Reactor maintenance method, compensation ring and reactor

Abstract

The present invention relates to a reactor maintenance method, comprising: removing a worn thermowell from a tube socket; securing a compensating ring to a seat surface of the tube socket, and installing a new thermowell in the tube socket, such that the upper end surface of the compensating ring abuts against the outer contact surface of the upper end of the thermowell; or securing the compensating ring to the outer contact surface of the upper end of the new thermowell, and installing both together in the tube socket. The above-mentioned reactor maintenance method avoids replacing the tube socket or even the entire top cover, is easy to operate, and the compensating ring compensates for the worn portion of the tube socket, allowing the new thermowell to be in its working position, ensuring that the reactor pressure vessel can operate normally.

Description

Technical Field

[0001] The present invention relates to the technical field of reactor pressure equipment, in particular to a reactor maintenance method, a compensation ring and a reactor. Background Art

[0002] The reactor pressure vessel's top cover is used to seal the reactor pressure vessel. The top cover comprises an integrally formed top cover body and a tube socket. The tube socket is inserted through the top cover body, with the upper section of the tube socket positioned outside the reactor pressure vessel and the lower section positioned inside. The upper end of the tube socket is a flange surface, which is higher on the outside and lower on the inside along the tube socket's axis. A thermowell is placed within the tube socket, with the outer contact surface of the upper end of the thermowell abutting the flange surface, allowing the thermowell to be suspended within the tube socket.

[0003] A thermowell is a guide tube device used to restrict the flow of hot water within the reactor pressure vessel. When hot water flows through the thermowell, the vibrations of the water flow cause the thermowell to move axially and / or rotate circumferentially around the tube socket. As the thermowell moves or rotates, the outer contact surface rubs against the flange surface, causing friction and wear on the outer contact surface and / or flange surface. Long-term friction and wear can cause partial material loss from the outer contact surface and / or flange surface, causing the thermowell to move downward. In severe cases, the flared upper end of the thermowell can wear through and fall off. The detached portion may fall directly above the channel opening inside the thermowell, causing the control rod drive mechanism within the channel to jam and potentially trigger an emergency shutdown. Summary of the Invention

[0004] Based on this, it is necessary to provide a reactor maintenance method to address the problem that long-term friction and wear may cause partial material loss on the outer contact surface and / or flange surface, thereby causing the thermo sleeve to move downward. In severe cases, the flared upper end of the thermo sleeve may be worn through and fall off. The fallen part may fall directly above the channel opening inside the thermo sleeve, causing the control rod drive mechanism in the channel to move and become stuck, and further causing an emergency shutdown event.

[0005] An embodiment of the present application provides a reactor maintenance method, the reactor maintenance method comprising:

[0006] Remove the worn thermal sleeve inside the pipe seat;

[0007] A compensation ring and a new thermowell are provided. The compensation ring passes through the new thermowell and is arranged between the outer contact surface of the upper end of the new thermowell and the seat surface of the pipe seat to compensate for the wear and sinking between the thermowell and the pipe seat.

[0008] When treating worn thermowells and tube sockets, the above-mentioned reactor maintenance method first removes the worn thermowell and secures a compensation ring to the seat surface of the tube socket or to the outer contact surface of a newly installed thermowell. The compensation ring is positioned between the seat surface of the tube socket and the outer contact surface of the upper end of the thermowell, compensating for wear and deflection between the thermowell and tube socket. The compensated tube socket and compensation ring are used to support the upper end of a new thermowell and mate with it. This method avoids the need to replace the tube socket or even the entire top cover, and is easy to operate. Furthermore, the compensation ring compensates for wear and deflection between the thermowell and tube socket, positioning the new thermowell in its proper working position and ensuring normal operation of the reactor pressure vessel.

[0009] In one embodiment, the compensation ring is fixed to the seat surface of the pipe seat, and a new thermowell is installed in the pipe seat so that the upper end surface of the compensation ring abuts the outer contact surface of the upper end of the thermowell; or, the compensation ring is fixed to the outer contact surface of the upper end of the new thermowell, and the two are installed together in the pipe seat.

