It is known, safety and survivability, serviceability of the equipment is regulated durability by characteristics of his separate units and elements in which there can be initial or operational defects such as superficial different orientation semi elliptical superficial inclined cracks. Numerical methods of calculation allow expanding reliability of received results on the set algorithms of calculation of corresponding models of destruction. Change of a kind of tensely-deformed conditions near to a contour of cracks, at transition from deeper points, to superficial, depends on constraint of deformations along their front. On the basis of experimental results and numerical decisions, diagnostics change of the form defects such as superficial inclined semi elliptical cracks low-cycle cracks is stated. The data of certainly - element modeling are realized on the basis of macro owls of program complex ANSYS. Law of an orientation of development elastoplastic destructions is investigated at low-cycle destruction.

On the basis of deformation criterion of destruction, settlement - experimental, numerical and analytical methods with application of mathematical model of spatial distribution of mechanical properties, settlement - experimental kinetic dependences and critical parameters elastic-plastic destructions for developing inclined superficial low-cycle semi-elliptical cracks in corresponding zones of welded connection are received. And also, methodological positions of limiting conditions of elements of the responsible equipment of the oil, oil-and-gas and petrochemical industry, aviation, space, nuclear and thermal technical equipment from non-uniform metal materials are formulated under nonlinear conditions loading and general methodology of carrying out more exact calculation of durability, survivability and an operational resource at presence in them of defects such as cracks in a wide range of temperature and design features.

References

1. Makhutov N.A., Konstruktsionnaya prochnostʹ, resurs i tekhnogennaya bezopasnostʹ (Structural strength, life and man-made safety), Novosibirsk: Nauka Publ., 2005.

2. Makhutov N.A., Makarenko I.V., Makarenko L.V., Analysis and simulation of kinetics of elasto-plastic weld failure in structures at cryogenic temperatures, IOP Conference Series Materials Sci-ence and Engineering, 2019, doi:10.1088/1757-899X/681/1/012030

3. Makhutov N.A., Makarenko I.V., Makarenko L.V., Study of the spatial mechanical inhomogeneity of welded joints of austenitic stainless steels (In Russ.), Zavodskaya laboratoriya, 2004, V. 70, no. 2, pp. 39–49.

4. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics of the multidirectionality of elastic-plastic fracture with allowance for anisotropy of the material properties (In Russ.), Zavodskaya la-boratoriya. Diagnostika materialov, 2020, V. 86, no. 1, pp. 44–50.

5. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics of residual stress fields in inhomoge-neous austenitic steels under elastoplastic deformation (In Russ.), Zavodskaya laboratoriya, 1999, V. 65, no. 4, pp. 40–44.

6. Makhutov N.A., Makarenko I.V., Makarenko L.V., Influence of anisotropy of physical and me-chanical properties on the kinetics of cracks in austenitic steels (In Russ.), Problemy prochnosti, 2004, no. 1, pp. 113–119.

7. ANSYS, 2010. Structural Analysis Guide. 660578.

8. Azuma K., Li Y, Hasegawa K., Evaluation of stress intensity factor interactions between adjacent flaws with large aspect ratios, Proceedings of the ASME pressure vessels and piping conference, 2015, Article no. 45063.

9. Li C.Q., Fu G.Y., Yang W., Stress intensity factors for inclined external surface cracks in pressur-ized pipes, Eng. Fract. Mech., 2016, V. 165, pp. 72–86.

10. Fu G.Y., Yang W., Li C.Q., Stress intensity factors for mixed mode fracture induced by inclined cracks in pipes under axial tension and bending, Theoretical and Applied Fracture Mechanics, 2017, V. 89, pp. 100 - 109.

11. Panasyuk V.V., Mekhanika kvazikhrupkogo razrusheniya materialov (Mechanics of quasi-brittle fracture of materials), Kiev: Naukova dumka Publ., 1990, 415 p.

12. Panasyuk V.V., Predel'noe ravnovesie khrupkikh tel s treshchinami (Limiting equilibrium of brit-tle bodies with cracks), Kiev: Naukova dumka Publ., 1974, 416 p.

13. Morozov E.M., Raschet na prochnost' pri nalichii treshchin (Strength calculation in the presence of cracks), In: Prochnost' materialov i konstruktsiy (Strength of materials and structures), Kiev: Nau-kova dumka Publ., 1975, pp. 323–333.

14. Makhutov N.A., Makarenko I.V., Makarenko L.V., Studies on the fracture mechanism and kinet-ics of randomly oriented surface semielliptic cracks at the multiaxial stress-strain state with defor-mation criteria of nonlinear fracture mechanics (In Russ.), Problemy prochnosti, 2013, no. 4(424), pp. 91–97.

