Nuclear power plant water storage tank liquid level switch calibration device and method

Abstract

The invention discloses a nuclear power plant water storage tank liquid level switch calibration device and method, and the device comprises a temporary water storage tank which is provided with a water outlet pipeline which is connected with the top end and the bottom end of a liquid level column, and is used for providing a storage container for the charging and discharging of the liquid level column, the metering pump is arranged on a water outlet pipeline of the temporary water storage tank and used for filling water into the liquid level column, the temporary liquid level meter is parallel to the liquid level column, the bottom of the temporary liquid level meter is connected with the bottom of the liquid level column, and the temporary liquid level meter is used for monitoring liquidlevel in the liquid level column, and the data acquisition and processing device is used for acquiring signals of the plurality of liquid level switches and the liquid level monitoring meter in realtime and processing, displaying and storing the signals. Compared with the prior art, the method has the advantages that the problems of low verification precision, untrusted verification result, verification risk and high cost of an original verification mode are solved, the verification work efficiency of the liquid level switch of the water storage tank is improved, human errors are reduced, and moreover, the risk of influencing safe operation of a unit due to multiple times of verification of the liquid level switch is further reduced.

Description

technical field [0001] The invention belongs to the field of debugging of nuclear power plants, and more specifically, the invention relates to a verification device and method for a liquid level switch of a water storage tank of a nuclear power plant. Background technique [0002] The auxiliary water supply system (ASG) is used as the evaporator water supply backup system to provide water to the secondary side of the evaporator when the main water supply is lost. When the reactor is started and the temperature of the reactor coolant system is raised, the nuclear power unit is thermally shut down, and the reactor is cooled until the residual heat removal system (RRA) is put into operation, it replaces the operation of the main water supply system (ARE) and the start-up water system (APD); the auxiliary water supply system belongs to the exclusive Safety facilities are set up. When any normal water supply system (APA, APD, ARE) fails, the auxiliary water supply system operate...

AI Technical Summary

Problems solved by technology

[0021] However, the above liquid level switch fixed value verification method has the problems of low verification accuracy, unreliable test results, high risk in the verification process, and high test cost:

[0022] 1) For the first time, the calibration and adjustment of the liquid level switch is realized by filling and draining the liquid level column 001CN. The calibration and adjustment process of the liquid level switch uses the temporary liquid level gauge as a reference, because the temporary liquid level gauge has the problem of low measurement accuracy , so the existing verification method has the problem of low accuracy of verification results;

[0023] 2) The liquid level column 001CN was filled and drained many times on site to adjust and verify the liquid level switch. Because the opening of the valves 803VD and 807VD were manually controlled during the water filling and draining process, the filling and draining rate during each verification process are different, resulting in a deviation between the test results and the trigger verification value of the liquid level switch during the filling and draining of the water storage tank ASG001BA, which ultimately makes the test results unreliable;

[0024] 3) During the filling and draining of the liquid level column 001CN for many times, because the water filling rate cannot be effectively controlled, the connecting rod of the liquid level switch often bends due to the excessive water filling rate; at the same time, because the early test results are not reliable, the subsequent The number of adjustments of the liquid level switch during the filling and draining of the water storage tank ASG001BA increases the risk of nitrogen suffocation and high-altitude fall;

[0025] 4) Due to the rough verification of the liquid level switch with a temporary liquid level gauge in the early stage, it is necessary to fill and drain the water storage tank ASG001BA several times in the later stage to verify and adjust the liquid level switch, increase the test water by about 2000 cubic meters, and increase the verification period About 6 days, increasing the test cost

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