[0010] In one embodiment, the reactor maintenance method further comprises:

[0011] After the step of removing the worn thermal sleeve inside the tube seat, the seat surface of the worn tube seat is processed to form a processed surface perpendicular to the axial direction of the tube seat, the lower end surface of the compensation ring abuts against the processed surface, and the upper end surface of the compensation ring is connected to the outer contact surface of the upper end of the thermal sleeve.

[0012] In one embodiment, the thermowell includes a thermowell body and a guide cover, the upper end of the thermowell is the upper end of the thermowell body, and the lower end of the thermowell body extends out of the tube seat and is connected to the guide cover;

[0013] The steps for removing a worn thermowell from inside a pipe socket include:

[0014] Cut the connection between the guide cover and the thermowell body, and remove the thermowell body from the upper end of the tube holder.

[0015] In one embodiment, installing a new thermowell includes:

[0016] A new thermowell body is provided, and the new thermowell body is placed into the upper end of the tube seat, and then the lower end of the new thermowell body is connected to the guide cover.

[0017] An embodiment of the present application further provides a compensation ring, which is applied to the reactor maintenance method of any one of the above embodiments. The compensation ring is annular and is installed between the outer contact surface of the thermowell and the seat surface of the tube seat.

[0018] In one embodiment, the compensation ring includes a base and a support portion connected along the axial direction of the tube seat and each having a ring shape. The lower end surface of the base abuts against the processing surface, and the upper end surface of the support portion abuts against the outer contact surface of the upper end of the thermal sleeve.

[0019] In one embodiment, the base includes a plurality of separately prefabricated base parts, and the plurality of base parts are arranged to be arranged in sequence along the axial direction of the tube seat so that the base can be respectively fixed on the seat surface of the tube seat or the outer contact surface of the upper end of the new thermal sleeve.

[0020] In one embodiment, the angle between the upper end surface of the compensation ring and its central axis is 135°±2°, and the upper end surface of the compensation ring is higher on the outside and lower on the inside.

[0021] The present application further provides a reactor, which includes a reactor pressure vessel, a tube seat, a thermal sleeve, and the compensation ring of any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the reactor structure;

[0023] Figure 2 for Figure 1 Schematic diagram of the connection relationship between the center tube seat, thermal sleeve, guide cover, control rod guide tube, control rod drive mechanism and top cover body;

[0024] Figure 3 for Figure 1 Schematic diagram of the connection between the center pipe seat and the compensation ring;

[0025] Figure 4 is a flow chart of a method for maintaining a reactor in one embodiment;

[0026] Figure 5 A flowchart of dismantling ancillary equipment in one embodiment;

[0027] Figure 6 A flow chart of disengaging a control rod drive mechanism from a tube seat in one embodiment;

[0028] Figure 7 This is a flow chart of manufacturing a compensation ring according to the wear size of a tube seat in one embodiment.

[0029] Description of reference numerals:

[0030] Tube seat 110; processing surface 101;

[0031] Thermowell 120; outer contact surface 104; thermowell body 121; guide cover 122;

[0032] Compensation ring 130; upper end surface 102 of the compensation ring; lower end surface 103 of the compensation ring; base 131; support portion 132;

[0033] Top cover body 210; control rod guide tube 220; control rod drive mechanism 230. DETAILED DESCRIPTION

[0034] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are 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 understood as limiting the present invention.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0037] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0038] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0039] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0040] Please refer to Figure 1-Figure 3 In a reactor, the top cover of the reactor pressure vessel is used to seal the reactor pressure vessel. The top cover includes an integrally formed top cover body 210 and a tube seat 110, and the tube seat 110 is passed through the top cover body 210. The thermowell 120 is placed inside the tube seat 110, and the upper end of the thermowell 120 abuts against the upper end of the tube seat 110, so that the thermowell 120 is suspended inside the tube seat 110. When hot water flows through the thermowell 120, the vibration of the water flow will cause the thermowell 120 to move axially and / or rotate circumferentially along the tube seat 110. When the thermowell 120 moves or rotates, friction occurs at the abutment between the thermowell 120 and the tube seat 110, resulting in friction and wear at the abutment between the thermowell 120 and the tube seat 110. Long-term friction and wear may cause part of the material of the thermowell 120 and / or the tube seat 110 to fall off, thereby causing the thermowell 120 to move downward. In severe cases, the flared upper end of the thermowell 120 may be worn through and fall off. The fallen part may fall directly above the channel opening inside the thermowell 120, causing the control rod drive mechanism 230 in the channel to become stuck, thereby causing an emergency shutdown event.

