Automatic water replenishing device for single-cavity liquid level meter of nuclear power plant
By adding three-way devices and new instrument pipelines to the level meter system of the nuclear power plant, combined with the automatic water replenishment function of the first-level water supply pump of the energy station, the evaporation problem of the level meter during debugging and starting and stopping is solved, achieving efficient and accurate Automatic hydration improves work efficiency and measurement accuracy.
Patent Information
- Application Number
- CN202411519717.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-29
- Publication Date
- 2025-02-18
AI Technical Summary
During the debugging and start-stop, the media on the positive pressure side evaporates due to micro-negative pressure and other reasons, which affects the accuracy of liquid level measurement. It lacks water replenishment pipelines and interfaces, making it impossible to realize automatic water replenishment during load operation.
Design a single-cavity level meter automatic water replenishment device for nuclear power plants. By adding tee devices and new instrument pipelines to the instrument pipeline between the balance container tank and the transmitter, automatic water replenishment is achieved, and the first-level water supply pump of the energy station is used. Perform automatic and continuous hydration operations.
Automatic water replenishment of the evaporator and deaerator level gauge balance container tank is achieved, which improves measurement accuracy, reduces safety industrial risks, improves work efficiency, avoids air entering the balance container tank, and reduces the risk of human error. .
Smart Images
Figure CN119468070A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of instrumentation and control measurement, and in particular relates to an automatic water replenishing device for a single-cavity liquid level gauge in a nuclear power plant. Background Art
[0002] As the first nuclear energy steam supply project for industrial use in China, the Tianwan Nuclear Power Steam Supply Project uses the main steam of Units 3 and 4 as the heat source. After the steam is converted in the steam conversion equipment system, it is transported to the Lianyungang Petrochemical Industrial Base for industrial production. The main function of the energy station evaporator and superheater system is to use the heat of the main steam in the evaporator to heat and evaporate the industrial feed water, realize heat exchange, and produce industrial steam that meets the user's required parameters. The function of the deaerator is to heat the feed water and remove the oxygen and other non-condensable gases contained in the feed water, and store enough water to buffer when the evaporator feed water demand does not match the deaerator feed water inlet for a short time.
[0003] At present, the evaporator tube-side level gauge, shell-side level gauge and deaerator level gauge of the energy station are all designed as differential pressure type. During the commissioning and start-up and shutdown of the nuclear power plant energy station, in order to prevent the water in the positive pressure side balance container tank and instrument pipeline of the level gauge from evaporating due to slight negative pressure and other reasons, it is necessary to replenish water to the positive pressure side balance container tank and instrument pipeline of the level gauge in time to ensure that the important parameters related to the protection and control of various instruments in the energy station can be displayed normally. These instruments are used to monitor the evaporator tube side and shell side liquid level and deaerator liquid level, etc. However, the current instrument pressure pipeline is not designed with a water replenishment pipeline and a water replenishment interface, and it is impossible to realize the water replenishment operation during load operation; during the shutdown period, water can only be poured from the positive pressure side condenser tank plug, and there are problems such as the sealing plug is not restored strictly and the bubbles in the instrument tube cannot be removed.
[0004] The present invention proposes an automatic water replenishment method for a single-chamber liquid level gauge in a nuclear power plant to reduce the impact of the current design on instrument measurement. On the one hand, a water replenishment pipeline and a water replenishment interface are added by adding a three-way device to the instrument pipeline from the balancing container tank to the transmitter; on the other hand, the present invention uses the primary water supply pump of the energy station for automatic and continuous water replenishment. Therefore, the present invention does not require manual operation, greatly improves work efficiency, avoids air from entering the balancing container tank, and makes the measured instrument liquid level more accurate. Summary of the invention
[0005] The purpose of the present invention is to provide a simple and practical automatic water replenishing device for a single-chamber liquid level gauge in a nuclear power plant, which can realize the automatic water replenishing function of the energy station evaporator and deaerator liquid level gauge balance container tank, avoid the influence of evaporation of the positive pressure side medium in the balance container tank caused by slight negative pressure and the like on the liquid level measurement, improve the measurement accuracy, and at the same time, the automatic water replenishing method does not require manual operation, which greatly improves the work efficiency.
