks in the wear area. Through pure stress corrosion tests without fretting wear, pure wear tests without stress corrosion, and synergistic tests of fretting wear and stress corrosion under different conditions, the mechanism of failure of the test pipe 5 caused by the synergistic effect of fretting wear and stress corrosion can be analyzed.

[0054] In addition, in step S3, the stress corrosion load types applied by the stress corrosion tester 31 to the test pipe 5 include: constant load, slow strain rate tensile load and fatigue load. In step S4, the vibration parameter information includes amplitude, frequency and waveform.

[0055] Furthermore, step S1 includes:

[0056] S11, connect and fix the fretting wear connecting rod 22 to the fretting wear loader 21, and connect the two ends of the stress corrosion tester connecting rod 32 to the stress corrosion tester 31 and the lower pipe fixture 33 respectively;

[0057] S12, fixedly connecting the fixed connecting rod 41 to the autoclave 1, fixedly connecting the fixed connecting plate 42 to the fixed connecting rod 41, and then fixedly connecting the pipe upper clamp 43 to the fixed connecting plate 42, and installing the test pipe 5 on the pipe upper clamp 43;

[0058] S13, the stress corrosion test machine connecting rod 32 is fixedly connected to the autoclave 1, and the position of the test pipe 5 is fixed by the lower pipe clamp 33 and the upper pipe clamp 43;

[0059] S14, the micro-motion wear connecting rod 22 is fixedly connected to the autoclave 1, and then the micro-vibration connecting plate 23, the micro-vibration connecting rod 24 and the micro-motion wear pressure head 25 are installed in sequence, and the load of the micro-motion wear pressure head 25 is adjusted to make the test pipe 5 reach a preset size of the clamping force.

[0060] It can be understood that in step S1, the fixing mechanism 4 is first installed as a whole in the autoclave 1, and then the test pipe 5 and the stress corrosion test mechanism 3 are installed, and finally the fretting loading mechanism 2 is installed. By adjusting the load of the fretting pressure head 25, the test pipe 5 reaches a preset clamping force to complete the fixation of the test pipe 5 before the start of the test and the installation and fixation of each component.

[0061] It can be understood that the above embodiments only express the preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the patent scope of the present invention. It should be pointed out that, for ordinary technicians in this field, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should belong to the scope covered by the claims of the present invention.

Claims

1. A pipe service behavior evaluation device, characterized in that: It comprises an autoclave (1), a micro-wear loading mechanism (2), a stress corrosion testing mechanism (3), a fixing mechanism (4) and a temperature and pressure control system; The autoclave (1) is used to accommodate the test pipe (5); The micro-motion wear loading mechanism (2) is connected to the autoclave (1) and is used to apply micro-vibration to the test pipe (5); The stress corrosion test mechanism (3) is connected to the autoclave (1) and is used to apply stress corrosion load to the test pipe (5); The fixing mechanism (4) is installed in the autoclave (1) and is used to fix the position of the test tube (5); The temperature and pressure control system is used to control the temperature and pressure of the water in the autoclave (1).

2. The pipe service behavior evaluation device according to claim 1, characterized in that: The fretting wear loading mechanism (2) comprises a fretting wear loader (21), a fretting wear connecting rod (22), a micro-vibration connecting plate (23), a micro-vibration connecting rod (24) and a fretting wear pressure head (25); The two ends of the fretting wear connecting rod (22) are respectively connected to the fretting wear loader (21) and the micro-vibration connecting plate (23), and the fretting wear connecting rod (22) is fixedly connected to the autoclave (1); The two ends of the micro-vibration connecting rod (24) are respectively connected to the micro-vibration connecting plate (23) and the micro-motion wear head (25), and the micro-motion wear head (25) is used to contact the side wall of the test pipe (5).

3. The pipe service behavior evaluation device according to claim 2, characterized in that: The number of the micro-vibration connecting rod (24) and the number of the micro-motion wear pressure head (25) are both at least two.

4. The pipe service behavior evaluation device according to claim 2, characterized in that: The stress corrosion testing mechanism (3) comprises a stress corrosion testing device (31), a stress corrosion testing device connecting rod (32) and a lower pipe clamp (33); The two ends of the stress corrosion test machine connecting rod (32) are respectively connected to the stress corrosion tester (31) and the lower pipe clamp (33), and the stress corrosion test machine connecting rod (32) is fixedly connected to the autoclave (1); The lower pipe clamp (33) is used to contact the lower end surface of the test pipe (5).

5. The pipe service behavior evaluation device according to claim 4, characterized in that: The micro-motion wear connecting rod (22) is connected to the autoclave (1) via a first sealing member; The stress corrosion testing machine connecting rod (32) is connected to the autoclave (1) via a second sealing member.

6. The pipe service behavior evaluation device according to claim 4, characterized in that: The fixing mechanism (4) comprises a fixing connecting rod (41), a fixing connecting plate (42) and a pipe upper clamp (43); The fixed connecting rod (41) is fixedly installed in the autoclave (1), and the fixed connecting plate (42) is fixedly connected to the fixed connecting rod (41); The upper pipe clamp (43) is fixedly connected to the fixed connection plate (42), and the lower pipe clamp (33) is used to contact the upper end surface of the test pipe (5).

7. A method for using a pipe service behavior evaluation device, which is based on the pipe service behavior evaluation device according to any one of claims 1 to 6, characterized in that: Includes steps: S1. Installing the test pipe (5) on a pipe service behavior evaluation device; S2, starting the temperature and pressure control system to allow the autoclave (1) to reach a preset pressure and a predetermined temperature; S3, starting the stress corrosion tester (31), and performing the test according to a preset stress corrosion test procedure; S4, starting the fretting wear loader (21), so that the fretting wear pressure head (25) performs a micro-vibration with preset vibration parameter information relative to the test pipe (5); S5, first stop the fretting wear loader (21), then stop the stress corrosion tester (31), and finally use the temperature and pressure control system to reduce the temperature and pressure, and then take samples for analysis.

8. The method for using the pipe service behavior evaluation device according to claim 7, characterized in that: The step S1 comprises: S11, connecting and fixing the fretting wear connecting rod (22) to the fretting wear loader (21), and connecting the two ends of the stress corrosion tester connecting rod (32) to the stress corrosion tester (31) and the lower pipe clamp (33) respectively; S12, fixedly connecting the fixed connecting rod (41) to the autoclave (1), fixedly connecting the fixed connecting plate (42) to the fixed connecting rod (41), and then fixedly connecting the pipe clamp (43) to the fixed connecting plate (42), and installing the test pipe (5) on the pipe clamp (43); S13, the stress corrosion testing machine connecting rod (32) is fixedly connected to the autoclave (1), and the position of the test pipe (5) is fixed by using the lower pipe clamp (33) and the upper pipe clamp (43); S14, the micro-wear connecting rod (22) is fixedly connected to the autoclave (1), and then the micro-vibration connecting plate (23), the micro-vibration connecting rod (24) and the micro-wear pressure head (25) are installed in sequence, and the load of the micro-vibration pressure head (25) is adjusted so that the test pipe (5) reaches a preset pressing force.

9. The method for using the pipe service behavior evaluation device according to claim 7, characterized in that: In step S3, the stress corrosion tester (31) applies stress corrosion loads to the test pipe (5) of the following types: constant load, slow strain rate tensile load and fatigue load.

10. The method for using the pipe service behavior evaluation device according to claim 7, characterized in that: In step S4, the vibration parameter information includes amplitude, frequency and waveform.

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