Tula State University (Tula, Russia):

V. D. Kukhar, Dr. Eng., Prof., Head of the Dept. of Theoretical Mechanics, e-mail: Fiz-site@yandex.ru
V. A. Korotkov, Cand. Eng., Associate Prof.
S. S. Yakovlev, Post-graduate Student
A. A. Shishkina, Student

Manufacture of shells with a mesh of rhombic ribbings is a complex technological task, for the solution of which it is possible to use cutting operations, electrochemical methods, laser technologies, however, all of the above methods are ineffective. Methods of processing metals by forming are also used, among which the most common is reduction. An alternative method is the local deformation of a cylindrical workpiece with a tool with a working mandrel, on which there are spiral wedge protrusions. For this, a device is used in which the working mandrel with protrusions has the ability to move along the formed cylindrical shell and make a rotational movement around an axis. Rifling with multi-start spiral riffles can be carried out using a working mandrel with a different shape of the lead-in geometry of spiral wedge protrusions and their height on its working surface, therefore, the substantiation of the shape and size of the spiral wedge protrusions is an important and urgent task.
The work was carried out within the framework of the grant of the Government of the Tula region in the field of science and technology No. DS / 167.

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