A nuclear power plant penetrator pipe outer wall polishing device and system

Abstract

This invention discloses a grinding device for the outer wall of a through-hole pipe in a nuclear power plant. It includes an mounting ring, an axial motion mechanism, a circumferential motion mechanism, and a grinding mechanism. The grinding mechanism includes a grinding wheel and a grinding wheel drive assembly for driving the grinding wheel closer to or away from the axis of the mounting ring. The rotation axis of the grinding wheel is perpendicular to or inclined to the axis of the mounting ring. The device can be fixed to the outer wall surface of the pipe being inspected and can achieve axial and circumferential crawling motion of the pipe. After installation, the device has a small radial space dimension in the pipe, allowing it to enter the narrow space between the cover and the outer wall of the pipe being inspected. Given the long longitudinal dimension of the cover, the device needs to be able to provide real-time feedback on its spatial position. The grinding device can achieve good coupling between the grinding wheel and the grinding surface, and can flexibly control the coupling force of the grinding wheel when encountering unevenness on the pipe surface, thus achieving constant force grinding.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power testing equipment, and specifically relates to a grinding device and system for the outer wall of a through-hole pipe in a nuclear power plant. Background Technology

[0002] For pressurized water reactor (PWR) nuclear power plants, the heat generated by the nuclear fuel reaction within the nuclear island is transferred to the secondary side via a steam generator to produce saturated steam. This steam is then transported through the main steam pipe (VVP) to the turbine building in the conventional island, driving the turbine to generate electricity. After generating power, the steam is pumped back to the steam generator via the main feedwater pipe (ARE), completing the energy conversion in the secondary loop. Therefore, the ARE and VVP pipes connect the nuclear island and the conventional island, running through the nuclear island walls; the sections that pass through are called penetrations. At both ends of the penetration, the pipes are welded to the penetration. Due to the high pressure inside the pipes, ultrasonic testing of the weld seams in the penetrations is required according to the power plant's operational requirements. This is an essential monitoring method during the power plant's operation. Before conducting automatic ultrasonic testing of the ARE / VVP, it is necessary to ensure that the surface of the area to be inspected has sufficient flatness and roughness. Excessive roughness in the inspected area can lead to a decrease in ultrasonic signal quality, loss of defect signals, and consequently affect the evaluation of weld quality. However, the pipe material in this part is P355NH ferritic steel. After a period of high temperature and high pressure operation, the outer surface of the pipe will develop surface rust, which cannot meet the requirements of ultrasonic testing. It is necessary to treat the surface rust of the pipe in advance. The through-piece pipe is installed inside the cover tube, and the inspection space of the weld to be inspected is limited. It is a closed annular area. The narrowest distance between the cover tube and the outer wall of the pipe to be inspected is 150mm, and the maximum depth is about 3m. Valves and pipes are also installed nearby. The space for surface rust grinding is small, manual grinding is difficult to perform, and the grinding quality is poor. Summary of the Invention

[0003] The purpose of this invention is to provide a grinding device for the outer wall of a nuclear power plant through-hole pipe, which can automatically grind any position along the outer wall of the through-hole pipe and, in the event of failure of the axial movement mechanism, utilize the grinding mechanism to achieve device recovery.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a grinding device for the outer wall of a through-hole pipe in a nuclear power plant, comprising...

[0005] The mounting ring can be fitted onto the through pipe, and the space enclosed by its inner circumference extending along its axis is the inner space.

[0006] An axial motion mechanism for driving the device to move along the axis of the mounting ring;

[0007] A circumferential motion mechanism for driving the device to rotate about the axis of the mounting ring;

[0008] A grinding mechanism, which is mounted on the mounting ring and used to grind the outer wall of the through-hole pipe;

[0009] The grinding mechanism includes a grinding wheel and a grinding wheel drive assembly for driving the grinding wheel closer to or away from the axis of the mounting ring. The rotation axis of the grinding wheel is perpendicular to or inclined to the axis of the mounting ring. When the mounting ring is installed on the through-hole pipe and the grinding wheel is close to the axis of the mounting ring and in contact with the outer wall of the through-hole pipe, the grinding wheel has a first working position and a second working position. When the grinding wheel is in the first working position, the grinding wheel is against the outer wall of the through-hole pipe, and the grinding wheel can grind the outer wall of the through-hole pipe. The friction between the wheel and the outer wall of the pipe is insufficient to move the device on the through pipe. When the grinding wheel is in the second working position, the grinding wheel is in close contact with the outer wall of the through pipe. The grinding wheel can grind the outer wall of the through pipe, and the friction between the grinding wheel and the outer wall of the pipe is sufficient to move the device on the through pipe. In addition to grinding the outer wall of the through pipe in the first working position, the grinding wheel can also increase the friction between the grinding wheel and the outer wall of the through pipe when the axial movement mechanism fails, so that the grinding mechanism can move the device out of the through pipe.

[0010] In another embodiment, the circumferential motion mechanism includes a circumferential driving wheel and a circumferential driven wheel mounted on the mounting ring and having at least a portion located in the inner space of the mounting ring, and a circumferential drive motor for driving the circumferential driving wheel to rotate, wherein the rotation axes of the circumferential driving wheel and the circumferential driven wheel are parallel to the axis of the mounting ring.

[0011] In another embodiment, the circumferential driving wheel includes a first circumferential driving wheel and a second circumferential driving wheel, with the first circumferential driving wheel and the second circumferential driving wheel located on the front end face and the rear end face of the mounting ring, respectively.

[0012] In another embodiment, the circumferential driven wheel includes a first circumferential driven wheel and a second circumferential driven wheel, the first circumferential driven wheel and the second circumferential driven wheel being located on the front end face and the rear end face of the mounting ring, respectively.

[0013] In another embodiment, both the first circumferential drive wheel and the second circumferential drive wheel are omnidirectional wheels, and the main rotation axes of the first circumferential drive wheel and the second circumferential drive wheel are parallel to the axis of the mounting ring.

[0014] In another embodiment, both the first circumferential driven wheel and the second circumferential driven wheel are omnidirectional wheels, and the main rotation axes of the first circumferential driven wheel and the second circumferential driven wheel are parallel to the axis of the mounting ring.

[0015] In another embodiment, the axial motion mechanism includes an axial drive wheel rotatably connected within the mounting ring and an axial drive motor for driving the axial drive wheel to rotate. The axial drive wheel has at least a portion located in the inner space of the mounting ring, and the axis of rotation of the axial drive wheel is perpendicular to the axis of the mounting ring.

[0016] In another embodiment, the axial drive wheel is an omnidirectional wheel, and the main shaft of the axial drive wheel is perpendicular to the axis of the mounting ring.

[0017] In another embodiment, the grinding wheel drive assembly includes a rotary cylinder mounted on a mounting ring, a pneumatic mill mounted on the rotary cylinder's rotating shaft, and the grinding wheel mounted on the pneumatic mill's output shaft. When the rotary cylinder rotates, it drives the pneumatic mill to swing toward or away from the outer wall of the through-hole pipe.

[0018] In another embodiment, the projections of the circumferential driving wheel, the circumferential driven wheel, and the axial driving wheel on the end face of the mounting ring are evenly distributed on the end face of the mounting ring.

[0019] In another embodiment, the device further includes a video surveillance component.

[0020] In another embodiment, the video surveillance component includes a camera and a lighting fixture.

[0021] In another embodiment, the device further includes a rangefinder for detecting the distance between the device and the through-hole cover tube.

[0022] In another embodiment, the device further includes a level for detecting the angle between the device and the horizontal plane.

[0023] In another embodiment, the mounting ring includes a first semi-circular half-ring and a second semi-ring, which are generally semi-circular. One end of the first semi-ring and the second semi-ring are rotatably connected, and the other end is connected by a snap fastener.

[0024] In another embodiment, the buckle includes a locking pin rotatably connected to the first half-ring, a locking nut threadedly connected to the locking pin, and a spring sleeved on the locking pin and limited by the locking nut on the locking pin.

[0025] The present invention also provides a grinding system for the outer wall of a through-hole pipe in a nuclear power plant, which includes an electrical control unit and a grinding device, wherein the grinding device is the aforementioned grinding device.

