Investigation of the causes of crack origination in the inner casing of NK-86 gas turbine engine combustion chamber

Cite item

Full Text


The performance reliability of aerospace products is directly related to the reliability of each essential part; therefore special attention is paid to establishing the reasons of occurrence of defects and to developing preventive measures during the whole life cycle of a product. The article contains the analysis of the results of investigating the causes of defects occurring in the inner casing of the combustion chamber of NK- 86 gas turbine engine «Meridional cracks on the conical part of the flange». Metallurgical properties of the defective casing are examined in detail. A number of studies aimed at determining residual stresses on the surface of a part of the housing, as well as on specimens cut out from the housings with different hours in service and different surface treatment, including the use of additional thermal and mechanical treatment has been carried out. Diagrams of residual stress distribution for the specimens cut out of the housings with different treatment and subjected to various methods of relieving tensile residual stresses are presented. Endurance tests of one of the housings have been carried out. Conclusions about the influence of residual stresses on the fatigue resistance of the parts under investigation have been made. Measures to eliminate and prevent the defect both for the tested housing of the combustion chamber and for the base members manufactured by similar technologies and operated in similar conditions are proposed.

About the authors

Е. Е. Kocherova

Samara State Aerospace University

Author for correspondence.

Postgraduate student of the Department of Strength of Materials

Russian Federation


  1. Normy prochnosti aviatsionnykh gazoturbinnykh dvigateley grazhdanskoy aviatsii [Strength standards for civil aviation gas turbine engines. Moscow: CIAM Publ., 2004. 260 p.
  2. Terent’ev V.F, Petukhov A.N. Ustalost’ vysokoprochnykh metаllicheskikh materialov [Fatigue of high-strength metallic materials]. Moscow: CIAM Publ., 2013. 515 p.
  3. Parton V.Z., Borisovski V.G. Dinamika khrupkogo razrusheniya [Dynamics of brittle fracture]. Moscow: Mashinostroenie Publ., 1988. 240 p.
  4. Anurov U.M., Fedorchenko D.G. Osnovy obespecheniya prochnostnoy nadezhnosti aviatsionnykh dvigateley i silovykh ustanovok [Principles of ensuring strength reliability of aircraft engines and power plants]. St. Petersburg: Peter the Great Saint-Petersburg Рolytechnic University Publ., 2004. 390 p.
  5. Kudryavcev I.V., Naumchenko N.E., Savvina N.M. Ustalost' krupnyh detalej mashin [Fatigue of large machine parts]. Moscow: Mashinostroenie Publ., 1981. 240 p.
  6. Kolmogorov V.L. Napryajeniya, deformatsii, razrusheniya [Stresses, deformations, fracture]. Moscow: Metallurgiya Publ., 1970. 229 p.
  7. Khimushchin F.F. Ligirovanie, termicheskaya obrabotka i svoystva zharoprochnykh staley i splavov [Ligation, thermal treatment and properties of heat-resistant steels and alloys]. Moscow: Metallurgiya, 1969. 749 p.
  8. GOST 25.502-79. Strength analysis and testing in machine building. Methods of metals mechanical testing. Methods of fatigue testing. Moscow: Standartinform Publ., 1983. 50 p. (In Russ.)
  9. Birger I.A. Sterzhni, plastinki, obolochki [Rods, plates, shells]. Moscow: Fizmatlit Publ., 1992. 392 p.
  10. Birger I.A. Ostatochnienapryazheniya [Residual stresses]. Moscow: Mashinostroenie Publ., 1963. 368 p.
  11. Ivanov S.I. The determination of residual stresses in plates by stripes method. Trudy KuAI. Issue 48. Kuibyshev: Kuibyshev Aviation Institute Publ., 1971. P. 139-152. (In Russ.)
  12. Pavlov V.F., Kirpichev V.A., Vakulyuk V.S. Prognozirovanie soprotivleniya ustalosti poverkhnostno-uprochnennykh detaley po ostatochnym napryazheniyam [Prediction of fatigue resistance of surface-hardened parts by residual stresses]. Samara: Samarskiy nauchnyy tsentr Publ., 2012. 125 p.

Supplementary files

Supplementary Files

Copyright (c) 2016 VESTNIK of the Samara State Aerospace University

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies