1. 08/2007 1 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Post Mortem Investigations of the NPP Greifswald WWER-440 Reactor Pressure Vessels Hans-Werner Viehrig, Udo Rindelhardt and Jan Schuhknecht Forschungszentrum Dresden-Rossendorf e.V. Institute for Safety Research P.O.Box 510119 01314 Dresden, Germany 19th International Conference on Structural Mechanics in Reactor Technology August 12 – 17, Toronto, Canada

2. 08/2007 2 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Outline Introduction Trepanning of the Greifswald WWER-440 (230) Reactor Pressure Vessels (RPV) Material and Specimens Testing and Evaluation Test Results of the RPV Core Welding Seam Summary and Conclusions

3. 08/2007 3 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Introduction NPP North Greifswald located at the Baltic Sea in the north eastern part of Germany 4 Units WWER-440 (230) operated from 1974 to 1990 4 Units WWER-440 (213) were under construction

4. 08/2007 4 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community unitcyclesoperation period effective days annealed in azimuthal maximum of  E>1MeV in units of 10 19 n/cm 2 inner wall axial maximum inner wall weld 4 outer wall axial maximum outer wall weld 4 1151974-19884205.019883.82.60.700.38 1*21988-1990627.4-0.080.070.0170.012 2141975-19904067.419905.34.10.830.60 3121978-19903581.819904.43.40.680.50 4111979-19903207.9not4.03.10.620.45 Operation Characteristics and Expected Maximum Neutron Fluencies of Greifswald WWER-440 (230) Units 1 to 4 * re-irradiated water inlet temperature: 265°C recovery annealing: 475°C/152h

5. 08/2007 5 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Trepanning of the Greifswald WWER-440 (230) Reactor Pressure Vessels (RPV) milling head lead plug marker extractor fan Trepanning Device

6. 08/2007 6 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Location of the Trepanning Device at the RPV

7. 08/2007 7 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community RPV Steels, Irradiation and Annealing Conditions of the Trepans Sampled from Greifswald Unit 1 trepanRPV-Materialcondition RPV-wall inside Fluence in 10 19 n/cm 2 (E>0.5 MeV) temperature during recovery annealing in °C 1-1.1weld metal SN0.1.4.IAI4.05475 1-1.2weld metal SN0.1.4.IAI4.05475 1-1.5weld metal SN0.1.4.IAI4.05475 1-1.4base metal shell 0.3.1.IAI5.19475 1-1.3base metal shell 0.3.1.U>0.11<300 I: irradiated A: recovery annealed U: unirradiated reactor core 1-1.3 1-1.4 1-1.1 1-1.2 1-1.5

8. 08/2007 8 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Chemical Composition in mass % Unit/ Trepan materialCSiMnPSCrNiMoCuVRef. %%%%% 1weld SN0.1.40.050.471.220.0370.0121.480.230.410.1030.16[1] 1-1 *1 weld SN0.1.41.100.0441.480.250.390.1250.13[2] 1-1 *2 weld SN0.1.40.900.0281.470.230.420.1410.11[2] 1shell 0310.190.310.440.0150.0162.980.180.670.1800.30[1] 1-1 *1 shell 0310.420.0112.920.180.650.26[2] *1 inner RPV wall *2 110 from the inner RPV wall [1] mean values from TACIS Report [2] measured (wet chemistry) on trepan 1.1

9. 08/2007 9 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Handling of the Trepans within the Hot Cell

10. 08/2007 10 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Welding Seam SN0.1.4. over the RPV Wall Longitudinal Section 2.5 mm from the RPV inner wall 103.5 mm from the RPV inner wall Welding root

11. 08/2007 11 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Trepan 1-1 With the Location of the Welding Seam and Cutting Scheme

12. 08/2007 12 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Orientation of WWER-440 (213) RPV Surveillance Specimens Producer SKODA* Base metal:tensile specimens:L Charpy-V and COD:LT weld metal:tensile specimens :L Charpy-V and COD:TL HAZ:tensile specimens :T Charpy-V and COD:TS Producer Russia** base metal:tensile specimens :L Charpy-V and COD:LS weld metal:tensile specimens :L Charpy-V and COD:TS HAZ:tensile specimens :T Charpy-V and COD:TS * Information Dr. Brynda SKODA Nuclear ** Information D. Erak RRC Kurchatov Institute

13. 08/2007 13 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Orientation of Weld Metal Specimens 5 mm S T SE(B) specimen weld metal TL

