Calibration device and method for sectional type magnetic turning plate liquid level meter of water supply tank of nuclear power plant

Abstract

The invention discloses a nuclear power plant water supply tank sectional type magnetic turning plate liquid level meter verification device and method. The verification device comprises an auxiliary water supply tank, a sectional type magnetic turning plate liquid level meter, a first isolation valve assembly, a water supplementing pipeline, a second isolation valve assembly and a temporary liquid level meter. The sectional type magnetic turning plate liquid level meters are arranged on the side faces of the auxiliary water supply tank respectively and communicate with the auxiliary water supply tank. The first isolating valve assembly is arranged between the sectional type magnetic turning plate liquid level meter and the auxiliary water supply tank; the sectional type magnetic turning plate liquid level meter is communicated with the water replenishing pipeline; the second isolating valve assembly is arranged between the sectional type magnetic turning plate liquid level meter and the water replenishing pipeline; the temporary liquid level meter is communicated with the water supplementing pipeline, and the liquid level scale of the temporary liquid level meter corresponds to the liquid level scale of the sectional type magnetic turning plate liquid level meter. The auxiliary water supply tank does not need to be filled with water, the influence of water quality on the auxiliary water supply tank does not need to be considered, and test difficulty and cost are reduced.

Description

Technical Field

[0001] The present invention relates to the field of instrument detection, and particularly to a calibration device and method for a segmented magnetic flap level gauge of a feed water tank in a nuclear power plant. Background Art

[0002] The start-up and shutdown auxiliary feed water system (hereinafter referred to as the AAS system) belongs to a dual-unit shared system and mainly undertakes the following operating functions: decoupling the conventional island due to reasons such as unit refueling overhaul and temporary shutdown for maintenance, or when the start-up and shutdown feed water system (hereinafter referred to as the AAD system) is unavailable, during the period when the unit ascends from the residual heat removal (hereinafter referred to as RHR) operating condition to the double-phase intermediate shutdown condition of the steam generator to the hot standby condition, during the period when the unit descends from the hot standby condition to the double-phase intermediate shutdown condition of the steam generator under the RHR operating condition, and during the period when the unit maintains the hot shutdown condition for a long time, the AAS system can replace the AAD system to maintain the normal water level of the steam generator. The water quality of the AAS system is demineralized and deaerated water, which can be used as an emergency feed water system. Its auxiliary feed water tank adopts a two-unit shared configuration, and the effective volume is not less than 830 m 3 , and the total volume is 1126 m 3 , in order to ensure that the water in the tank is always in a good deaerated and demineralized state, the upper space of the tank is covered with nitrogen, and the absolute pressure of nitrogen is 0.11 MPa.a to 0.112 MPa.a. When the pressure in the tank is too high, it is discharged through a pressure relief valve, and the set value is 0.112 Mpa.a.

[0003] A total of 6 formal level gauges are installed in the auxiliary feed water tank. The normal liquid level range of the auxiliary feed water tank is: 12.4 m < H < 13.5 m, and the alarm value range is: high liquid level alarm value: H ≥ 13.5 m; low liquid level alarm value: H ≤ 12.4 m; low 2 liquid level alarm value: H ≤ 0.9 m. Among the 6 level gauges of the auxiliary feed water tank, 3 are remote display level gauges and 3 are magnetic flap level gauges. After the installation of the auxiliary feed water tank is completed, it is necessary to fill and drain the medium to calibrate whether the deviation of the level gauge setting value meets the requirements.

[0004] In the prior art, the method adopted for calibrating the liquid level setting value of the magnetic flap level gauge is as follows: A visible level gauge is connected in parallel to the positive and negative pressure sides of the remote display level gauge of the auxiliary feed water tank; before filling the auxiliary feed water tank with water, it is necessary to empty the internal medium of the auxiliary feed water tank, and assist in opening the exhaust valve at the top of the tank, and adjust the pressure reducing valve to the lowest pressure working point; perform filling and draining operations on the entire auxiliary feed water tank through the system make-up water pipeline and the drainage pipeline, and perform level gauge comparison and calibration at the liquid level setting points of 0.9 m, 4 m, 7.5 m, 12.4 m, and 13.5 m; if at the above liquid level setting points, the deviation of the level gauge exceeds the range requirements, it is necessary to readjust the level gauge multiple times and then perform filling and draining operations on the auxiliary water tank multiple times until the level comparison and calibration meet the requirements.

