ACTUATOR OF NUCLEAR-REACTOR CONTROL AND PROTECTION SYSTEM Russian patent published in 2002 - IPC

FIELD: nuclear reactors. SUBSTANCE: actuator has vertical dry case accommodating peripheral sleeves with neutron absorbers, central sleeve with axially displacing hanger joined to servodrive flexible control link, and brackets passed through vertical slits between peripheral sleeves and central sleeve for linking hanger to absorbers; novelty is that actuator is made for introducing absorption rods in core throughout its entire height from bottom upwards. Absorbing rods are divided into top and bottom assemblies, their length being of the order of that of case sleeves in section below core; top assemblies are free to move in peripheral sleeves without axial displacement relative to hanger; bottom assemblies are arranged for axial telescopic displacement relative to hanger and for alternate movement within central and peripheral sleeves (with lower ends of top assemblies below the lower boundary of core and above it, respectively). As an alternative bottom assemblies of absorbers are arranged for axial displacement within central sleeve only. Absorber hanger in each alternative is provided with remote-control bayonet connector for locking absorbing rods in axial position as soon as they are fully entered in core to reduce probability of their spontaneous escape from core in case of breakage of servodrive control link. In this way energy release is mainly controlled in bottom part of core during full-power running of reactor and maximum of reactivity input is attained during reactor shutdown. EFFECT: enhanced nuclear safety. 3 cl, 1 dwg