[0026] In another embodiment, the electronic control unit controls the pressure F applied by the grinding drive assembly to the grinding wheel in the radial direction of the pipe based on the position of the grinding wheel in the circumferential direction of the pipe. 压 This causes the coupling force F between the grinding wheel and the pipe to be so strong. 耦 Always remain constant.

[0027] In another embodiment, the system includes a pressure F mounted on the grinding wheel drive assembly for detecting and feeding back the pressure F applied by the grinding drive assembly to the grinding wheel in the radial direction of the pipe. 压 The pressure sensor, the electronic control unit controls the grinding drive assembly to apply the radial pressure F to the grinding wheel in the pipeline based on the position of the grinding wheel in the circumferential direction of the pipeline. 压 And according to the formula: F 耦 =F 压 +G 磨 ×sinα×cosβ, i.e., F 压 =F 耦 -G 磨 ×sinα×cosβ, adjusting pressure F 压 The coupling force F between the grinding wheel and the pipe 耦 Always remain constant, where G 磨 The value is the weight of the grinding wheel itself. α is the angle between the perpendicular line from the center of gravity of the grinding wheel to the axis of the pipe and the horizontal plane, provided by a horizontal angle meter. β is the angle between the pipe and the horizontal plane, which is 0 in this case.

[0028] The beneficial effects of this invention are as follows: the equipment can be fixed on the outer wall surface of the inspected pipe, enabling axial and circumferential crawling motion of the pipe; after installation, the radial space dimension of the pipe is small, allowing the equipment to enter the narrow space between the cover and the outer wall of the inspected pipe; the cover has a long longitudinal dimension, requiring the equipment to provide real-time feedback on its spatial position; the grinding device of the equipment can achieve good coupling between the grinding wheel and the grinding surface, and can flexibly control the coupling force of the grinding wheel when encountering unevenness on the pipe surface, thus achieving constant force grinding; the equipment can display real-time observation and inspection of the pipe grinding effect or post-grinding observation and inspection, i.e., the equipment is equipped with a video monitoring module. Attached Figure Description

[0029] Figure 1 This is a schematic diagram illustrating the principle of the present invention;

[0030] Figure 2 This is a structural diagram of an omnidirectional wheel;

[0031] Figure 3 This is a schematic diagram of the invention installed on a pipeline;

[0032] Figure 4 This is a schematic diagram showing the positional relationship between the grinding wheel and the pipe. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings:

[0034] like Figure 4As shown, the nuclear power plant through-pipe external wall grinding system includes an electrical control unit, a grinding device, and a pressure sensor. The pressure sensor is mounted on the grinding wheel drive assembly to detect and provide feedback on the radial pressure F applied to the grinding wheel by the grinding drive assembly. 压 The electrical control unit controls the pressure F applied to the grinding wheel by the grinding drive assembly in the radial direction of the pipe based on the position of the grinding wheel in the circumferential direction of the pipe. 压 And according to the formula: F 耦 =F 压 +G 磨 ×sinα×cosβ, i.e., F 压 =F 耦 -G 磨 ×sinα×cosβ, adjusting pressure F 压 The coupling force F between the grinding wheel and the pipe 耦 Always remain constant, where G 磨 The value is the weight of the grinding wheel itself. α is the angle between the perpendicular line c of the grinding wheel's center of gravity and the pipe axis G and the horizontal plane Z, provided by a horizontal angle meter. β is the angle between the pipe axis b and the horizontal plane Z, which is 0 in this case.

[0035] like Figure 1 As shown, the grinding device 0 for the outer wall of the through-hole pipe in a nuclear power plant includes a mounting ring 1, an axial motion mechanism, a circumferential motion mechanism, a grinding mechanism 4, a video monitoring component 5, a rangefinder 6 for detecting the distance between the device and the through-hole cover B, and a level 7 for detecting the angle between the device and the horizontal plane.

[0036] The installation ring 1 can be fitted onto the through pipe A, and the space covered by its inner circumference extending along its axis is the inner space.