[0005] However, the prior art has the following problems:

[0006] First of all, the auxiliary water supply tank is made of carbon steel, and the inner wall is easy to rust. Therefore, when performing the level gauge comparison and calibration, there are two options for the water supply source: one is to prepare desalted and deoxygenated water through the system to replenish the auxiliary water supply tank, and the water tank needs to be filled with nitrogen. However, the preparation of deoxygenated water requires that all equipment in the system have the requirements for startup and remote control, and requires supporting systems, such as steam heating system, dosing system, compressed air supply system, desalted water supply system, power supply system and nitrogen supply system, etc., to meet the conditions. This is undoubtedly an increase in the difficulty of the test in the early stage of system commissioning. The second is to add drugs, such as hydrazine and ammonia water, to the auxiliary water supply tank. However, hydrazine is an explosive drug and ammonia water has a pungent odor. In addition, after the water tank is added with drugs, any drainage of the auxiliary water supply tank is controlled in accordance with the requirements for the discharge of dosing wastewater, that is, samples must be sent for testing, and unqualified ones need to be treated before they can be discharged, which will undoubtedly increase the difficulty and duration of the test.

[0007] Secondly, the auxiliary water supply tank needs to be filled and drained multiple times to compare and calibrate the magnetic flap level gauge and the remote level gauge, which increases the test water consumption by at least 2,000 cubic meters and also increases the test period by about 7 days, greatly increasing the test cost.

[0008] Thirdly, since the auxiliary water supply tank is made of carbon steel, it needs to be sealed and nitrogen-filled for maintenance. During the test filling and drainage, a large amount of nitrogen enters the auxiliary water supply tank. Once the water level is low, the internal nitrogen can easily leak out through other openings in the system, posing a risk of suffocation to the test personnel. Summary of the invention

[0009] In order to solve the problems in the prior art, the present invention provides a calibration device and a calibration method for a segmented magnetic flap level gauge of a feed water tank in a nuclear power plant.

[0010] In a first aspect, the present invention discloses a sectional magnetic flap level gauge calibration device for a feed water tank of a nuclear power plant, comprising:

[0011] Auxiliary water tank;

[0012] A segmented magnetic flap level gauge is respectively arranged on the side of the auxiliary water supply tank, and the segmented magnetic flap level gauge is connected to the auxiliary water supply tank;

[0013] A first isolation valve assembly is arranged between the segmented magnetic flap level gauge and the auxiliary water supply tank;

[0014] A water supply pipeline, the segmented magnetic flap level gauge is connected to the water supply pipeline;

[0015] A second isolation valve assembly is arranged between the segmented magnetic flap level gauge and the water supply pipeline;

[0016] A temporary liquid level gauge is connected to the water supply pipeline, and the liquid level scale of the temporary liquid level gauge corresponds to the liquid level scale of the segmented magnetic flap liquid level gauge.

[0017] In some embodiments, the verification device also includes a buffer tank and a first separating valve. The buffer tank is arranged on the water supply pipeline, and the buffer tank is arranged upstream of the segmented magnetic flap level gauge and the temporary level gauge. The first separating valve is arranged on the water supply pipeline upstream of the buffer tank.

[0018] In some embodiments, the calibration device further comprises a remote display liquid level gauge assembly, and a positive pressure side of the remote display liquid level gauge assembly is connected to the water replenishment pipeline.

[0019] In some embodiments, the calibration device further comprises a digital control system, which is electrically connected to the remote display liquid level gauge assembly and is used to display the reading of the remote display liquid level gauge assembly.

[0020] In some embodiments, the segmented magnetic flap level gauge is vertically arranged, and the temporary level gauge is arranged parallel to the segmented magnetic flap level gauge.

[0021] In some embodiments, the water replenishment pipeline is arranged below the segmented magnetic flap level gauge and the temporary level gauge.

[0022] In some embodiments, the verification device further includes a drainage pipeline and a second separation valve, the drainage pipeline is connected to the buffer tank, and the second separation valve is arranged on the drainage pipeline.

[0023] In some embodiments, the verification device further includes a third separating valve, and the third separating valve is arranged between the temporary liquid level gauge and the water supply pipeline; the top of the temporary liquid level gauge is arranged to face the air.

[0024] In some embodiments, the calibration device further includes a pressure relief valve assembly, and the pressure relief valve assembly is disposed on the top of the segmented magnetic flap level gauge.