[0041] Please refer to Figure 4 An embodiment of the present application provides a method for maintaining a reactor, the method comprising the following steps:

[0042] S110: removing the worn thermal sleeve 120 inside the tube holder 110.

[0043] Specifically, the thermowell 120 is located inside the tube base 110. Due to friction at the abutment between the thermowell 120 and the tube base 110, the thermowell 120 and / or the tube base 110 are worn to a certain extent. Therefore, the worn thermowell 120 needs to be replaced. In this case, the worn thermowell 120 first needs to be removed from the tube base 110 to leave space for installing a new thermowell 120.

[0044] S120: providing a compensation ring 130 and a new thermowell 120 , wherein the compensation ring 130 passes through the new thermowell 120 and is disposed between the outer contact surface of the upper end portion of the new thermowell 120 and the seat surface of the tube seat 110 to compensate for the wear and sinking between the original thermowell 120 and the tube seat 110 .

[0045] In step S120 , specifically, a compensation ring 130 and a new thermowell 120 may be provided. The compensation ring 130 passes through the thermowell 120 and is disposed between the outer contact surface of the upper end of the new thermowell 120 and the seat surface of the tube seat 110 to compensate for the wear and sinking between the thermowell 120 and the tube seat 110 .

[0046] In step S120, the compensation ring 130 is disposed between the outer contact surface of the upper end of the new thermowell 120 and the seat surface of the tube base 110. Specifically, the compensation ring 130 is fixed to the seat surface of the tube base 110, and the new thermowell 120 is installed in the tube base 110, so that the upper end surface 102 of the compensation ring 130 abuts the outer contact surface 104 of the upper end of the thermowell 120. Alternatively, the compensation ring 130 can be fixed to the outer contact surface 104 of the upper end of the new thermowell 120, and the two can be installed together in the tube base 110. As long as the compensation ring 130 can be installed, it will be sufficient.

[0047] Specifically, in this embodiment, a compensation ring 130 is positioned on the seat surface of the tube socket 110, and a new thermowell 120 is installed within the tube socket 110, so that the upper end surface 102 of the compensation ring 130 abuts the outer contact surface 104 of the upper end of the thermowell 120. Thus, the compensation ring 130 compensates for wear and deflection between the thermowell 120 and the tube socket 110. By providing the compensation ring 130 to compensate for wear and deflection between the thermowell 120 and the tube socket 110, the compensated tube socket 110 can support the upper end of the new thermowell 120, ensuring that the new thermowell 120 is in its operating position, thereby preventing the control rod drive mechanism 230 from becoming stuck and, in turn, preventing a scram.

[0048] In this embodiment, the compensation ring 150 may be fixed to the seat surface of the tube socket 110 by welding, or other fixing methods may be used as long as the compensation ring 150 and the seat surface of the tube socket 110 can be fixed.

[0049] In this embodiment, the compensation ring 150 can be fixed to the outer contact surface 104 of the upper end of the new thermowell 120 by welding, or other fixing methods can be used as long as the compensation ring 150 can be fixed to the outer contact surface 104 of the upper end of the new thermowell 120.

