The possibilities of contemporary reactor pressure vessel (RPV) fabrication techniques were taken into account while choosing the reactor capacity. Due to the extreme weight of RPV ingots and the technique of their fabrication, the external RPV diameter should be less than 5 m. The RPV’s height is 23500 mm, its external diameter is 4780 mm and its wall thickness is 330 mm. The electrical power of the reactor was found to be 515 MW.

The RPV is made of 15Х2МФА-А steel and the RPV flanges are made of 25ХЗМФА-А steel. The upper part of the RPV has 6 nozzles of 350 mm diameter for the steam outlet, 6 nozzles of 200 mm diameter for the feedwater inlet and other nozzles are of 150 mm diameter.

1.1. Core

The core has 121 shroudless fuel assemblies, being on a spacing of 226 mm 85 fuel assemblies have 18 control absorbing rod clusters and 36 fuel assemblies have burnable poison rods. Fuel assembly has 252 fuel rods arranged on a triangular lattice with 13.5 mm pitch. The fuel rod design is based on the WER-1000 fuel rod design. Stainless steel is expected to be used as the fuel cladding material. The fuel height is 4200 mm.

The results of the V-500 SKDI core neutron calculations are listed in the

table 1.

Main characteristics of V-500 SKDI core

Name, size ______________________________________________________________ Value

1. Core sizes (m)

— equivalent diameter 2.610

— fuel length in cold state 4.200

2. Fuel rod cladding material SS

3. Mean fuel burnup (MW day/kg U) 40

4. Mean volume power density in the core (MW/m^) 68.2

5. Makeup fuel enrichment (%) 3.5

6. Assembly number in the core 121

7. Assembly number with absorber rod 85

8. Mean fertile coefficient 0.78

The steam generator (SG) is a once-through vertical heat exchanging apparatus arranged in the annular space between the RPV and guard tube block shroud. The SG consists of 18 modules which are joined into 6 sections. Each of the sections has an individual steam header and feedwater header, inserted through the RPV nozzles. The SG modules consist of titanium alloy tubes of 10.8 m in length, 12 mm in outer diameter and 1.3 mm in wall thickness, surrounded by a stainless-steel shroud. The guard tube shroud is freely installed on the core support barrel and after removing it from the RPV there is an opportunity to repair or to remove the SG section.

The main technical parameters of V-500 SKDI are listed in Table 2.

Main characteristics of B-500SKDI