[0025] In a second aspect, the present invention further discloses a calibration method for use in the calibration device for the segmented magnetic flap level gauge of a feed water tank in a nuclear power plant described in the first aspect. The calibration method comprises the following steps:

[0026] The pipeline and level gauge of the sectional magnetic flap level gauge calibration device of the feed water tank of the nuclear power plant are tested online;

[0027] Obtaining a liquid level change value of the auxiliary water supply tank during actual filling and drainage to confirm a predetermined liquid level, and obtaining a filling and drainage rate of the auxiliary water supply tank during actual filling and drainage;

[0028] According to the actual filling rate of the auxiliary water supply tank, adjusting the opening of the first separation valve to fill the calibration device with water;

[0029] When the liquid level of the temporary liquid level gauge reaches a predetermined liquid level, the water filling of the calibration device is stopped, and the water filling and exhaust of the remote display liquid level gauge assembly are performed;

[0030] Filling the calibration device with water again so that the liquid level of the temporary liquid level gauge reaches a predetermined liquid level;

[0031] Compare and verify the readings of the segmented magnetic flap level gauge and the remote display level gauge assembly with the reading of the temporary level gauge to determine whether they exceed a predetermined deviation range;

[0032] If it exceeds the predetermined deviation range, the segmented magnetic flap level gauge and the display level gauge assembly are adjusted until the readings of the segmented magnetic flap level gauge and the display level gauge assembly are within the predetermined deviation range.

[0033] Beneficial effects of the invention: The invention discloses a calibration device and a calibration method for a segmented magnetic flap level gauge of a nuclear power plant feed water tank, the calibration device comprising an auxiliary feed water tank, a segmented magnetic flap level gauge, a first isolation valve assembly, a water supply pipeline, a second isolation valve assembly and a temporary level gauge; the segmented magnetic flap level gauges are respectively arranged on the sides of the auxiliary feed water tank, and the segmented magnetic flap level gauge is connected to the auxiliary feed water tank; the first isolation valve assembly is arranged between the segmented magnetic flap level gauge and the auxiliary feed water tank; the segmented magnetic flap level gauge is connected to the water supply pipeline; the second isolation valve assembly is arranged between the segmented magnetic flap level gauge and the water supply pipeline; the temporary level gauge is connected to the water supply pipeline, and the liquid level scale of the temporary level gauge corresponds to the liquid level scale of the segmented magnetic flap level gauge. By setting a first isolating valve assembly between the segmented magnetic flap level gauge and the auxiliary water supply tank, and the water supply pipeline is connected to the segmented magnetic flap level gauge at the same time, and a temporary level gauge connected to the water supply pipeline is set, and the reading of the temporary level gauge is compared with the reading of the segmented magnetic flap level gauge, the segmented magnetic flap level gauge can be calibrated. When calibrating, the first isolating valve assembly is closed to block the liquid connection between the segmented magnetic flap level gauge and the auxiliary water supply tank, so that there is no need to fill water into the auxiliary water supply tank, and there is no need to consider the impact of water quality on the auxiliary water supply tank, so that there is no need to strictly require the water quality of the water supply source, thereby reducing the difficulty and cost of the test; and there is no need to carry out large-scale filling and drainage, thereby reducing time cost; there is no need to fill the auxiliary water supply tank with nitrogen during calibration, thereby improving the safety of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0035] Figure 1 A schematic diagram of the overall structure of a sectional magnetic flap level gauge calibration device for a nuclear power plant feed water tank provided by an embodiment of the present invention;

[0036] Figure 2 A schematic block diagram of a digital control system for a sectional magnetic flap level gauge calibration device for a feed water tank in a nuclear power plant provided by an embodiment of the present invention;

[0037] Figure 3 A step diagram of a verification method provided in an embodiment of the present invention.

[0038] Figure numbers: 10, auxiliary water tank; 11, segmented magnetic flap level gauge; 111, first magnetic flap level gauge; 112, second magnetic flap level gauge; 113, third magnetic flap level gauge; 12, temporary level gauge; 13, water supply pipeline; 14, first isolation valve assembly; 141, first isolation valve; 142, second isolation valve; 143, third isolation valve; 144, fourth isolation valve; 145, fifth isolation valve; 146, sixth isolation valve; 15, second isolation valve assembly; 151, seventh isolation valve; 152, eighth isolation valve; 153, The ninth isolating valve; 16. Buffer tank; 17. The first separating valve; 18. The second separating valve; 19. The third separating valve; 20. Remote display level gauge assembly; 201. The first remote display level gauge; 202. The second remote display level gauge; 203. The third remote display level gauge; 21. Digital control system; 211. Acquisition device; 212. Processing device; 213. Display device; 214. Storage device; 22. Pressure relief valve assembly; 221. The first pressure relief valve; 222. The second pressure relief valve; 223. The third pressure relief valve; 23. Drainage pipeline. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0041] It should also be noted that, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there may be one or more intermediate elements. The terms "first", "second", "third", etc. are only for the convenience of describing the present technical solution, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", "third", etc. can explicitly or implicitly include one or more of the features. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0042] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0043] It should be further understood that the terms "and, or" used in the present description and the appended claims refer to and include any and all possible combinations of one or more of the associated listed items.

