Flexible shielding plate and radiation shielding structure of vertical heat exchanger

Abstract

The application relates to the technical field of equipment radiation shielding, in particular to a flexible shielding plate and a radiation shielding structure of a vertical heat exchanger, wherein the flexible shielding plate is formed by interlacing and weaving of multiple metal wires and has a bendable characteristic; the metal wires comprise a radiation-proof inner core and a reinforcing layer; the reinforcing layer covers and wraps the outer peripheral wall of the radiation-proof inner core; the reinforcing layer is a threaded sleeve structure formed by winding of a single high-strength wire or a mesh tube structure formed by interlacing and weaving of multiple high-strength wires; and the diameter of the radiation-proof inner core is 10-20 times that of the high-strength wire. The flexible shielding plate of the application is entirely composed of large-atomic-number and high-density metal after fiberization and then mixed weaving; the softened metal material can be moderately compressed, so that the flexible shielding plate can be applied to the surface of the vertical heat exchanger and a certain binding force is applied, thereby obtaining a larger friction force and preventing relative movement with the peripheral wall of the equipment, and meanwhile, the anti-seismic requirement design of the equipment is ensured, and the installation and dismounting are convenient.

Description

Technical Field

[0001] This application relates to the field of equipment radiation protection technology, and in particular to a radiation shielding structure for a flexible shielding plate and a vertical heat exchanger. Background Technology

[0002] A typical structure for a nuclear power plant's standing heat exchanger is the REN heat exchanger, see [link to relevant documentation]. Figure 1 As shown, the internal pipe side contains primary loop sampling water, which therefore has high radioactivity, typically with an average surface dose rate of 15 mSv / h. However, with various fixed pipelines and equipment arranged on the ground below and around the REN heat exchanger, effective radiation shielding has always been a challenging issue for nuclear power plants.

[0003] Currently, there are two types of commonly used radiation shielding materials for equipment: One type is the industry's initial use of solid lead pre-formed shielding devices through casting or lamination, with an outer shell of stainless steel or packaging gel for shaping. This type of shielding structure is rigid. This rigid shielding material cannot form frictional force with the heat exchanger surface after being bound, and it does not require other fixing methods to adhere to the heat exchanger body. Furthermore, rigid bodies lack deformation during on-site installation or removal, requiring significant manpower and time for preparation, resulting in drawbacks such as prolonged installation and removal time and a heavy radiation dose burden on personnel. Another type involves processing lead, tungsten, or other metals into powder, then mixing them with low-density polymer rubber and plastic materials and rolling them into composite rubber sheets or shaped structural parts with a certain density and relative softness. The mixing ratio of metal powder to rubber and plastic materials is generally about 60%:40%. The contribution of polymer materials with low density and atomic number to the protection against high-energy gamma rays is extremely small, but it contributes significantly to the overall weight of the shielding product. This structure essentially limits the design of increasing the effective shielding thickness, which is not conducive to reducing the radiation level of the on-site environment. As a functional material, the increase in metal powder in the composite rubber sheet will increase the mass of the non-metallic polymer carrier, which in turn will further increase the weight of the protective product. When the composite rubber sheet composed of inorganic metal and polymer rubber and plastic materials is exposed to high-energy photon irradiation, the polymer material is prone to aging, cracking, or embrittlement, which may lead to metal precipitation, resulting in a decrease in protective performance and potential occupational health risks. Therefore, there is currently no technology to effectively separate composite rubber sheet radiation protection products when they reach the end of their service life, thus failing to meet the environmental protection requirements of minimizing waste in the nuclear industry and medical industry.

[0004] Regarding the aforementioned technologies, the inventors believe that the following defects exist: Currently, the most common shielding method in the nuclear power industry is to use off-site prefabricated fixed shielding bodies to protect vertical heat exchangers. In order to meet the seismic requirements of nuclear power systems and equipment, radiation protection devices are separate from the equipment and are generally integrated in structure, which is quite heavy (estimated at 10mmPb equivalent, the weight of lead-plastic composite shielding material is about 200kg). Therefore, special temporary hoisting equipment is required for installation, which makes the installation process of radiation protection devices time-consuming and requires a lot of personnel, facing greater industrial safety risks and personnel radiation dose burden. Utility Model Content

[0005] This application provides a flexible shielding plate and a radiation shielding structure for a vertical heat exchanger to improve the following technical problems: Currently, the most common shielding method in the nuclear power industry is to use prefabricated fixed shielding structures to protect vertical heat exchangers. This requires the use of specialized temporary hoists for installation, which makes the installation process of radiation protection devices time-consuming, requires a large number of personnel, and poses significant industrial safety risks.

