Measuring Instrument Installation Device for Spent Fuel Pool of Nuclear Power Plants in Service

Abstract

The invention relates to an installation device for a measuring instrument of an in-service spent fuel pool in a nuclear power plant. The installation device comprises an installation support and a measuring instrument installation component fixed on the installation support, wherein the installation support is suspended on the side wall of the spent fuel pool, and comprises a support plate which is vertically suspended on the side wall of the spent fuel pool, and an upper installation plate and a lower installation plate which are horizontally arranged on the support plate; the measuring instrument installation component comprises an outer sleeve; the outer sleeve passes through the upper installation plate and the lower installation plate from top to bottom and is fixedly connected with the upper installation plate; the measuring instrument is inserted in the outer sleeve. By virtue of the installation device, the measuring instrument can be installed on the in-service spent fuel pool on line, the capability of monitoring the in-service spent fuel pool in the nuclear power plant is enhanced, the measuring instrument of the spent fuel pool is not damaged during and after a serious accident, and the instrument can be detected regularly on line without being detached.

Description

technical field [0001] The invention belongs to the technical field of nuclear industry measurement, and in particular relates to a measuring instrument installation device for a spent fuel pool of an in-service nuclear power plant. Background technique [0002] The spent fuel pool is used as a storage place for spent fuel. As long as there is spent fuel in the pool, it must be filled with water and maintain a normal water level to provide the necessary safe biological protection; at the same time, the pool water must be cooled to remove the residual heat of spent fuel elements in a timely manner. . [0003] In the large-scale nuclear leak caused by the Fukushima earthquake on March 11, 2011, the measuring instruments used to monitor the state of the spent fuel pool lost their function under the harsh environmental conditions of the severe accident. Due to the loss of the monitoring of the parameters of the pool, the bad condition of the pool cannot be discovered in time, m...

AI Technical Summary

Problems solved by technology

[0003] In the large-scale nuclear leakage incident caused by the Fukushima earthquake in Japan on March 11, 2011, the measuring instruments for monitoring the state of the spent fuel pool lost their functions under the harsh environmental conditions of the severe accident

[0005] For nuclear power plants in service, since spent fuel assemblies are stored in the spent fuel pool, and the spent fuel pool is filled with water, the biological shielding layer cannot be damaged. Therefore, it is necessary to open the spent fuel pool to measure the water level of the spent fuel pool by using a conventional differential pressure transmitter. hole, which will destroy the sealing of the exhausted pool, and will bring great hidden dangers to the safety of the exhausted pool, so the only choice is the contact measuring instrument inserted into the pool from the top of the exhausted pool

Since the liquid level measurement of the spent fuel pool requires the measurement of the liquid level from the top of the fuel grid to the full water level of the spent fuel pool, the probe rod of the instrument is nearly 9 meters long. During the implementation of the nuclear power plant under construction, the instrument casing needs to pass through the inner wall of the spent fuel pool The embedded parts of the existing rooting anchor brackets are fixed to ensure the fixed installation requirements and seismic requirements of the instrument, while other At the same time, underwater welding construction operations can no longer be carried out, and there are strict nuclear cleaning requirements during poolside construction, and any foreign matter falling into the pool is prohibited

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