On the example of plate bimetallic R-301 reactor manufactured of structural steel with the wall thickness of 130 mm and the plate from stainless heat-proof steel, the phenomenon was studied concerning the effect of the operation in the hydrogen-containing environment on the size and speed of intergranular embrittlement development. For assessment of influence of the operational factors on the base metal state of the reactor the selection of microprobes of the structure external wall by mechanical way without thermal effect on metal has been made. Besides, macro-sample was selected with a diameter of 22 mm and 80 mm in depth in the lower head of the vessel (part of structure with the highest temperature of operation) with the use of a hole saw.
Research of the macro-sample metal included: determination of chemical composition, assessment of mechanical properties and impact strength, carrying out of metallographic, durometric and electron fractographic analysis. Essential changes in the structure and mechanical properties of the base metal, including in the zone of adjoining to the plate of R-301 reactor, were not found.
For identification of the degree of intergranular embrittlement of the reactor base metal the electronic fractographic analysis of fractures according to the current standard documentation was conducted. It is found that steel 12XM in the process of operation was subjected to low degree of hydrogen embrittlement..
The proposed methods of diagnostics of the type, degree and speed of damaging of two-layer reactor wall metal allow to carry out an assessment of the actual technical condition of metal case ensuring high economic effect.
V.M. Goritskiy, Dr. Sci. (Eng.), Head of the Department, email@example.com G.R. Shneyderov, Cand. Sci. (Eng.), Head of Laboratory ZAO TSNIIPSK named after Melnikov, Moscow, Russia P.R. Nechiporenko, Head of Laboratory OOO INTERYUNIS, Moscow, Russia O.V. Gorchakov, Development Deputy Director AO VNIKTIneftekhimoborudovaniye, Volgograd, Russia
1. Goritskiy V.M. Diagnostika metallov (Metal Diagnostics). Moscow: Metallurgizdat, 2004. 273 p.
2. Nelson G.G. Okhrupchivanie konstruktsionnykh staley i splavov (Embrittlement of Structural Steels and Alloys). Moscow: Metallurgiya, 1988. 552 p.
3. Glikman E.E., Bruver R.E., Krasnov A.A., Trubin S.V. Mechanism of «spontaneous» origination of microcracks on the borders of grains and embrittlement of solid Fe-P solutions. Physics of metals and metal science. 1980. Iss. 50. № 4. pp. 861–871.
4. RD 03-421—01. Metodicheskie ukazaniya po provedeniyu diagnostirovaniya tekhnicheskogo sostoyaniya i opredeleniyu ostatochnogo sroka sluzhby sosudov i apparatov (RD 03-421—01. Methodical guidelines on carrying out diagnostics of technical condition and identification of the residual service life of vessels and equipment). Available at: http://docs.cntd.ru/document/1200030798 (accessed: January 15, 2017).
5. RD 03-410—01. Instruktsiya po provedeniyu kompleksnogo tekhnicheskogo osvidetelstvovaniya izotermicheskikh rezervuarov szhizhennykh gazov (RD 03-410—01. Instruction for carrying out the comprehensive technical examination of the liquefied gases isothermal tanks). Available at: http://docs.cntd.ru/document/1200026047 (accessed: January 17, 2017).
6. Raschety i ispytaniya na prochnost v mashinostroenii. Metody issledovaniya izlomov metallov (Calculations and strength tests in mechanical engineering. Research methods of metal fractures). Moscow: VNIINmash, 1979. 51 p.
7. MR 5—81. Raschety na prochnost v mashinostroenii. Fraktograficheskiy metod opredeleniya kriticheskoy temperatury khrupkosti metallicheskikh materialov (MR 5—81. Strength calculations in mechanical engineering. Fractographic method of identification of critical temperature of metal materials embrittlement). Moscow: VNIINmash, 1981. 23 p.
8. Archakov Yu.I. Vodorodnaya korroziya stali (Hydrogen Corrosion of Steel). Moscow: Metallurgiya, 1985. 192 p.