[0044] like Figure 1 As shown, the embodiment of the present invention discloses a sectional magnetic flap level gauge calibration device for a nuclear power plant feed water tank, which is used to calibrate the magnetic flap level gauge provided on the auxiliary feed water tank 10 of the startup and shutdown auxiliary feed water system. The calibration device may include the auxiliary feed water tank 10, the sectional magnetic flap level gauge 11, the first isolation valve assembly 14, the water supply pipeline 13, the second isolation valve assembly 15 and the temporary level gauge 12. The auxiliary feed water tank 10 is made of carbon steel, and its effective volume is not less than 830m 3 , with a total volume of 1126m 3The segmented magnetic flap level gauge 11 is respectively arranged on the side of the auxiliary water supply tank 10, and the segmented magnetic flap level gauge 11 is connected with the auxiliary water supply tank 10, so that the liquid level in the measuring tube of the segmented magnetic flap level gauge 11 is consistent with the liquid level in the auxiliary water supply tank 10, so that it can be used to detect the liquid level in the auxiliary water supply tank 10 in real time. When the liquid level changes, the turning column of the magnetic flap level gauge changes from red to white or from white to red, and the scale value corresponding to the top red turning column is the real-time liquid level value, so that the staff can not only read the liquid level value of the auxiliary water supply tank 10 from the scale of the magnetic flap level gauge, but also timely understand the liquid level changes of the auxiliary water supply tank 10. The first isolation valve assembly 14 is arranged between the segmented magnetic flap level gauge 11 and the auxiliary water supply tank 10, and is used to control the liquid connection and disconnection between the segmented magnetic flap level and the auxiliary water supply tank 10. When the auxiliary water supply tank 10 is normally filled and drained, the first isolation valve assembly 14 is opened; when the segmented magnetic flap level gauge 11 is checked, the first isolation valve assembly 14 is closed. The segmented magnetic flap level gauge 11 is connected to the water supply pipeline 13, and the water supply pipeline 13 is connected to the water supply source. When the liquid level is checked, water can be filled into the segmented magnetic flap level gauge 11 at the same time. The second isolation valve assembly 15 is arranged between the segmented magnetic flap level gauge 11 and the water supply pipeline 13, and is used to control the liquid connection and disconnection between the segmented magnetic flap level gauge 11 and the water supply pipeline 13. When the auxiliary water supply tank 10 is normally filled and drained, the second isolation valve assembly 15 is closed; when the segmented magnetic flap level gauge 11 is checked, the first isolation valve assembly 14 is opened to allow the liquid in the water supply pipeline 13 to enter the segmented magnetic flap level gauge 11. The temporary level gauge 12 is connected to the water supply pipeline 13, and the liquid level scale of the temporary level gauge 12 corresponds to the liquid level scale of the segmented magnetic flap level gauge 11. A first isolating valve assembly 14 is arranged between the segmented magnetic flap level gauge 11 and the auxiliary water supply tank 10, and the water supply pipeline 13 is connected to the segmented magnetic flap level gauge 11 at the same time, and a temporary level gauge 12 connected to the water supply pipeline 13 is arranged, and the reading of the temporary level gauge 12 is compared with the reading of the segmented magnetic flap level gauge 11 to realize the calibration of the segmented magnetic flap level gauge 11. When performing the calibration, the first isolating valve assembly is closed to block the liquid connection between the segmented magnetic flap level gauge 11 and the auxiliary water supply tank 10, so that there is no need to fill water into the auxiliary water supply tank 10, and there is no need to consider the influence of water quality on the auxiliary water supply tank 10, so that there is no need to strictly require the water quality of the water supply source, thereby reducing the difficulty and cost of the test; and there is no need to carry out large-scale filling and drainage, thereby reducing the time cost; and there is no need to perform nitrogen filling operation on the auxiliary water supply tank 10 during the calibration, thereby improving the safety of the test.

[0045] In some embodiments, the segmented magnetic flap level gauge 11 is arranged vertically, and the temporary level gauge 12 is arranged parallel to the segmented magnetic flap level gauge 11, so that the scale of the temporary level gauge 12 is aligned with the scale of the segmented magnetic flap level gauge 11. The segmented magnetic flap level gauge 11 can be arranged parallel to the side wall of the auxiliary water supply tank 10, so that the segmented magnetic flap level gauge 11 is aligned with the scale of the auxiliary water supply tank 10.