14. 08/2007 14 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Location of the Investigated Discs Within Trepan 1-1, Neutron Fluences, MC Test Results According to ASTM E1921-05 and Charpy-V Parameter code disc distance from inner surface (centre disc) neutron fluence in 10 18 n/cm 2 (E>1MeV) ASTM E1921 - 05SINTAPCharpy-V before*after*totalT0T0 σT 0 T 0 SINTAP TT 41J USE mm°CK J 1-1.18.324.230.7124.9310.36.432.551.4130.8 1-1.321.921.470.6422.1149.16.349.132.6153.4 1-1.642.316.890.5117.40-5.06.4-5.0 1-1.969.911.630.3611.99-40.76.4-13.6 1-1.1293.88.210.268.4719.86.340.920.1120.3 SE(B) specimen orientation: TS * Recovery annealing

15. 08/2007 15 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community K Jc Values Measured on Charpy Size SE(B) Specimens Versus the Test Temperatures Normalised to T 0 of the Individual Discs, and Master Curves

16. 08/2007 16 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Location of the Investigated Discs Within Trepan 1-1, Neutron Fluences, MC Test Results According to ASTM E1921-05 and Charpy-V Parameter code disc distance from inner surface (centre disc) neutron fluence in 10 18 n/cm 2 (E>1MeV) ASTM E1921 - 05SINTAPCharpy-V before*after*totalT0T0 σT 0 T 0 SINTAP TT 41J USE mm°CK J 1-1.18.324.230.7124.9310.36.432.551.4130.8 1-1.321.921.470.6422.1149.16.349.132.6153.4 1-1.642.316.890.5117.40-5.06.4-5.0 1-1.969.911.630.3611.99-40.76.4-13.6 1-1.1293.88.210.268.4719.86.340.920.1120.3 SE(B) specimen orientation: TS * Recovery annealing SINTAP – Structural Integrity Assessment Procedures for European Industry

17. 08/2007 17 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Course of the Reference Temperatures T 0 and T 0 SINTAP Through the Welding Seam SN0.1.4.

18. 08/2007 18 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Location of the Investigated Discs Within Trepan 1-1, Neutron Fluences, MC Test Results According to ASTM E1921-05 and Charpy-V Parameter code disc distance from inner surface (centre disc) neutron fluence in 10 18 n/cm 2 (E>1MeV) ASTM E1921 - 05SINTAPCharpy-V before*after*totalT0T0 σT 0 T 0 SINTAP TT 41J USE mm°CK J 1-1.18.324.230.7124.9310.36.432.551.4130.8 1-1.321.921.470.6422.1149.16.349.132.6153.4 1-1.642.316.890.5117.40-5.06.4-5.0 1-1.969.911.630.3611.99-40.76.4-13.6 1-1.1293.88.210.268.4719.86.340.920.1120.3 SE(B) specimen orientation: TS * Recovery annealing

19. 08/2007 19 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community K Jc(1T) values versus the test temperature normalised to RTT 0 of the different discs of trepan 1-1 and VERLIFE lower bound curve VERLIFE – Unified Procedure for Lifetime Assessment of Components and Piping in WWER NPP’s

20. 08/2007 20 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community K Jc(1T) values versus the test temperature normalised to RTT 0 (SINTAP) of the different discs of trepan 1-1 and VERLIFE lower bound curve

21. 08/2007 21 Institute for Safety Research Hans-Werner Viehrig Member of the Leibniz Community Summary and Conclusions -The recovery annealing could be confirmed with the test results. -K Jc values generally follow the course of the MC with a remarkable scatter. -There is a big variation of the evaluated T 0 through the thickness of the RPV wall. -The highest T 0 was about 50°C at a distance of 22 mm from the inner surface of the weld. It is 40 K higher compared with T 0 at the inner surface. -The measured K Jc values are not enveloped by the RTT 0 indexed VERLIFE lower bound curve. However, the VERLIFE lower bound curve indexed with the SINTAP reference temperature RTT 0 SINTAP envelops the K Jc values. Trepans were taken from the core weld SN0.1.4 and base metal of the Greifswald Unit 1 RPV. Charpy size SE(B) specimens from 5 locations through the thickness of the welding seam were tested and evaluated according to the MC approach as adopted in ASTM E1921-05. Results of the welding seam SN0.1.4. (trepan 1-1) in the irradiated, recovery annealed and re- irradiated condition: