Repair method and repair equipment for tube socket of control rod driving mechanism of nuclear reactor

Abstract

The invention discloses a nuclear reactor control rod drive mechanism tube socket repairing method and equipment, the nuclear reactor control rod drive mechanism tube socket repairing method is used for repairing a CRDM tube socket, and the nuclear reactor control rod drive mechanism tube socket repairing method comprises the following steps: using a tool to process an abraded conical surface in the CRDM tube socket to form a set surface; and a compensation piece is prepared, the compensation piece is provided with a conical bottom countersunk hole, the bottom of the compensation piece is provided with a matching face, the compensation piece is placed in the machined CRDM pipe base, the matching face abuts against the set face, the compensation piece and the machined CRDM pipe base jointly define a round hole-conical bottom countersunk head combined hole, the service life of the CRDM pipe base is prolonged, and therefore the service life of the pressure container is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power plant maintenance, and particularly relates to a method and equipment for repairing the socket of a control rod drive mechanism of a nuclear reactor. Background Art

[0002] In a reactor pressure vessel, a control rod drive mechanism (CRDM) is installed on the CRDM socket of the reactor pressure vessel head. The CRDM socket of the reactor pressure vessel head is the main component for supporting and fixing the CRDM. The end of the CRDM socket has a round hole and a countersunk conical hole communicating with the round hole to form a round hole - countersunk conical combined hole for cooperating with a thermal sleeve. The main function of the thermal sleeve is to provide a channel for the control rod drive rod. The thermal sleeve is arranged inside the CRDM socket and has a radially protruding flange portion, and the flange portion abuts against the conical surface of the countersunk conical hole.

[0003] During the operation of a nuclear power unit, due to the impact of water flow, it may cause the lower part of the thermal sleeve to swing, the entire thermal sleeve to move up and down and circumferentially, resulting in mutual wear of the conical surface portion where the lower part of the thermal sleeve flange contacts the CRDM socket, thus affecting the service life of the reactor pressure vessel head. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, the present invention provides a method for repairing the socket of a control rod drive mechanism of a nuclear reactor, which can be used to repair the CRDM socket to extend the service life of the pressure vessel head.

[0005] The present invention also provides a device for repairing the socket of a control rod drive mechanism of a nuclear reactor for the method of repairing the socket of a control rod drive mechanism of a nuclear reactor.

[0006] According to the method for repairing the socket of a control rod drive mechanism of a nuclear reactor according to the first aspect embodiment of the present invention, which is used to repair the CRDM socket, the method for repairing the socket of a control rod drive mechanism of a nuclear reactor includes the following steps:

[0007] Using a tool to machine the worn conical surface inside the CRDM socket to form a set surface;

[0008] Preparing a compensating member, the compensating member having a countersunk conical hole, and the bottom of the compensating member having a mating surface. Placing the compensating member into the machined CRDM socket and making the mating surface abut against the set surface so that the compensating member and the machined CRDM socket jointly define a round hole - conical bottom combination hole.

[0009] According to the embodiments of the present invention, it has at least the following beneficial effects:

[0010] In this embodiment, a tool is used to machine the worn conical surface in the CRDM socket to form a set surface. A compensating part is placed into the machined CRDM socket, and the mating surface is abutted against the set surface so that the compensating part and the machined CRDM socket jointly define a round hole - conical bottom counterbore combination hole, thereby extending the service life of the CRDM socket and further extending the service life of the pressure vessel.

[0011] The nuclear reactor control rod drive mechanism socket repair device according to the second aspect embodiment of the present invention is used to complete the machining of the set surface in the nuclear reactor control rod drive mechanism socket repair method. The nuclear reactor control rod drive mechanism socket repair device includes: a repair device, a locking device, a suspension bracket, and a controller.

[0012] The repair device includes a drive system and a tool. The drive system is connected to the tool and is used to drive the tool to move so as to machine the worn conical surface in the CRDM socket to form a set surface. The locking device is connected to the repair device. The locking device includes a locking member, and the locking member is used to lock the CRDM socket so that the repair device is fixed to the CRDM socket. The suspension bracket is connected to the repair device or the locking device and is used for connecting with a lifting device to lift the nuclear reactor CRDM socket repair device onto the CRDM socket. The controller is communicatively connected to the drive system, and the controller is configured to: make the locking device act to lock the CRDM socket and make the drive system act to drive the tool to move.

[0013] The nuclear reactor control rod drive mechanism socket repair device according to the embodiment of the present invention has at least the following beneficial effects:

[0014] The nuclear reactor CRDM socket repair device in this embodiment includes a suspension bracket, which is used for a lifting device to lift the CRDM socket repair device onto the CRDM socket of the pressure vessel to complete the machining of the set surface in the first aspect embodiment. The set surface is used to cooperate with the placed compensating part so that the compensating part and the machined CRDM socket jointly define a round hole - conical bottom counterbore combination hole, thereby extending the service life of the CRDM socket and further extending the service life of the pressure vessel top cover. In addition, the nuclear reactor CRDM socket repair device is lifted onto the CRDM socket through the suspension bracket, and the drive system is made to act through the controller to drive the tool to move for machining the CRDM socket, without the need to disassemble the CRDM socket from the pressure vessel. Therefore, there is no need for manual work in the radiation environment for a long time, thereby improving the operation safety.

[0015] According to some embodiments of the present invention, the drive system includes a slewing mechanism and a radial drive mechanism. The radial drive mechanism is connected to the tool and is used to drive the tool to move horizontally. The slewing mechanism is connected to the radial drive mechanism and is used to drive the radial drive mechanism to perform a circular motion around a set axis, and the set axis is parallel to the vertical direction.

[0016] According to some embodiments of the present invention, the tool includes a tool holder and a plurality of blades. The plurality of blades are connected to the tool holder around the axial direction of the tool holder. The drive system further includes a rotation mechanism, and the rotation mechanism is used to drive the tool holder to rotate around its own axis. The radial drive mechanism is connected to the rotation mechanism and is used to drive the rotation mechanism to move horizontally so as to drive the tool to move horizontally.