15. Makhutov N.A., Makarenko I.V., Makarenko L.V., Studies on the fracture mechanism and kinet-ics of randomly oriented surface semielliptic cracks at the multiaxial stress-strain state with defor-mation criteria of nonlinear fracture mechanics, Strength of Materials, 2013, V. 45, no. 4, pp. 454–458.

16. Makhutov N.A., Makarenko I.V., Makarenko L.V., Numerical and experimental study of devel-oping semi-elliptical inclined low-cycle surface cracks (In Russ.), Zavodskaya laboratoriya. Diag-nostika materialov, 2013, no. 11, V. 79, pp. 39–44.

17. Makhutov N.A., Makarenko I.V., Makarenko L.V., Tensely - deformed conditions in conditions of complex circuits loading and non-uniform properties at top of the crack, Abstract of 5-th Interna-tional Conference “Problems of dynamics and strength in gas-turbine construction”: edited by Zinkovskyy A.P., Kyiv, 27-31 May 2014, Kyiv: Publ. of G.S. Pisarenko Institute for Problems of Strength of the National Ac. Sci. of Ukraine, 2014, pp. 159–160.

18. Makhutov N.A., Makarenko I.V., Makarenko L.V., Calculation and experimental analysis of the stress-strain state for in clined semi-elliptical surface cracks, Inorganic Materials, 2017, V. 53, no. 15, pp. 1502–1505.

19. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics analysis and orientation of elastic-plastic deformation and fracture (In Russ.), Zavodskaya laboratoriya. Diagnostika materialov, 2019, no. 6, V. 85, pp. 47–52.

20. Vyatkin V.V., Khabidenov S.O., Toropov E.S., Opyt i perspektivy primeneniya trub s vnutrennim antikorrozionnym pokrytiem dlya truboprovodnykh sistem (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 6, pp. 90-92, DOI:10.24887/0028-2448-2020-6-90-92

21. Fu G.Y., Yang W., Li C.Q., Stress intensity factors for mixed mode fracture induced by inclined cracks in pipes under axial tension and bending, Theoret. Appl. Fract. Mech., 2017, V. 89, pp. 100–9.

It is known, safety and survivability, serviceability of the equipment is regulated durability by characteristics of his separate units and elements in which there can be initial or operational defects such as superficial different orientation semi elliptical superficial inclined cracks. Numerical methods of calculation allow expanding reliability of received results on the set algorithms of calculation of corresponding models of destruction. Change of a kind of tensely-deformed conditions near to a contour of cracks, at transition from deeper points, to superficial, depends on constraint of deformations along their front. On the basis of experimental results and numerical decisions, diagnostics change of the form defects such as superficial inclined semi elliptical cracks low-cycle cracks is stated. The data of certainly - element modeling are realized on the basis of macro owls of program complex ANSYS. Law of an orientation of development elastoplastic destructions is investigated at low-cycle destruction.

On the basis of deformation criterion of destruction, settlement - experimental, numerical and analytical methods with application of mathematical model of spatial distribution of mechanical properties, settlement - experimental kinetic dependences and critical parameters elastic-plastic destructions for developing inclined superficial low-cycle semi-elliptical cracks in corresponding zones of welded connection are received. And also, methodological positions of limiting conditions of elements of the responsible equipment of the oil, oil-and-gas and petrochemical industry, aviation, space, nuclear and thermal technical equipment from non-uniform metal materials are formulated under nonlinear conditions loading and general methodology of carrying out more exact calculation of durability, survivability and an operational resource at presence in them of defects such as cracks in a wide range of temperature and design features.

References

1. Makhutov N.A., Konstruktsionnaya prochnostʹ, resurs i tekhnogennaya bezopasnostʹ (Structural strength, life and man-made safety), Novosibirsk: Nauka Publ., 2005.

2. Makhutov N.A., Makarenko I.V., Makarenko L.V., Analysis and simulation of kinetics of elasto-plastic weld failure in structures at cryogenic temperatures, IOP Conference Series Materials Sci-ence and Engineering, 2019, doi:10.1088/1757-899X/681/1/012030

3. Makhutov N.A., Makarenko I.V., Makarenko L.V., Study of the spatial mechanical inhomogeneity of welded joints of austenitic stainless steels (In Russ.), Zavodskaya laboratoriya, 2004, V. 70, no. 2, pp. 39–49.

4. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics of the multidirectionality of elastic-plastic fracture with allowance for anisotropy of the material properties (In Russ.), Zavodskaya la-boratoriya. Diagnostika materialov, 2020, V. 86, no. 1, pp. 44–50.

5. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics of residual stress fields in inhomoge-neous austenitic steels under elastoplastic deformation (In Russ.), Zavodskaya laboratoriya, 1999, V. 65, no. 4, pp. 40–44.

6. Makhutov N.A., Makarenko I.V., Makarenko L.V., Influence of anisotropy of physical and me-chanical properties on the kinetics of cracks in austenitic steels (In Russ.), Problemy prochnosti, 2004, no. 1, pp. 113–119.

7. ANSYS, 2010. Structural Analysis Guide. 660578.

8. Azuma K., Li Y, Hasegawa K., Evaluation of stress intensity factor interactions between adjacent flaws with large aspect ratios, Proceedings of the ASME pressure vessels and piping conference, 2015, Article no. 45063.

9. Li C.Q., Fu G.Y., Yang W., Stress intensity factors for inclined external surface cracks in pressur-ized pipes, Eng. Fract. Mech., 2016, V. 165, pp. 72–86.

10. Fu G.Y., Yang W., Li C.Q., Stress intensity factors for mixed mode fracture induced by inclined cracks in pipes under axial tension and bending, Theoretical and Applied Fracture Mechanics, 2017, V. 89, pp. 100 - 109.

11. Panasyuk V.V., Mekhanika kvazikhrupkogo razrusheniya materialov (Mechanics of quasi-brittle fracture of materials), Kiev: Naukova dumka Publ., 1990, 415 p.

12. Panasyuk V.V., Predel'noe ravnovesie khrupkikh tel s treshchinami (Limiting equilibrium of brit-tle bodies with cracks), Kiev: Naukova dumka Publ., 1974, 416 p.

13. Morozov E.M., Raschet na prochnost' pri nalichii treshchin (Strength calculation in the presence of cracks), In: Prochnost' materialov i konstruktsiy (Strength of materials and structures), Kiev: Nau-kova dumka Publ., 1975, pp. 323–333.

14. Makhutov N.A., Makarenko I.V., Makarenko L.V., Studies on the fracture mechanism and kinet-ics of randomly oriented surface semielliptic cracks at the multiaxial stress-strain state with defor-mation criteria of nonlinear fracture mechanics (In Russ.), Problemy prochnosti, 2013, no. 4(424), pp. 91–97.

15. Makhutov N.A., Makarenko I.V., Makarenko L.V., Studies on the fracture mechanism and kinet-ics of randomly oriented surface semielliptic cracks at the multiaxial stress-strain state with defor-mation criteria of nonlinear fracture mechanics, Strength of Materials, 2013, V. 45, no. 4, pp. 454–458.

16. Makhutov N.A., Makarenko I.V., Makarenko L.V., Numerical and experimental study of devel-oping semi-elliptical inclined low-cycle surface cracks (In Russ.), Zavodskaya laboratoriya. Diag-nostika materialov, 2013, no. 11, V. 79, pp. 39–44.

17. Makhutov N.A., Makarenko I.V., Makarenko L.V., Tensely - deformed conditions in conditions of complex circuits loading and non-uniform properties at top of the crack, Abstract of 5-th Interna-tional Conference “Problems of dynamics and strength in gas-turbine construction”: edited by Zinkovskyy A.P., Kyiv, 27-31 May 2014, Kyiv: Publ. of G.S. Pisarenko Institute for Problems of Strength of the National Ac. Sci. of Ukraine, 2014, pp. 159–160.

18. Makhutov N.A., Makarenko I.V., Makarenko L.V., Calculation and experimental analysis of the stress-strain state for in clined semi-elliptical surface cracks, Inorganic Materials, 2017, V. 53, no. 15, pp. 1502–1505.

19. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics analysis and orientation of elastic-plastic deformation and fracture (In Russ.), Zavodskaya laboratoriya. Diagnostika materialov, 2019, no. 6, V. 85, pp. 47–52.

20. Vyatkin V.V., Khabidenov S.O., Toropov E.S., Opyt i perspektivy primeneniya trub s vnutrennim antikorrozionnym pokrytiem dlya truboprovodnykh sistem (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 6, pp. 90-92, DOI:10.24887/0028-2448-2020-6-90-92

21. Fu G.Y., Yang W., Li C.Q., Stress intensity factors for mixed mode fracture induced by inclined cracks in pipes under axial tension and bending, Theoret. Appl. Fract. Mech., 2017, V. 89, pp. 100–9.