Method of pulling out the in-core instrument from the core of a pressurized water reactor

摘要

A method of removing the upper reactor structure assembly from the reactor pressure vessel for refueling. Two or more in-core instrumented thimble assemblies are simultaneously disconnected from the reactor vessel penetration portion through which the signal cable of the in-core instrumented thimble assembly passes. The signal cable is connected to the penetrating portion by an electrical connector that supports signal lead wires of the two or more in-core instrumented thimble assemblies. Since the electrical connector wiring is removed after the water level in the container is lowered below the connecting portion, the process is performed in a dry environment. [Selection] Figure 8