DEVICE FOR CHECKING COOLING WATER FLOWRATE IN PRIMARY CIRCUIT OF PRESSURIZED-TUBE REACTOR Russian patent published in 2004 - IPC

FIELD: nuclear reactors. SUBSTANCE: device designed for controlling primary coolant flowrate in pressurized-tube reactor of RBMK series where contact with coolant is not required depends for its operation on recording changes in gamma-activity of ¹⁶N isotope in coolant by means of detectors distributed along process channel, these changes resulting from radioactive decay of this isotope during water flow over process channel between distributed detectors. ¹⁶N activity will be checked over gamma-radiation lines at quanta energy of 7.12 and 6.13 MeV that will be evolved from background radiation by means of detector depending for its operation on recording coincidence of pulses coming from two electron counters separated by electron absorbers at energy about 6 MeV. Included in device is electronic unit coupled with detectors by means of electric lines; this unit functions to separate and record detector signals proportional to ¹⁶N activity in coolant and can calculated water flowrate in process channel. EFFECT: enhanced reliability and in-service safety of device. 1 cl, 1 dwg