Rotary test platform and flap valve closing performance test device

Abstract

The present invention relates to a rotary experimental platform and a flap valve closing performance test device, comprising a platform, wherein the platform comprises a first base, a second base, a first rotary drive mechanism and a second rotary drive mechanism; the first rotary drive mechanism is connected to the first base, and is used to drive the first base and the second base to rotate in a first direction; the second base is rotationally connected to the first base, and the second rotary drive mechanism is connected to the second base, and is used to drive the second base to rotate relative to the first base in a second direction; the second direction is perpendicular to the first direction. The inclination of the platform in the present invention is adjustable, and the closing condition of the flap valve under different drilling directions can be tested; the second base can rotate relative to the first base, so that the valve disc and valve seat can rotate as a whole around the valve seat axis, and under the joint action of the first base and the second base, the valve disc can be tested at different inclination angles and different placement positions.

Description

Technical Field

[0001] The invention relates to the technical field of pressure-maintaining coring experimental devices, and in particular to a rotary experimental platform and a flap valve closing performance testing device. Background Art

[0002] The physical, mechanical, chemical and biological properties of deep rocks are closely related to their in situ environmental conditions. The loss of in situ environment during the coring process will lead to irreversible distortion of the physical, chemical and mechanical properties of the core. The core and key to the research is how to obtain in situ cores under deep environmental conditions and conduct real-time loading tests and analysis under in situ fidelity conditions.

[0003] The current in-situ fidelity coring device uses a drill to drill the core and then stores the core in a fidelity chamber. The sample is then pressure-sealed using a fidelity chamber pressure control device.

[0004] The pressure control device of the fidelity chamber includes a pressure maintaining valve, which includes a ball valve, a flap valve, etc. When the core barrel is lifted to a certain height, the flap valve can be automatically closed. At present, the closing of the flap valve mainly relies on elastic triggering. This elastic-triggered flap valve can only be used when drilling vertically, and there are problems such as sealing failure due to the side flipping of the valve disc.

[0005] Patent document CN110847856A discloses a magnetically triggered pressure-maintaining coring flap valve structure, in which a magnetic part is provided on the valve seat and a magnetic material is provided on the valve flap. Theoretically, the valve flap can be magnetically attracted by the valve seat without external force, and then automatically closed. However, this magnetic flap valve is still only in the theoretical stage, and its pressure-maintaining performance needs to be verified and improved.

[0006] In actual exploration work, there will be vertical drilling, horizontal drilling, inclined drilling, etc. Testing the closing condition of the magnetic flap valve at a specific angle is essential for verifying and improving the pressure-maintaining performance of the fidelity chamber. However, the existing experimental platform can only conduct experiments in a fixed position. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides a rotary experimental platform and a flap valve closing performance testing device.

[0008] The present invention is achieved through the following technical solutions:

[0009] A rotary experimental platform, comprising a platform, the platform comprising a first base, a second base, a first rotary drive mechanism and a second rotary drive mechanism;

[0010] The first rotation driving mechanism is connected to the first base, and is used to drive the first base and the second base to rotate in a first direction;

[0011] The second base is rotatably connected to the first base, and the second rotation drive mechanism is connected to the second base to drive the second base to rotate relative to the first base in a second direction;

[0012] The second direction is perpendicular to the first direction.

[0013] Furthermore, rotating shafts are connected to both sides of the first base, and the rotating shafts are supported on the supporting seat through bearings and bearing seats; the first rotating drive mechanism is connected to one of the rotating shafts.

[0014] Preferably, the first rotation drive mechanism is a manual mechanism.

[0015] Further, the first rotation drive mechanism includes a first hand wheel and a first transmission mechanism, and the first transmission mechanism converts the rotational motion of the first hand wheel into the rotational motion of the rotation shaft and the first base;

[0016] The rotation axis is perpendicular to the axis of the first handwheel.

[0017] Preferably, the second rotation drive mechanism comprises a motor.

[0018] Furthermore, a circular hole adapted to the valve seat is provided on the second base, and the axis of the circular hole is coaxial with the rotation center of the second base.

[0019] Furthermore, the rotary experimental platform also includes a box with an observation window, and the platform is placed in the box.

[0020] The flap valve closing performance testing device comprises a valve seat fixing mechanism for fixing the valve seat, a core barrel driving mechanism for driving the core barrel to rise and fall, and the rotary experimental platform, wherein the valve seat fixing mechanism and the core barrel driving mechanism are mounted on the second base.

[0021] Furthermore, the flap valve closing performance test device also includes a valve seat fixing mechanism for fixing the valve seat, and a core barrel driving mechanism for driving the core barrel to rise and fall;

[0022] The valve seat fixing mechanism and the core barrel driving mechanism are installed on the second base.