[0017] According to some embodiments of the present invention, the drive system further includes an axial drive mechanism. The axial drive mechanism is connected to the tool and is used to drive the tool to move in the vertical direction. The radial drive mechanism is connected to the axial drive mechanism and is used to drive the axial drive mechanism to move horizontally so as to drive the tool to move horizontally. The axial drive mechanism is connected to the rotation mechanism and is used to drive the rotation mechanism to move vertically so as to drive the tool to move vertically.

[0018] According to some embodiments of the present invention, the repair equipment for the control rod drive mechanism tube seat of the nuclear reactor further includes a dimension detection device. The dimension detection device is connected to the axial drive mechanism, and the dimension detection device is used to detect the dimensions of the set surface.

[0019] According to some embodiments of the present invention, the set surface includes a cylindrical surface, an annular plane, and an inclined surface. The outer edge of the annular plane is connected to the lower edge of the cylindrical surface, and the inclined surface is connected to the inner edge of the annular plane;

[0020] The blade includes a first blade and a second blade. The first blade is located on the radial side wall of the tool holder and is used for machining to form the cylindrical surface and the annular plane. The second blade is located at the axial end of the tool holder and is used for machining to form the inclined surface.

[0021] According to some embodiments of the present invention, the tool holder includes a first mounting portion and a second mounting portion. The first blade is connected to the first mounting portion. The first mounting portion has a mounting hole coaxial with the tool holder. The second blade is connected to the second mounting portion. The second mounting portion is installed in the mounting hole and can move and be locked relative to the first mounting portion in the vertical direction to adjust the dimension of the second blade protruding from the mounting hole.

[0022] According to some embodiments of the present invention, the second mounting portion has a first threaded hole communicating with the mounting hole, the first threaded hole is located on the side wall of the first mounting portion, the tool further includes a fastener, the fastener passes through the first threaded hole and is in threaded cooperation with the first mounting portion, and the fastener can abut against the radial side surface of the second mounting portion.

[0023] According to some embodiments of the present invention, the inner wall of the mounting hole includes a downward-facing first mounting surface, the second mounting portion has a second mounting surface facing the first mounting surface, the tool further includes a plurality of shims with different thicknesses, and each shim can be detachably arranged between the first mounting surface and the second mounting surface to adjust the size of the second blade protruding from the mounting hole.

[0024] According to some embodiments of the present invention, the first blade and the second blade are both detachably connected to the tool holder.

[0025] According to some embodiments of the present invention, the locking device further includes a connecting member and a plurality of locking members, the connecting member is connected to the repair device, the plurality of locking members are connected to the connecting member and are distributed around the set axis, and each locking member can move horizontally relative to the connecting member to press against the outer wall of the CRDM tube seat.

[0026] According to some embodiments of the present invention, the nuclear reactor control rod drive mechanism tube seat repair device further includes a protective sleeve, the protective sleeve is used to sleeve the radial outer wall of the CRDM tube seat, the protective sleeve has a second threaded hole, the second threaded hole is used to cooperate with the external thread located on the radial outer wall of the CRDM tube seat, and the locking member can abut against the protective sleeve to lock the CRDM tube seat.

[0027] According to some embodiments of the present invention, a plurality of the connecting members are connected into an integral flexible locking sleeve, the locking sleeve has a first receiving cavity for inserting the CRDM tube seat, the nuclear reactor control rod drive mechanism tube seat repair device further includes an adjusting member, the adjusting member is an annular structure, and the adjusting member can reciprocally move in the vertical direction and abut against the radial outer wall of the locking sleeve to radially contract the locking sleeve.

[0028] According to some embodiments of the present invention, the movement direction of the adjusting member when the locking member radially contracts is defined as the set direction. Along the set direction, the outer diameter of the locking member gradually increases, the inner diameter of the adjusting member gradually increases, the radial outer wall of the locking sleeve fits with the radial inner wall of the adjusting member, and the inner wall of the locking sleeve is adapted to the radial outer wall of the protective sleeve. When the adjusting member moves along the set direction and presses the locking member, causing the locking sleeve to contract, the radial inner wall of the locking sleeve can fit with the radial outer wall of the protective sleeve.

[0029] According to some embodiments of the present invention, the top of the connecting member further includes a limiting portion, the limiting portion has a downward limiting surface, and the limiting surface is used to cooperate with the top surface of the protective sleeve to make the CRDM socket vertically arranged.

[0030] According to some embodiments of the present invention, the locking device further includes at least three non-collinear positioning sensors, the positioning sensors are connected to the limiting portion, the positioning sensors include probes, and the bottom end of the probe is flush with the limiting surface. The positioning sensors are configured such that when the top surface of the protective sleeve fits with the limiting surface, the detection signals of at least three of the positioning sensors change.

[0031] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0032] The following further describes the present invention in conjunction with the drawings and embodiments, where:

[0033] Figure 1 is a schematic structural diagram of a CRDM socket in the prior art;

[0034] Figure 2 is Figure 1 a cross-sectional view of;

[0035] Figure 3 is a schematic structural diagram of a repair device for a nuclear reactor control rod drive mechanism socket according to an embodiment of the present invention;

[0036] Figure 4 is Figure 3 a cross-sectional view of;

[0037] Figure 5 is a cross-sectional view of the CRDM socket and the Figure 4 repair device for the nuclear reactor control rod drive mechanism socket in;

[0038] Figure 6 is a schematic diagram of the working condition when the repair device for the nuclear reactor control rod drive mechanism socket according to an embodiment of the present invention repairs the CRDM socket;

[0039] Figure 7 is Figure 4 a schematic structural view of the repair device in

[0040] Figure 8 is Figure 4 a schematic structural view of the cutting tool in

[0041] Figure 9 is Figure 8 a sectional view of

[0042] Figure 10 is Figure 9 an enlarged view of area A in

[0043] Figure 11 is Figure 4 a schematic structural view of the locking device in

[0044] Figure 12 is Figure 11 a sectional view of

[0045] Figure 13 is Figure 12 a schematic structural view of the locking sleeve in

[0046] Figure 14 is a schematic structural view of the CRDM nozzle after being machined by the nozzle repair equipment for nuclear reactor control rod drive mechanisms according to an embodiment of the present invention.