[0006] In the first aspect, this application provides a flexible shielding plate, which adopts the following technical solution: A flexible shielding plate is made of multiple metal wires crisscrossed and woven together, and has bendable characteristics. The metal wires include a radiation-shielding inner core and a reinforcing layer. The reinforcing layer covers and wraps the outer peripheral wall of the radiation-shielding inner core. The reinforcing layer is a threaded sleeve structure made of a single high-strength wire or a mesh-like structure made of multiple high-strength wires crisscrossed and woven together. The diameter of the radiation-shielding inner core is 10-20 times the diameter of the high-strength wire.

[0007] In one feasible technical solution of this application, the radiation-proof inner core is a single-strand structure and is made of lead wire, molybdenum wire, tungsten wire, nickel wire or platinum wire.

[0008] In one feasible technical solution of this application, the diameter of the radiation-shielding inner core is between 0.1 and 5.0 mm.

[0009] In one feasible technical solution of this application, the high-strength wire is a stainless steel wire.

[0010] In one feasible technical solution of this application, the diameter of the high-strength wire is between 0.01 and 1.00 mm.

[0011] Secondly, this application provides a radiation shielding structure for a vertical heat exchanger, employing the following technical solution: A radiation shielding structure for a vertical heat exchanger includes a top cap, an upper middle ring, a lower middle ring, and a bottom ring made of the aforementioned flexible shielding plate. The vertical heat exchanger includes an exchanger body and an upper fixed support, a lower fixed support, a cooling water inlet pipe, a sampling water inlet pipe, a sampling water outlet pipe, and a cooling water outlet pipe disposed on the exchanger body. The top cap, the upper middle ring, the lower middle ring, and the bottom ring are bound and fixed to and completely cover the outer peripheral wall of the exchanger body.

[0012] In one feasible technical solution of this application, the top cap includes a top arc plate and a side peripheral plate, wherein the side peripheral plate is integrally formed and perpendicular to the bottom periphery of the top arc plate.

[0013] In one feasible technical solution of this application, the upper ring portion includes two first arc-shaped plates, and a first notch is provided at the top corner of the first arc-shaped plate. The two first notches cooperate with the bottom edge of the top cap portion to form a hole through which the upper fixed bracket passes.

[0014] In one feasible technical solution of this application, the lower ring portion includes two second arc-shaped plates, the second arc-shaped plates having a semi-circular structure.

[0015] In one feasible technical solution of this application, the bottom ring portion includes two third arc-shaped plates, and a second notch is provided at the top corner of the third arc-shaped plate. The two second notches cooperate with the bottom edge of the middle and lower ring portion to form a hole for the lower fixed bracket to pass through. One of the third arc-shaped plates is provided with a hole for the cooling water inlet pipe to pass through.

[0016] In summary, this application includes at least one of the following beneficial technical effects: The diameter of the radiation-shielding core is much larger than that of the high-strength yarn, which ensures that the radiation-shielding core accounts for a very large proportion of the flexible shielding plate after it is woven, thus ensuring that the flexible shielding plate has a good radiation protection effect. At the same time, the reinforcing layer formed by the high-strength yarn has a good protective and reinforcing effect on the radiation-shielding core, effectively preventing the radiation-shielding core from easily breaking during bending, weaving and use. The flexible shielding plate is made entirely of high atomic number and high density metals that are fiberized and then woven together. The softened metal material can be moderately compressed, so it can be applied to the surface of the vertical heat exchanger and a certain binding force can be applied. This results in greater friction and prevents relative movement with the outer wall of the equipment. It is stable and firm and will not fall due to gravity. At the same time, it ensures the seismic resistance design of the equipment and does not affect the safety of the equipment and system in the event of an earthquake. Multiple components can be prefabricated off-site for use on different parts of the vertical heat exchanger. Each component is lightweight (generally between 1 and 50 kg) and can be quickly installed on-site by manpower. Components made of flexible shielding panels can be applied, bundled, and locked onto the surface of the vertical heat exchanger. It has the advantages of requiring fewer installation and dismantling personnel, eliminating the need for hoisting equipment, and enabling rapid installation and dismantling in a short time. In particular, it brings great advantages to the collective dose optimization of installation personnel and greatly reduces industrial safety risks. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the vertical heat exchanger in the embodiments of this application.

[0019] Figure 2 This is a schematic diagram of the structure of the flexible shielding plate in the embodiments of this application.

[0020] Figure 3 This is a schematic diagram of the structure of the metal wire in the embodiments of this application.

[0021] Figure 4 This is a schematic diagram of the radiation shielding structure of the vertical heat exchanger in the embodiments of this application.