[0046] Specifically, the segmented magnetic flap level gauge 11 may include a first magnetic flap level gauge 111, a second magnetic flap level gauge 112 and a third magnetic flap level gauge 113, so that the range of the segmented magnetic flap level gauge 11 can completely cover the elevation of the auxiliary water supply tank 10. Among them, the zero scale of the first magnetic flap level gauge 111 is aligned with the zero scale of the auxiliary water supply tank 10. From the perspective of the side of the auxiliary water supply tank 10, the first magnetic flap level gauge 111, the second magnetic flap level gauge 112 and the third magnetic flap level gauge 113 are staggered, that is, the first magnetic flap level gauge 111, the second magnetic flap level gauge 112 and the third magnetic flap level gauge 113 are not in the same straight line to avoid collision between them.

[0047] The first isolation valve assembly 14 may include a first isolation valve 141, a second isolation valve 142, a third isolation valve 143, a fourth isolation valve 144, a fifth isolation valve 145 and a sixth isolation valve 146. The first isolation valve 141 is arranged between the upper half of the first magnetic flap level gauge 111 and the auxiliary water supply tank 10, and the second isolation valve 142 is arranged between the lower half of the first magnetic flap level gauge 111 and the auxiliary water supply tank 10. The third isolation valve 143 is arranged between the upper half of the second magnetic flap level gauge 112 and the auxiliary water supply tank 10, and the fourth isolation valve 144 is arranged between the lower half of the second magnetic flap level gauge 112 and the auxiliary water supply tank 10. The fifth isolation valve 145 is arranged between the upper half of the third magnetic flap level gauge 113 and the auxiliary water supply tank 10, and the sixth isolation valve 146 is arranged between the lower half of the third magnetic flap level gauge 113 and the auxiliary water supply tank 10.

[0048] The second isolation valve assembly 15 may include a seventh isolation valve 151, an eighth isolation valve 152 and a ninth isolation valve 153. The seventh isolation valve 151 is arranged between the first magnetic flap level gauge 111 and the water supply pipeline 13, the eighth isolation valve 152 is arranged between the second magnetic flap level gauge 112 and the water supply pipeline 13, and the ninth isolation valve 153 is arranged between the third magnetic flap level gauge 113 and the water supply pipeline 13.

[0049] In some embodiments, the temporary liquid level gauge 12 may include a transparent hose and a qualified steel tape measure. One end of the hose is connected to the water supply pipeline 13, and the other end of the hose is fixed to the top of the auxiliary water supply tank 10. The top of the hose is connected to the external environment to balance the air pressure inside and outside the hose, improve the reading accuracy, and the entire hose is installed vertically; the steel tape measure is used as a scale tool for the temporary liquid level gauge 12 and is fixed on the hose, and its zero scale corresponds to the zero scale liquid level of the auxiliary water supply tank 10 and the zero scale liquid level of the first magnetic flap liquid level gauge 111.

[0050] It can be understood that in other embodiments, the temporary liquid level gauge 12 can also be a glass tube or a plastic tube with a scale on the side wall, and the bottom of the tube is connected to the water supply pipeline 13.

[0051] In some embodiments, the verification device also includes a buffer tank 16 and a first separating valve 17. The buffer tank 16 is arranged on the water supply pipeline 13, and the buffer tank 16 is arranged upstream of the segmented magnetic flap level gauge 11 and the temporary level gauge 12. The first separating valve 17 is arranged on the water supply pipeline 13 upstream of the buffer tank 16.

[0052] Specifically, the buffer tank 16 is used to perform liquid buffering on the segmented magnetic flap level gauge 11 and the temporary level gauge 12. The water first flows into the upstream buffer tank 16, and then enters the segmented magnetic flap level gauge 11 and the temporary level gauge 12 through the buffer tank 16, so that the liquid level rises steadily, reducing the liquid level fluctuation of the segmented magnetic flap level gauge 11 and the temporary level gauge 12 caused by water pressure, and avoiding droplets from splashing onto the wall of the level gauge, which facilitates reading and ensures more accurate reading. The first separation valve 17 can be used to control the switch of the water supply source, and the water flow rate in the water supply pipeline 13 can be adjusted by adjusting the opening of the first separation valve 17.

[0053] In some embodiments, the calibration device further comprises a remote display level gauge assembly 20, and the positive pressure side of the remote display level gauge assembly 20 is connected to the water supply pipeline 13. During the calibration process, the remote display level gauge assembly 20 can be used for comparison and calibration with the segmented magnetic flap level gauge 11.