[0023] Preferably, the valve seat fixing mechanism is a manual mechanism, and the core barrel driving mechanism is an automatic mechanism.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The inclination of the platform in the present invention is adjustable, and the closing condition of the flap valve under different drilling directions can be tested; the second base can rotate relative to the first base, so that the valve disc and valve seat can rotate as a whole around the valve seat axis. Under the joint action of the first base and the second base, the valve disc can be tested at different inclination angles and different placement positions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention.

[0027] Figure 1 It is a three-dimensional picture of the rotating experimental platform;

[0028] Figure 2 is a three-dimensional diagram of the flap valve closing performance testing device in Example 1;

[0029] Figure 3 is a three-dimensional diagram of the experimental table inside the box in Example 1;

[0030] Figure 4 It is a three-dimensional diagram of the valve seat fixing mechanism and the core barrel driving mechanism when they are installed on the platform;

[0031] Figure 5 is a schematic diagram of using the present invention to test a flap valve;

[0032] Figure 6 It is a structural schematic diagram of the movable clamp and its operating mechanism;

[0033] Figure 7 It is a structural schematic diagram of a magnet linear displacement adjustment mechanism;

[0034] Figure 8 It is a structural diagram of a flap valve. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0038] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0039] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "forward", "reverse", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed when in use, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply 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 on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0040] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] like Figure 1 As shown, the rotary experimental platform disclosed in the present invention comprises a platform 4 , which specifically comprises a first base 41 , a second base 42 , a first rotary drive mechanism 47 and a second rotary drive mechanism 43 .

[0042] Rotating shafts 44 are fixedly connected to both sides of the first base 41, and the rotating shafts 44 are supported on the supporting base 45 through bearings and bearing seats 46. A first rotating driving mechanism 47 is connected to one of the rotating shafts 44, and is used to drive the first base 41 to rotate in a first direction.

[0043] The second base 42 is rotatably connected to the first base 41, the second rotation drive mechanism 43 is mounted on the first base 41, and the output end of the second rotation drive mechanism 43 is connected to the second base 42 to drive the second base 42 to rotate relative to the first base 41 in a second direction. The second direction is perpendicular to the first direction.

[0044] The first rotation drive mechanism 47 and the second rotation drive mechanism 43 can be manual mechanisms or electric mechanisms. In this embodiment, the first rotation drive mechanism 47 is a manual mechanism, and the second rotation drive mechanism 43 is an electric mechanism.

[0045] The first rotary drive mechanism 47 includes a first hand wheel 471 and a first transmission mechanism. The first transmission mechanism converts the rotary motion of the first hand wheel 471 into the rotary motion of the rotary shaft 44 and the first base 41. In this embodiment, the rotary shaft 44 is perpendicular to the axis of the first hand wheel 471, so the first transmission mechanism is a vertical transmission mechanism, and a bevel gear vertical transmission mechanism can be selected. The first hand wheel 471 is the driving wheel, and the first transmission mechanism is the driven wheel. By designing a suitable transmission ratio, the platform 4, the valve seat and the valve disc can be rotated around the rotary shaft 44, thereby simulating vertical drilling, horizontal drilling, inclined drilling, etc.

[0046] The second rotation driving mechanism 43 includes a motor and a gear transmission mechanism, and the gear transmission mechanism converts the rotational motion of the motor into the rotational motion of the second base 42 .

[0047] The second base 42 has a circular hole 421 adapted to the valve seat, and the axis of the circular hole 421 is coaxial with the rotation center of the second base 42. When the flap valve is installed on the second base 42, the second rotary drive mechanism 43 operates to drive the second base 42, the valve seat and the valve disc to rotate synchronously around the axis of the valve seat.

[0048] The inclination of the platform in the present invention is adjustable, and the closing condition of the flap valve under different drilling directions can be tested; the second base can rotate relative to the first base, so that the valve disc and valve seat can rotate as a whole around the valve seat axis. Under the joint action of the first base and the second base, the valve disc can be tested at different inclination angles and different placement positions.

[0049] Based on the above-mentioned rotating experimental platform, the present invention discloses two embodiments.

[0050] Embodiment 1

[0051] like Figure 2 , Figure 3 As shown, this embodiment discloses a flap valve closing performance testing device, including a valve seat fixing mechanism 6 for fixing the valve seat, a core barrel driving mechanism 5 for driving the core barrel to rise and fall, and the above-mentioned rotary experimental platform.

