Nuclear island water system sealing measurement device and method

Abstract

The invention discloses a nuclear island water system sealing measurement device and method. The measurement device comprises: a water tank which is provided with a liquid level sensor and a temperature sensor; a water filling pipeline, a pressurizing pipeline, an exhaust pipeline and a test connecting pipeline which are all connected with the water tank; a control module used for calculating a water leakage volume according to the water level change in the water tank, converting the water leakage volume into a gas leakage volume, correcting the gas leakage volume to a standard condition according to the temperature measured by the temperature sensor, and calculating the leakage amount of the valve to be measured; and a display screen used for displaying the test related parameters and thetest result. Compared with like devices and methods in the prior art, the device and the method of the invention have the advantages that a to-be-tested system does not need to be filled with water and drained repeatedly in the test period, so the test time is shortened, and the problem that the system function is affected by rust slag and the like due to the fact that a water system is not filled with water for a long time can be prevented; and moreover, the device and the method have the advantages of high test precision, reliable data result, simple equipment operation, small size, portability, real-time display of measurement results and the like.

Description

technical field [0001] The invention belongs to the field of sealing performance test of containment isolation valve of nuclear power plant, more specifically, the invention relates to a nuclear island water system sealing measuring device and measuring method. Background technique [0002] A mechanical penetration is a fluid transfer line that runs through the reactor containment building, which is part of the third barrier of a nuclear power plant. The first isolation valve installed on the inner and outer sides of the concrete in the fluid transmission pipeline is called the containment isolation valve, which plays an important role in preventing reflective materials in the island from flowing out of the island in the event of a LOCA accident. Therefore, the containment isolation valve is also a boundary of the containment suppression test. Before the start of the containment suppression test, it is necessary to complete the sealing test of the penetration isolation valve...

AI Technical Summary

Problems solved by technology

However, the downstream pipeline space of systems such as on-site RIS / EAS / RRI / DEG is very large, and it takes a very long time to fill the entire pipeline through the leakage of the valve to be measured, which affects the progress of the on-site test

During the service period, the radiation dose of the test personnel was increased due to the long waiting time

[0013]Third, it affects the system construction period: the water system of the nuclear island has wet maintenance requirements, and it is full of water under normal working conditions. According to the current plan, the system must be Empty the inner water to carry out the sealing test, and then fill the system with water after the sealing test. Taking RRI / RIS / DEG as an example, it takes 2 days for some penetrations to drain the water, and 1 day to fill the water after the test , which seriously affects the commissioning period of the on-site system and restricts the critical path

[0014]Fourth, affecting system functions: Some system pipes are carbon steel pipes, rust residue will appear in the pipes without wet maintenance for a long time, affecting system functions

[0015] Fifth, low precision: the current flowmeter is a rotameter with a precision of 5%. The error can reach 9000cm3 / h*5%=450cm3 / h

[0016]Sixth, the measuring range is narrow: the minimum flow rate among the three flowmeters is 280cm3 / h, which cannot meet the minimum leakage limit of the EPR unit 128cm3 / h requirement, the maximum range of the three flowmeters is 9000cm3 / h, that is, the leakage rate cannot be measured after exceeding 9000cm3 / h Leaking the real value cannot bring maintenance reference for valve maintenance

[0017] Seventh, the measurement error is large: such as Figure 1, the premise of the slight positive pressure of the gas in the pipeline is that the pipeline is a complete closed space

And if the downstream valve t5 also leaks internally, the gas leaked from the upstream valve t3 to be tested into the pipeline will leak out through the downstream valve t5, resulting in a large error in the measurement of the leakage of the upstream valve t3 to be tested

Images