[0054] Specifically, the remote display level gauge assembly 20 may include a first remote display level gauge 201, a second remote display level gauge 202, and a third remote display level gauge 203. The positive pressure sides of the first remote display level gauge 201, the second remote display level gauge 202, and the third remote display level gauge 203 are all connected to the water supply pipeline 13, and the negative pressure sides of the first remote display level gauge 201, the second remote display level gauge 202, and the third remote display level gauge 203 are connected to the top of the auxiliary feed water tank 10. During the verification process, the first remote display level gauge 201, the second remote display level gauge 202, and the third remote display level gauge 203 can be compared and verified with each other. When the auxiliary feed water tank 10 is normally filled and drained, the remote display level gauge assembly 20 can be used for nuclear power plant staff to remotely read the liquid level of the auxiliary feed water tank 10.

[0055] Read also Figure 2 In some embodiments, the calibration device further includes a digital control system 21 , which is electrically connected to the remote display liquid level gauge assembly 20 and is used to display the reading of the remote display liquid level gauge assembly 20 .

[0056] Specifically, the digital control system 21 may include a collection device 211, a processing device 212, a display device 213, and a storage device 214. The collection device 211 and the processing device 212 are used to collect and process the electrical signals of the first remote display level gauge 201, the second remote display level gauge 202, and the third remote display level gauge 203, respectively, convert the electrical signals into visible digital information, and display the digital information through the display device 213. The storage device 214 is used to store the scale data collected each time.

[0057] In some embodiments, the water replenishment pipeline 13 is arranged below the segmented magnetic flap level gauge 11 and the temporary level gauge 12 .

[0058] Specifically, the water supply pipeline 13 and the buffer tank 16 are both arranged below the segmented magnetic flap level gauge 11 and the temporary level gauge 12, so as to avoid the gravitational potential energy of the water flow caused by setting the water supply pipeline 13 at a high place affecting the readings of the segmented magnetic flap level gauge 11 and the temporary level gauge 12, thereby further improving the buffering performance of the buffer tank 16.

[0059] In some embodiments, the verification device further includes a drainage pipeline 23 and a second separation valve 18 . The drainage pipeline 23 is in communication with the buffer tank 16 , and the second separation valve 18 is disposed on the drainage pipeline 23 .

[0060] Specifically, the drainage pipeline 23 is arranged below the water supply pipeline 13, and the liquid in the water supply pipeline 13, the segmented magnetic flap liquid level gauge 11, the temporary liquid level gauge 12 and the remote display liquid level gauge assembly 20 can be discharged by opening the second separation valve 18. Thus, the verification device has a water filling verification process and a drainage verification process. When performing the water filling verification, the second separation valve 18 is closed; when performing the drainage verification, the second separation valve 18 is opened.

[0061] In some embodiments, the verification device further comprises a third separation valve 19, and the third separation valve 19 is arranged between the temporary liquid level gauge 12 and the water supply pipeline 13. The top of the temporary liquid level gauge 12 is arranged to face the air.

[0062] Specifically, the third separation valve 19 is arranged below the temporary liquid level gauge 12, and is used to control the liquid on and off between the temporary liquid level gauge 12 and the water supply pipeline 13. The top of the temporary liquid level gauge 12 is arranged to be open to air so that the internal and external air pressures of the temporary liquid level gauge 12 are balanced, thereby making the reading more accurate.

[0063] In some embodiments, the calibration device further includes a pressure relief valve assembly 22 , and the pressure relief valve assembly 22 is disposed on the top of the segmented magnetic flap level gauge 11 .

[0064] Specifically, the pressure relief valve assembly 22 includes a first pressure relief valve 221, a second pressure relief valve 222 and a third pressure relief valve 223. The first pressure relief valve 221 is arranged at the top of the first magnetic flap level gauge 111, the second pressure relief valve 222 is arranged at the top of the second magnetic flap level gauge 112, and the third pressure relief valve 223 is arranged at the top of the third magnetic flap level gauge 113. When performing a calibration, the first pressure relief valve 221, the second pressure relief valve 222 and the third pressure relief valve 223 are opened to balance the air pressure inside and outside the first magnetic flap level gauge 111, the second magnetic flap level gauge 112 and the third magnetic flap level gauge 113, keep the liquid level stable and improve the reading accuracy.

[0065] Read also Figure 3 The embodiment of the present invention further discloses a calibration method, which is applied to the calibration device of the segmented magnetic flap level gauge of the feed water tank of a nuclear power plant disclosed in the above embodiment, and includes steps S110 to S170:

[0066] S110, conducting online inspection on the pipeline and level gauge of the sectional magnetic flap level gauge calibration device for the feed water tank of the nuclear power plant.

