Dual-purpose remote-control grab for fuel elements and control rods of a

Abstract

An apparatus for inserting and removing both control rods and fuel elements from holes in a nuclear reactor has a vertically and horizontally displaceable support pivotally carrying a head which has a pair of grabs on its opposite ends, one of which is formed as a pair of pawls adapted to lock on the collar at the end of a fuel element and lift this element and the other of which is adapted to engage within a group of control rods to unlock them from their respective fuel elements and grip them so that they can be lifted from the respective fuel element. To this end the housing having the two grabs is provided with a small pneumatic cylinder whose piston is displaceable against spring force in one direction and is connected to both of the grabs so that on displacement in this direction it opens both of the grabs, the spring therefore serving to hold these grabs closed should pneumatic pressure fail. The grab head is pivotal on the support about a horizontal axis on pins serving as the pivot for this head and provided with pinions meshing with racks that can be displaced up and down so as to rotate the head through 180.degree., thereby aligning either of the grabs with a respective object. In addition locking means is provided so as to hold this head in either of these positions, thereby preventing it from tilting and dropping a group of control rods or a fuel element.