[0050] When treating a worn thermowell 120 and a worn tube socket 110, the above-described reactor maintenance method first removes the worn thermowell 120 and secures the compensation ring 130 to the seat surface of the tube socket 110 or to the outer contact surface 104 of a newly provided thermowell 120. The compensation ring 130 is positioned between the seat surface of the tube socket 110 and the outer contact surface 104 of the upper end of the thermowell 120, compensating for wear and deflection between the thermowell 120 and the tube socket 110. The compensated tube socket 110 and compensation ring 130 support the upper end of a new thermowell 120 and mate with it. This method avoids the need to replace the tube socket 110 or even the entire top cover, and is convenient to operate. Furthermore, the compensation ring 130 compensates for wear and deflection between the thermowell 120 and the tube socket 110, positioning the new thermowell 120 in its operating position and ensuring normal operation of the reactor pressure vessel.

[0051] In one embodiment, the reactor maintenance method further includes: after step S110, machining the seat surface of the worn tube socket 110 to form a machined surface 101 perpendicular to the axial direction of the tube socket 110; when the thermowell 120, the compensation ring 130, and the tube socket 110 are assembled, the lower end surface 103 of the compensation ring 130 abuts against the machined surface 101, and the upper end surface 102 of the compensation ring 130 abuts against the outer contact surface 104 of the upper end of the thermowell 120.

[0052] Specifically, by processing the seat surface of the worn tube seat 110, a processing surface 101 is formed on the seat surface which is perpendicular to the axial direction of the tube seat 110. Therefore, when the lower end surface 103 of the compensation ring 130 abuts against the processing surface 101, the lower end surface 103 of the compensation ring 130 is more closely fitted with the processing surface 101, and the lower end surface 103 of the compensation ring 130 can be more reliably abutted against the processing surface 101, thereby avoiding wear defects and unevenness of the seat surface, and preventing the compensation ring 130 from being unreliable in installation.

[0053] Please refer to Figure 7 In one embodiment, the step of machining the seat surface of the worn tube seat 110 to form a machined surface 101 perpendicular to the axial direction of the tube seat 110 includes:

[0054] S410 : grinding and shaping the seat surface of the tube seat 110 to obtain a processed surface 101 perpendicular to the axial direction of the tube seat 110 , and measuring the wear size of the worn portion of the tube seat 110 after grinding and shaping.

[0055] S420: manufacturing the compensation ring 130 according to the wear size.

[0056] Specifically, since the seat surface of the tube socket 110 is in an irregular shape after being worn and has wear defects such as pits on the surface, it is necessary to first grind and reshape the seat surface of the tube socket 110 so that the seat surface forms a processing surface 101 perpendicular to the axial direction of the tube socket 110. The processing surface 101 is smoother, making it easier to install the compensation ring 130 and to measure the dimensions that need to be compensated. After the seat surface of the tube socket 110 is ground and reshaped to form the processing surface 101, the dimensions of the processing surface 101 are measured, and the corresponding compensation ring 130 is manufactured based on the dimensions. At this time, the manufactured compensation ring 130 is adapted to the corresponding tube socket 110, and its installation and fixation on the tube socket 110 will be more stable, thereby achieving a better compensation effect on the wear of the tube socket.

[0057] In one embodiment, after step S410 , the reactor maintenance method further includes: collecting metal dust when grinding or shaping the worn areas of the tube seat 110 to ensure that no metal dust remains.

[0058] Specifically, due to the high cleanliness requirements inside the reactor pressure vessel, foreign matter such as dust may affect the safe operation of the reactor. Therefore, it is necessary to collect metal dust to ensure that no metal dust remains, thereby preventing it from affecting the safe operation of the reactor.

[0059] In one embodiment, before machining the seat surface of the worn tube socket 110 to form a machined surface 101 perpendicular to the axial direction of the tube socket 110, the reactor maintenance method further includes removing auxiliary equipment in the reactor that hinders the removal of the worn thermal sleeve 120. After step S120, the auxiliary equipment is reinstalled.

[0060] Specifically, since the reactor contains a large number of auxiliary equipment, some of the auxiliary equipment may hinder the removal of the worn thermowell 120. Therefore, before removing the worn thermowell 120, it is necessary to first remove the auxiliary equipment that hinders the removal of the worn thermowell 120, thereby exposing the tube seat 110 and facilitating the removal of the worn thermowell 120. After installing the compensation ring 130 and replacing the new thermowell 120, the removed auxiliary equipment is reinstalled to ensure normal operation of the reactor.

