Boiler drum water level monitoring and alarming device

Abstract

The utility model relates to the technical field of on-line instrument measurement, in particular to a boiler drum water level monitoring and alarming device, and aims to solve the problems that the real drum water level of a boiler is difficult to reflect accurately due to the fact that a common mode is influenced by boiler pressure and the like in the existing evaporative cooling or boiler drum water level measurement. And the operation safety and the operation quality of the boiler are easily reduced. According to the device, the boiler drum water level is monitored by redundant measurement of a guided wave radar liquid level meter, redundant measurement of an electric teletransmission magnetic flap liquid level meter and redundant measurement of a double-chamber balancing container, so that the accuracy and the safety of a boiler drum water level measuring instrument under extreme pressure and temperature conditions are favorably guaranteed; when the water level of the detected steam drum deviates from a specified value or the running state is abnormal, a sound-light alarm is given to remind an operator on duty to make correct judgment, the uncertainty risk is reduced, and it is ensured that the water level of the steam drum is in a safe running state.

Description

Technical Field

[0001] This utility model relates to the field of online instrument measurement technology, specifically to a boiler drum water level monitoring and alarm device. Background Technology

[0002] In vaporization cooling or boiler drum automatic level control systems, the controlled parameter, the boiler drum level, is a key indicator of normal boiler drum operation. An excessively high level can affect steam-water separation, causing liquid carryover in the steam and deteriorating steam quality; an excessively low level is detrimental to water circulation, potentially leading to localized overheating of the water-cooled walls, tube rupture, or even boiler burnout – serious accidents. Therefore, the boiler drum level metering system is an extremely important system for the safe operation of the unit. To ensure safe boiler operation, the boiler drum water level must be maintained within an allowable range, specifically within ±50mm of zero water level. This requires the corresponding boiler drum water level measurement system to be accurate and reliable. Currently, there are three main methods for measuring the water level in vaporization cooling or boiler drum: local bicolor water level gauges, electric contact water level gauges, and differential pressure water level gauges. The measurement errors of local water level gauges, electric contact water level gauges, and differential pressure water level gauges are affected by boiler pressure, heat dissipation, installation method, and measurement method. They are difficult to accurately reflect the true water level in the boiler drum and cannot meet the requirements for boiler operation safety and quality. They also have significant gaps in reliability and ease of maintenance compared to the objective requirements of engineering applications. Utility Model Content

[0003] This invention provides a boiler drum water level monitoring and alarm device to solve the problems mentioned above.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A boiler drum water level monitoring and alarm device includes a boiler drum. Electrically transmitted level gauges are symmetrically arranged on both sides of the boiler drum's interior. Each of the electrically transmitted level gauges extends outwards from the boiler drum and is equipped with a drain valve. Guided wave radar level gauges are connected to both sides of the boiler drum's outer wall. A dual-chamber balance vessel is connected to the side of each guided wave radar level gauge. Each dual-chamber balance vessel is connected to a differential pressure transmitter. Both dual-chamber balance vessels are also connected to the boiler drum via downcomers. The differential pressure transmitter is also connected to a current detection safety barrier. The current detection safety barrier is connected to a flashing alarm and a PLC controller, and the current detection safety barrier is also connected to the guided wave radar level gauge.

[0006] Furthermore, a flap box is fixedly installed on both sides of the inside of the boiler drum, and the remote-controlled level gauge is fixedly connected to the flap box. The bottom of the remote-controlled level gauge is also equipped with a remote-controlled transmitter.

[0007] Furthermore, multiple shut-off valves are provided at the outlets on both sides of the outer wall of the boiler drum, and the guided wave radar level gauges are all connected to the shut-off valves.

[0008] Furthermore, the guided wave radar level gauge has a bypass pipe on its side, which is connected to the dual-chamber balance container, and the reference cup of the dual-chamber balance container is connected to the differential pressure transmitter.

[0009] Furthermore, the bottom of the guided wave radar level gauge is connected to a drain valve, the bottom of the dual-chamber balance container is equipped with a condensate drain valve, and a three-valve group is provided between the guided wave radar level gauge, the dual-chamber balance container and the differential pressure transmitter.

[0010] Furthermore, the flashing alarm is also connected to an electric bell, a test button, and a confirmation button.

[0011] This utility model has the following beneficial effects:

[0012] This utility model consists of an externally connected bypass cavity, which is installed on the side of the boiler drum via a process interface. Its liquid level is the same as that inside the tank. The guided wave radar level gauge, the dual-chamber balance container, and the side-mounted electric remote transmission magnetic level gauge installed on the side of the boiler drum can be completely separated from the main container, the boiler drum, via a field valve.

