Instrumentation device for the core of a nuclear water-pressurized reactor, and method and device for removing and installing this instrumentation device

摘要

The instrumentation arrangement comprises a horizontal plate (31) arranged below the vessel (1) closure head (3) through which instrumentation columns (27) pass, carrying measurement conduits internally (26). The distribution plate (31) carries vertical guide tubes (38), into each of which a measurement conduit (26) is introduced. Each of the vertical guide tubes (38) is engaged into a tubular brace (17) of the upper internal equipment of the reactor, to ensure the guidance of the measurement conduit (26), from the instrumentation column (27) to an instrumentation guide tube (30) of a reactor core assembly (5). The distribution plate (31) is fastened in a removable manner to the plate (18) supporting the upper internal equipment of the reactor and may be raised relative to the upper internal equipment for withdrawing, as a unit, the measurement conduits (26) from the instrumentation tubes of the core assemblies, when the closure head (3) is removed.