METHOD FOR IMPROVING PRESSURE-TUBE REACTOR CORE Russian patent published in 2002 - IPC

FIELD: servicing pressure-tube reactor cores. SUBSTANCE: proposed method intended for improving reactor core during major repairs including replacement of process channels as soon as preset channel-by-channel energy output is attained in reactor cells involves step-by-step replacement of process channels; during first step channels in which both energy production and inner diameter are beyond threshold value specified for this step and those in which metal integrity is disturbed are replaced. In addition threshold value of energy production at preset process clearance is proposed to be determined from curves showing clearance as function of energy production and threshold inner diameter at preset process clearance is to be found from curves showing inner diameter as function of process clearance; it is also proposed to detect and replace during ultrasonic inspections the channels in which cracks of 0.3 mm and more are revealed in steel-to-zirconium intermediate joint. EFFECT: enhanced effective period of each process channel; increased energy output. 4 cl, 3 dwg