[0047] Reference numerals:

[0048] CRDM nozzle 10, round hole 11, tapered bottom counterbore 12, external thread 13, pressure vessel top cover 20, set surface 30, cylindrical surface 31, annular flat surface 32, inclined surface 33, control rod drive mechanism 40;

[0049] Nozzle repair equipment 1000 for nuclear reactor control rod drive mechanisms;

[0050] Repair device 100, drive system 110, slewing mechanism 111, turntable 1111, transmission cylinder 1112, radial drive mechanism 112, rotating mechanism 113, axial drive mechanism 114, cutting tool 120, tool holder 121, first mounting portion 1211, mounting hole 12111, first threaded hole 12112, first mounting surface 12113, second mounting portion 1212, second mounting surface 1213, cutting blade 122, first cutting blade 1221, second cutting blade 1222, fastener 123, gasket 124, protective cover 130;

[0051] Locking device 200, locking member 210, locking sleeve 201, clamping portion 211, deformation gap 212, first deformation gap 2121, second deformation gap 2122, connecting member 220, limiting portion 221, limiting surface 2211, adjusting member 230;

[0052] Base 300, guiding portion 310;

[0053] Hanging bracket 400, lifting ring 410, tie rod 420;

[0054] Protective sleeve 500. Detailed implementation manners

[0055] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0056] In the description of the present invention, it should be understood that for the orientation description, such as the orientation or positional relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0057] In the description of the present invention, the meaning of several is more than one, the meaning of multiple is more than two, greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0058] In the description of the present invention, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0059] In the description of the present invention, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0060] In a nuclear reactor pressure vessel, a control rod drive mechanism 40 (CRDM, Control Rod Drive Machine) is installed on a CRDM nozzle 10 on the top head of the reactor pressure vessel. The CRDM nozzle of the reactor pressure vessel top head 20 is the main component for supporting and fixing the control rod drive mechanism 40. The end of the CRDM nozzle 10 has a round hole 11 and a countersunk conical hole 12 communicating with the round hole (as Figure 1 and Figure 2 ), to form a round hole - countersunk conical combined hole for mating with a thermal sleeve. The main function of the thermal sleeve is to provide a passage for the control rod drive rod. The thermal sleeve is arranged in the CRDM nozzle 10. The thermal sleeve has a radially protruding flange portion, and the flange portion abuts against the conical surface of the countersunk conical hole.

[0061] During the operation of a nuclear power unit, due to the impact of water flow, it may cause the lower part of the thermal sleeve to swing, the entire thermal sleeve to move up and down and circumferentially, resulting in mutual wear of the conical surface part where the lower part of the thermal sleeve flange contacts the CRDM nozzle 10, thus affecting the service life of the reactor pressure vessel top head 20.

[0062] In view of the above background, the first aspect embodiment of the present invention proposes a repair method for a control rod drive mechanism nozzle of a nuclear reactor, which can be used to repair the CRDM nozzle to extend the service life of the pressure vessel.

[0063] The repair method for a control rod drive mechanism nozzle of a nuclear reactor according to the first aspect embodiment of the present invention is used to repair the CRDM nozzle. The repair method for the control rod drive mechanism nozzle of the nuclear reactor includes the following steps:

[0064] Use a tool to machine the worn conical surface in the CRDM nozzle to form a set surface 30;

[0065] Prepare a compensating part. The compensating part has a countersunk conical hole, and the bottom of the compensating part has a mating surface. Place the compensating part into the machined CRDM nozzle, and make the mating surface abut against the set surface 30, so that the compensating part and the machined CRDM nozzle jointly define a round hole - countersunk conical combined hole.

[0066] Specifically, in this embodiment, a tool is used to machine the worn conical surface inside the CRDM socket to form a set surface 30. The set surface 30 is, for example, a conical surface, a cylindrical surface - plane combined surface, or a cylindrical surface - plane - conical surface (such as Figure 13 shown), etc. As long as it can cooperate with the mating surface of the compensating part to jointly define a combined hole of a round hole - conical bottom counterbore with the machined CRDM socket, the service life of the CRDM socket can be extended, thereby extending the life of the pressure vessel top cover 20.

[0067] The CRDM socket repair device 1000 of the second - aspect embodiment of the present invention (for more concise description, hereinafter, the nuclear reactor control rod drive mechanism socket repair device 1000 will be simply referred to as the repair device 1000 unless otherwise specified) is used to complete the machining of the set surface 30 in the CRDM socket 10 repair method. Referring to Figures 3 to 6 , the repair device 1000 of this embodiment includes: a repair device 100, a locking device 200, a base 300, a suspension bracket 400, and a controller.

[0068] Among them, the repair device 100 includes a drive system 110 and a tool 120. The drive system 110 is connected to the tool 120 and is used to drive the tool 120 to move so as to machine the worn conical surface inside the CRDM socket 10 to form the set surface 30. Exemplarily, the drive system 110 includes an axial drive mechanism 114 and a rotation mechanism 113. The axial drive mechanism 114 includes a first power component and a first mounting component. The first power component is, for example, a motor, a cylinder, or a hydraulic cylinder. The first power component is connected to the first mounting component and is used to drive the first mounting component to move up and down. The rotation mechanism 113 includes a second power component. The second power component is, for example, a motor. The second power component is connected to the tool 120 and is used to drive the tool 120 to rotate. Thus, during the machining process, the axial drive mechanism 114 drives the rotation mechanism 113 downward to drive the tool 120 to move downward and contact the worn part inside the CRDM socket 10 for machining.

