Static strength calculation of DN 350 branch pipe cutting-in in the main circulation pipeline of reactor plant WWER-1000

Nowadays the total electricity generated in nuclear power plants in Russian Federation is approximately 18% of all power generation. There are 36 reactors in operation in Russia, 19 of which are reactor plants WWER-1000. A planned operation lifetime of these plants is 30 years and most of them have served for this period. To extend reactor working lifetime it is necessary to carry out the calculation for possibility justification of continued operation of reactor equipment and pipelines. The paper presents the static strength calculation of DN 350 branch pipe cutting-in in the main circulation pipeline of reactor plant WWER-1000. According to calculation results a following conclusion is made: if the static strength of DN 350 branch pipe cutting-in meets the requirements of technical standard, the continued operation of this pipeline section will be possible

Evaluation of neutron activation of intermetallic matrices for dispersive nuclear fuel obtained by SH-synthesis

The paper describes a technique for obtaining intermetallic matrix materials based on Zr-Al and Ni-Al systems for dispersive nuclear fuel. This type of fuel is planned to be used in existing and future high-temperature nuclear reactors. Physical and mathematical modelling of the process of activation of matrices by neutron radiation showed that upon reaching the value of thermal neutron fluence of the order of 2.76·1021 n·cm-2 , the activity of Zr-Al and Ni-Al matrices was 1.3·1010 and 0.2·1010 Bq/g, respectively. The analysis showed that in terms of exposure of irradiated fuel it is preferable to use a matrix based on the zirconium-aluminium system