[0037] The grinding mechanism 4 is mounted on the mounting ring 1 and is used to grind the outer wall of the through pipe A. The grinding mechanism 4 includes a grinding wheel 41 and a grinding wheel drive assembly for driving the grinding wheel 41 to approach or move away from the axis of the mounting ring 1. The grinding wheel drive assembly includes a rotary cylinder 42 mounted on the mounting ring 1 and a pneumatic grinder 44 mounted on the rotating shaft of the rotary cylinder 42. The grinding wheel 41 is mounted on the output shaft 43 of the pneumatic grinder. When the rotary cylinder 42 rotates, the rotary cylinder 42 drives the pneumatic grinder to swing toward or away from the outer wall of the through pipe A. The rotation axis of the grinding wheel 41 is perpendicular or inclined to the axis of the mounting ring 1. However, when it comes into contact with the pipe A, it always generates a frictional force parallel to the axis of the mounting ring 1. When the mounting ring 1 is installed on the through pipe A and the grinding wheel 41 is close to the axis of the mounting ring 1 and in contact with the outer wall of the through pipe A, the grinding wheel 41 has a first working position and a second working position. When the grinding wheel 41 is in the first working position, the grinding wheel 41 is against the outer wall of the through pipe A, and the grinding wheel 41 can grind the outer wall of the through pipe A. The frictional force between the grinding wheel 41 and the outer wall of the pipe A is... The friction between the grinding wheel 41 and the outer wall of the through pipe A is insufficient to move the device on the through pipe A. When the grinding wheel 41 is in the second working position, the grinding wheel 41 is in close contact with the outer wall of the through pipe A. The grinding wheel 41 can grind the outer wall of the through pipe A, and the friction between the grinding wheel 41 and the outer wall of the pipe A is sufficient to move the device on the through pipe A. In addition to grinding the outer wall of the through pipe A in the first working position, the grinding wheel 41 can also, when the axial motion mechanism fails, increase the friction between the grinding wheel 41 and the outer wall of the through pipe A, so that the grinding mechanism 4 can move the device out of the through pipe A.

[0038] A circumferential motion mechanism is used to drive the device to rotate around the axis of the mounting ring 1. It includes a circumferential driving wheel and a circumferential driven wheel mounted on the mounting ring 1, each having at least a portion located within the inner space of the mounting ring 1; and a circumferential drive motor 33 for driving the circumferential driving wheel to rotate. The rotation axes of the circumferential driving wheel and the circumferential driven wheel are parallel to the axis of the mounting ring 1. The circumferential driving wheel includes a first circumferential driving wheel 31a and a second circumferential driving wheel 31b, located on the front and rear faces of the mounting ring 1, respectively. The circumferential driven wheel includes a first circumferential driven wheel 32a and a second circumferential driven wheel 32b, located on the front and rear faces of the mounting ring 1, respectively. Both the first circumferential driving wheel 31a and the second circumferential driving wheel 31b are omnidirectional wheels, and their main rotation axes are parallel to the axis of the mounting ring 1. The first circumferential driven wheel 32a and the second circumferential driven wheel 32b are both omnidirectional wheels. The omnidirectional wheel includes a main shaft 301, a main wheel body 302, and an idler wheel 303 that is rotatably connected to the main wheel body 302 and whose axis of rotation is perpendicular to the main shaft 301. The axis of rotation of the main shaft 301 is the main axis of rotation, and the main axes of rotation of the first circumferential driven wheel 32a and the second circumferential driven wheel 32b are parallel to the axis of the mounting ring 1.

[0039] The axial motion mechanism is used to drive the device to move along the axis of the mounting ring 1. It includes an axial drive wheel 21 rotatably connected within the mounting ring 1 and an axial drive motor 22 for driving the axial drive wheel 21 to rotate. The axial drive wheel has at least a portion located in the inner space of the mounting ring 1, and the axis of rotation of the axial drive wheel is perpendicular to the axis of the mounting ring 1. The axial drive wheel is an omnidirectional wheel, and the main shaft 301 of the axial drive wheel is perpendicular to the axis of the mounting ring 1.

[0040] The projections of the circumferential driving wheel, the circumferential driven wheel, and the axial driving wheel on the end face of the mounting ring 1 are evenly distributed on the end face of the mounting ring 1.

[0041] The video surveillance component 5 includes a camera 51 and a lighting lamp 52. For ease of installation, the mounting ring 1 includes a first semi-circular ring 11 and a second semi-circular ring 12. One end of the first and second semi-circular rings is rotatably connected, and the other end is connected by a snap-fit ​​13. The snap-fit ​​includes a locking pin 131 rotatably connected to the first semi-circular ring, a locking nut 132 threadedly connected to the locking pin, and a spring 133 sleeved on the locking pin and limited by the locking nut on the locking pin.

[0042] The installation sequence of this invention is as follows:

[0043] 1. Connect the pipeline between the control module and the automated motion grinding equipment, and place the rotating grinding wheel away from the pipeline;

[0044] 2. Unfasten the mounting ring, open it to a certain angle so that the equipment can pass over the grinding pipe, close the mounting ring, and adjust the floating locking nut so that the circumferential drive wheel, circumferential driven wheel, and axial drive wheel are in contact with the grinding pipe;

[0045] 3. The remote control terminal controls the circumferential and axial movements of the grinding device, tests the axial and circumferential positioning functions, ensures that there are no obstructions between the rangefinder and the through-piece support, and confirms that the movement and positioning of the equipment meet the usage requirements. The equipment is then reset to the starting position.

[0046] 4. Test the condition of the pneumatic mill to ensure that the grinding wheel is properly installed and that the lighting and video functions of the video monitoring components are in good working order;

[0047] 5. Complete the overall installation and testing of the equipment.

[0048] Polishing work:

[0049] 1. The automated grinding equipment can be a movable device or a fixed positioning device, controlling the equipment to reach the designated position;

[0050] 2. Set the automatic grinding plan and grinding pressure. The grinder starts rotating after air is supplied, initiating the grinding operation. The rotating pneumatic motor begins its downward pressing action, and the entire equipment begins grinding according to the set grinding plan. Generally, the equipment performs a grid motion, with both grinding wheels grinding simultaneously to cover the entire grinding surface. If only one grinding wheel remains, it can also perform a full circumference grinding operation on the pipe.

[0051] 3. The video monitoring component next to the grinding wheel can monitor the grinding operation status;

[0052] 4. After grinding is completed, control the equipment to move to a suitable position and use the video monitoring component to re-inspect the ground surface to ensure that the grinding operation meets the requirements;

[0053] 5. For the non-compliant sanding areas, set up a new sanding plan and carry out the sanding operation until all sanding work is completed.

[0054] 6. The pneumatic grinder stops rotating and is lifted, the grinding equipment is retracted to the outside of the through-hole sleeve, and the equipment is removed;

[0055] 7. Blow away debris from the polishing area; polishing operation is complete.