[0069] The locking device 200 is connected to the repair device 100. The locking device 200 includes a locking member 210. The locking member 210 is used to lock the CRDM socket 10 so that the repair device 100 is fixed to the CRDM socket 10. Exemplarily, since the pressure vessel top cover 20 usually has a plurality of CRDM sockets 10 for installing a plurality of control rod drive mechanisms 40 (such as Figure 6As shown in the figure, for example, in the CPR1000 reactor type, in addition to 61 sets of CRDMs being provided above the reactor pressure vessel head cover 20 for each unit, correspondingly 61 CRDM nozzles 10 need to be provided. Therefore, on the premise of ensuring safety requirements, the wall thickness of the CRDM nozzle 10 will not be too large, that is, the top surface space of the CRDM nozzle 10 is small. It is difficult to ensure the stability of the repair device 100 by directly placing the repair device 100 on the top surface of the CRDM nozzle 10. Based on this, in order to improve the stability of the cutting tool 120 during the machining process, in some embodiments, the locking device 200 further includes a connecting member 220 and a locking member 210. A plurality of locking members 210 are distributed around an axis extending vertically. The locking members 210 are all movably connected to the connecting member 220 and can move relative to the connecting member 220 in the horizontal direction to abut against the CRDM nozzle 10. Preferably, in some embodiments, the connecting member 220 is arranged to be located outside the CRDM nozzle 10 during the machining process to abut against the outer wall of the CRDM nozzle 10, thereby avoiding interference between the locking device 200 and the cutting tool 120, enabling the cutting tool 120 to have a larger feed space and facilitating the repair of the CRDM nozzle 10.

[0070] The hanger 400 is connected to the repair device 100 or the locking device 200 and is used for connecting to a lifting device to hoist the repair device 1000 onto the CRDM nozzle 10. Taking Figure 4 the figure shown as an example, the hanger 400 includes a lifting ring 410 and a pull rod 420. The lifting ring 410 is connected to the top of the pull rod 420, and the pull rod 420 is connected to the repair device 100, specifically the rotating mechanism 113 in the following embodiments. The controller is communicatively connected to the drive system 110. The controller is configured to: cause the locking device 200 to act to lock the CRDM nozzle 10 and cause the drive system 110 to act to drive the cutting tool 120 to move.

[0071] Specifically, the repair device 1000 in this embodiment includes a hanger 400, which is used for a lifting device to hoist the repair device 1000 onto the CRDM nozzle 10 of the reactor pressure vessel head cover 20 to complete the machining of the set surface 30 in the first aspect of the embodiment. The set surface 30 is used to cooperate with the inserted compensating part so that the compensating part and the machined CRDM nozzle 10 jointly define a round hole - countersunk conical bottom hole combination hole to extend the service life of the CRDM nozzle 10, thereby extending the service life of the reactor pressure vessel head cover 20. In addition, the repair device 1000 is hoisted onto the CRDM nozzle 10 through the hanger 400, and the drive system 110 is caused to act by the controller to drive the cutting tool 120 to move to machine the CRDM nozzle 10, without having to disassemble the CRDM nozzle 10 from the reactor pressure vessel head cover 20. Thus, there is no need for manual work in the radiation environment for a long time, thereby improving the operation safety.

[0072] As Figure 3As shown in the figure, on the basis of the above embodiments, the repair device 1000 includes a base 300. The locking device 200 is connected to the top of the base 300, and the repair device 100 is connected to the top of the locking device 200. That is, the base 300, the locking device 200, and the repair device 100 are distributed in the vertical direction, making full use of the height space and reducing the size of the repair device 1000 of this embodiment in the horizontal direction, so that the repair device 1000 of this embodiment is more suitable for working in narrow spaces (in the prior art, in order to ensure the compactness of the structure of the pressure vessel top cover 20, the gap between each CRDM nozzle 10 is small).

[0073] Further, in some embodiments, the bottom of the base 300 further includes a guiding portion 310. The guiding portion 310 has a guiding hole 311. Along the vertically downward direction, the diameter of the guiding hole gradually increases, which is beneficial for the CRDM nozzle to be inserted into the repair device 1000 of this embodiment, making the repair device 1000 of this embodiment more convenient to use.

[0074] In some embodiments, the repair device 100 further includes a protective cover 130. The drive system 110 is located inside the protective cover 130, which can not only protect the drive system 110 from dust, but also reduce the radiation received by the drive system 110, so as to extend the service life of the drive system 110, and thus extend the life of the repair device 1000 of this embodiment.

[0075] Refer to Figure 7 , Figure 7 For Figure 4 the structural schematic diagram of the repair device in Figure 7The middle protective cover is not shown. In some embodiments, the drive system 110 includes a slewing mechanism 111 and a radial drive mechanism 112. The slewing mechanism 111 is connected to the radial drive mechanism 112 and is configured to drive the radial drive mechanism 112 to perform a circular motion around a set axis, which is parallel to the vertical direction. Exemplarily, the slewing mechanism 111 includes a turntable 1111 and a second power member. The second power member is, for example, a motor. The second power member is connected to the turntable 1111 through a transmission mechanism such as a belt or a gear and is configured to drive the turntable 1111 to rotate. The radial drive mechanism 112 includes a fourth power member. The fourth power member is connected to the turntable 1111, and the turntable 1111 can drive the fourth power member to rotate. The fourth power member is, for example, a motor, a cylinder, or a hydraulic cylinder. The fourth power member is directly or indirectly connected to the tool 120. As in the above embodiment, the drive system 110 includes an axial drive mechanism 114. The fourth power member is connected to the axial drive mechanism 114 and is configured to drive the axial drive mechanism 114 to move horizontally, so as to drive the tool 120 to move horizontally. The radial drive mechanism 112 is connected to the tool 120. Therefore, during the machining process, the tool 120 can be driven by the radial drive mechanism 112 to move radially to adjust the machining radius of the tool 120. Thus, cylindrical surfaces with various different diameters can be machined to serve as the set surface 30, thereby improving the practicability of the CRDM repair device in this embodiment. In addition, a small tool 120 can be used to machine a large round hole 11 to reduce the weight of the tool 120, thereby improving the stability of the tool 120 during machining and improving the stability of the tool 120 during movement. At the same time, since the tool 120 is smaller, the risk of the tool 120 bumping against the CRDM socket 10 can be reduced when the tool 120 extends into the CRDM socket 10.