[0006] In order to achieve the above object, the technical solution adopted by the present invention is:
[0007] A single-chamber liquid level gauge automatic water replenishment device for a nuclear power plant comprises a DN50 pipeline, a manual stop valve A, a manual stop valve B, a manual stop valve C, a manual stop valve D, a manual stop valve E, a manual stop valve F, a manual stop valve G, a tee A, a tee B, a tee C and a newly added instrument pipeline; the DN50 pipeline is connected with a primary feedwater pump, the DN50 pipeline is provided with a manual stop valve A, the manual stop valve A is connected with the manual stop valve B and the manual stop valve C in sequence, the tee A is respectively connected with the manual stop valve C, a balancing container tank A and a tube-side liquid level gauge of an evaporator; the manual stop valve A is connected with the manual stop valve D and the manual stop valve E in sequence, the tee B is respectively connected with the manual stop valve E, the balancing container tank B and the shell-side liquid level gauge of the evaporator; the manual stop valve A is connected with the manual stop valve F and the manual stop valve G in sequence through the newly added instrument pipeline, and the tee C is respectively connected with the manual stop valve G, the balancing container tank C and the original instrument pipeline.
[0008] The primary water supply tank is connected to the primary water supply pump.
[0009] The original instrument pipeline is connected to the deaerator level gauge.
[0010] The primary feed water pump delivers the feed water to the subsequent system.
[0011] All manual stop valves are closed during normal operation and opened when replenishing water.
[0012] The new instrument pipeline material is carbon steel.
[0013] The beneficial effects achieved by the present invention are:
[0014] The present invention makes accurate measurement of the differential pressure liquid level of the evaporator tube side, shell side and deaerator by water replenishment, thereby reducing safety and industrial risks. The present invention uses the equipment of the steam conversion system in the energy station for operation, does not require additional important equipment, and has low cost. The pump of the present invention can automatically and continuously output water to the water replenishment port, does not require manual operation, and greatly improves work efficiency. During the water replenishment process of the present invention, the pump can continuously and uninterruptedly replenish water, avoiding air from entering the balancing container tank, making the instrument more accurate in measuring the liquid level. The present invention replenishes water in an automatic manner, reducing the number of isolation times before opening and closing the valve during manual water replenishment, and reducing the risk of human error. The quality of the water source of the present invention is controllable, and the water is taken from the water in the primary water supply tank, which reduces the time for personnel to fetch water from various places. The present invention moves the water replenishment port from the top of the balancing tank to a position where personnel can operate by adding a tee and an instrument pipeline, thereby reducing the time for high-altitude operations and scaffolding. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1This is a flow chart of an automatic water replenishment device for a single-chamber liquid level gauge in a nuclear power plant;
[0016] In the figure: 1-primary water supply tank; 2-primary water supply pump; 3-DN50 pipeline; 4-manual stop valve A; 5-manual stop valve B; 6-manual stop valve C; 7-balance container tank A; 8-tee A; 9-evaporator tube side liquid level gauge; 10-manual stop valve D; 11-manual stop valve E; 12-balance container tank B; 13-tee B; 14-evaporator shell side liquid level gauge; 15-manual stop valve F; 16-manual stop valve G; 17-balance container tank C; 18-tee C; 19-deaerator liquid level gauge; 20-original instrument pipeline; 21-newly added instrument pipeline. DETAILED DESCRIPTION
[0017] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.
[0018] The present invention provides an automatic water replenishment device for a single-cavity liquid level gauge in a nuclear power plant. Since each evaporator in the energy station has 3 balancing containers on the tube side, 3 balancing containers on the shell side, and 3 balancing containers on the deaerator, there are four evaporators and one deaerator, so the total number of balancing containers that need to add water replenishment pipelines is 27. The structural diagram of the present invention only selects one interface each on the evaporator tube side, shell side, and deaerator for display, and the water replenishment methods of the other interfaces are the same.