[0013] This utility model, the VEGAFLEX86 guided wave radar level gauge, is suitable for liquids operating under extreme pressure and temperature conditions of 0-450℃ and 0-40MPa. It enables long-term stable, reliable, and accurate measurement of guided wave radar level gauges in applications involving high temperature, high pressure, steam, or condensate.

[0014] This invention employs a double-chamber balancing container, a steam drum water level measuring device with a certain self-compensation capability. Through good insulation, the water temperature inside the balancing container is made close to the steam drum water temperature, and is less affected by the ambient temperature.

[0015] This utility model adopts the KM26SS side-mounted electric remote transmission magnetic float level gauge, which is used for liquids under extreme pressure (0-31MPa) and temperature (0-+538℃) conditions. The measurement accuracy is ±5mm, and the signal output is 4-20mA DC / HART, which can display locally and transmit remotely.

[0016] When the boiler drum liquid level deviates from the specified value or the operating status is abnormal, this utility model will issue an audible and visual alarm to remind the on-duty personnel to make the correct judgment, reduce uncertainty risks, and ensure that the boiler drum liquid level is in a safe operating state.

[0017] To avoid unnecessary false alarms due to spurious signals, the boiler drum liquid level parameter of this utility model adopts a multi-sensor control logic and defines a delay. When the early warning system receives a signal exceeding the trip limit, the signal is simultaneously confirmed by two independent guided wave radar level gauges or two independent differential pressure level gauges. Only when the limit is exceeded within a specified time will a danger alarm signal be issued. This effectively avoids serious equipment accidents, greatly improves the safety of boiler drum operation, and reduces economic losses. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0019] The meanings of the reference numerals in the attached figures are as follows:

[0020] 1. Boiler drum; 2. Flip-plate box; 3. Electrically transmitted level gauge guide pipe; 4. Electrically transmitted level gauge; 5. Float; 6. Electrically transmitted transmitter; 7. Drain valve; 8. Guided wave radar level gauge; 9. Flange; 10. Rod-type guided wave antenna; 11. Shut-off valve; 12. Bypass pipe; 13. Condensate chamber; 14. Dual-chamber balance vessel; 15. Reference cup; 16. Communicating vessel; 17. Overflow chamber; 18. Condensate drain valve; 19. Three-valve manifold; 20. Differential pressure transmitter; 21. Downcomer; 22. Current detection safety barrier; 23. PLC controller; 24. Flashing alarm; 25. Electric bell; 26. Test start button; 27. Confirmation button. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown, a boiler drum water level monitoring and alarm device includes a boiler drum 1. Electrically transmitted level gauges 4 are symmetrically arranged on both sides of the interior of the boiler drum 1. Each of the electrically transmitted level gauges 4 extending outwards from the boiler drum 1 is equipped with a drain valve 7. Guided wave radar level gauges 8 are connected to both sides of the outer wall of the boiler drum 1. A dual-chamber balance vessel 14 is connected to the side of each guided wave radar level gauge 8. Each dual-chamber balance vessel 14 is connected to a differential pressure transmitter 20. Each dual-chamber balance vessel 14 is also connected to the boiler drum 1 via a downcomer 21. The differential pressure transmitter 20 is also connected to a current detection safety barrier 22. The current detection safety barrier 22 is connected to a flashing alarm 24 and a PLC controller 23, and the current detection safety barrier 22 is also connected to the guided wave radar level gauges 8.

[0023] The boiler drum 1 has a flap box 2 fixedly installed on both sides inside. The electric remote level gauge 4 is fixedly connected to the flap box 2. The bottom of the electric remote level gauge 4 is also equipped with an electric remote transmitter 6.

[0024] Multiple shut-off valves 11 are provided at the outlets on both sides of the outer wall of the boiler drum 1, and the guided wave radar level gauges 8 are all connected to the shut-off valves 11.

[0025] A bypass pipe 12 is provided on the side of the guided wave radar level gauge 8. The bypass pipe 12 is connected to the dual-chamber balance container 14, and the reference cup 15 of the dual-chamber balance container 14 is connected to the differential pressure transmitter 20.

[0026] The bottom of the guided wave radar level gauge 8 is connected to a drain valve 7, and the bottom of the dual-chamber balance container 14 is provided with a condensate drain valve 18. A three-valve group 19 is provided between the guided wave radar level gauge 8, the dual-chamber balance container 14 and the differential pressure transmitter 20.