[0052] The platform 4 is placed in the box 100, and the box 100 has an observation window. Placing the platform 4 in the box 100 has three functions: first, it realizes the protection function. When the valve disc is closed, air pressure is used to determine its preload. If the box is not used, there will be certain experimental dangers due to excessive air pressure; second, it realizes the modular hiding of the control mechanism, and various pneumatic and electric devices are placed in the box 100 and packaged to achieve a neat and functional modular effect; third, the test bench not only has an experimental function, but also has a certain valve seat closing action display function. When the experiment is not needed, the valve disc closing state can be dynamically displayed. Under this function, the platform is placed in the box 100 to prevent external interference during the dynamic display process, and a high-speed image tracking system can be integrated in the box 100 to realize the dynamic image collection during the valve disc closing process.

[0053] The valve seat fixing mechanism 6 and the core barrel driving mechanism 5 are mounted on the second base 42 .

[0054] like Figure 6 As shown, the valve seat fixing mechanism 6 includes a pair of clamps and an operating mechanism, one of the pair of clamps is a fixed clamp 62, and the other is a movable clamp 61. The operating mechanism is connected to the movable clamp 61 for operating the movable clamp 61.

[0055] A linear guide 66 is provided on the upper surface of the second base 42, and the movable clamp 61 is slidably connected to the linear guide 66. The operating mechanism includes a handle 65, an arm 1 63, an arm 2 67, and an arm 3 68. One end of the arm 1 63 is connected to the movable clamp 61, the other end of the arm 1 63 is rotatably connected to one end of the arm 2 67, the other end of the arm 2 67 is rotatably connected to one end of the arm 3 68, the other end of the arm 3 68 is rotatably connected to the mounting seat 64, the mounting seat 64 is fixedly connected to the second base 42, and one end of the handle 65 is fixedly connected to the arm 3 68.

[0056] By rotating the handle 65 forward or backward, the arm three 68 can be driven to rotate around the mounting seat 64, thereby pulling or pushing the arm one 63 and the movable clamp 61 to move linearly, thereby adjusting the distance between the movable clamp 61 and the fixed clamp 62, and then clamping or loosening the valve seat.

[0057] The core barrel driving mechanism 5 is used to lift the core barrel. The core barrel driving mechanism 5 includes a core barrel clamp 54 for clamping the core barrel and a linear driving mechanism for driving the core barrel clamp 54 to move linearly. The linear driving mechanism can be a hydraulic cylinder, a pneumatic cylinder, a linear motor, etc.

[0058] In this embodiment, the linear drive mechanism is a linear motor, which specifically includes a motor 51 , a linear guide rail 52 , a slider 53 , a ball screw, etc. This is conventional technology in the art and will not be described in detail.

[0059] like Figure 4 , Figure 8 As shown, the flap valve comprises a valve seat 1 and a valve flap 2 , wherein the valve flap 2 is connected to one side of the top end of the valve seat 1 .

[0060] The valve disc 2 is provided with a second magnetic member 9, and the valve seat 1 is provided with a third magnetic member 10 for attracting the second magnetic member 9. In another embodiment, the valve seat 1 may not be provided with the third magnetic member 10. In order to facilitate the testing of the sealing pressure of the flap valve, a sealing plate 11 is connected to the bottom end of the valve seat 1, and an air injection hole 12 is provided on the sealing plate 11; when the valve disc is closed, air pressure can be injected into the valve seat 1 through the air injection hole 12, and the maximum sealing pressure can be tested by monitoring the change of the internal pressure.

[0061] In order to provide an initial closing force for the valve flap 2, the second base 42 is also equipped with a first magnetic member 8 with adjustable position and a magnet linear displacement adjustment mechanism 7 for linearly adjusting the position of the first magnetic member 8. By adjusting the position of the first magnetic member 8, the repulsive force of the first magnetic member 8 on the second magnetic member 9 is adjusted. The magnetic member can be a magnet, such as a permanent magnet. The second magnetic member 9 can be embedded in the valve flap 2.

[0062] As a better choice: the valve flap 2 is made of a paramagnetic material with high magnetic permeability and high compressive strength. The reason is: when the valve flap 2 is made of paramagnetic material, the permanent magnet on the valve flap 2 will magnetize the valve flap 2. After the valve flap 2 is closed, the magnetic potential of the permanent magnet inside the valve seat 1 will couple with the magnetic potential of the valve flap 2. According to the principle of minimum potential energy, it will have a greater attractive force, thereby overcoming the gravitational potential and achieving a continuous closing effect. In the embodiment, iron is selected to make the valve flap 2, and stainless steel is selected for the valve seat 1. The reason for selecting stainless steel to make the valve seat 1 is that stainless steel is a low magnetic permeability material, and the magnetic field inside it will not generate magnetic potential for it, which will not affect the closing trajectory of the valve flap 2.

