Position monitoring system and arrangement method for nuclear instrument of nuclear power plant

Abstract

The invention provides a position monitoring system for a nuclear instrument of a nuclear power plant and an arrangement method. The position monitoring system comprises a guide cylinder, a first position monitoring unit, a second position monitoring unit and an upper computer. The guide cylinder is pre-buried at the periphery of a reactor pressure vessel, and a mounting channel for nuclear instruments to pass through is arranged in the guide cylinder; the first position monitoring unit is used for monitoring the current position of the nuclear instrument in real time, is arranged on the side wall of the guide cylinder and corresponds to the upper side of the working position of the nuclear instrument; the second position monitoring unit is used for monitoring the current position of the nuclear instrument in real time, is arranged on the side wall of the guide cylinder and corresponds to the lower side of the working position of the nuclear instrument; and the upper computer is in communication connection with the first position monitoring unit and the second position monitoring unit and is used for acquiring the current position of the nuclear instrument monitored by the first position monitoring unit and the second position monitoring unit in real time. The nuclear instrument installation precision requirement can be met, and the arrangement efficiency is improved.

Description

A position monitoring system and layout method for nuclear instruments in nuclear power plants Technical Field

[0001] This invention relates to the field of nuclear power plant technology, and in particular to a position monitoring system and arrangement method for nuclear instruments in a nuclear power plant. Background Technology

[0002] Nuclear instruments are a series of neutron detectors distributed outside the reactor pressure vessel, used to measure reactor power, power change rate, and radial and axial power distribution. They are among the most important instruments directly related to reactor safety. To comprehensively measure reactor power, measurement points need to be set up radially and axially along the reactor core: for example, at the upper half, center, and lower half of the core axis. The instruments must be accurately positioned at these measurement points. However, currently, when arranging nuclear instruments, operators mostly rely on theoretical calculations and manual experience, using mechanical devices or cranes to install the instruments at the measurement points. This makes it difficult to meet the required installation accuracy, resulting in poor measurement data accuracy, hindering core management. Furthermore, when different operators arrange the same measurement point, the position drift is significant, requiring repeated adjustments, which is time-consuming, inefficient, and poses radiation risks. Summary of the Invention

[0003] This invention provides a position monitoring system and layout method for nuclear instruments in nuclear power plants, which can meet the installation accuracy requirements of nuclear instruments and improve layout efficiency.

[0004] This invention provides a position monitoring system for nuclear instruments in a nuclear power plant, comprising: a guide cylinder, a first position monitoring unit, a second position monitoring unit, and a host computer.

[0005] The guide tube is pre-embedded around the reactor pressure vessel, and an installation channel for nuclear instruments is provided inside the guide tube; the first position monitoring unit is used to monitor the current position of the nuclear instruments in real time, and is set on the side wall of the guide tube and above the working position of the nuclear instruments; the second position monitoring unit is used to monitor the current position of the nuclear instruments in real time, and is set on the side wall of the guide tube and below the working position of the nuclear instruments; the host computer communicates with the first position monitoring unit and the second position monitoring unit to obtain the current position of the nuclear instruments monitored by the first position monitoring unit and the second position monitoring unit in real time.

[0006] In one embodiment of the present invention, the first position monitoring unit is a position switch.

[0007] In one embodiment of the present invention, the position switch includes at least one inductive position switch and at least one mechanical position switch, wherein the inductive position switch and the mechanical position switch are arranged circumferentially along the side wall of the guide cylinder.

[0008] In one embodiment of the present invention, there are two inductive position switches and two mechanical position switches, and the two inductive position switches and the two mechanical position switches are arranged symmetrically.

[0009] In one embodiment of the present invention, the second position monitoring unit has the same structure as the first position monitoring unit.

[0010] In one embodiment of the present invention, the position monitoring system further includes a display, which is communicatively connected to a host computer for displaying the current position of the nuclear instrument in real time.

[0011] In one embodiment of the present invention, the side wall of the guide cylinder is provided with a groove extending along the length direction, and a cable is threaded through the groove. The first position monitoring unit and the second position monitoring unit are both connected to the host computer via the cable.

