Research of residual stresses in hardening of drill pipe thread

Set the relationship between the constructive and technological process parameters folding threaded conical surface drill pipe (geometry of a strengthening of the movie, the size of the load, radius of hollow), magnitude and distribution of residual stresses in a threaded surface based on complex mathematical models developed and a series of pilot studies stress-strain state threads and fatigue tests.
Materials and methods
Basic Theory of mechanics of deformation of continuous media, technology engineering, Foundations of the theory of deformation of continuous media, dynamics of machines and mechanisms, theoretical mechanics, modeling techniques of stressed-strained state of the theory of surface plastic deformation. The results of the research were recorded using video and certified modern instruments and measurement tools. Visualization and processing of results of experimental and theoretical research done using interdisciplinary engineering packages on high-performance computing complex software systems using ANSYS, ABAQUS, and developed a computer program PKNM Deep Roll Thread v1.0.
Results
As a result of research and experience in strengthening the main thread patterns and the relationship between reinforcement and quality parameters of the surface layer, the methodology of static and dynamic mathematical modeling and practical application of the technological process of deep roll hard-to-profi e tapered threads with rollers.
Conclusions
Application of deep roll made it possible to reduce the likelihood of destruction pipes 3 times, to obtain significant economic benefit from increasing their durability and increase the competitiveness of the production of drill pipes in Russia.