[0076] Referring to Figure 5 , on the basis of the above embodiment, the slewing mechanism 111 includes a second power member, a transmission assembly, and a transmission cylinder 1112. The second power member is in transmission connection with the transmission cylinder 1112 through the transmission assembly. The turntable 1111 is connected above the transmission cylinder 1112. The transmission cylinder 1112 has a second accommodation cavity. The locking device 200 is located in the second accommodation cavity, that is, the space occupied by the locking device 200 and the transmission cylinder 1112 overlaps in the horizontal direction without requiring additional space, so as to reduce the size of the repair device 1000 in the horizontal direction in this embodiment. Thus, it is more conducive to repairing the CRDM socket 10 in a narrow space.

[0077] Furthermore, the second power component is a motor, and the transmission assembly includes a first transmission wheel, a belt, a second transmission wheel, a connecting rod, and a third transmission wheel. The second power component is connected to the base 300 and is vertically arranged. The first transmission wheel is located below the second power component and is connected to the second power component. The second transmission wheel is rotatably connected to the base 300 and is located below the transmission cylinder 1112. The second transmission wheel is within the vertical projection range of the transmission cylinder 1112. The belt connects the first transmission wheel and the second transmission wheel. The connecting rod is vertically arranged, with one end connected to the second transmission wheel and the other end connected to the third transmission wheel. The inner wall of the transmission cylinder 1112 has internally teeth arranged in a surrounding manner, and the second transmission wheel meshes with the internal teeth. Thus, the transmission cylinder 1112 can be driven to rotate by the second power component, thereby driving the turntable 1111 to rotate. It can be known that in this embodiment, the connecting rod and the third transmission wheel are located inside the second accommodation cavity, that is, the space occupied by the transmission assembly and the transmission cylinder 1112 partially overlaps in the horizontal direction, further reducing the size of the repair device 1000 in the horizontal direction of this embodiment, thus being more conducive to operation in a narrow space.

[0078] Referring to Figure 8 , on the basis of the above embodiment, the tool 120 includes a tool holder 121 and a plurality of cutting blades 122. The plurality of cutting blades 122 are connected to the tool holder 121 around the axial direction of the tool holder 121. The drive system 110 further includes a rotating mechanism 113. The rotating mechanism 113 is used to drive the tool holder 121 to rotate around its own axial direction. The radial drive mechanism 112 is connected to the rotating mechanism 113 and is used to drive the rotating mechanism 113 to move horizontally, so as to drive the tool 120 to move horizontally. Specifically, during the machining process, the tool 120 not only rotates around a set axis in a revolution manner but also rotates around its own axis. Thus, the forces on each direction of the tool 120 tend to be consistent, thereby avoiding deformation or damage of the tool 120 due to long-term single-direction force, so as to extend the service life of the tool 120. In addition, the plurality of cutting blades 122 alternately machine the CRDM socket 10, which can reduce the wear of each tool 120 and further extend the service life of the tool 120.

[0079] Referring to Figure 7, in some embodiments, the drive system 110 further includes an axial drive mechanism 114. The axial drive mechanism 114 is connected to the tool 120 and is configured to drive the tool 120 to move in the vertical direction. The radial drive mechanism 112 is connected to the axial drive mechanism 114 and is configured to drive the axial drive mechanism 114 to move horizontally, so as to drive the tool 120 to move horizontally. The axial drive mechanism 114 is connected to the rotation mechanism 113 and is configured to drive the rotation mechanism 113 to move vertically, so as to drive the tool 120 to move vertically. Specifically, since the axial drive mechanism 114 can drive the tool 120 to move in the vertical direction, when the CRDM socket 10 repair device of this embodiment is hoisted to the CRDM socket 10, the tool 120 can be lifted to the highest position, thereby avoiding bumping into the tool 120 when being locked and fixed with the CRDM socket 10, and thus preventing the CRDM socket 10 from being damaged, so as to improve the safety of the pressure vessel top cover 20 during operation.

[0080] Referring to Figure 5 , in some embodiments, the repair device 1000 further includes a dimension detection device 600. The dimension detection device 600 is connected to the axial drive mechanism 114. The dimension detection device 600 is, for example, a ruby probe. After the machining is completed, the travel of the tool 120 in the vertical and horizontal directions during machining can be measured, so as to determine the dimensions of the machined limiting surface 2211, thereby improving the machining accuracy of the setting surface 30. For example, a circular repair hole is machined at the worn part of the CRDM during machining for mating with the compensating part, that is, the setting surface 30 is the side wall surface and the bottom wall surface of the circular repair hole (unless otherwise specified, the same hereinafter). After the machining is completed, the detection device 600 is driven by the drive system 110 to move downward from the initial machining height. When the dimension detection device 600 contacts the bottom wall surface, the distance measured by the dimension detection device 600 is the depth of the circular repair hole. The dimension detection device 600 is driven by the drive system 110 to move horizontally. When the dimension detection device 600 contacts the side wall for the first time, it is the first marking point. Then the detection device 600 is moved in the reverse direction. When the detection device 600 contacts the side wall again, it is the second marking point. The distance between the two marking points is the diameter of the circular repair hole. In addition, in order to improve the detection accuracy, each dimension can be measured multiple times and the average value can be obtained.

[0081] Referring to Figure 8 and Figure 14, in some embodiments, the setting surface 30 includes a cylindrical surface 31 (the cylindrical surface 31 is not limited to having the same diameter as the circular hole 11 at the end of the CRDM socket 10), an annular plane 32, and an inclined surface 33. The outer edge of the annular plane 32 is connected to the lower edge of the cylindrical surface 31, and the inclined surface 33 is connected to the inner edge of the annular plane 32. That is, both a circular repair hole needs to be machined and chamfering is required. Based on this, the blade 122 includes a first blade 1221 and a second blade 1222. The first blade 1221 is located on the radial side wall of the tool holder 121 and is used to machine the cylindrical surface 31 and the annular plane 32. The second blade 1222 is located at the axial end of the tool holder 121 and is used to machine the inclined surface 33. Therefore, during the machining process, a circular repair hole and chamfering can be machined simultaneously without the need for step-by-step machining, so as to improve the machining efficiency of the repair device 1000 in this embodiment, thereby shortening the working time of the device in the radiation environment and extending the life of the device.