[0063] like Figure 4 , Figure 5 As shown, the magnet linear displacement adjustment mechanism 7 is installed on the surface of the second base 42. The magnet linear displacement adjustment mechanism 7 can be a manual mechanism, or an automatic mechanism such as an electric, pneumatic, or hydraulic mechanism.

[0064] like Figure 7 As shown, in this embodiment, the magnet linear displacement adjustment mechanism 7 is a manual mechanism. The magnet linear displacement adjustment mechanism 7 includes a second hand wheel 71 and a second transmission mechanism, and the second transmission mechanism converts the rotational motion of the second hand wheel 71 into the linear motion of the first magnetic member 8. In this embodiment, the axis of the second hand wheel 71 is perpendicular to the displacement direction of the first magnetic member 8, so the second transmission mechanism includes a worm gear transmission mechanism and a lead screw nut transmission mechanism.

[0065] The nut 75 of the screw nut transmission mechanism is slidably connected to the second base 42, the magnet mounting seat 77 is connected to the nut 75 through the guide rod 76, the first magnetic member 8 is mounted on the magnet mounting seat 77, a pressure sensor 78 is provided between the first magnetic member 8 and the magnet mounting seat 77, and the magnet mounting seat 77 is slidably connected to the second base 42. Its working principle is as follows:

[0066] (1) Manually rotate the second hand wheel 71 to drive the worm 72 to drive the turbine 73 to rotate vertically;

[0067] (2) The turbine 73 is on the screw 74, and the rotating screw 74 drives the nut 75 to move linearly;

[0068] (3), the nut 75 transmits the motion to the magnet mounting seat 77, the pressure sensor 78 and the first magnetic member 8 through the guide rod 76;

[0069] (4) When the first magnetic member 8 encounters the second magnetic member 9 on the valve disc, since the second magnetic member 9 and the first magnetic member 8 have the same poles facing each other, when the magnets with the same poles produce repulsion, pressure will be generated on the pressure sensor 78, and the magnitude of the repulsive force can be measured by the pressure sensor 78.

[0070] By measuring the repulsive force, the initial acceleration can be determined, thereby establishing a dynamic model of valve flap closure and studying the instantaneous motion state of the valve flap during rotation and closure. Moreover, the measured repulsive force can be compared with the elastic force generated by the existing spring trigger model, and the size of the existing magnet can be optimized based on the dynamic model.

[0071] In order to test the sealing pressure, the flap valve closing performance test device also includes an air injection system, which is used to inject gas into the closed flap valve. The air injection system includes an air pressure pump, an air injection pipe and a pressure valve. The air injection pipe is used to be sealed and connected to the air injection hole 12 at the bottom of the valve seat. The pressure valve value is converted into real-time data on the display screen through a computer.

[0072] The box 100 is provided with a control system, which includes a controller and a human-machine interaction module 101. The second rotary drive mechanism 43, the core barrel drive mechanism 5 and the gas injection system are all connected to the control system.

[0073] The control system can reduce the number of manual operations, adopt human-computer interaction, realize artificial intelligence operation, which is convenient and fast, and reduces the experimental accuracy problems and safety risks caused by manual operation during the experiment. The functions of the control system mainly include: controlling the rapid lifting of the core barrel, and realizing the monitoring of the lifting speed; controlling the first base 41 and the valve seat disc to rotate freely 360° around the valve seat axis, monitoring the closing of the valve disc at different positions, and realizing the control and monitoring of the rotation angle; after the flap valve is closed, the preload force test can be realized, and the air pressure can be controlled by the human-computer interaction module to realize real-time monitoring.

[0074] The lifting and lowering of the core barrel is controlled by the core barrel driving mechanism 5. By controlling the speed of the motor 51, the lifting and lowering speed of the core barrel can be controlled; naturally, the lifting and lowering speed of the core barrel can be monitored by the rotation speed of the motor.

[0075] By adjusting the lifting speed of the core barrel, the extraction speed of the core barrel in the field can be simulated as realistically as possible; in addition, the existence of an optimal lifting speed can be determined through experiments.

[0076] The method of using the present invention:

[0077] 1. Initial state: Figure 4 , 5 As shown, the valve seat 1 of the flap valve is clamped by the fixed clamp 62 and the movable clamp 61, and the core barrel 3 is clamped by the core barrel clamp 54; in the initial state, the core barrel 3 is located in the valve seat 1, and the valve flap 2 of the flap valve is in the open state. At this time, the first magnetic component 8 will give the valve flap 2 an initial power, and the initial power can be measured by the corresponding pressure sensor 78.