[0022] Explanation of reference numerals in the attached figures: 1. Top cap; 11. Top arc plate; 12. Side peripheral plate; 2. Upper middle ring; 21. First arc plate; 211. First notch; 3. Lower middle ring; 31. Second arc plate; 4. Bottom ring; 41. Third arc plate; 411. Second notch; 10. Heat exchanger body; 20. Upper fixed bracket; 30. Lower fixed bracket; 40. Cooling water inlet pipe; 50. Sampling water inlet pipe; 60. Sampling water outlet pipe; 70. Cooling water outlet pipe; 100. Metal wire; 1001. Radiation-proof inner core; 1002. High-strength thread. Detailed Implementation

[0023] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0024] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0025] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0026] 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0027] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0028] This application discloses a radiation shielding structure for a flexible shielding plate and a vertical heat exchanger. (Refer to...) Figures 2-3 The flexible shielding plate is made of multiple metal wires 100 crisscrossed and woven together, and has bendable characteristics. The metal wires 100 include a radiation-shielding inner core 1001 and a reinforcing layer. The reinforcing layer covers and wraps the outer peripheral wall of the radiation-shielding inner core 1001. The reinforcing layer is a threaded sleeve structure made of a single high-strength wire 1002 or a mesh-like structure made of multiple high-strength wires 1002 crisscrossed and woven together. The diameter of the radiation-shielding inner core 1001 is 10-20 times the diameter of the high-strength wire 1002.

[0029] The radiation shielding core 1001 is a single-strand structure made of lead wire, which can be replaced with molybdenum wire, tungsten wire, nickel wire or platinum wire. The diameter of the radiation shielding core 1001 is between 0.1 and 5.0 mm. The high-strength wire 1002 is made of stainless steel, and the diameter of the high-strength wire 1002 is between 0.01 and 1.00 mm.

[0030] The beneficial technical effects of the flexible shielding plate in this application embodiment are roughly as follows: The diameter of the radiation-shielding core 1001 is much larger than that of the high-strength yarn 1002, which ensures that the radiation-shielding core 1001 accounts for a very large proportion of the flexible shielding plate after it is woven, thus ensuring that the flexible shielding plate has a good radiation protection effect. At the same time, the reinforcing layer formed by the high-strength yarn 1002 has a good protective and reinforcing effect on the radiation-shielding core 1001, effectively preventing the radiation-shielding core 1001 from easily breaking during bending, weaving and use. The flexible shielding plate is made entirely of high atomic number and high density metals that are fiberized and then woven together. The softened metal material can be moderately compressed, so it can be applied to the surface of the vertical heat exchanger and a certain binding force can be applied to obtain greater friction. It will not move relative to the outer wall of the equipment, making it stable and firm and preventing it from falling due to gravity. At the same time, it ensures the seismic resistance design of the equipment, so that the safety of the equipment and system will not be affected in the event of an earthquake. It is also easy to install and disassemble.

[0031] This application also discloses a radiation shielding structure for a vertical heat exchanger. (Refer to...) Figure 1 , Figure 2 and Figure 4 The radiation shielding structure includes a top cap 1, an upper middle ring 2, a lower middle ring 3, and a bottom ring 4 made of the aforementioned flexible shielding plate. The vertical heat exchanger includes an exchanger body 10 and an upper fixed bracket 20, a lower fixed bracket 30, a cooling water inlet pipe 40, a sampling water inlet pipe 50, a sampling water outlet pipe 60, and a cooling water outlet pipe 70, all mounted on the exchanger body 10. The top cap 1, the upper middle ring 2, the lower middle ring 3, and the bottom ring 4 are bound together and fixed to and completely cover the outer periphery of the exchanger body 10.

[0032] To accommodate the special structure of the main body 10 of the exchanger, the top cap 1 includes a top arc plate 11 and a side peripheral plate 12. The side peripheral plate 12 is integrally formed and perpendicular to the bottom edge of the top arc plate 11. The upper middle ring 2 includes two first arc plates 21. The top corner of the first arc plate 21 is provided with a first notch 211. The two first notches 211 cooperate with the bottom edge of the top cap 1 to form a hole for the upper fixed bracket 20 to pass through. The lower middle ring 3 includes two second arc plates 31. The second arc plates 31 have a semi-circular structure. The bottom ring 4 includes two third arc plates 41. The top corner of the third arc plate 41 is provided with a second notch 411. The two second notches 411 cooperate with the bottom edge of the lower middle ring 3 to form a hole for the lower fixed bracket 30 to pass through. One of the third arc plates 41 is provided with a hole for the cooling water inlet pipe 40 to pass through.