[0082] Based on the above embodiments, both the first blade 1221 and the second blade 1222 are detachably connected to the tool holder 121. Specifically, since the parts machined by the first blade 1221 and the second blade 1222 are different and the shapes machined are different, there are certain differences in their wear degrees. Since both the first blade 1221 and the second blade 1222 are detachably connected to the tool holder 121 in this embodiment, when the first blade 1221 is worn, the first blade 1221 can be replaced separately. Similarly, when the second blade 1222 is worn, the second blade 1222 can be replaced separately without replacing the entire tool 120, thus saving the repair cost.

[0083] Refer to Figure 8 and Figure 9, in some embodiments, the tool holder 121 includes a first mounting portion 1211 and a second mounting portion 1212. The first blade 1221 is connected to the first mounting portion 1211. The first mounting portion 1211 has a mounting hole 12111 coaxial with the tool holder 121. The second blade 1222 is connected to the second mounting portion 1212. The second mounting portion 1212 is detachably disposed within the mounting hole 12111 and can move and lock relative to the first mounting portion 1211 in the vertical direction to adjust the size of the second blade 1222 protruding from the mounting hole 12111. For example, in some embodiments, the second mounting portion 1212 has a first threaded hole 12112 communicating with the mounting hole 12111. The first threaded hole 12112 is located on the side wall of the first mounting portion 1211. The tool 120 further includes a fastener 123. The fastener 123 passes through the first threaded hole 12112 and is in threaded cooperation with the first mounting portion 1211. The fastener 123 can abut against the radial side surface of the second mounting portion 1212, thereby locking the second mounting portion 1212 and making the locking structure of the tool 120 simpler. Specifically, it can be understood that the second blade 1222 is used for chamfering, and its cutting edge is necessarily inclined with respect to the axis of the tool 120 itself. Therefore, by vertically moving the second mounting portion 1212, the size of the cutting edge of the second blade 1222 protruding from the mounting hole 12111 can be adjusted, thereby adjusting the horizontal contact position of the second blade 1222 with the CRDM pipe seat 10 to adjust the size of the chamfered inclined surface 33. Therefore, the repair device 1000 of this embodiment can process inclined surfaces 33 of different sizes through the relative movement of the first mounting portion 1211 and the second mounting portion 1212, thereby improving the practicability of the repair device 1000 of this embodiment.

[0084] Refer to Figure 9 and Figure 10 , in some embodiments, the inner wall of the mounting hole 12111 has a downward first mounting surface 12113, and the second mounting portion 1212 has a second mounting surface 1213 facing the first mounting surface 12113. The tool 120 further includes a plurality of shims 124 with different thicknesses. Each shim 124 can be detachably disposed between the first mounting surface 12113 and the second mounting surface 1213 to adjust the size of the second blade 1222 protruding from the mounting hole 12111. It can be known from this that in this embodiment, not only the positions of the first mounting portion 1211 and the second mounting portion 1212 are limited by the fastener 123, but also the position accuracy of the first mounting portion 1211 and the second mounting portion 1212 is further improved by the shims 124, preventing the second mounting portion 1212 from moving relative to the first mounting portion 1211 due to the axial pressure during the processing, so as to improve the processing accuracy of the second blade 1222, thereby improving the processing accuracy of the inclined surface 33 and improving the processing accuracy of the CRDM pipe seat 10.

[0085] Refer toFigure 4 and Figure 12 It can be understood that the outer wall of the CRDM tube seat 10 also has an external thread 13 that cooperates with the control rod drive mechanism 40. In order to prevent the external thread 13 from being crushed, in some embodiments, the repair device 1000 also includes a protective sleeve 500, which is used to be sleeved on the radial outer wall of the CRDM tube seat 10. The protective sleeve 500 has a second threaded hole 510, and the second threaded hole 510 is used to cooperate with the external thread 13 located on the radial outer wall of the CRDM tube seat 10. Therefore, during the processing, the locking member 210 abuts against the outer wall of the protective sleeve 500 to lock the CRDM tube seat 10. It does not need to contact the external thread 13 of the CRDM tube seat 10, thereby reducing the risk of the external thread 13 of the CRDM tube seat 10 being crushed.

[0086] Reference Figure 3 , Figure 4 , Figures 11 to 13 In some embodiments, a plurality of locking members 210 are connected to form an integrated flexible locking sleeve 201, the locking sleeve 201 has a first accommodating cavity, and the first accommodating cavity is used for inserting the CRDM pipe seat 10. The repair device 1000 also includes an adjusting member 230, which is an annular structure. The adjusting member 230 can reciprocate in the vertical direction and abut against the radial outer wall of the locking sleeve 201 to make the locking sleeve 201 contract radially to lock the CRDM pipe seat 10. For example, the locking sleeve 201 is tightly attached to the outer wall of the CRDM pipe seat 10, or when the protective sleeve 500 is further included in the above embodiment, the locking sleeve 201 is tightly attached to the outer wall of the protective sleeve 500 to increase the force-bearing area of ​​the protective sleeve 500, thereby improving the locking stability. In addition, since a plurality of locking members 210 are connected to form an integrated structure, they can be driven by fewer power members (fifth power members), so that the repair device 1000 of this embodiment has smaller gravity and volume, which is conducive to high-altitude and narrow space operations. Specifically, for example, the locking sleeve 201 is formed by connecting eight locking members 210. If the locking members 210 are split structures, eight adjusting members 230 and eight fifth power members are required. In this embodiment, the eight locking members 210 are connected as an integral structure, which only requires one adjusting member 230 and is driven by relatively fewer fifth power members. The fifth power members are, for example, one, two or three (such as Figure 11 As shown), as long as the number of the fifth power members is less than the number of the locking members 210, it will be sufficient.

