BELENE NPP Reactor plant V-466B

BELENE NPP Reactor plant V-466B FSUEOKB «GIDROPRESS» Ryzhov S.B., Ermakov D.N., Repin A.I. May, 2008

FSUE OKB "GIDROPRESS" • Federal State Unitary Enterprise, Experimental and Design organization “Gidropress”, as the General design organization for reactor plants, is engaged in development of designs of equipment and systems, intended for power engineering and nuclear engineering for more than half a century. • Using projects, developed by OKB “Gidropress” more 85 reactor plants of different types have been constructed. • Our designs have been implemented at the nuclear power facilities in Russia, Bulgaria, Ukraine, Czech Republic, Finland, Germany, Hungary, Slovakia, Armenia,China, India.

Advanced reactor plant VVER-1000(V-466B) Since the moment of RP V-320 development the successful progress has been made for the concept of RP VVER-1000. There were developed the designs of RP V-392 for A-92 NPP(of improved safety), RP V-428 (in operation in China), RP V-412 (under implementation in India). A number of design improvements have been made in the above-mentioned projects concerning equipment and systems that facilitated reaching the safety level that meets the up-to-date NEC and international requirements and IAEA recommendations In 2004-2006 there was performed an assessment ofAES-92 projectconcerning EUR requirements of revision С. Assessments were performed by westernexperts with participation ofproject designers. As a result of this worka good conformity of the project with the specified requirements was determined

Basic Changes in the Design (1) • advanced reactor (service life-60 years). • up-to-date fuel cycle on the basis of usage of fuel assemblies (FA-A or FA-2) with uranium-gadolinium fuel of latest modifications providing high fuel burnup; • application of new SGs (service life-up to 60 years) • application of new Reactor coolant pumps • application of new CPS drives ShEM-3 • implementation of additional passive safety systems • corium localization device (core-catcher) and changes in arrangement of the reactor pit equipment and in design of some of its components • Design RP main equipment service life - 60 years

Basic Changes in the Design (2) • application of up-to-date digital I&C (including latest modifications of Monitoring Control and Diagnostic System (MCDS), neutron flux monitoring equipment (NFME), Control and Protection System (CPS), emergency level gauge); • implementation of PRZ PORV control procedure under beyond design basis accidents (implementation of feed and bleed procedure); • using of up-to-date automatic systems for RP main equipment inspection; • justification of “leak-before-break” concept for the main RP pipelines and application of the required leak detection systems; • usage of removable modular thermal insulation;

Basic Changes in the Design (3) • implementation of up-to-date surveillance programme with placing the surveillance specimens on the reactor vessel; • extension of the operation period of RP main equipment between technical inspections • using of fuel handling machine with the increased rates of FA horizontal and vertical motion; • using of sipping method in performing check of leak tightness of fuel rod claddings with keeping the traditional method of leak check of claddings • using the reactor main joint power nut driver with simultaneous elongation of all studs, as well as of nut drivers for detachable joints of steam generators, pressurizer, ECCS accumulators • ; • ;

Arrangement of Reactor in Concrete Pit

Advanced Reactor

Advanced Reactor The improvements include: • lengthening the advanced reactor vessel by 300 mm at the expense of lengthening the supporting shell; • increase in the number of CPS CRs; • increase of diameter of reactor vessel; • using the CPS drive ShEM-3; • completely new surveillance programme (arrangement of the irradiated surveillance specimens directly on RPV wall • limitation of nickel content in welds and of harmful impurities in base metal and welds • reducing Тко of nozzles zone shells to minus 35оС

CPS drive ShEM-3

CPS drive ShEM-3 • power electromagnetic system is optimized and dynamic drive characteristic is improved under motion conditions • drive service life (mechanical part) is extended up to 40 years whereas the prototype mechanical part has a service life of 20 years, service life of electromagnets – 10 years and that of position indicator – 5 years • pulling force is increased (  twice as much) • PPI is used with indication of pitch position each 20 mm of extension shaft motion (LPI in ShEM drive provides indication of position of extension shaft with 350 mm pitch) • One drive seal (instead of two in prototipe design)

Steam generator (spaced corridor arrangement of tubes)

Steam generator (spaced corridor arrangement of tubes) • increase circulation rate in the tube bundle that will reduce probability of damage of heat exchanging tubes due to decrease in the growth rate of deposits on the heat exchanging tubes and degree of concentration of corrosion-active impurities under them • reduce possibility of clogging the intertube space with spalled sludge • make easy access into intertube space for inspection of heat exchanging tubes and their cleaning in necessity • increase water inventory in steam generator • enlarge the space under the tube bundle for easy removal of the sludge • Drop ofCoolant headers stress; • Improvement of SG heat exchanging tubes manufacturability and maintainability

Reactor Coolant Pump Set

Reactor Coolant Pump Set • main thrust bearing with water cooling and lubricant • double-speed electric motor, that reduces loads to transformer during startup (this provides the possibility of stepwise startup) • seal, which is capable to provide non-exceeding of nominal leakage (50 L/h) during RCP set trip without cooling for 24 hours at nominal parameters of the primary circuit

Main Reactor Plants Data Comparison

Conclusion • RP design meets the up-to-date requirements and can be licensed for construction

BELENE NPP Reactor plant V-466B