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.
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