TMK Research & Development Center, Chelyabinsk, Russia
B. V. Barichko, Cand. Eng., Leading Researcher, Drawing and Pressing Laboratory
K. Yu. Yakovleva, Cand. Eng., Head of Drawing and Pressing Laboratory, e-mail: yakovleva@rosniti.ru

The article presents the results of finite element modeling of the process of profiling seamless thin-walled hexagonal tubes of high precision made of corrosion-resistant steels by deformation on a plug. It provides a brief history of the development of hexagonal tubular products, current requirements for the geometry of hexagonal tubes, identifies existing methods and equipment used for the production of such tubes, as well as the features of their application in the modern nuclear industry. The conditions for setting the modeling problem are given, the features of the stress-strain state of the metal are considered when implementing the profiling process on a plug in two ways: drawing and pushing. Based on the results of the study of the stress-strain state during profiling, the force parameters of the process and the dimensional accuracy of finished pipes are predicted. The prospects for using the developed technical solutions for the profiling process of seamless large-sized hexagonal pipes are shown.

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