The welded connections of the main circulation line at the Leningrad NPP power block No.1 being constructed are completed in a proper way and comply with the technical specification, which was confirmed during the issue-related verification carried out jointly by the representatives of the Leningrad NPP and VNIIAES. The latter acts as a research advisor on the Russian nuclear plants operation. The Rosenergoatom Concern OJSC Chief Executive Officer has ordered this examination to address the public concerns regarding the new power blocks’ construction technologies.

Additionally, the experts have verified all 28 field joints of the main circulation line (MCL), those being: MCL’s connection to the reactor’s housing tubes, the steam generator, the main circular pumping module, and the MCL’s enlarged blocks connection between each other.

“In order to confirm that each joint meets the standards, we have carried out several non-destructive tests: visual and instrumental, capillary, and ultrasound. The data received coincide with the verification results provided by the TITAN-2 Holding during the MCL mounting. In both cases the examinations stuck to the roadmaps elaborated and approved by NIKIMT-Atomstroy, which is the head material organization of Rosatom”, said Vladimir Pereguda, the Leningrad NPP director.

“Our colleagues from VNIIAES and the Central Research and Development Institute “Atomenergomash” have completed additional checks verifying that the base metal and the MCL welded connection metal stress-related properties are in line with the codes and standards. No changes in the metal microstructure expected for welding with no subsequent hear processing were identified at the sites under control”, the deputy director for VNIIAES-NTP, the company’s NPP resources director Vladimir Potapov noted.

As a result of the examination, the experts have confirmed that the welding of the main circulation line at the power block No.1 complies with the specification and that the control system in place also functions decently.

The Leningrad NPP is an affiliate company for Rosenergoatom Concern OJSC. The plant is based in the city of Sosnovy Bor, 40 km to the west from Saint Petersburg at the Gulf of Finland shore. The Leningrad NPP is the first Russian nuclear power plant having RBMK-1000 reactors (uranium-graphite channel-type thermal neutron reactors). The NPP exploits 4 power blocks with the electric capacity of 1000 megawatt each. Also, pursuant to the NPP-2006 project, 1,2 VVER-1200 power blocks included into The State Atomic Energy Corporation ROSATOM long-term plan are being constructed. Rosenergoatom Concern OJSC is the owner and developer of the project. Holding TITAN-2 is the primary contractor. ATOMPROEKT is the general designer.

The Leningrad NPP Information and Public Relations Administration.