[0019] The DN50 pipeline 3 is connected to the primary water supply pump 2. A manual stop valve A4 is provided on the DN50 pipeline 3. The manual stop valve A4 is connected to the manual stop valve B5 and the manual stop valve C6 in sequence. The tee A8 is respectively connected to the manual stop valve C6, the balancing container tank A7 and the evaporator tube side liquid level gauge 9; the manual stop valve A4 is connected to the manual stop valve D10 and the manual stop valve E11 in sequence. The tee B13 is respectively connected to the manual stop valve E11, the balancing container tank B12 and the evaporator shell side liquid level gauge 14; the manual stop valve A4 is connected to the manual stop valve F15 and the manual stop valve G16 in sequence through the newly added instrument pipeline 21. The tee C18 is respectively connected to the manual stop valve G16, the balancing container tank C17 and the original instrument pipeline 20.
[0020] In the entire water replenishment work, the first-level water supply tank 1, the first-level water supply pump 2, the balancing container tank A7, the balancing container tank B12, the balancing container tank C17, the evaporator tube side liquid level gauge 9, the evaporator shell side liquid level gauge 14, the deaerator liquid level gauge 19 and the original instrument pipeline 20 are the equipment provided by the steam conversion device; the DN50 pipeline 3, the manual stop valve A4, the manual stop valve B5, the manual stop valve C6, the manual stop valve D10, the manual stop valve E11, the manual stop valve F15, the manual stop valve G16, the tee A8, the tee B13, the tee C18 and the newly added instrument pipeline 21 are newly added devices. The output end of the first-level water supply tank 1 is connected to the input end of the first-level water supply pump 2. The output end of the first-level water supply pump 2 transports the water to the subsequent system on the one hand, and transports the water to each water supply pipeline through the DN50 pipe 3 on the other hand. A manual stop valve A4 is arranged on the DN50 pipe 3 to control the water supply output; the water supply is transported to the vicinity of the water supply branches of the balancing container tank A7, the balancing container tank B12, and the balancing container tank C17 through the newly added instrument pipeline 21. A manual stop valve is arranged at the terminal of each water supply branch, which is a manual stop valve (5 / 6, 10 / 11, 15 / 16) for controlling the water supply transported to each balancing container tank; Tees A8, B13 and C18 are added to the original instrument pipeline 20 below the balancing container tank A7, the balancing container tank B12 and the balancing container tank C17, respectively, for connecting to each water supply pipeline.
[0021] The primary water supply tank 1 and the primary water supply pump 2 are self-contained equipment for steam energy conversion, wherein the primary water supply tank 1 is used to provide water to the balancing container tank A7, the balancing container tank B12 and the balancing container tank C17 and the original instrument pipeline 20 for replenishment to ensure that the quality of the water source is controllable. A DN50 pipe 3 is arranged on the outlet pipe of the primary water supply pump 2, and a stop valve 4 is arranged near the interface. The DN50 pipe interface 3 is connected to the vicinity of the water supply pipeline of each balancing container tank, and is connected to each water supply port respectively. Two manual stop valves (5 / 6, 10 / 11, 15 / 16) are arranged in front of each interface. The manual stop valve (5 / 6, 10 / 11, 15 / 16) means that the primary water supply pump outlet header leads to the water supply interface, and a manual stop valve is arranged on the water supply main pipe. Multiple water supply branches are designed between the water supply main pipe and the instrument pipe on the positive pressure side of the liquid level gauge. The water supply branch pipe and the instrument pipe are designed to be connected by a tee. A manual stop valve is designed at the terminal of the water supply branch pipe. The stop valve is usually closed when the system is operating normally, and is opened when replenishing water. The main function of the primary water supply pump 2 is to automatically and continuously transport the water in the primary water supply tank 1 to each balancing container tank. Then, tee A8, tee B13 and tee C18 are added to the original instrument pipeline 20 respectively, connected to the water supply tank, and the water in the water supply tank is transported to the positive pressure side condenser tank and the instrument pipeline through the first-stage water supply pump.
