Vdovin S.I., Lunin K.S., Mikhailov V.N., Fedorov T.V.

Engineering theory of flexible pipes and bending moment

The study describes the theoretical aspects of pipe bending process. The article discusses the possible methods of determining the size of pipe sections that have undergone a change in the bending process. It is used a system of assumptions that are acceptable from an engineering point of view. It is proposed selective equilibrium conditions for the calculation of the curved pipe reducing the height of the cross sections, the solution is given in comparison with the known formulas obtained by the variational method. Among the equilibrium conditions of the new method of calculation are the parameters of the functions approximating the radial and circumferential displacement. It is also revealed that in comparison with variational (energy) approach eliminates the need to use some serious assumptions, accordingly, increases the accuracy of the results. The proposed equilibrium conditions associated with the selection of unknown values in the interactive use of the program MatCAD.
Keywords: pipe bending; variational method; functions of displacements; selection values of the unknowns; MathCAD.

Shemonaeva E. S.

Peculiarities of the forming process of parts with the shape of a half from sheet blanks

Tre article presents the theoretical and experimental studies of the process of molding parts with the shape of a half. Theoretical studies of this process provide an opportunity to determine the technological capabilities of the forming and the parameters of the parts. The influence estimation of sheet thickness variation of the workpiece and the magnitude of the tightening flange in the forming area for the geometric parameters obtained details is given. The experiments forming process of polution are conducted in two ways: from the blank in cold conditions and with pre-heat. It is presented a comparison of the obtained theoretical and experimental data.
Keywords: sheet-metal stamping; forming; variations in thickness.

Danilin G.A., Ageev N.P., Filin D.S., Titov V.A., Zaterucha E.V. Lobov V.A., Ivanov V.N.

Study of the possibilities of the combined longitudinal-lateral extrusion of steel billets

The article describes the process of longitudinal-lateral extrusion of steel billets. The results of the analysis of stress-strain state of the workpieces are established that the limitation of the process depends on transverse strength of the lateral surface of the workpiece and the force loads on the tool. It is proposed deformation criterion to estimate the strength of the workpieces, the adequacy of which is proved by experimental studies. The results allow to determine the optimal size of the working tool for the fabrication of parts using longitudinal-lateral extrusion. Experimental verification of the possibilities of the process performed on copper samples shows a slight deviation technology forces from computer simulation at each stage of the process. The ability to manufacture semi-finished products with high surface quality curved portion, which contributes to its reliable centering on further operations is proved. In addition, recommendations on the implementation of the process in production are shown.
Keywords: cold forging; composite extrusion; the factor of the use of material; technological power; the allowable deformation; unit load; longitudinal-lateral extrusion.

Zhbankov I.G.

Ways of the improvement of open die forging discs

Analysis of the schemes open die forging discs is made. Based on this analysis it is shown systematization of a factors influenced on stress-strain state of billet. Determined basic ways of the further perfection the processes forging discs. Proposed for design the new schemes of forging discs use the method of morphology cards. This method must be used with the aid of basic structural elements which have the most influence on stress-strain state of billet. Determined that the method of morphology cards allows to generate over 10000 schemes of forging discs. For example proposed three scheme of forging of billets with inhomogeneous temperature field that must allow increase accuracy of obtained forgings and expand the nomenclature of obtained parts by forging with flat plates. By the finite element method is made simulation of proposed schemes.
Keywords: forging; disc; upsetting; plates; finite element method; simulation; method of morphology cards.

Artes A.E., Tret’yuhin V.V.

New technologies of aluminum alloys using in the manufacture of parts of mechanisms and machines

The article provides an overview of the status of production and consumption of aluminum alloy sections in Russia and abroad. It is presented the development of the Department "Systems of plastic deformation", which is working on the creation of new and improvement of known technologies for the efficient processing of aluminium instead of steel and cast iron in the manufacture of parts engineering application. The new technology of extruding various impellers and other products with fine ribs is shown. It is also described an alternative of forging with small holes bases for use as an internal needle high strength aluminum wire, which manages before fusing to form an opening equal to the diameter of the wire. In addition, the technology which applies to the surface of the forgings the corrosion superhard coatings after machining by the method of microarc oxidation is noted.
Keywords: aluminium; extrusion; forging; thin ribs; method of microarc oxidation.

Kornilov A.V.

Destruction peculiarities of tool steel X12MФ

The article is devoted to the analysis of the tool steel Х12МФ. A review of works devoted to this mark is shown. It is carried out impact tests and tests on static crack resistance that demonstrate the extreme fragility of steel Х12МФ. During the tests is confirmed the predictions of the specificity testing of materials such as hardened steels. It is found a lack of conventional yield strength and endurance limit in the samples. Studies of magnetic properties also show that this steel in the condition ser by GOST (State standard) is fractured by brittle scheme. It is recommended to introduce the coercive force into the list of characteristics of tool materials to be regulated by State standards as it correlates clearly unequivocally to fracturing characteristics, but its determination does not need significant financial, time expenditures and high professional skills of an operator.
Keywords: strength limit; fracture viscosity; kinetic diagram of fatigue fracture; coercive force.

Fazlyahmetov R.F., Medvedev E.B., Polozovsky V.A.

Influence of tool heating and the gap size on the die cavity filling during the forging of crystallizing Babbitt B83

Investigations on the influence of the mode of liquid stumping of babbitt B83 on the occupancy of the die cavity at different temperatures and the size of the gap between the parts of the stamp were carried out. The features of the structure of babbit B83 when squeezing into the gaps of the stamp under different temperature conditions of crystallization were investigates. On the example of babbitt B83 shown that adjusting the gaps in the die and the heating temperature of the matrix with the liquid forging affects the nature of the flow of crystallizing metal.
Keywords: liquid forging; babbitt; stamp; clearances; crystallization; structure.

Loginov Yu.N., Babailov N.A., Pervuhina D.N.

Modeling in the software package ABAQUS of process of compaction of the porous material

Using the software system ABAQUS, modeling of the copper powder compaction process was performed with the relative initial porosity of 10 % in three variants of input friction conditions: without friction and friction coefficient was 0.2 and 0.4. The Garzon’s yield condition for plastically compressible continuum was applied. Regularities of the vector components displacement distribution, density, hydrostatic stress during porous material compacting in the container were identified. If the friction coefficient is 0.4, it will be revealed two strains hindered zones - under punch and on the punch periphery at the greatest distance from the active punch. Angles reversal principal strains were defined. Area of the largest rotation was revealed in the main deformation periphery region of the workpiece adjacent to the die surface. In this area, the minimum principal strain (compression) deploy at almost 45 degrees to the corresponding rotation of the maximum principal strains. The comparison of the known experimental data performed, and it show good qualitative convergence results.
Keywords: powder compaction process; briquette; plastic deformation; volumetric deformation; density; software system ABAQUS.