Izvestia Vysshikh Uchebnykh Zawedeniy. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Results of a preoperational inspection at unit №1 of Novovoronezh NPP II

10/02/2017 2017 - #03 Nuclear power plants

Urazov O.V.

DOI: https://doi.org/10.26583/npe.2017.3.13

UDC: 621.311.25

A preoperational inspection for the state of the parent metal and welded joints in components and pipelines at unit № 1 of Novovoronezh NPP II is discussed. Peculiarities involved in the inspection of the reactor vessel welded joints facing the anticorrosive plating and the steam generator heatexchange tubes using innovative test systems and techniques are considered.

To inspect the reactor vessel, «Computational and Engineering Case Study RTO-KR-UZA-15-[1] was developed specifically, based on which the VVER-1200 reactor vessel welded joints were inspected, using a manual ultrasonic technique, through the anticorrosive plating.

A technology [2], developed by JSC «Center for Eddy-Current Testing «Politest» and by the Scientific and Technical Center for Emergency Engineering Operations at Nuclear Power Plants, a branch of JSC «Concern Rosenergoatom», and used for the first time at a Russian NPPs at the stage of preoperational incoming inspection for the state of the parent metal and welded joints in components and pipelines at unit № 1 of Novovoronezh NPP II using «Politest-PG», an innovative system for the automated eddy-current testingof the steam generator heat-exchange tubes at nuclear power plants with VVER reactors, was used to inspect the heat-exchange tubes in all of the steam generators. As a result of the test, the steam generator tubes were found to have discontinuities with the maximum depth of up to 10% of the nominal wall thickness which is tolerable. The inspection results have confirmed the unit to be fit for commercial operation.

References

  1. Technical Basis RTO-KR-UZK-15, issued 02.11.2015. Moscow. JSC «NIKIMT-Atomstroy» Publ., 2015. 50 p. (in Russian).
  2. ATPP-15-2011. Standard Program for Preoperational Inspection of Base Metal and Welded Connections in Components and Pipelines of Security-Related Systems at NPPs with VVER-1200 Reactors. Moscow. JSC «Concern Rosenergoatom» Publ., 2011. 102 p. (in Russian).
  3. GOST 27.002-2015. Industrial product dependability. Terms and definitions. Moscow. Standartinform Publ., 2016. 28 p. (in Russian).
  4. Ul’trazvuk. Malen’kaya entsiklopediya. [Ultrasound. A small encyclopaedia.] Moscow. Sovetskaya entsiklopediya Publ., 1979. 400 p. (in Russian).
  5. Statnikov E.Sh., Muktepavel V.O. Tekhnologiya ultrazvukovoi udarnoi obrabotki kak sredstvo povyshennoi nadezhnosti i dolgovechnosti svarnykh metallokonstruktsij. [Ultrasonic impact treatment as a method for improving reliability and durability of welded metal structures]. Svarochnoe proizvodstvo. 2003, iss. 4, pp. 25-29 (in Russian).
  6. Marushchak P.O., Salo U.V., Bishchak R.T., Poberezhnyi L.Ya. Study of Main Gas Pipeline Steel Strain Hardening After Prolonged Operation. Chemical and Petroleum Engineering. 2014, v. 50, iss. 1-2, pp. 58-61.
  7. Pleshanov V.S., Kibitkin V.V., Panin V.E. Mesomechanics and Fatigue Fracture for polycrystals with macroconcentratrs. Theoretical and Applied Fracture Mechanics. 1998, v. 30, no. 1, pp. 13-18.
  8. Blaha F., Langenecker B. Plastitatsuntersuchungen von Menallkristallen in Ultraschallfeld. Naturwis. 1955, v. 20, no. 9, p. 556 (in German).
  9. Resolution No. NVOAES-21R-368K(04-03)-2015, issued 25.06.2015 Moscow. JSC «Concern Rosenergoatom» Publ., 2015. 8 p. (in Russian).
  10. Minin S.I., Trofimov A.I., Trofimov M.A. Tekhnologiya termicheskoj svarki tsirkulyatsionnykh truboprovodov AES s vozdeistviem ul’trazvuka. [Heat welding of NPP circulation pipelines with ultrasonification]. Izvestiya vuzov. Yadernaya energetika. 2016, no. 4, pp. 5-11 (in Russian).
  11. Abramov O.V.Kristallizatsiya metallov v ul’trazvukovom pole [Crystallisation of metals in ultrasonic field]. Мoscow. Metallurgiya Publ., 1972. 256 p. (in Russian).
  12. Kulemin A.V. Ul’trazvuk i diffuziya v metallakh [Ultrasound and diffusion in metals]. Moscow. Mashinostroenie Publ., 1978. 200 p. (in Russian).
  13. PNAE G-7-030-91. Unifitsirovannye metodiki nerazrushaiushchego kontrolia osnovnykh materialov (polufabrikatov), svarnykh soedinenij i naplavki oborudovaniya i truboprovodov AEU. Ultrazvukovoj control’. Chast’ 2. Kontrol’ svarnykh soedinenij i naplavki [Unified methods of non-destructive examination of the main materials (semi-finished items), weld joints and seams of nuclear power unit equipment and pipelines. Ultrasonic examination. Part 2. Examination of weld joints and seams.] Moscow. TsNIIAtominform, 1992. 157 p. (in Russian).
  14. Sagalevich V.M. Metody ustraneniya svarochnykh deformatsij i napryazhenij [Methods for correcting welding deformations and stress]. Moscow. Mashinostroenie Publ., 1974. 248 p. (in Russian).
  15. Minin S.I., Trofimov A.I., Trofimov M.A. Avtomatizirovannaya ul’trazvukovaya sistema snyatiya ostatochnykh napryazhenij v svarnykh soedineniyakh tsirkuliatsionnykh truboprovodov AES [The automatic ultrasonic system for residual stress removal in NPP circulation pipeline weld joints]. Izvestiya vuzov. Yadernaya energetika. 2016, no. 3, pp. 13-19 (in Russian).
  16. MT 1.2.1.15.001.0206-2014. Sistema avtomatizirovannogo vikhretokovogo kontrolya teploobmennykh trub parogeneratorov atomnykh stantsij s reaktornymi ustanovkami tipa VVER «Politest-PG». Metodika kontrolya [Automated eddy current testing system for steam generator heat-exchange pipes at nuclear power plants with VVER-type reactors «Polytest-PG». Testing procedure.] Moscow. JSC «Concern Rosenergoatom» Publ., 2014. 77 p. (in Russian).
  17. PT 61.00.00.00.00.00.RO2. Programma analiza dannykh vikhretokovogo kontrolya «PEGAS». Rukovodstvo operatora [«PEGAS» code for eddy current testing data analysis. The operator’s manual.] Moscow. LLC «Center for eddy current control’ POLITEST» Publ., 2012. 110 p. (in Russian).
  18. Antonov A.V., Chepurko V.A. Statisticheskij analiz dannykh ob otkazakh oborudovaniya atomnykh stantsij v usloviyakh neodnorodnogo potoka sobytij [Statistical analysis of data on nuclear power plant equipment failures in the context of non-uniform event stream]. Izvestiya vuzov. Yadernaya energetika. 2016, no. 3. pp. 20-27 (in Russian).
  19. Finkelstein M. Failure rate modeling for reliability and risk. Verlag. London Limited: Springer, 2008. 290 p.

preoperational inspection ultrasonic testing ultrasonic testing technology eddy-current testing reactor vessel steam generator