[0033] Through practical comparison: Traditional integrated shielding devices are installed using hoisting equipment, requiring an on-site work team of about 10 people, taking 24 hours, and the collective dose is expected to be 150 mSv; using the radiation shielding structure of this application for installation, the on-site work team is about 5 people and no hoisting equipment is required, taking about 4 hours, and the collective dose is expected to be <15 mSv.

[0034] The beneficial technical effects of the radiation shielding structure of the vertical heat exchanger in this application embodiment are roughly as follows: The flexible shielding plate is made entirely of high atomic number and high density metals that are fiberized and then woven together. The softened metal material can be moderately compressed, so it can be applied to the surface of the vertical heat exchanger and a certain binding force can be applied. This results in greater friction and prevents relative movement with the outer wall of the equipment. It is stable and firm and will not fall due to gravity. At the same time, it ensures the seismic resistance design of the equipment and does not affect the safety of the equipment and system in the event of an earthquake. Multiple components can be prefabricated off-site for use on different parts of the vertical heat exchanger. Each component is lightweight (generally between 1 and 50 kg) and can be quickly installed on-site by manpower. Components made of flexible shielding panels can be applied, bundled, and locked onto the surface of the vertical heat exchanger. It has the advantages of requiring fewer installation and dismantling personnel, eliminating the need for hoisting equipment, and enabling rapid installation and dismantling in a short time. In particular, it brings great advantages to the collective dose optimization of installation personnel and greatly reduces industrial safety risks.

[0035] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A flexible shielding plate, characterized in that, It is made of multiple metal wires (100) interwoven and woven together and has bendable characteristics. The metal wires (100) include a radiation-proof inner core (1001) and a reinforcing layer. The reinforcing layer covers and wraps the outer peripheral wall of the radiation-proof inner core (1001). The reinforcing layer is a threaded sleeve structure made of a single high-strength wire (1002) or a mesh structure made of multiple high-strength wires (1002) interwoven together. The diameter of the radiation-proof inner core (1001) is 10-20 times the diameter of the high-strength wire (1002).

2. The flexible shielding plate according to claim 1, characterized in that, The radiation-proof inner core (1001) is a single-strand structure and is made of lead wire, tungsten wire, molybdenum wire, nickel wire or platinum wire.

3. The flexible shielding plate according to claim 2, characterized in that, The diameter of the radiation shielding core (1001) is between 0.1 and 5.0 mm.

4. The flexible shielding plate according to claim 1, characterized in that, The high-strength wire (1002) is stainless steel wire.

5. The flexible shielding plate according to claim 4, characterized in that, The diameter of the high-strength filament (1002) is between 0.01 and 1.00 mm.

6. A radiation shielding structure for a vertical heat exchanger, characterized in that, The vertical heat exchanger includes a top cap (1), an upper middle ring (2), a lower middle ring (3), and a bottom ring (4) made of a flexible shielding plate as described in any one of claims 1-5. The heat exchanger includes an exchanger body (10) and an upper fixed bracket (20), a lower fixed bracket (30), a cooling water inlet pipe (40), a sampling water inlet pipe (50), a sampling water outlet pipe (60), and a cooling water outlet pipe (70) disposed on the exchanger body (10). The top cap (1), the upper middle ring (2), the lower middle ring (3), and the bottom ring (4) are bound and fixed to and completely cover the outer peripheral wall of the exchanger body (10).

7. The radiation shielding structure of the vertical heat exchanger according to claim 6, characterized in that, The top cap (1) includes a top arc plate (11) and a side peripheral plate (12), the side peripheral plate (12) being integrally formed and perpendicular to the bottom periphery of the top arc plate (11).

8. The radiation shielding structure of the vertical heat exchanger according to claim 6, characterized in that, The upper ring portion (2) includes two first arc-shaped plates (21). The top corner of the first arc-shaped plate (21) is provided with a first notch (211). The two first notches (211) cooperate with the bottom edge of the top cap portion (1) to form a hole through which the upper fixed bracket (20) passes.

9. The radiation shielding structure of the vertical heat exchanger according to claim 6, characterized in that, The lower ring (3) includes two second arc-shaped plates (31), which are semi-circular in structure.

10. The radiation shielding structure of the vertical heat exchanger according to claim 6, characterized in that, The bottom ring (4) includes two third arc-shaped plates (41). The top corner of the third arc-shaped plate (41) is provided with a second notch (411). The two second notches (411) cooperate with the bottom edge of the middle and lower ring (3) to form a hole through which the lower fixed bracket (30) passes. One of the third arc-shaped plates (41) is provided with a hole through which the cooling water inlet pipe (40) passes.

Images