[0012] In one embodiment of the present invention, the host computer includes a digital signal processing cabinet, which is communicatively connected to a first position monitoring unit and a second position monitoring unit.

[0013] The present invention also provides a method for arranging nuclear instruments using the above-mentioned position monitoring system, comprising: marking the upper and lower sides of the working position of the nuclear instrument on the side wall of the guide tube; arranging a first position monitoring unit on the upper side of the working position of the nuclear instrument; arranging a second position monitoring unit on the lower side of the working position of the nuclear instrument; pre-embedding the guide tube around the reactor pressure vessel; moving the nuclear instrument downward along the installation channel of the guide tube; when the lower side of the nuclear instrument reaches the elevation of the first position monitoring unit, the host computer obtains the current position of the nuclear instrument monitored by the first position monitoring unit; continuing to move the nuclear instrument downward along the installation channel of the guide tube; when the lower side of the nuclear instrument reaches the elevation of the second position monitoring unit, the host computer obtains the current position of the nuclear instrument monitored by the second position monitoring unit; at this time, the nuclear instrument reaches the working position, and the arrangement of the nuclear instrument is completed.

[0014] In one embodiment of the present invention, a lifting device is used to move nuclear instruments downward along the installation channel of the guide tube using a wire rope.

[0015] The beneficial effects of this invention are as follows: This invention relates to a position monitoring system and arrangement method for nuclear instruments in nuclear power plants. The position monitoring system includes a guide tube, a first position monitoring unit, a second position monitoring unit, and a host computer. During the arrangement of nuclear instruments, it is only necessary to move the nuclear instruments downwards along the installation channel of the guide tube. When the lower side of the nuclear instrument reaches the elevation of the first position monitoring unit, the operator can immediately remotely obtain the current position of the nuclear instrument monitored by the first position monitoring unit. When the lower side of the nuclear instrument reaches the elevation of the second position monitoring unit, the operator can immediately remotely obtain the current position of the nuclear instrument monitored by the second position monitoring unit. At this point, the nuclear instruments have reached their working positions, completing the instrument deployment. By setting up a first position monitoring unit and a second position monitoring unit that communicate with the host computer, the dual monitoring unit design improves the reliability of position monitoring, increases the number of measurable elevations, and allows operators to obtain the position information of the nuclear instruments more promptly and accurately without relying on theoretical calculations and manual experience. This achieves full informatization of the nuclear instrument deployment process, meets the installation accuracy requirements of the nuclear instruments, more accurately measures reactor power, improves deployment efficiency, and avoids having installation personnel go to detector deployment sites with poor environmental conditions and high radiation doses, reducing radiation risks. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0017] In the accompanying drawings: Figure 1 is a schematic diagram of the overall structure of a position monitoring system for nuclear instruments in a nuclear power plant according to an embodiment of the present invention; Figure 2 is a schematic diagram of the longitudinal section of the first position monitoring unit in Figure 1 along the 1-1 direction according to an embodiment of the present invention; Figure 3 is a schematic diagram of the longitudinal section of the second position monitoring unit in Figure 1 along the 2-2 direction according to an embodiment of the present invention.

[0018] The attached diagram is labeled as follows: 1. Guide tube; 11. Installation channel; 12. Cable tray; 2. Pressure vessel of the reactor to be monitored; 21. Reactor core; 3. Nuclear instrument; 4. First position monitoring unit; 41. Inductive position switch; 42. Mechanical position switch; 5. Second position monitoring unit; 51. Inductive position switch; 52. Mechanical position switch; 6. Host computer; 61. Digital signal processing cabinet; 7. Display; 8. Cable; 9. Steel wire rope. Detailed Implementation

[0019] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0021] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0022] Please refer to Figures 1 to 3. The present invention provides a position monitoring system for nuclear instruments in a nuclear power plant, comprising: a guide cylinder 1, a first position monitoring unit 4, a second position monitoring unit 5, and a host computer 6.