[0027] The flashing alarm 24 is also connected to an electric bell 25, a test button 26, and a confirmation button 27.

[0028] In practical applications, the guided wave radar level gauge 8, differential pressure transmitter 20, and remote electrical transmitter 6 are connected to the current detection terminal safety barrier 22 via signal cables. The current detection terminal safety barrier 22 outputs two 4-20mA current signals to the PLC controller 23, and outputs two relay contact signals to the flashing alarm 24. The PLC controller 23 outputs three switching signals to the input terminal of the flashing alarm 24.

[0029] The guided wave radar level gauge 8 uses a VEGAFLEX 86 rod-type guided wave antenna 10, suitable for applications involving liquids with deposits, foaming, or condensation under extreme pressure conditions of -1 to +400 bar and temperatures of -196 to +450°C. It offers a measurement accuracy of ±2 mm and a signal output of 4-20 mA DC / HART. The side-mounted remote-reading level gauge 4 uses a K-TEK KM26SS, suitable for liquids under extreme pressure conditions of 0-31 MPa and temperatures of -195 to +538°C. It offers a measurement accuracy of ±5 mm and a signal output of 4-20 mA DC / HART. The current sensing safety barrier 22 is a dual-input, dual-output type, with 4-20 mA input and output, two relays, a power supply voltage of 220V AC, a permissible load RL ≤ 550Ω, a contact capacity of 250VAC / 2A or 30V / 2A, a conversion accuracy of 0.1%FS, and a response time ≤ 500ms. The input terminals of the flashing alarm 24 are connected to the alarm output channel of the current detection terminal safety barrier 22, and the other terminals are connected to the electric bell 25, the test button 6, and the confirmation button 27. When the flashing alarm 24 is turned on, the electric bell 25 is also turned on. The flashing alarm 24 emits a light source, and the electric bell 25 emits a sound, realizing an audible and visual alarm. When the test button 26 is closed, the flashing alarm 24 is turned on. When the confirmation button 27 is closed, the flashing alarm 24 is turned off. The test button 26 and the confirmation button 27 are used to confirm whether the flashing alarm 24 is working properly.

Claims

1. A boiler drum water level monitoring and alarm device, comprising a boiler drum (1), characterized in that: The boiler drum (1) is symmetrically equipped with electric remote level gauges (4) on both sides inside. Each electric remote level gauge (4) is equipped with a drain valve (7) extending outward from the boiler drum (1). Both sides of the outer wall of the boiler drum (1) are connected to guided wave radar level gauges (8). Each side of the guided wave radar level gauge (8) is connected to a dual-chamber balance container (14). Each dual-chamber balance container (14) is connected to a differential pressure transmitter (20). Each dual-chamber balance container (14) is also connected to the boiler drum (1) through a downcomer (21). The differential pressure transmitter (20) is also connected to a current detection end safety barrier (22). The current detection end safety barrier (22) is connected to a flashing alarm (24) and a PLC controller (23). The current detection end safety barrier (22) is also connected to the guided wave radar level gauge (8).

2. The boiler drum water level monitoring and alarm device according to claim 1, characterized in that: The boiler drum (1) has a flap box (2) fixedly installed on both sides inside. The electric remote level gauge (4) is fixedly connected to the flap box (2). The bottom of the electric remote level gauge (4) is also equipped with an electric remote transmitter (6).

3. The boiler drum water level monitoring and alarm device according to claim 2, characterized in that: The boiler drum (1) has multiple shut-off valves (11) on both sides of its outer wall outlet, and the guided wave radar level gauge (8) is connected to the shut-off valves (11).

4. The boiler drum water level monitoring and alarm device according to claim 3, characterized in that: The guided wave radar level gauge (8) has a bypass pipe (12) on its side, which is connected to the dual-chamber balance container (14), and the reference cup (15) of the dual-chamber balance container (14) is connected to the differential pressure transmitter (20).

5. A boiler drum water level monitoring and alarm device according to claim 4, characterized in that: The bottom of the guided wave radar level gauge (8) is connected to a drain valve (7), and the bottom of the dual-chamber balance container (14) is provided with a condensate drain valve (18). A three-valve group (19) is provided between the guided wave radar level gauge (8), the dual-chamber balance container (14) and the differential pressure transmitter (20).

6. The boiler drum water level monitoring and alarm device according to claim 1, characterized in that: The flashing alarm (24) is also connected to an electric bell (25), a test button (26) and a confirmation button (27).

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