Improvement of Plate’s Shape for Ingots Upsetting

2015 ◽  
Vol 806 ◽  
pp. 141-150
Author(s):  
Oleg E. Markov ◽  
Natalia A. Rudenko ◽  
Igor A. Grachov ◽  
Aleksandar Ristovski ◽  
Vladimir Radojičić
Keyword(s):  
Strain State ◽  
Theoretical Research ◽  
Uniform Stress ◽  
Flat Plates ◽  
Stress Strain ◽  
Stress Strain State ◽  
Axial Defects ◽  
Cylindrical Steel ◽  
Axial Defect ◽  
Main Influence

A stress-strain state and a resize of an axial defect during upsetting have been investigated in the article. Theoretical research based on a FEM has been conducted. The upsetting of cylindrical steel workpieces which had the axial defect equal to 10 % of the workpiece diameter has been simulated. Upsetting has been carried out by flat, concave-conical and convex plates (solid or with hole). The result of the studies showed that the main influence on the workpiece shape had a ratio of dimensions. The maximal closure of the axial defect provides upsetting by concave-conical solid plates. Upsetting by flat plates does not provide the closure of axial defects. Convex plates provide the uniform stress-strain state along the workpiece cross section. The hole in the plates increases the non-uniformity of strain distribution and also does not provide the axial defects closure.

Modeling of Direct Extrusion of Porous Powder Billets

2012 ◽  
Vol 566 ◽  
pp. 267-270
Author(s):  
Lyudmila Ryabicheva ◽  
Dmytro Usatyuk ◽  
Nikolaj Beloshitskij
Keyword(s):  
Strain State ◽  
Plasticity Theory ◽  
Relative Depth ◽  
Porous Powder ◽  
Uniform Stress ◽  
Stress Strain ◽  
Direct Extrusion ◽  
Stress Strain State ◽  
Optimal Value ◽  
Powder Billet

The computer modeling results for direct extrusion of porous powder billets on a basis of the plasticity theory relations are presented. Distributions of stress-strain state parameters and density during direct extrusion of hollow detail from copper powder billet have obtained. The optimal value of backpressure, that ensures a uniform stress-strain state and given density of detail have found. The dependences of backpressure value from relative depth of cavity and extrusion pressure from backpressure are recommended.

scholarly journals Assessment of stress-strain state in cylindrical parts after transverse running with flat plates

2017 ◽  
Vol 2 (5) ◽  
pp. 38-43 ◽  
Author(s):  
Семен Зайдес ◽  
Semen Zaides ◽  
Дак Фам ◽  
Dac Pham
Keyword(s):  
Plastic Deformation ◽  
Strain State ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Flat Plates ◽  
Stress Strain ◽  
Program Complex ◽  
Vertical Loading ◽  
Stress Strain State ◽  
Cylindrical Parts

For the deformation strengthening of parts like axles, pins, and bushes there is offered a method of surface plastic deformation based on blank rolling with flat plates. The method allows machining parts which do not have center holes. At transverse running a blank bending affected by transverse loading forces is excluded. With the aid of ANSYS program complex there is considered a change of a stress-strain state in cylindrical parts at transverse running. There are defined plastic and elastic cylinder deformations after loading. The distribution of residual stresses along cylinder section in the plane of vertical loading is obtained. The stress state of samples run with flat plates on equivalent stress is assessed. An efficient value of running at transverse running used as a basic parameter of surface plastic deformation is defined.

scholarly journals Cylindrical steel tank stress-strain state evaluation with operational loads taken into account

2014 ◽  
pp. 329-344
Author(s):  
S. M. Mansurovа ◽  
R.R. Tlyashevа ◽  
A.V. Ivakin ◽  
G.A. Shayzakov ◽  
A.S. Bayramgulov
Keyword(s):  
Strain State ◽  
Stress Strain ◽  
Stress Strain State ◽  
State Evaluation ◽  
Steel Tank ◽  
Cylindrical Steel

scholarly journals INVESTIGATION OF STRESS-STRAIN STATE OF TRANSVERSELY ISOTROPIC PLATES UNDER BENDING USING EQUATION OF STATICS {1,2} –APPROXIMATION