[0061] In this embodiment, the auxiliary equipment includes a cable tray, a seismic plate, a rod position measurement system, a drive coil assembly, and a lower enclosure of the control rod drive mechanism 230.

[0062] Please refer to Figure 5 In one embodiment, the step of removing the auxiliary equipment in the reactor that hinders the removal of the worn thermal sleeve 120 includes:

[0063] S210: Remove the cable tray.

[0064] S220: Remove the seismic plate;

[0065] S230: Remove the rod position measurement system;

[0066] S240: Remove the drive coil assembly;

[0067] S250: Remove the lower enclosure of the control rod drive mechanism 230.

[0068] The steps for disassembling the above-mentioned accessory equipment are not fixed. In actual work, it is not necessary to disassemble all of the above-mentioned accessory equipment, as long as it does not affect the removal of the worn thermal sleeve.

[0069] To reinstall the accessory equipment, follow the reverse steps.

[0070] Please refer to Figure 2 In one embodiment, the thermowell 120 includes a thermowell body 121 and a guide cover 122 . The upper end of the thermowell 120 is the upper end of the thermowell body 121 , and the lower end of the thermowell body 121 extends out of the tube seat 110 and is connected to the guide cover 122 .

[0071] The steps of removing the worn thermal sleeve 120 from the pipe base 110 include:

[0072] The connection between the guide cover 122 and the thermowell body 121 is cut, and the thermowell body 121 is removed from the tube base 110 .

[0073] Specifically, the thermowell 120 includes a thermowell body 121 and a guide cover 122. The upper end portion of the thermowell 120 is the upper end of the thermowell body 121, that is, the outer contact surface 104 of the upper end of the thermowell body 121 abuts against the tube seat 110. During friction, wear occurs at the abutment between the thermowell body 121 and the tube seat 110. The guide cover 122 does not participate in the friction process and remains intact. Therefore, only the thermowell body 121 needs to be replaced, and there is no need to replace the guide cover 122, saving time and resources.

[0074] In one embodiment, installing the new thermowell 120 includes: providing a new thermowell body 121, inserting the new thermowell body 121 from the upper end of the tube holder 110, and then connecting the lower end of the new thermowell body 121 to the guide cover 122, thereby forming a new thermowell 120 that works in conjunction with the tube holder 110.

[0075] Of course, in other optional embodiments, in the above steps, it is also possible to provide a new thermowell body 121 and a new guide cover 122 and weld them to form the thermowell 120 .

[0076] Please refer to Figure 6In one embodiment, before step S110, the reactor maintenance method further includes:

[0077] S310: Cutting the connection between the housing of the CRDM 230 and the tube seat 110 to separate the housing of the CRDM and the tube seat 110.

[0078] S320: The control rod drive mechanism 230 is transferred by a lifting device so that the worn thermal sleeve 120 and the worn pipe seat 110 are exposed.

[0079] After step S120 , the housing of the control rod drive mechanism is connected to the tube socket 110 .

[0080] Specifically, please refer to Figure 1 and Figure 2 The housing of the CRDM 230 is connected to the tube socket 110. Therefore, before removing the worn thermowell 120, the CRDM 230 must be separated from the tube socket 110 to expose the tube socket 110 and facilitate removal of the worn thermowell 120. After installing the compensation ring 130 and the new thermowell 120, the CRDM 230 can be connected to the tube socket 110 to ensure normal operation of the reactor.

[0081] In this embodiment, the housing of the CRAM 230 and the tube seat 110 are welded. Therefore, cutting the connection portion refers to cutting the weld between the housing of the CRAM 230 and the tube seat 110 .

[0082] In one embodiment, after step S110 , the reactor maintenance method further includes: transporting the worn thermal sleeve 120 into a disposal container for sealing.

[0083] Specifically, since the thermowell 120 is located inside the reactor pressure vessel and is exposed to radiation for a long time, after the worn thermowell 120 is removed, it needs to be transferred to the inside of a disposal container for processing and sealed to prevent the radiation from the worn thermowell 120 from endangering the health of workers.