[0023] Please refer to Figures 1 to 3. The guide cylinder 1 is pre-embedded around the reactor pressure vessel 2 (i.e., around the reactor core 21). The guide cylinder 1 has an installation channel 11 for the nuclear instruments 3 to pass through. The guide cylinder 1 serves as a guiding structure for the installation of the nuclear instruments 3, ensuring that the nuclear instruments 3 can be accurately installed in their predetermined working positions. In specific implementations, the guide cylinder 1 can be pre-embedded within the surrounding shielding wall of the reactor pressure vessel 2 to reduce signal attenuation and electromagnetic interference risks, and improve communication stability. The cross-section of the guide cylinder 1 can adopt conventional shapes readily conceived by those skilled in the art, including but not limited to circles, squares, and irregular shapes.

[0024] Please refer to Figures 1 to 3. The first position monitoring unit 4 is used to monitor the current position of the nuclear instrument 3 in real time. It is set on the side wall of the guide cylinder 1 and corresponds to the upper side of the working position of the nuclear instrument 3. The second position monitoring unit 5 is used to monitor the current position of the nuclear instrument 3 in real time. It is set on the side wall of the guide cylinder 1 and corresponds to the lower side of the working position of the nuclear instrument 3. The host computer 6 is communicatively connected to the first position monitoring unit 4 and the second position monitoring unit 5 to obtain the current position of the nuclear instrument 3 monitored by the first position monitoring unit 4 and the second position monitoring unit 5 in real time. In this way, when arranging the nuclear instrument 3, it is only necessary to move the nuclear instrument 3 downward along the installation channel 11 of the guide cylinder 1. When the lower side of the nuclear instrument 3 reaches the first position monitoring unit 5, the nuclear instrument 3 will be moved downward. When the position monitoring unit 4 reaches the elevation of the first position monitoring unit 4, the operator can immediately remotely obtain the current position of the nuclear instrument 3 monitored by the first position monitoring unit 4. When the lower side of the nuclear instrument 3 reaches the elevation of the second position monitoring unit 5, the operator can immediately remotely obtain the current position of the nuclear instrument 3 monitored by the second position monitoring unit 5. At this time, the nuclear instrument 3 reaches the working position, and the arrangement of the nuclear instrument 3 is completed. The position information of the nuclear instrument 3 can be obtained more timely and accurately without relying on theoretical calculations and manual experience. The entire process of nuclear instrument 3 arrangement is informatized, which meets the installation accuracy requirements of the nuclear instrument 3, improves the arrangement efficiency, and avoids the installation personnel going to the detector arrangement site with poor environmental conditions and high radiation dose, thus reducing the radiation risk.

[0025] Please refer to Figures 1 to 3. In one embodiment of the present invention, the first position monitoring unit 4 can be a position switch. The principle of the position switch is that it is an inductive switch that can measure distance without direct mechanical contact with the object being detected. When the nuclear instrument 3 enters the response action distance range of the position switch, the position switch can switch to change, thereby providing control commands to the host computer 6. It is small in size, flexible in installation, highly reliable, has strong anti-interference ability and long service life.

[0026] Please refer to Figures 1 to 3. In one embodiment of the present invention, the position switch may include at least one inductive position switch 41 and at least one mechanical position switch 42. The inductive position switch 41 and the mechanical position switch 42 are arranged circumferentially along the side wall of the guide cylinder 1. This use of two different position switches can avoid monitoring failure due to common faults. The two switches are redundant to each other, which improves the reliability of the monitoring system. The inductive position switch 41 does not need to make mechanical contact with the nuclear instrument 3, avoiding wear that could cause position switch failure. The mechanical position switch 42 has no electronic components, has strong radiation resistance, and avoids reduced working life due to strong radiation. Both the inductive position switch 41 and the mechanical position switch 42 can adopt conventional designs in this field. The principle of the inductive position switch 41 is as follows: when the nuclear instrument 3 approaches the magnetic field range emitted by the inductive position switch 41, the metal surface of the nuclear instrument 3 forms eddy currents under the action of electromagnetic induction, and reacts on the receiving surface of the inductive position switch 41, thereby causing the inductance value of the receiving coil to change, thus realizing the switching action. It has a fast response speed, long service life, can convert the position information of the detected object into an electrical signal, is more adaptable to harsh measurement environments, and has a sensing distance of 0.1mm~1mm, which meets the installation accuracy of ±10mm for the nuclear instrument.

