Tula State University (Tula, Russia):

V. D. Kukhar, Dr. Eng., Prof., Head of Dept. “Theoretical Mechanics”
A. E. Kireeva, Cand. Eng., Associate Prof., Dept. “Theoretical Mechanics”, e-mail: kirealena30@gmail.com

The products of defense technology has a wide range of deep, hollow, thin-walled axisymmetric parts of various profi les. Depending on the type, purpose of the product and the conditions of combat use dimensions, the ratio of height to diameter, wall thickness of the part vary widely. In this paper, the object of study was chosen shell high-explosive ordnance, which is an axisymmetric part with internal spiral corrugations. Production of axisymmetric shells with a given grid of rhombic corrugations is a complex technological task. There are not many practical ways and technologies to cope with this task in the conditions of mass production. The methods that allow you to immediately form a mesh of corrugations of almost any shape on the surface of the part include: electron beam processing; electrochemical processing; laser technology; all kinds of precision casting; cutting technology, which is characterized by low productivity, high tool costs. One of the effective processes for obtaining screw grooves is rotary forging, which eliminates the formation of chips, improves the physical and mechanical characteristics of the material of the product and is more productive than the cutting operation. The disadvantages of the rotary forging process include signifi cant time costs, which are associated with the cyclical loading process and the inability to obtain two directions of corrugation simultaneously. It was previously found that the most effective method of obtaining fonts on the inner surface of a cylindrical workpiece is its reduction profi le punch through a cylindrical matrix. In work an integrated assessment of the force regimes for each of the above operations was carried out. However, it is impossible to assess the stability of the process of reduction without destruction of the material without studying its stress-strain state in the entire volume of the product. In this regard, this article presents the results of theoretical studies of the stress-strain state of the material in the formation of corrugations on the inner surface of the shell at all stages of their production.
The work was conducted within the framework of the grant NSh-2601.2020.8.

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