National University of Science and Technology “MISiS” (Moscow, Russia):

M. V. Kadach, Post-graduate, e-mail: stendek89@yandex.ru
A. N. Koshmin, Post-graduate, e-mail: madswom@yandex.ru
Yu. V. Gamin, Cand. Eng., Senior lecturer, e-mail: gamin910@gmail.com
B. A. Romantsev, Dr. Eng., Prof., e-mail: boralr@yandex.ru

A process for production of steel tubular items of a variable cross-section along the length, based on the technology of longitudinal rolling in rolls with grooves of a variable profile, forming an eccentric pass, has been proposed. The items have a smoothly varying cross-sectional shape along the length from a flat-oval one at the ends to the cylindrical at the central section. The main axes of the ovals at the end sections are mutually perpendicular. These items can be used as components of a cooling jacket for heat-loaded flow paths of power plants. The possibility of using the proposed process to create the industrial technology for manufacturing tubes of a similar assortment used in the aerospace industry has been confirmed by experiments. According to the results of trial rolling, product samples were obtained, the geometrical dimensions of which meet the requirements for defect-free assembly of the cooling jacket.

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