[0078] 2. Initial experiment: the valve seat 1 is axially perpendicular to the horizontal plane, the core barrel driving mechanism 5 is running, and the core barrel 3 is lifted. When the core barrel 3 is moved out of the valve seat 1 and passes over the valve flap 2, the valve flap 2 performs variable acceleration motion under the repulsive force of the first magnetic member 8 to achieve rotational closure, which simulates the normal vertical coring state.

[0079] 3. Re-adjust to the initial state, turn the first hand wheel 471 to make a certain angle between the axis of the valve seat 1 and the horizontal plane, and use the control system to rotate the second base 42 to a certain angle. At this time, the core barrel driving mechanism 5 runs to lift the core barrel 3. When the core barrel 3 is moved out of the valve seat 1, if the valve disc 2 can realize the rotational closing power process at different angles, it means that the rotational closing experiment is successful.

[0080] When the valve flap 2 is closed, the third magnetic part 10 on the valve seat 1 will generate a pre-tightening force on the valve flap 2, so that the valve flap 2 produces a tight closing effect. At this time, gas is filled into the valve seat 1 through the human-computer interaction module 101, and the air pressure is monitored by a pressure gauge. At this time, the real-time status of the air pressure will be displayed on the display screen of the control system. When the air pressure reaches the maximum value, it will be depressurized, and the control system will automatically record and display the peak value of the air pressure and the process change law.

[0081] The peak value of the air pressure inside the valve seat 1 is the preload force generated by the third magnetic member 10 on the valve seat 1 on the valve disc 2, which is called the initial preload force. When the initial preload force is large, the valve disc will have a certain pressure-maintaining ability, thereby achieving a pressure-maintaining effect after closing.

[0082] Embodiment 2

[0083] In this embodiment, the first base 41 and the second base 42 are disc-shaped. The first base 41 and the second base 42 are arranged in parallel. Two rotating shafts 44 are radially arranged on opposite sides of the first base 41.

[0084] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. The flap valve closing performance test device is characterized by: It includes a valve seat fixing mechanism for fixing the valve seat, a core barrel driving mechanism for driving the core barrel to rise and fall, a rotary experimental platform and a flap valve; The rotary experimental platform comprises a platform, wherein the platform comprises a first base, a second base, a first rotation drive mechanism, and a second rotation drive mechanism; The first rotation driving mechanism is connected to the first base, and is used to drive the first base and the second base to rotate in a first direction; The second base is rotatably connected to the first base, and the second rotation drive mechanism is connected to the second base to drive the second base to rotate relative to the first base in a second direction; The second direction of rotation is perpendicular to the first direction of rotation; The valve seat fixing mechanism and the core barrel driving mechanism are installed on the second base. The flap valve includes a valve seat and a valve disc. The valve disc is connected to one side of the top of the valve seat. The bottom of the valve seat is connected to a sealing plate, and the sealing plate has an air injection hole. When the valve disc is closed, the third magnetic part on the valve seat will generate a pre-tightening force on the valve disc. The initial pre-tightening force of the valve disc can be tested by monitoring the internal pressure of the valve seat. When the valve disc is closed, air pressure can be injected into the valve seat through the air injection hole. The maximum sealing pressure can be tested by monitoring the changes in the internal pressure.

2. The flap valve closing performance testing device according to claim 1, characterized in that: The two sides of the first base are connected with rotating shafts, and the rotating shafts are supported on the supporting seat through bearings and bearing seats; the first rotating driving mechanism is connected to one of the rotating shafts.

3. The flap valve closing performance testing device according to claim 2, characterized in that: The first rotation driving mechanism is a manual mechanism.

4. The flap valve closing performance testing device according to claim 3, characterized in that: The first rotary drive mechanism comprises a first hand wheel and a first transmission mechanism, wherein the first transmission mechanism converts the rotary motion of the first hand wheel into the rotary motion of the rotary shaft and the first base; The rotation axis is perpendicular to the axis of the first handwheel.

5. The flap valve closing performance testing device according to claim 1, 3 or 4, characterized in that: The second rotation drive mechanism includes a motor.

6. The flap valve closing performance testing device according to claim 1, characterized in that: The second base has a circular hole matched with the valve seat, and the axis of the circular hole is coaxial with the rotation center of the second base.

7. The flap valve closing performance testing device according to claim 1, characterized in that: It also includes a box body with an observation window, and the platform is placed in the box body.

8. The flap valve closing performance testing device according to any one of claims 1-4, 6, and 7, characterized in that: The valve seat fixing mechanism is a manual mechanism, and the core barrel driving mechanism is an automatic mechanism.

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