DIRECT-ACTION REACTIVITY CONTROL DEVICE FOR NUCLEAR REACTOR Russian patent published in 1998 - IPC

FIELD: nuclear engineering; nuclear-reactor control and emergency shutdown devices. SUBSTANCE: functions of neutron- absorbing and conducting members are performed by single structural member of device to control reactivity of nuclear reactor which makes it possible to dispense with electromechanical coupling between neutron-absorbing and drive members thereby eliminating probability of wedging of mechanical-coupling members and other failures. In addition, such arrangement provides for designing direct-action (passive) emergency safety gear of reactor whose performance characteristics depend only on core temperature and neutron flux density. Device has neutron- absorbing member with varying neutron-absorbing surface made of common-axis plates coated with neutron-absorbing material. Plates are made of material possessing thermomechanical shape memory and function as drive member; they are twisted into spiral about common axis to form roll. EFFECT: simplified design, improved stability of characteristics, and reduced failure probability. 7 cl, 3 dwg