[0084] In one embodiment, before installing the new thermowell 120 , the reactor maintenance method further includes: performing nondestructive testing on the new thermowell 120 , and installing it inside the tube seat 110 after the test result is qualified.

[0085] Specifically, to ensure that the new thermo-sleeve 120 can be used normally, a non-destructive test is performed on the new thermo-sleeve 120 before it is installed inside the tube base 110. If the non-destructive test result of the new thermo-sleeve 120 is qualified, the qualified new thermo-sleeve 120 is installed inside the tube base 110 to prevent problems with the new thermo-sleeve 120 from affecting the normal operation of the reactor pressure vessel.

[0086] Please refer to Figure 3 An embodiment of the present application provides a compensation ring 130, which is applied to the maintenance method of the reactor in any of the above embodiments. The compensation ring 130 is annular and is installed between the outer contact surface 104 of the thermal sleeve 120 and the seat surface of the tube seat 110.

[0087] Specifically, after the seat surface of the tube seat 110 is machined to form the machined surface 101, the lower end surface 103 of the compensation ring 130 is set on the machined surface 101, and the upper end surface 102 of the compensation ring 130 abuts against the outer contact surface 104 of the upper end of the new thermowell 120, thereby compensating for the wear of the tube seat 110 through the compensation ring 130. After the compensation ring 130 is added, it is ensured that the new thermowell 120 can be located in its working position, allowing the reactor to operate normally.

[0088] Please refer to Figure 3 In one embodiment, the compensation ring 130 includes a base 131 and a support portion 132, each of which is annular and connected along the axial direction of the tube socket 110. The lower end surface 103 of the base 131 abuts the machined surface 101, and the upper end surface 102 of the support portion 132 abuts the outer contact surface 104 of the upper end of the new thermowell 120. The base 131 and the support portion 132 may be integrally formed or separately formed and fixed together by, for example, welding or screw fastening. Specifically, because the lower end surface 103 of the base 131 abuts the machined surface 101 and the upper end surface 102 of the support portion 132 abuts the outer contact surface 104 of the upper end of the thermowell 120, the size of the base 131 along the axial direction of the tube socket 110 compensates for the wear of the tube socket 110, and the support portion 132 supports the new thermowell 120, resulting in a simple structure and easy manufacturing.

[0089] Please refer to Figure 3In one embodiment, the base 131 of the compensation ring 130 includes multiple prefabricated base portions. These base portions are arranged in sequence along the axial direction of the tube socket 110 so that the base portions can be fixed to the seat surface of the tube socket 110 or the outer contact surface of the upper end of the new thermowell 120. Specifically, the base 131 of the compensation ring 130 can be prefabricated as multiple annular base portions. Based on the wear size of the tube socket 110, an appropriate number of base portions are used to compensate for the wear, so that the base portions can be fixed to the seat surface of the tube socket 110 or the outer contact surface of the upper end of the new thermowell 120. This prefabricated multiple base portions speeds up the production of the compensation ring 130. When using the compensation ring 130, the multiple base portions can be connected, such as by welding.

[0090] In one embodiment, the compensation ring 130 includes multiple parts (not shown), which can be arranged along the circumference of the tube base 110 to form the compensation ring 130. When installing the compensation ring 130, the various parts of the compensation ring 130 can be first placed inside the tube base 110 and then connected together, such as by welding or screwing. Alternatively, the various parts can be sequentially fixed to the outer contact surface of the thermowell 120 to form the compensation ring 130 fixedly connected to the thermowell 120.

[0091] Please refer to Figure 3 In one embodiment, the angle between the upper end surface 102 of the support portion 132 and the central axis of the base 131 is 135°±2°, specifically 135°, and the upper end surface 102 of the support portion 132 is higher on the outside and lower on the inside.

[0092] In one embodiment, the compensation ring 130 is made of a metal material, such as iron, stainless steel, or other materials with sufficient wear resistance and hardness. Of course, it can also be made of other materials as long as it can compensate for the wear of the tube seat 110 and support the thermal sleeve 120.