[0087] Reference Figure 13, on the basis of the above embodiments, the locking sleeve 201 includes a plurality of deformation gaps 212. The plurality of deformation gaps 212 are circumferentially spaced apart along the locking sleeve 201. The deformation gaps 212 penetrate the locking sleeve 201 radially to improve the deformation ability of the locking sleeve 201. Further, the deformation gaps 212 include a first deformation gap 2121 and a second deformation gap 2122. Along the circumference of the locking sleeve 201, the first deformation gap 2121 and the second deformation gap 2122 are alternately distributed. The first deformation gap 2121 has an upward opening, and the second deformation gap 2122 has a downward opening, improving the consistency of the elasticity at the upper and lower ends of the locking sleeve 201, so that the upper and lower parts of the locking sleeve 201 contract uniformly, thereby enhancing the locking strength and strengthening the stability of the repair device 1000, and thus improving the stability of the tool 120.

[0088] Referring to Figure 12 , on the basis of the above embodiments, the connecting member 220 includes an annular clamping groove 222. The clamping groove 222 has an opening radially inward. The locking sleeve 201 includes a radially outward clamping portion 211. The clamping portion 211 is movably clamped in the clamping groove 222 to prevent the locking sleeve 201 from falling off.

[0089] Referring to Figure 12 , in some embodiments, define the movement direction of the adjusting member 230 when the locking sleeve 201 radially contracts as the set direction (such as the vertically upward direction in the attached drawing). Along the set direction, the outer diameter of the locking sleeve 201 gradually increases, and the inner diameter of the adjusting member 230 is smaller than the maximum value of the outer diameter of the locking sleeve 201. Thus, during the movement of the adjusting member 230 along the set direction, the adjusting member 230 will squeeze the outer wall of the locking sleeve 201 to make the locking sleeve 201 contract. Or, in some embodiments, along the set direction, the inner diameter of the adjusting member 230 gradually increases, and the outer diameter of the locking sleeve 201 is larger than the minimum value of the inner diameter of the adjusting member 230. Therefore, during the movement of the adjusting member 230 along the set direction, the adjusting member 230 will squeeze the outer wall of the locking sleeve 201 to make the locking sleeve 201 contract.

[0090] Or, in some embodiments, along the set direction, the outer diameter of the locking sleeve 201 gradually increases, the inner diameter of the adjusting member 230 gradually increases, and the radial outer wall of the locking sleeve 201 fits with the radial inner wall of the adjusting member 230, increasing the contact area between the adjusting member 230 and the locking sleeve 201. This can not only make the force on the locking sleeve 201 more uniform, but also increase the contact area between the locking sleeve 201 and the adjusting member 230, thereby reducing the pressure between the locking sleeve 201 and the adjusting member 230, reducing the wear between the locking sleeve 201 and the adjusting member 230, and thus extending the service life of the repair device 1000 in this embodiment.

[0091] Referring to Figure 5 and Figure 12, in some embodiments, the top of the connecting member 220 further includes a limiting portion 221. The limiting portion 221 has a downward-facing limiting surface 2211. The limiting surface 2211 is used to cooperate with the top surface of the protective sleeve 500 to keep the CRDM socket 10 vertical, so as to improve the machining accuracy of the CRDM socket 10. Specifically, for example, during machining, a circular repair hole is formed at the worn part of the CRDM socket 10 for cooperation with the compensating member. That is, the setting surface 30 is the side wall surface and the bottom wall surface of the circular repair hole. The top surface of the protective sleeve 500 is a plane perpendicular to the axis of the CRDM socket 10. Therefore, when the CRDM socket 10 is inserted into the repair device 1000 of this embodiment, the top surface of the protective sleeve 500 will contact the limiting surface 2211, and by adjusting the pose of the repair device 1000 of this embodiment, the limiting surface 2211 is made to fit the top surface of the protective sleeve 500, so that the CRDM socket 10 is in a vertical state, thereby improving the machining accuracy of the setting surface 30 and thus improving the repair accuracy of the CRDM socket 10.

[0092] Refer to Figure 11 and Figure 12 , in some embodiments, the locking device 200 further includes at least three non-collinear positioning sensors 240. The positioning sensors 240 are connected to the limiting portion 221. The positioning sensors 240 include probes 241. The bottom end of the probe 241 is flush with the limiting surface 2211. The positioning sensors 240 are configured such that when the top surface of the protective sleeve 500 fits the limiting surface 2211, the detection signals of at least three positioning sensors 240 change. Specifically, three points in space determine a plane. Therefore, when the detection signals of three non-collinear positioning sensors 240 all change, it indicates that the top surface of the protective sleeve 500 fits the limiting surface 2211, that is, it indicates that the CRDM socket 10 is in a vertical state at this time, without the need for manual judgment, reducing the error caused by human factors, thereby improving the repair accuracy of the CRDM socket 10.

[0093] The embodiments of the present invention have been described in detail above with reference to the drawings. However, the present invention is not limited to the above embodiments. Various changes can be made without departing from the spirit of the present invention within the knowledge scope of those of ordinary skill in the art. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. A method for repairing a control rod drive mechanism tube seat of a nuclear reactor, characterized in that: Used to repair the CRDM tube seat, the nuclear reactor control rod drive mechanism tube seat repair method comprises the following steps: Using a tool to process the worn conical surface in the CRDM pipe seat to form a setting surface; Prepare a compensating part, wherein the compensating part has a conical bottom countersunk hole, and the bottom of the compensating part has a mating surface. Place the compensating part into the processed CRDM tube seat, and make the mating surface abut against the set surface, so that the compensating part and the processed CRDM tube seat jointly define a circular hole-conical bottom countersunk combination hole.

2. Nuclear reactor control rod drive mechanism tube seat repair equipment, characterized in that: Used to complete the processing of the set surface in the nuclear reactor control rod drive mechanism tube seat repair method, the nuclear reactor control rod drive mechanism tube seat repair equipment includes: A repair device, comprising a drive system and a tool, wherein the drive system is connected to the tool and is used to drive the tool to move so as to machine the worn conical surface in the CRDM tube seat to form a setting surface; A locking device connected to the repair device, the locking device comprising a locking member, the locking member being used to lock the CRDM tube seat so that the repair device is fixed to the CRDM tube seat; A hanger, connected to the repair device or the locking device, and used for connection with a lifting device to lift the nuclear reactor control rod drive mechanism tube seat repair device onto the CRDM tube seat; A controller is in communication with the drive system and the locking device, and the controller is configured to: activate the locking device to lock the CRDM tube seat, and activate the drive system to drive the tool to move.

