CONTAINMENT SHIELDING SYSTEM FOR WATER-MODERATED REACTOR UNIT Russian patent published in 1998 - IPC

FIELD: nuclear reactors. SUBSTANCE: concrete cavity has annular header communicating at its bottom with reactor room through wide-profile passages, coolant feeder connecting steam generator boxes with annular header, and device for discharging coolant from concrete cavity that provides communication between upper part of cavity and steam generator boxes. Mounted on reactor room floor is drainage system that carries basket filled with high- melting elements with voids. High-melting elements mount water-tight restricting cover with central hole for passing coolant and with supporting ribs carrying safety shell that fully closes bottom and lower part of reactor cylindrical vessel. Inner side of safety shell mounts heat-resistant high-melting elements ensuring high thermal resistance which ensures heat transfer through safety shell to coolant without its overheating or damage in case of vessel bottom destruction by corium. EFFECT: improved safety of nuclear reactor unit in case of core disruptive accident and corium escape beyond reactor. 8 cl, 5 dwg