[0027] In one embodiment of the present invention, the mechanical position switch 42 can be a rolling mechanical position switch. The principle of the rolling mechanical position switch is as follows: when the nuclear instrument 3 presses onto the roller of the rolling mechanical position switch at a certain angle, the state of the internal contacts of the switch is changed. When the nuclear instrument 3 leaves the roller, the return spring resets the limit switch, thereby realizing the switching change, and thus monitoring the current position of the nuclear instrument 3 in real time. It has strong radiation resistance and the accuracy of the rolling position switch can reach 0.01mm~0.1mm, which meets the installation accuracy of ±10mm for the nuclear instrument.

[0028] It is conceivable that the selection of position switches includes, but is not limited to, inductive position switches 41 and mechanical position switches 42. For example, ultrasonic position switches, photoelectric position switches, etc., can also be used. Furthermore, in other embodiments of the present invention, the position switch may also use only one inductive position switch 41 or only one mechanical position switch 42, but the effect is slightly inferior to the above embodiments.

[0029] Please refer to Figures 1 to 3. In one embodiment of the present invention, the number of both inductive position switches 41 and mechanical position switches 42 can be two. The two inductive position switches 41 and the two mechanical position switches 42 are arranged symmetrically. By using two symmetrically arranged inductive position switches 41 and two rolling mechanical position switches, dual non-contact and dual contact position signals can be obtained within the same movement stroke. Even if any one signal fails, the position of the nuclear instrument 3 can still be accurately monitored.

[0030] Please refer to Figures 1 to 3. In one embodiment of the present invention, the second position monitoring unit 5 preferably has the same structure as the first position monitoring unit 4. That is, the second position monitoring unit 5 also includes at least one inductive position switch 51 and at least one mechanical position switch 52. In this way, only the same model of spare parts is needed, which significantly reduces inventory costs. At the same time, during on-site installation, there is no need to distinguish between the first position monitoring unit 4 and the second position monitoring unit 5, which reduces installation errors, shortens installation time, and further improves monitoring accuracy and reliability.

[0031] Please refer to Figures 1 to 3. In one embodiment of the present invention, the position monitoring system may further include a display 7. The display 7 is communicatively connected to the host computer 6 and is used to display the current position of the nuclear instrument 3 in real time. In this way, the real-time position of the nuclear instrument 3 can be presented intuitively in a graphical manner through the display 7, realizing visualization. During the arrangement of the nuclear instrument 3, the operator can intuitively obtain information feedback on the installation progress and whether the nuclear instrument 3 is installed in place through the display 7 screen. For example, when the nuclear instrument 3 is descending along the guide tube 1, if the lower side of the nuclear instrument 3 has not reached the position of the first position monitoring unit 4, the screen shows the nuclear instrument 3 in the process of descending. When the lower side of the nuclear instrument 3 reaches the position of the first position monitoring unit 4, the screen shows that the nuclear instrument 3 has reached the first position monitoring unit 4, that is, reached the working position. When the lower side of the nuclear instrument 3 reaches the position of the second position monitoring unit 5, the screen shows that the nuclear instrument 3 has reached the designated working position. This makes it convenient for the operator to understand the arrangement status of the nuclear instrument 3 in real time, promptly detect and deal with possible abnormal situations, meet the installation accuracy requirements of the nuclear instrument 3, improve the arrangement efficiency, and reduce the radiation risk.

[0032] Please refer to Figures 1 to 3. In one embodiment of the present invention, the side wall of the guide cylinder 1 may be provided with a groove 12 extending along the length direction. A cable 8 is threaded through the groove 12. The first position monitoring unit 4 and the second position monitoring unit 5 are both connected to the host computer 6 via the cable 8. In this way, by setting the groove 12 along the length direction on the side wall of the guide cylinder 1 and housing the cable 8 therein, the signal lines of the first position monitoring unit 4 and the second position monitoring unit 5 are protected by the cylinder wall throughout the entire process, avoiding scratching with the nuclear instrument 3 during the movement, reducing the risk of signal attenuation and electromagnetic interference, and improving communication stability.