[0056] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A grinding system for the outer wall of a nuclear power plant through-hole pipe, comprising an electrical control unit and a grinding device for the outer wall of a nuclear power plant through-hole pipe, characterized in that: A grinding device for the outer wall of through-hole pipes in nuclear power plants, comprising: The mounting ring can be fitted onto the through pipe, and the space enclosed by its inner circumference extending along its axis is the inner space. An axial motion mechanism for driving the device to move along the axis of the mounting ring; A circumferential motion mechanism for driving the device to rotate about the axis of the mounting ring; A grinding mechanism, which is mounted on the mounting ring and used to grind the outer wall of the through-hole pipe; The grinding mechanism includes a grinding wheel and a grinding wheel drive assembly for driving the grinding wheel closer to or away from the axis of the mounting ring. The rotation axis of the grinding wheel is perpendicular to or inclined to the axis of the mounting ring. When the mounting ring is installed on the through-hole pipe and the grinding wheel is close to the axis of the mounting ring and in contact with the outer wall of the through-hole pipe, the grinding wheel has a first working position and a second working position. When the grinding wheel is in the first working position, it rests against the outer wall of the through-hole pipe, and the grinding wheel can grind the outer wall of the through-hole pipe. The friction between the grinding wheel and the outer wall of the pipe is insufficient to move the device on the through-pipe. When the grinding wheel is in the second working position, it is in close contact with the outer wall of the through-pipe. The grinding wheel can grind the outer wall of the through-pipe, and the friction between the grinding wheel and the outer wall of the pipe is sufficient to move the device on the through-pipe. The circumferential motion mechanism includes a circumferential driving wheel and a circumferential driven wheel mounted on the mounting ring and having at least a portion located in the inner space of the mounting ring, and a circumferential drive motor for driving the circumferential driving wheel to rotate. The driven wheel's rotation axis is parallel to the axis of the mounting ring; the circumferential driving wheel includes a first circumferential driving wheel and a second circumferential driving wheel, the first circumferential driving wheel and the second circumferential driving wheel being located on the front end face and the rear end face of the mounting ring, respectively; the circumferential driven wheel includes a first circumferential driven wheel and a second circumferential driven wheel, the first circumferential driven wheel and the second circumferential driven wheel being located on the front end face and the rear end face of the mounting ring, respectively; both the first circumferential driving wheel and the second circumferential driving wheel are omnidirectional wheels, and their main rotation axes are parallel to the axis of the mounting ring; the axial motion mechanism includes an axial driving wheel rotatably connected within the mounting ring and an axial drive motor for driving the axial driving wheel to rotate, the axial driving wheel having at least a portion located within the inner space of the mounting ring, and its rotation axis being perpendicular to the axis of the mounting ring; The projections of the circumferential driving wheel, circumferential driven wheel, and axial driving wheel on the end face of the mounting ring are evenly distributed on the end face of the mounting ring; the electrical control unit controls the pressure F applied to the grinding wheel along the radial direction of the pipe by the grinding drive assembly according to the position of the grinding wheel in the circumferential direction of the pipe. 压 This causes the coupling force F between the grinding wheel and the pipe to... 耦 The system maintains a constant pressure; it includes a component mounted on the grinding wheel drive assembly for detecting and feeding back the radial pressure F applied to the grinding wheel by the grinding drive assembly. 压 The pressure sensor, the electronic control unit controls the grinding drive assembly to apply the radial pressure F to the grinding wheel in the pipeline based on the position of the grinding wheel in the circumferential direction of the pipeline. 压 And according to the formula: F 耦 =F 压 +G 磨 ×sinα×cosβ, i.e., F 压 =F 耦 -G 磨 ×sinα×cosβ, adjusting pressure F 压 The coupling force F between the grinding wheel and the pipe 耦 Always remain constant, where G 磨 Let α be the weight of the grinding wheel itself, α be the angle between the perpendicular line from the center of gravity of the grinding wheel to the axis of the pipe and the horizontal plane, and β be the angle between the axis of the pipe and the horizontal plane.

2. The nuclear power plant through-hole pipe outer wall grinding system according to claim 1, characterized in that: The axial drive wheel is an omnidirectional wheel, and the main shaft of the axial drive wheel is perpendicular to the axis of the mounting ring.

3. The nuclear power plant through-hole pipe outer wall grinding system according to claim 1, characterized in that: The grinding wheel drive assembly includes a rotary cylinder mounted on a mounting ring, a pneumatic mill mounted on the rotary cylinder's rotating shaft, and the grinding wheel mounted on the pneumatic mill's output shaft. When the rotary cylinder rotates, it drives the pneumatic mill to swing toward or away from the outer wall of the through-hole pipe.

4. The nuclear power plant through-hole pipe outer wall grinding system according to claim 1, characterized in that: The device also includes a video surveillance component.

5. The nuclear power plant through-hole pipe outer wall grinding system according to claim 4, characterized in that: The video surveillance components include cameras and lighting.

6. The nuclear power plant through-hole pipe outer wall grinding system according to claim 1, characterized in that: The device also includes a rangefinder for detecting the distance between the device and the through-hole cover.

7. The nuclear power plant through-hole pipe outer wall grinding system according to claim 1, characterized in that: The device also includes a level for detecting the angle between the device and the horizontal plane.

8. The nuclear power plant through-hole pipe outer wall grinding system according to claim 1, characterized in that: The mounting ring includes a first semi-circular ring and a second semi-circular ring, with one end of the first semi-circular ring and the second semi-circular ring rotatably connected and the other end connected by a snap fastener.

9. The nuclear power plant through-hole pipe outer wall grinding system according to claim 8, characterized in that: The buckle includes a locking pin rotatably connected to the first half-ring, a locking nut threadedly connected to the locking pin, and a spring sleeved on the locking pin and limited by the locking nut on the locking pin.

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