A. L. Vorontsov, D. A. Lebedeva (The Bauman Moscow State Technical University, Moscow)
The study of combined extrusion of tumblers with the co-bottom part.
Part 12. Methodology for calculating technological parameters of free extrusion at initial deformation by bending
The method of calculating the energy-force and deformation parameters of the process of free extrusion of nozzles with a conical bottom part, starting from the bend of the workpiece is described. The extrusion of both non-hardening and hardening material 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 the yield stress.
Keywords: forging; tumblers with the co-bottom part; combined extrusion; stresses; deformations.
V. N. Loginov, Z. V. Shirokova (Komsomolsk-on-Amure State University, Komsomolsk-on-Amur)
Calculation of the stress-strain state of a sheet blank during stamping with an elastic medium
The paper considers one of the options for calculating the stress-strain state of a sheet blank during stamping with an elastic medium. On the basis of the method of variable parameters of elasticity, a system of equations for stresses and deformations arising in a sheet blank under load is obtained and solved. In the future, these results are used to calculate the springback of the workpiece after removing the active load.
Keywords: stress-strain state; variable parameters of elasticity; elastic medium; equilibrium equations; intensity of stresses and deformations; single curve.
M. N. Mantusov (PJSC «TUPOLEV», Ulyanovsk branch, Ulyanovsk)
Stamping of curved flanges of sheet parts with elastomer with the imposition of tangential compression
The results of analytical and experimental studies of bending of curved flanges of sheet parts with an elastomer with tangential compression of the flanges material in the bending radius are presented. Stamping of products is carried out in two passes. After the first transition, the part has a significant thinning of the wall in the radius part. The second transition is carried out on a special form block, on which a wave of excess material is formed, providing an increase in the thickness of the part in the bend radius zone.
Keywords: stamping with elastomer; thin sheet parts; wall thinning; constrained bending; allowance.
A. E. Volkov (FGBOU VPO «MSTU» STANKIN», Moscow); S. A. Vorontsov, D. R. Akhkiyamov (PJSC «KAMAZ», Naberezhnye Chelny), E. B. Volkov (LLC RI-Group, Naberezhnye Chelny)
New contour of the straight tooth of the bevel gear
A method for calculating a new contour of a straight tooth of a bevel gear modified for stamping is presented. The contour of the bottom of the cavity of the modified tooth is a broken line, consisting of three segments: an inclined segment at the inner end, a segment of the generatrix of the cone of the cavities, and an inclined segment at the outer end. In the modified contour, the vertex tape near the outer end is cut at an angle to the wheel axis. Four variants of the modified circuit are described. Presented is a satellite for the differential of the rear axle of a car with a modified contour of the teeth, calculated by the described method, made by stamping methods.
Keywords: differential of the rear axle of a car; bevel wheels with straight teeth; stamping; modified tooth contour; contour program.
A. N. Malyshev, S. A. Bysov (Kaluga Branch of the «Moscow State Technical University named after N. E. Bauman», Kaluga ); V. D. Kuhar, V. A. Korotkov (Tula State University, Tula); V. V. Vikhorev (JSC «AvtoKom», Kaluga)
Stretching of sheet blanks of variable thickness for the manufacture of body parts for the electrical industry
This article presents examples of the introduction of blanks of variable thickness for the manufacture of parts for the electrical industry, where the main forming punching operation is "drawing". A review of the use of blanks of variable thickness for the manufacture of products in the aerospace, automotive industry and other areas of the national economy is carried out; examples of the use of cylindrical and box-shaped parts made from blanks of variable thickness are presented.
Keywords: stamping; drawing; initial billet; rolled billet; welded billet; billet of variable thickness; intensification of sheet stamping.
S. M. Vaytsekhovich, L. M. Ovechkin, A. I. Kuzin, A. Yu. Zhuravlev (FSUE «NPO «Technomash» named after S. A. Afanasyev, Moscow)
Developing a device for angular equal-channel compression with twisting
The strategy of the production process of metal bars ejection by equal-channel angular extrusion is developed. Influence of deformation summing up from simple shear (angle extrusion) and pure shear deformation (twisting) on mechanical properties of the end product and on increase of extruding equipment productivity is shown. A testing device for mastering the technology of multistage plastic deformation of metals and alloys is developed. There is also given the analysis of parameters of equal-channel angular extrusion with twisting of metal billets in back pressure conditions and without it.
Keywords: metal treatment under pressure; plastic deformation; shear; metal flow; punch equipment; die; punch; EC-extrusion.