[0033] Please refer to Figures 1 to 3. In one embodiment of the present invention, the host computer 6 may include a digital signal processing cabinet 61. The digital signal processing cabinet 61 is communicatively connected to the first position monitoring unit 4 and the second position monitoring unit 5. In this way, the host computer 6 is integrated in the form of a digital signal processing cabinet 61, which can centrally access, uniformly regulate and process the signals of the first position monitoring unit 4 and the second position monitoring unit 5, so as to ensure the signal integrity and measurement consistency under long-distance transmission.

[0034] In summary, during the arrangement of nuclear instrument 3, when nuclear instrument 3 moves to the predetermined working position through the installation channel 11 of the guide tube 1, the first position monitoring unit 4 and the second position monitoring unit 5 will respectively detect the current position of nuclear instrument 3. The inductive position switch 41 generates an electrical signal by sensing the metal part of nuclear instrument 3, and the rolling mechanical position switch changes the switching state through physical contact with nuclear instrument 3. These signals are transmitted to the digital signal processing cabinet 61 of the host computer 6 through the cable 8 in the cable tray 12. The digital signal processing cabinet 61 processes and analyzes the received signals to determine the precise position of nuclear instrument 3 and displays the position information on the display 7 in real time, so that the operators can clearly understand the working status of nuclear instrument 3. This ensures the accuracy and reliability of the position monitoring of nuclear instrument 3 in the nuclear power plant, effectively avoids measurement errors or safety hazards caused by the position deviation of nuclear instrument 3, and is of great significance to ensuring the safe operation of the nuclear power plant.

[0035] This invention also provides a method for arranging nuclear instruments 3 using the aforementioned position monitoring system. The structure of the position monitoring system is the same as described above and will not be repeated here. The arrangement method includes: first, marking the upper and lower sides of the working position of the nuclear instrument 3 on the side wall of the guide cylinder 1; then, arranging the first position monitoring unit 4 on the upper side of the working position of the nuclear instrument 3, the specific arrangement method including but not limited to welding, bonding, riveting, pre-embedding, etc.; next, arranging the second position monitoring unit 5 on the lower side of the working position of the nuclear instrument 3, the specific arrangement method including but not limited to welding, bonding, riveting, pre-embedding, etc.; then pre-embedding the guide cylinder 1 around the reactor pressure vessel 2; then, moving the nuclear instrument 3 downward along the installation channel 11 of the guide cylinder 1, specifically by using a hoist. The device moves the nuclear instrument 3 downward along the installation channel 11 of the guide cylinder 1 using a steel wire rope 9. The lifting device includes, but is not limited to, a crane or tower crane. When the lower side of the nuclear instrument 3 reaches the elevation of the first position monitoring unit 4, the host computer 6 obtains the current position of the nuclear instrument 3 monitored by the first position monitoring unit 4. Then, the nuclear instrument 3 continues to be moved downward along the installation channel 11 of the guide cylinder 1. When the lower side of the nuclear instrument 3 reaches the elevation of the second position monitoring unit 5, the host computer 6 obtains the current position of the nuclear instrument 3 monitored by the second position monitoring unit 5. At this time, the nuclear instrument 3 reaches the working position, and the arrangement of the nuclear instrument 3 is completed.

[0036] In summary, the position monitoring system and arrangement method for nuclear instruments in nuclear power plants of the present invention, through a first position monitoring unit, a second position monitoring unit, a host computer, and a display, can obtain the current installation position of nuclear instruments in real time, providing rich position information for operation and maintenance personnel to guide the installation and maintenance of nuclear instruments. It can accurately control the installation position of nuclear instruments, avoid measurement errors or safety hazards caused by position deviations, improve the reliability of position monitoring, ensure that nuclear instruments can be accurately installed in the predetermined working position, and use mechanized hoisting tools throughout the process, reducing the workload of installation personnel. It has a simple structure, reliable performance, long service life, and strong radiation resistance, realizing intelligent, information-based, and visual installation process, which is of great significance for ensuring the safe operation of nuclear power plants.

