Patent Number: 055703992
Section: abstract

A control rod and fuel supporting member gripping apparatus for gripping a fuel supporting member and a control rod is disposed in a reactor pressure vessel. The fuel supporting member is mounted on a core supporting plate and has fuel assembly supporting holes in which the bottom portions of fuel assemblies are inserted. The control rod is detachably connected with a control rod driving mechanism through a bayonet coupling and is passed through a control rod passage so as to be lifted up and down in order to remove the fuel supporting member and the control rod from the core supporting plate and the control rod driving mechanism. The control rod and fuel supporting member gripping apparatus comprises a gripping apparatus body hoisted vertically liftably in an installed state within the reactor pressure vessel, a fuel supporting member gripping device disposed at a portion below the gripping apparatus body, a control rod gripping device device disposed at a portion below the gripping apparatus body to be liftable up and down and rotatable with respect to the gripping apparatus body, and a rotating mechanism for rotating the control rod gripping device.. In withdrawing the control rod and fuel supporting member from the reactor pressure vessel, the fuel supporting member is raised to a height above the control rod and is prevented from rotating, the control rod is thereafter rotated, and the fuel supporting member and the control rod are withdrawn from the reactor pressure vessel substantially at the same time.