[0022] An automatic water replenishment device for a single-chamber liquid level gauge in a nuclear power plant includes a primary feedwater tank, a primary feedwater pump, a stop valve connected to a water intake, a manual stop valve 1 connected in front of the water replenishment port, a manual stop valve 2, an instrument pipe, and an instrument tee. The primary feedwater tank and the primary feedwater pump are steam energy conversion equipment, wherein the primary feedwater tank is used to provide a water source to replenish the balancing container tank to ensure that the quality of the water source is controllable. The primary feedwater pump is used to transport the water in the primary feedwater tank to the balancing container tank, which can be done automatically and continuously. A DN50 interface is provided on the outlet pipe of the primary feedwater pump, and a manual stop valve is provided near the interface. The DN50 pipeline is connected to the vicinity of the water replenishment pipeline of each balancing container tank and is connected to each water replenishment port respectively. Two manual stop valves are provided in front of the interface. The stop valve is usually closed when the system is operating normally and is allowed to be opened during cold water replenishment. A tee device and an instrument pipeline are added to the instrument pipeline from the balancing container tank to the transmitter to increase the water replenishment interface and the water replenishment pipeline, wherein the size of the tee is The water supply pipeline is connected by a tee. The pipeline material is carbon steel; the carbon steel instrument pipe is connected to each water supply port by butt welding to ensure that each interface can withstand high pressure and is strong and reliable. The automatic water supply method of a single-chamber liquid level gauge includes a water supply tank for providing water source, a tee on the instrument pipeline for connecting the balance container tank, a pump for conveying water source to the water inlet, and a manual stop valve for ensuring the sealing of the system during operation. The water supply tank, pump, manual stop valve and tee are connected in sequence through the instrument pipeline.
Claims
1. An automatic water replenishment device for a single-chamber liquid level gauge in a nuclear power plant, characterized in that: It includes DN50 pipeline, manual stop valve A, manual stop valve B, manual stop valve C, manual stop valve D, manual stop valve E, manual stop valve F, manual stop valve G, tee A, tee B, tee C and newly added instrument pipeline; the DN50 pipeline is connected with the primary water supply pump, and the DN50 pipeline is provided with a manual stop valve A, which is connected with the manual stop valve B and the manual stop valve C in sequence, and the tee A is respectively connected with the manual stop valve C, the balancing container tank A and the evaporator tube side liquid level gauge; the manual stop valve A is connected with the manual stop valve D and the manual stop valve E in sequence, and the tee B is respectively connected with the manual stop valve E, the balancing container tank B and the evaporator shell side liquid level gauge; the manual stop valve A is connected with the manual stop valve F and the manual stop valve G in sequence through the newly added instrument pipeline, and the tee C is respectively connected with the manual stop valve G, the balancing container tank C and the original instrument pipeline.
2. The automatic water replenishing device for a single-chamber liquid level gauge in a nuclear power plant according to claim 1 is characterized in that: The primary water supply tank is connected to the primary water supply pump.
3. The automatic water replenishing device for a single-chamber liquid level gauge in a nuclear power plant according to claim 1 is characterized in that: The original instrument pipeline is connected to the deaerator level gauge.
4. The automatic water replenishing device for a single-chamber liquid level gauge in a nuclear power plant according to claim 1 is characterized in that: The primary feed water pump delivers the feed water to the subsequent system.
5. The automatic water replenishing device for a single-chamber liquid level gauge in a nuclear power plant according to claim 1 is characterized in that: All manual stop valves are closed during normal operation and opened when replenishing water.
6. The automatic water replenishing device for a single-chamber liquid level gauge in a nuclear power plant according to claim 1, characterized in that: The new instrument pipeline material is carbon steel.