[0093] An embodiment of the present application further provides a reactor, which includes a reactor pressure vessel, a tube seat 110 , a thermal sleeve 120 , and the compensation ring 130 of any one of the above embodiments.

[0094] When treating worn thermowells 120 and tube sockets 110, the above-described reactor maintenance method first removes the worn thermowell 120 and secures the compensation ring 130 to the seat surface of the tube socket 110 or to the outer contact surface 104 of a newly provided thermowell 120. The compensation ring 130 is positioned between the seat surface of the tube socket 110 and the outer contact surface 104 of the upper end of the thermowell 120, compensating for the wear on the tube socket 110. The compensated tube socket 110 and compensation ring 130 support the upper end of a new thermowell 120 and mate with the new thermowell 120. This method avoids the need to replace the tube socket 110 or even the entire top cover, and is convenient to operate. Furthermore, the compensation ring 130 compensates for the wear on the tube socket 110, allowing the new thermowell 120 to remain in its working position, ensuring normal operation of the reactor pressure vessel.

[0095] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for maintaining a reactor, characterized in that: The reactor maintenance method includes: Remove the worn thermal sleeve inside the pipe seat; Providing a compensation ring and a new thermowell, wherein the compensation ring passes through the new thermowell and is disposed between an outer contact surface of an upper end portion of the new thermowell and a seat surface of the tube seat to compensate for wear and sinking between the thermowell and the tube seat; The method of arranging the compensation ring in the pipe seat includes: fixing the compensation ring to the seat surface of the pipe seat by welding; or fixing the compensation ring to the outer contact surface of the upper end of the new thermal sleeve by welding; After the step of removing the worn thermowell inside the tube seat, the seat surface of the worn tube seat is processed to form a processed surface perpendicular to the axial direction of the tube seat, the lower end surface of the compensation ring abuts against the processed surface, and the upper end surface of the compensation ring is connected to the outer contact surface of the upper end of the thermowell.

2. The reactor maintenance method according to claim 1, characterized in that: The compensation ring is fixed on the seat surface of the pipe seat, and the new thermowell is installed in the pipe seat so that the upper end surface of the compensation ring abuts the outer contact surface of the upper end of the thermowell; or the compensation ring is fixed on the outer contact surface of the upper end of the new thermowell, and the two are installed together in the pipe seat.

3. The reactor maintenance method according to claim 1, characterized in that: The thermowell comprises a thermowell body and a guide cover, the upper end of the thermowell is the upper end of the thermowell body, and the lower end of the thermowell body extends out of the tube seat and is connected to the guide cover; The step of removing the worn thermal sleeve inside the pipe seat comprises: The connection between the guide cover and the thermowell body is cut, and the thermowell body is removed from the upper end of the tube seat.

4. The reactor maintenance method according to claim 3, characterized in that: Installing the new thermowell involves: A new thermowell body is provided, and the new thermowell body is placed into the upper end of the tube seat, and then the lower end of the new thermowell body is connected to the guide cover.

5. A compensation ring, characterized in that: The compensation ring is used in the maintenance method of the reactor according to any one of claims 1 to 4, wherein the compensation ring is annular and is installed between the outer contact surface of the thermowell and the seat surface of the tube seat; The compensation ring includes a base and a support portion connected along the axial direction of the tube seat and each having a ring shape, wherein the lower end surface of the base abuts against the processing surface, and the upper end surface of the support portion abuts against the outer contact surface of the upper end of the thermal sleeve; The base includes a plurality of independently prefabricated base parts, which are arranged in sequence along the axial direction of the tube seat so that the base can be fixed respectively on the seat surface of the tube seat or the outer contact surface of the upper end of the new thermal sleeve.

6. The compensation ring according to claim 5, characterized in that The included angle between the upper end surface of the compensation ring and its central axis is 135°±2°, and the upper end surface of the compensation ring is higher on the outside and lower on the inside.

7. A reactor, characterized in that: The reactor comprises a reactor pressure vessel, a tube seat, a thermal sleeve and the compensation ring according to claim 5 or 6.

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