**A. L. Vorontsov, D. A. Lebedeva (The Bauman Moscow State Technical University, Moscow)**

**The study of combined extrusion of tumblers with a co-bottom part.**

**Part 16. Methodology for calculating technological parameters of free extrusion at initial deformation by shear of the central area**

*The method of calculating the energy-force and deformation parameters of the process of free extrusion of nozzles with a co-bottom part, starting with a shift in the central area of the workpiece, is described. Extrusion of both non-hardening and hardening materials is considered. In the latter case, the account of the hardening of the extruded material is described in detail. The above formulas make it possible to determine such important parameters of the stamping process as total and specific deforming force, maximum pressure on the die wall, and increase in yield stress.***Keywords:** forging; tumblers with the co-bottom part; combined extrusion; stresses; deformations.

**A. E. Tsibulko, E. A. Romanenko (PJSC «NKZM», Kramatorsk, Ukraine)**

**The choice of criteria for the strength of materials according to the maximum coefficient of adaptability to the type of stress state**

*Expressions are proposed for calculating the coefficients of adaptability of criteria for the strength of materials to the type of stress state, which provide a quantitative assessment of the possibility of their application for a deformed material under hard and soft loadings.* **Keywords:** strength; crack; shift; normal, tangential, total, equivalent stresses; ball tensor.

**F. F. Khabibullin, T. A. Mustafayev, A. V. Tazhibaeva, V. N. Krymova (Kazan National Research Technical University named after A. N. Tupolev – KAI, Kazan)**

**Kinematics of the spatial 6R mechanism**

*This article presents a kinematic scheme of the spatial 6R mechanism, which describes in detail the mechanism of performing rotational movements around its own geometric axes. Based on the obtained mechanism, calculations of the projections of radius vectors, projections on the XYZ coordinate axis, the radius vector module, the projection of the velocity vector of the characteristic point, the projection of the acceleration vector of the characteristic point on the XYZ coordinate axis, the linear acceleration module and the linear velocity of the characteristic point are performed. Graphs of the position of a characteristic point depending on the angle of rotation of the leading link were constructed, in addition, graphs of the velocity vector of characteristic points were designed, as well as graphs of projections of the radius vector of characteristic points. Particular attention is paid to the linear velocity and linear acceleration of characteristic points, which are necessary for plotting graphs.***Keywords.** spatial mechanism; nR mechanism; drive; crank.

**Mohamed Sherif El Sayed Ahmed Soliman (Novosibirsk State Technical University, Novosibirsk)**

**Formation of convex rift elements during pipe expansion by the pressure of a pulsed magnetic field**

*The article is devoted to the study of the process of electromagnetic formation, which has gradually become one of the effective methods for overcoming the existing problems in the processing of aircraft alloys. The stresses and strains that can arise during the electromagnetic formation of convex rift elements on a pipe have been determined. The identified formulation is the most suitable of those available for modeling deformation processes, which are characterized by constantly changing geometry and large displacements of individual elements.***Keywords:** convex rift elements; skin effect; skin depth; deformable solid; circumferential deformation.

**A. D. Khwan (Voronezh State University, Voronezh); D. V. Khwan, A. A. Voropaev, Yu. B. Rukin, N. S. Pereslavtseva (Voronezh State Technical University, Voronezh)**

**Soft-mud machine for upsetting with torsion of low cylindrical billets**

*The article discusses the modernized design of the soft-mud machine for upsetting with torsion of cylindrical billets, which allows sufficiently reliably varying over a wide range the relationship between angular and linear deformations in the billet. Application of the proposed design of the press in industry will allow the development of innovative technologies in order to improve the operational properties of structural elements.***Keywords:** press; upsetting with torsion; linear and angular deformations; flywheel; braking device; force.

**M. E. Goydo, V. V. Bodrov, R. M. Bagautdinov (LLC «Ural Engineering Center», Chelyabinsk)**

**Methods of filling the working hydraulic cylinders of hydraulic presses when performing the approach stroke**

*The article discusses the methods of filling the working hydraulic cylinders of hydraulic presses. In the course of the study, technical solutions are given due to which a high-quality (without disrupting the continuity of the liquid) filling of the working cavities of the working hydraulic cylinders during the approaching stroke is provided, and the possibility of refusing to use the filling tank in the hydraulic system is substantiated.***Keywords:** press; hydraulic cylinder; approach progress; liquid; filling tank.

**N. V. Kurlaev, N. A. Ryngach, F. M. Tagoev (Novosibirsk State Technical University, Novosibirsk) **

**Numerical study of the formation of tubular parts of aircraft by the pressure of a pulsed magnetic field**

*The paper considers the numerical simulation of stamping tubular parts by pressure of a pulsed magnetic field by the distribution method. Research has been carried out on the effective plastic deformation and the rate of expansion of a tubular part of an aircraft by the pulsed magnetic field pressure. Results obtained by 3D-finite element modeling using ANSYS software. The calculation results were summarized in the form of a nomogram to determine the required technological modes, taking into account the material properties and the pressure amplitude of the pulsed magnetic field.* **Keywords:** magnetic pulse stamping; tubular part; modeling; finite element method; deformation; nomogram; pressure; ANSYS.

**E. V. Rybak (JSC «Rossiya-Airlines», Saint-Petersburg) **

**Features of maintenance of AIRBUS A320 family aircraft when damaged by foreign objects**

*The article deals with the process of aircraft engine maintenance in case of damage by foreign objects. The entire process is described in three stages, including an example description. The article also describes technologies for preventing birds from entering the aircraft. The goal is to analyze statistics and consequences of damage to aircraft by foreign objects.***Keywords:** maintenance; engineering personnel; statistics; analysis; aircraft; bird; airline.