[0037] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A position monitoring system for nuclear instruments in a nuclear power plant, characterized in that, include: A guide cylinder (1) is used to be embedded around the reactor pressure vessel (2), and an installation channel (11) is provided inside the guide cylinder (1) for the nuclear instrument (3) to pass through; a first position monitoring unit (4) is used to monitor the current position of the nuclear instrument (3) in real time, and is set on the side wall of the guide cylinder (1) and above the working position of the nuclear instrument (3); a second position monitoring unit (5) is used to monitor the current position of the nuclear instrument (3) in real time, and is set on the side wall of the guide cylinder (1) and below the working position of the nuclear instrument (3); a host computer (6) is used to communicate with the first position monitoring unit (4) and the second position monitoring unit (5) and to obtain the current position of the nuclear instrument (3) monitored by the first position monitoring unit (4) and the second position monitoring unit (5) in real time.

2. The position monitoring system for nuclear instruments in a nuclear power plant according to claim 1, characterized in that, The first position monitoring unit (4) is a position switch.

3. The position monitoring system for nuclear instruments in a nuclear power plant according to claim 2, characterized in that, The position switch includes at least one inductive position switch (41) and at least one mechanical position switch (42), the inductive position switch (41) and the mechanical position switch (42) being circumferentially spaced along the side wall of the guide cylinder (1).

4. The position monitoring system for nuclear instruments in a nuclear power plant according to claim 3, characterized in that, The number of inductive position switches (41) and mechanical position switches (42) are both two, and the two inductive position switches (41) and the two mechanical position switches (42) are arranged symmetrically.

5. The position monitoring system for nuclear instruments in a nuclear power plant according to claim 1, characterized in that, The second position monitoring unit (5) has the same structure as the first position monitoring unit (4).

6. The position monitoring system for nuclear instruments in a nuclear power plant according to claim 1, characterized in that, The location monitoring system also includes a display (7), which is communicatively connected to the host computer (6) and is used to display the current location of the nuclear instrument (3) in real time.

7. The position monitoring system for nuclear instruments in a nuclear power plant according to claim 1, characterized in that, The guide cylinder (1) has a wire groove (12) extending along its length on its side wall. A cable is threaded through the wire groove (12). The first position monitoring unit (4) and the second position monitoring unit (5) are both connected to the host computer (6) via the cable.

8. The position monitoring system for nuclear instruments in a nuclear power plant according to claim 1, characterized in that, The host computer (6) includes a digital signal processing cabinet (61), which is communicatively connected to the first position monitoring unit (4) and the second position monitoring unit (5).

9. A method for arranging nuclear instruments using the position monitoring system described in any one of claims 1 to 8, characterized in that, include: Mark the upper and lower sides of the working position of the nuclear instrument (3) on the side wall of the guide cylinder (1); The first position monitoring unit (4) is arranged above the working position of the nuclear instrument (3); the second position monitoring unit (5) is arranged below the working position of the nuclear instrument (3); the guide cylinder (1) is pre-embedded around the reactor pressure vessel (2); the nuclear instrument (3) is moved downward along the installation channel (11) of the guide cylinder (1); when the lower side of the nuclear instrument (3) reaches the elevation of the first position monitoring unit (4), the host computer (6) obtains the current position of the nuclear instrument (3) monitored by the first position monitoring unit (4); the nuclear instrument (3) is moved downward along the installation channel (11) of the guide cylinder (1); when the lower side of the nuclear instrument (3) reaches the elevation of the second position monitoring unit (5), the host computer (6) obtains the current position of the nuclear instrument (3) monitored by the second position monitoring unit (5); at this time, the nuclear instrument (3) reaches the working position, and the arrangement of the nuclear instrument (3) is completed.

10. The arrangement method according to claim 9, characterized in that, The nuclear instrument (3) is moved downward along the installation channel (11) of the guide cylinder (1) using a lifting device and a steel wire rope.

Images