[0067] Specifically, the first isolation valve assembly is closed, the second isolation valve assembly is opened, the pressure relief valve assembly is opened, the second separation valve is closed, and the third separation valve is opened.

[0068] S120, obtaining a liquid level change value of the auxiliary water supply tank during the actual filling and drainage period to confirm a predetermined liquid level, and obtaining a filling and drainage rate of the auxiliary water supply tank during the actual filling and drainage period.

[0069] Specifically, the predetermined liquid levels may include 0.9m, 4m, 7.5m, 12.4m and 13.5m, wherein 13.5m is a high liquid level alarm value, 12.4m is a low liquid level alarm value, and 0.9m is a low liquid level alarm value.

[0070] S130. According to the actual filling rate of the auxiliary water supply tank, adjust the opening of the first separating valve to fill the verification device with water.

[0071] Specifically, the first separating valve is opened, and according to the actual filling rate of the auxiliary water supply tank, the opening of the first separating valve is adjusted to fill the calibration device with water to ensure that the filling rate is the same as the actual filling rate of the auxiliary water supply tank.

[0072] S140. When the liquid level of the temporary liquid level gauge reaches a predetermined liquid level, stop filling the calibration device with water, and perform water filling and exhaust on the remote display liquid level gauge assembly.

[0073] Specifically, when multiple preset liquid levels are set, each time the liquid level of the temporary liquid level gauge reaches a preset liquid level, the first separating valve is closed, the water filling of the calibration device is stopped, and the remote display liquid level gauge assembly is filled with water and vented. At this time, the liquid level of each liquid level gauge will drop.

[0074] S150, filling the calibration device with water again so that the liquid level of the temporary liquid level gauge reaches a predetermined liquid level.

[0075] Specifically, the first separation valve is opened again at the same opening degree, so that the liquid level of the temporary liquid level gauge reaches a predetermined liquid level before the remote display liquid level gauge assembly is filled with water and exhausted.

[0076] S160. Compare and verify the readings of the segmented magnetic flap level gauge and the remote display level gauge assembly with the reading of the temporary level gauge to determine whether they exceed a predetermined deviation range.

[0077] Specifically, the first separation valve is closed and the readings of each level meter are read. The predetermined deviation range can be set to ±2 mm.

[0078] S170. If it exceeds the predetermined deviation range, the segmented magnetic flap level gauge and the display level gauge assembly are adjusted until the readings of the segmented magnetic flap level gauge and the display level gauge assembly are within the predetermined deviation range.

[0079] In this way, the calibration is performed in the order of liquid level from low to high, for example, in the order of 0.9m, 4m, 7.5m, 12.4m, and 13.5m.

[0080] A verification method disclosed in an embodiment of the present invention further includes the following steps after completing the water filling verification of all predetermined liquid levels:

[0081] The verification device is drained according to the actual drainage rate of the auxiliary water tank.

[0082] Specifically, the first separating valve is closed, the second separating valve is opened, and the opening of the second separating valve is adjusted according to the actual drainage rate of the auxiliary water supply tank to drain the calibration device to ensure that the filling rate is the same as the actual filling rate of the auxiliary water supply tank.

[0083] When the liquid levels of the temporary liquid level gauge and the segmented magnetic flap liquid level gauge reach the predetermined liquid level, the drainage is stopped, and the readings of the segmented magnetic flap liquid level gauge and the remote display liquid level gauge assembly are compared and verified with the reading of the temporary liquid level gauge to determine whether they exceed the predetermined deviation range; if they exceed the deviation range, the segmented magnetic flap liquid level gauge and the display liquid level gauge assembly are adjusted until the readings are within the predetermined deviation range.

[0084] In this way, the calibration is carried out in the order of liquid level from high to low, for example, the order of 13.5m, 12.4m, 7.5m, 4m, and 0.9m, so that the steps of filling calibration and drainage calibration are carried out for each predetermined liquid level, further improving the accuracy of the calibration.

[0085] The nuclear power plant feed water tank segmented magnetic flap level gauge calibration device and calibration method disclosed in the embodiment of the present invention have at least the following beneficial effects:

[0086] Effectively reduce the difficulty, cost and risk of verification and improve verification efficiency;

[0087] It can connect multiple magnetic flap level gauges and perform comparison and calibration with temporary level gauges and multiple remote level gauges at the same time to ensure high calibration accuracy and reliability;

[0088] The verification method has no requirements on the test water quality and is particularly suitable for the comparison and verification of magnetic flap level gauges in auxiliary feed water tanks of nuclear power plants.

