KSHP. OMD №8-2018

A. L. Vorontsov, E. O. Reshchikov (The Bauman Moscow State Technical University, Moscow)

Investigation of internal radial extrusion of a pipe blank.
Part 1. Actuality and statement of the problem

The urgency of carrying out of research with the purpose of definition of the basic technological parameters of process of internal radial squeezing out of a tubular preparation necessary for successful designing of this operation is proved. The solved mechanic-mathematical problem is formulated and a complete system of necessary initial equations is presented. Formulas are obtained that connect the current geometric parameters of the extruded workpiece with the value of the working stroke of the punch.
Keywords: volumetric stamping; radial extrusion; stresses; deformations; pipe blank.

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

A unified energy theory of strength and fracture of ductile materials in a brittle and viscous state under complex loading

A unified energy theory of the strength of plastic materials in a brittle and viscous states under complex loading is proposed, based on the dependence of the destructive factors: octahedral normal and tangential stresses on the level of the specific potential energy of deformation.
Keywords: strength; voltage; octahedral tangential stress; specific potential energy; deformation.

A. M. Schneiberg, S. V. Ivanov, M. A. Shirshkovа (Nizhny Novgorod State Technical University, Nizhny Novgorod)

Experimental study of the process of combined volumetric stamping in open dies

Experimental power parameters of the combined volumetric stamping process with axial rotation of the tool on the model material (lead) are determined experimentally. The obtained data are compared with the calculated values. The influence of torsion on the degree of filling of the stream is estimated.
Keywords: open stamping; axial force; combined deformation; «compression+torsion».

Yu. D. Gorbunova, A. I. Goriaev («Uralkhimmash» JSC, Ekaterinburg); G. A. Orlov (The Ural Federal University named after the first President of Russia B. N. Yeltsin, Ekateriburg)

The experience of multilayer punching thin-walled bottoms

This article presents the results of the development of the technology of stamping thin-walled bottoms on the «Uralkhimmash» JSC using a multilayer billet. This technology made it possible to produce thin-walled elliptical bottoms of high accuracy with a high quality of the surface, in compliance with the requirements for the temperature treatment regime.
Keywords: hot sheet stamping; elliptical bottoms; thinning.

P. A. Vasilevsky (Kamkor LLC, Kamensk-Uralsky), L. M. Zheleznyak, A. A. Mikhailov (The Ural Federal University named after the first President of Russia B. N. Yeltsin, Ekateriburg)

Features of development and operation of a rolling mill in the manufacture of electrical products

With the use of a modern aggregate - rolling mill on the basis of the designed modes of pre-conditioning and subsequent multiple dragging with sliding, the industrial production of electrical products was mastered. The rectangular sections are intended for the manufacture of copper busbars. From the wedge-shaped stripes, cold stamping produces lamellas for the collectors of electrical machines. Contact wires are designed for urban electric networks.
Keywords: rolling-drawing mill; electrotechnical profiles; wide assortment; technological regimes; industrial production of products.

Yu. N. Loginov, E. G. Polishchuk (The Ural Federal University named after the first President of Russia B. N. Yeltsin, Ekateriburg); A. E. Pervukhin (Ekaterinburg Non-Ferrous Metal Processing Plant JSC, Ekateriburg)

Form changing of surface ring defects with the wire drawing

The question of the behavior of surface annular defects in wire drawing is discussed. For this purpose, the boundary-value problem of deformation by wire drawing in the presence of such defects is posed. The finite element method is used to determine the stress-strain state using the RAPID 2D software module. A decrease in the degree of shear deformation in the defect location zone and an increase in the level of tensile stresses are revealed. It is established that the defect as a result of the passage of drawing is not completely eliminated. It is proposed to apply techniques for improving the state of the surface.
Keywords: drawing; defectiveness; finite element method; stresses; deformations.

G. L. Kolmogorov, T. E. Melnikova (Perm National Research Polytechnic University (PNRPU), Perm)

Plastohydrodynamic effect of lubricant during upsetting

The peculiarities of the process of flow of viscoplastic lubricant during compression between surfaces of absolutely rigid tools and workpiece during in upset process are investigated. calculations of the thickness of a layer of viscoplastic lubricant during deformation are presented, taking into account rheological characteristics of the lubricant and technological parameters of the sedimentation process. the results of an experimental study of the sedimentation process, taking into account the plastohydrodynamic effect of lubricant using the moire band method, confirmed the effectiveness of the proposed calculation formulas. the obtained ratios, which allow choosing a viscoplastic lubricant from the condition of maintaining the lubricating layer of the required thickness by the end of the billet deposition process, can be used in technological calculations to select the rational parameters of the sedimentation process.
Keywords: upset forging; lubricant; hydrodynamic effect; frictional conditions; deformation; forming processes; moire stripe method.