3. The nuclear reactor control rod drive mechanism tube seat repair equipment according to claim 2, characterized in that: The driving system includes a rotary mechanism and a radial driving mechanism. The radial driving mechanism is connected to the tool and is used to drive the tool to move horizontally. The rotary mechanism is connected to the radial driving mechanism and is used to drive the radial driving mechanism to move in a circle around a setting axis, and the setting axis is parallel to the vertical direction.

4. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 3, characterized in that: The tool includes a tool holder and a plurality of blades, wherein the plurality of blades are connected to the tool holder around the axial direction of the tool holder. The drive system also includes a rotating mechanism, which is used to drive the tool holder to rotate around its own axial direction. The radial drive mechanism is connected to the rotating mechanism and is used to drive the rotating mechanism to move horizontally, thereby driving the tool to move horizontally.

5. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 4, characterized in that: The drive system also includes an axial drive mechanism, which is connected to the tool and used to drive the tool to move in a vertical direction. The radial drive mechanism is connected to the axial drive mechanism and used to drive the axial drive mechanism to move horizontally to drive the tool to move horizontally. The axial drive mechanism is connected to the rotating mechanism and used to drive the rotating mechanism to move vertically to drive the tool to move vertically.

6. The nuclear reactor control rod drive mechanism tube seat repair equipment according to claim 5, characterized in that: The nuclear reactor control rod drive mechanism socket repairing equipment further comprises a size detection device, which is connected to the axial drive mechanism and is used to detect the size of the set surface.

7. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 4, characterized in that: The setting surface includes a cylindrical surface, an annular plane and an inclined surface, wherein the outer edge of the annular plane is connected to the lower edge of the cylindrical surface, and the inclined surface is connected to the inner edge of the annular plane; The blade comprises a first blade and a second blade, wherein the first blade is located on the radial side wall of the blade seat and is used for machining to form the cylindrical surface and the annular plane, and the second blade is located on the axial end of the blade seat and is used for machining to form the inclined surface.

8. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 7, characterized in that: The knife seat includes a first mounting portion and a second mounting portion, the first blade is connected to the first mounting portion, the first mounting portion has a mounting hole coaxial with the knife seat, the second blade is connected to the second mounting portion, the second mounting portion is installed in the mounting hole, and can be moved and locked in a vertical direction relative to the first mounting portion to adjust the size of the second blade protruding from the mounting hole.

9. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 8, characterized in that: The second mounting portion has a first threaded hole connected to the mounting hole, and the first threaded hole is located on the side wall of the first mounting portion. The tool also includes a fastener, which is passed through the first threaded hole and threadedly matched with the first mounting portion. The fastener can be tightened against the radial side of the second mounting portion.

10. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 9, characterized in that: The inner wall of the mounting hole includes a first mounting surface facing downward, the second mounting portion has a second mounting surface facing the first mounting surface, and the tool also includes a plurality of gaskets of different thicknesses, each of which can be detachably arranged between the first mounting surface and the second mounting surface to adjust the size of the second blade protruding from the mounting hole.

11. The nuclear reactor control rod drive mechanism tube seat repair equipment according to claim 7, characterized in that: The first blade and the second blade can be detachably connected to the blade holder.

12. The nuclear reactor control rod drive mechanism tube seat repair equipment according to claim 3, characterized in that: The locking device also includes a connecting member and a plurality of locking members, wherein the connecting member is connected to the repair device, and the plurality of locking members are connected to the connecting member and are distributed around the set axis, and each locking member can move horizontally relative to the connecting member to press the outer wall of the CRDM tube seat.

13. The nuclear reactor control rod drive mechanism tube seat repair equipment according to claim 12, characterized in that: The nuclear reactor control rod drive mechanism tube seat repair equipment also includes a protective sleeve, which is used to be sleeved on the radial outer wall of the CRDM tube seat. The protective sleeve has a second threaded hole, and the second threaded hole is used to cooperate with the external thread located on the radial outer wall of the CRDM tube seat. The locking piece can abut against the protective sleeve to lock the CRDM tube seat.

14. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 13, characterized in that: A plurality of the connecting parts are connected to form an integral flexible locking sleeve, wherein the locking sleeve has a first accommodating cavity, and the first accommodating cavity is used for inserting the CRDM tube seat. The nuclear reactor control rod drive mechanism tube seat repair equipment also includes an adjusting member, which is an annular structure. The adjusting member can reciprocate in the vertical direction and abut against the radial outer wall of the locking sleeve to cause the locking sleeve to contract radially.

15. The nuclear reactor control rod drive mechanism tube seat repair equipment according to claim 14, characterized in that: The movement direction of the adjusting member when the locking member contracts radially is defined as a set direction. Along the set direction, the outer diameter of the locking member gradually increases, the inner diameter of the adjusting member gradually increases, the radial outer wall of the locking sleeve fits with the radial inner wall of the adjusting member, and the inner wall of the locking sleeve fits with the radial outer wall of the protective sleeve. When the adjusting member moves along the set direction and squeezes the locking member to contract the locking sleeve, the radial inner wall of the locking sleeve can fit with the radial outer wall of the protective sleeve.

16. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 13, characterized in that: The top of the connector also includes a limiting portion, and the limiting portion has a limiting surface facing downward, and the limiting surface is used to cooperate with the top surface of the protective sleeve to enable the CRDM tube seat to be vertically arranged.

17. The nuclear reactor control rod drive mechanism socket repair equipment according to claim 16, characterized in that: The locking device also includes at least three positioning sensors that are not arranged in a colinear manner. The positioning sensors are connected to the limiting portion. The positioning sensors include a probe, and the bottom end of the probe is flush with the limiting surface. The positioning sensors are configured such that when the top surface of the protective cover is in contact with the limiting surface, the detection signals of at least three of the positioning sensors change.

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