2016 ◽  
Vol 5 ◽  
pp. 58-66
Author(s):  
Igor Bokov ◽  
Natalia Bondarenko ◽  
Elena Strelnikova
Keyword(s):  
Fundamental Solution ◽  
Strain State ◽  
Integral Transform ◽  
Technical Problem ◽  
Transversely Isotropic ◽  
Flat Plates ◽  
Stress Strain ◽  
Concentrated Force ◽  
Stress Strain State ◽  
Isotropic Plates

The study examined the construction of the fundamental solution for the equations of statics {1,2} – approximation for transversely isotropic plates under bending with the action of concentrated force. Equations {1,2} -approximation were obtained by the decomposition method in the thickness coordinate using the Legendre polynomials. These equations take into account all the components of the stress tensor, including the transverse shear and normal stresses. Since the classical theory of Kirchhoff-Love doesn’t take account of these stresses, the study on the basis of refined theories of stress-strain state of transversely isotropic plates under the action of concentrated force effects is an important scientific and technical problem. The fundamental solution of obtained equations results using a two-dimensional Fourier integral transform and inverse treatment techniques, built with the help of a special G-function. This method allows reducing the system of resolving differential equations for statics of flat plates and shells to a system of algebraic equations. After that, the inverse Fourier transform restores the fundamental solution. The work was carried out numerical studies that demonstrate patterns of behavior of components of the stress-strain state, depending on the elastic constants of transversely isotropic material. The results play a decisive role in the study of boundary value problems in the mechanics of thin-walled elements of constructions, including under the influence of concentrated and local diverse forces.

scholarly journals Influence of thermal state of the end area of multiple continuous-cast billet on cracking of the ends of hot-rolled breakdown at rolling

2019 ◽  
Vol 62 (7) ◽  
pp. 539-547 ◽  
Author(s):  
E. N. Smirnov ◽  
V. A. Sklyar ◽  
A. N. Smirnov ◽  
V. A. Belevitin ◽  
R. E. Pivovarov
Keyword(s):  
Strain State ◽  
Heating Temperature ◽  
Cast Billet ◽  
Time Interval ◽  
Continuous Cast ◽  
Stress Strain ◽  
Continuous Cast Billet ◽  
Stress Strain State ◽  
Axial Defects ◽  
Hot Rolled

The authors have made an analysis of problems arising in the rolling of continuous-cast billets in the modern mini-metallurgical and rerolling plants. It is shown that the use of trio stands in rolling mills of these plants makes it necessary to obtain billets of multiple lengths from bars (most often of 12-meter length) produced in the rolling shop. The subsequent rolling of such multiple billets has revealed increased cracking of the front edge and, as a result, increased metal consumption. Analysis of the causes of these cracks has been made. It was indicated that this defect can appear as a result of a certain stress-strain state formed at the end of hot-rolled breakdown. It is caused by the presence of an uneven temperature field due to more intensive end cooling, to reduction mode in the trio stand and to the presence of axial defects in the continuous-cast billet. The study was conducted on the industrial medium-grade mill 500/370, as well as using mathematical modeling by finite element method. The influence of a set of technological factors, such as temperature of the billets heating before rolling, the time interval of their transportation on the site “heating furnace – first stand of the rolling mill” and parameters of the macrostructure of axial area of the metal were investigated. Calculations by the developed mathematical model have indicated the need to take into account the presence of a scale layer on the heated continuous-cast billet. It is shown that depending on the heating temperature and transport time, the temperature difference at the billet’s end compared to the heating temperature can be from 45 to 100  °C. It will lead to an uneven distribution of deformation resistance and unfavorable stress-strain state at the billet’s end. In addition, the presence of an axial defect can affect the cracking because of its shape and its transformation during reduction. Obtained experimental data allowed hypothesizing the mechanism of transformation of discontinuity defects into cracks at the billet’s end due to the conditions of continuous casting and cutting of billets during rolling in the reduction stand.

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