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

摘要

A method of removing the upper internals assembly from a nuclear reactor pressure vessel for refueling that simultaneously disconnects two or more of the in-core instrument thimble assemblies from the reactor vessel penetrations through which their signal cables extend. The signal cables are connected to the penetrations with an electrical connector that supports the two or more in-core instrumentation thimble assembly signal leads. Before the electrical connector is disconnected, water in the vessel is lowered below the connection so that the process is performed in a dry environment.