[0089] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A sectional magnetic flap level gauge calibration device for a nuclear power plant feed water tank, characterized in that: include: Auxiliary water tank; A segmented magnetic flap level gauge is respectively arranged on the side of the auxiliary water supply tank, and the segmented magnetic flap level gauge is connected to the auxiliary water supply tank; A first isolation valve assembly is arranged between the segmented magnetic flap level gauge and the auxiliary water supply tank; A water supply pipeline, the segmented magnetic flap level gauge is connected to the water supply pipeline; A second isolation valve assembly is arranged between the segmented magnetic flap level gauge and the water supply pipeline; A temporary liquid level gauge is connected to the water supply pipeline, and the liquid level scale of the temporary liquid level gauge corresponds to the liquid level scale of the segmented magnetic flap liquid level gauge.

2. The sectional magnetic flap level gauge calibration device for a nuclear power plant feed water tank according to claim 1 is characterized in that: The verification device also includes a buffer box and a first separating valve. The buffer box is arranged on the water supply pipeline, and the buffer box is arranged upstream of the segmented magnetic flap level gauge and the temporary level gauge. The first separating valve is arranged on the water supply pipeline upstream of the buffer box.

3. The sectional magnetic flap level gauge calibration device for a feed water tank in a nuclear power plant according to claim 2 is characterized in that: The calibration device also includes a remote display liquid level gauge assembly, and the positive pressure side of the remote display liquid level gauge assembly is connected to the water replenishment pipeline.

4. The sectional magnetic flap level gauge calibration device for a nuclear power plant feed water tank according to claim 3 is characterized in that: The calibration device further comprises a digital control system, which is electrically connected to the remote display liquid level gauge assembly and is used to display the reading of the remote display liquid level gauge assembly.

5. The sectional magnetic flap level gauge calibration device for a nuclear power plant feed water tank according to any one of claims 3 to 4, characterized in that: The segmented magnetic flap level gauge is vertically arranged, and the temporary level gauge is arranged in parallel with the segmented magnetic flap level gauge.

6. The sectional magnetic flap level gauge calibration device for a feed water tank in a nuclear power plant according to any one of claims 3 to 4, characterized in that: The water replenishment pipeline is arranged below the segmented magnetic flap level gauge and the temporary level gauge.

7. The sectional magnetic flap level gauge calibration device for a feed water tank in a nuclear power plant according to any one of claims 3 to 4, characterized in that: The verification device further includes a drainage pipeline and a second separation valve. The drainage pipeline is communicated with the buffer tank, and the second separation valve is arranged on the drainage pipeline.

8. The sectional magnetic flap level gauge calibration device for a nuclear power plant feed water tank according to any one of claims 3 to 4, characterized in that: The verification device also includes a third separating valve, which is arranged between the temporary liquid level gauge and the water supply pipeline; the top of the temporary liquid level gauge is arranged to face the air.

9. The sectional magnetic flap level gauge calibration device for a feed water tank in a nuclear power plant according to any one of claims 3 to 4, characterized in that: The calibration device also includes a pressure relief valve assembly, which is arranged on the top of the segmented magnetic flap level gauge.

10. A calibration method, applied to the calibration device for the segmented magnetic flap level gauge of a feed water tank in a nuclear power plant according to any one of claims 3 to 9, characterized in that: The verification method comprises the steps of: The pipeline and level gauge of the sectional magnetic flap level gauge calibration device of the feed water tank of the nuclear power plant are tested online; Obtaining a liquid level change value of the auxiliary water supply tank during actual filling and drainage to confirm a predetermined liquid level, and obtaining a filling and drainage rate of the auxiliary water supply tank during actual filling and drainage; According to the actual filling rate of the auxiliary water supply tank, adjusting the opening of the first separation valve to fill the calibration device with water; When the liquid level of the temporary liquid level gauge reaches a predetermined liquid level, the water filling of the calibration device is stopped, and the water filling and exhaust of the remote display liquid level gauge assembly are performed; Filling the calibration device with water again so that the liquid level of the temporary liquid level gauge reaches a predetermined liquid level; Compare and verify the readings of the segmented magnetic flap level gauge and the remote display level gauge assembly with the reading of the temporary level gauge to determine whether they exceed a predetermined deviation range; If it exceeds the predetermined deviation range, the segmented magnetic flap level gauge and the display level gauge assembly are adjusted until the readings of the segmented magnetic flap level gauge and the display level gauge assembly are within the predetermined deviation range.

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