[en] The hoisting and gripping device for the rod-shaped fuel, breeder, or absorbing elements can be moved along a slot in the rotating shield, this one being coaxially supported on the reactor vessel head. The slot may extend radially along the whole or part of the rotating shield. In this way, shuffling of the elements as well as access to the whole cross section of the vessel is possible. Escape of radioactive radiation or of cover gas from the vessel or ingress of air into it is prevented by means of a shielding box. It seals the slot gastight without interfering with the free movability of the hoisting and gripping device. For pretection of the hoisting unit against impurities from the reactor atmosphere a convection barrier may be provided. It consists of two bellows which are connected on one side with the slot and on the other with a wagon carrying the hoisting unit. (orig./PW)