CORROSION POTENTIAL MEASURING DEVICE AND CORROSION POTENTIAL MEASURING METHOD FOR NUCLEAR POWER PLANT

摘要

PROBLEM TO BE SOLVED: To provide a corrosion potential measuring method capable of accurately measuring a state of an SCC countermeasure apparatus in a lower plenum, in such a manner that it is made to be hard to receive the influence of an apparatus in which a corrosion potential sensor is installed when measuring a corrosion potential within the lower plenum of a pressure vessel of a BWR.SOLUTION: In a nuclear power plant having an LPRM pipe provided with a corrosion potential sensor, an outer cylinder tube recess for installing the corrosion potential sensor is provided on an outside surface of the LPRM; the corrosion potential sensor is installed in the outer cylinder tube recess; sensor protective members for protection are installed at the upper and lower positions of the corrosion potential sensor; and the corrosion potential sensor is installed, in such a manner that each of a distance from a potential detection part of the corrosion potential sensor to a recess outside surface of the LPRM pipe, a distance from the potential detection part of the corrosion potential sensor to a casing of the corrosion potential sensor, and distances from the potential detection part of the corrosion potential sensor to the sensor protective members is longer than a distance from the potential detection part of the corrosion potential sensor to an in-core monitor guide tube.