Three-Dimensional Nonlinear Finite Element Analysis of Hot Radial Forging Process for Large Diameter Tubes

A new method of plate forging with V-shaped dies is proposed. The deformation state of a metal workpiece during forging has been investigated. The proposed method of forging increases the uniformity of the strain distribution with a high level of strain in the workpiece. The values of angles for V-shaped dies range from 120°to 140°. This range of die angles is the most rational from the standpoint of strain distribution uniformity and maximum widening. V-shaped die usage for plate forging leads to an increase in widening coefficient of 35 % in comparison with forging with flat dies. This forging technique provides the possibility of eliminating the operation of billet upsetting during plate forging. V-shaped die usage for plate forging also results in a decrease in deformation load in comparison with flat die forging. The scheme of plate forging by V-shaped dies results in the formation of an irregular compression state in the axial zone. It leads to the closing of defects during forging. The new technology of plate forging with V-shaped dies was tested under industrial conditions. The forged piece has satisfied the requirements of the customer's technical criteria. The ultrasonic check results have shown that the application of the proposed technology provides an increase in metal continuity within the central zone of the forged piece. The experimentally derived forging results have confirmed that upsetting operations can be eliminated, and as a result, energy expenditures and the overall cycle time of the forging operation have been reduced by 15 %.

Section: Literature Review the State Of The Artmentioning

confidence: 99%

“…This governing coupling equation is necessary for determination of the stiffness matrix [K] (1) of the finite element and for determination of stress components {σ} (2) [19,21] using of the elasticity matrix [D], which takes into account the properties of the deformed metal…”

Section: Governing Coupling Equation For An Interconnection Between Fmentioning

confidence: 99%

Development of a new process for forging plates using intensive plastic deformation

Марков

Perig

Markova

et al. 2015

“…Through the introduction of a finite element method [32][33][34][35][36][37][38][39][40] in Deform 3D, a simulation of open die forging with slanted flat dies was accomplished. A three-dimensional model simulation has been performed.…”

Section: Simulation Of Stress-strain Parametersmentioning

confidence: 99%

New schemes of forging plates, shafts, and discs

Zhbankov

Perig

Aliievа

2015

This paper presents the various ways of forging large forged pieces such as shafts, plates, and discs. A finite element method was used to simulate open die forging processes such as forging by flat dies with a slant, forging by staged dies, and upsetting of profiled workpiece. The parameters of the stress strain state of the billet in these processes were determined, along with the rational parameters for forging plates by flat dies with slant such as tool size and mechanical modes. The optimal die step dimension and mechanical regime for forging shafts by staged tools was determined. Also, the rational geometric parameters of the workpiece for forging discs by upsetting were determined. For these forging schemes, a simulation was done of the microstructure evolution in forgings obtained by traditional technology and new proposed technology. The paper shows the advantages of new forging schemes which provide a uniform distribution of grain size in the obtained billets.

“…The results show that the strain of the thin-walled copper tube processed through three-split die radial forging is more uniformly distributed than that obtained through two-split die radial forging under the same work conditions. Chen et al [13,14] developed a quarter-symmetry 3D model to study the effect of die geometry on the void closure during the hot radial forging and analyze the process for large-diameter tubes. They concluded that the predicted reductions for central longitudinal voids are in good agreement with the experimental findings obtained from hot upsetting and hot rolling processes.…”

Section: Introductionmentioning

confidence: 99%

A new net-shape plating technology for axisymmetric metallic parts using rotary swaging

Şchiopu

Luca

2015

This paper summarizes the research work aimed to elaborate a new plating method for axisymmetric metallic parts by precision cold forming on rotary swaging principle and, on this basis, to develop an environmentally friendly technology for net-shape plating. The new technology is intended to create parts with the basic structure made from cheap materials with high fatigue strength, on which, in areas where they require different characteristics (low friction coefficients, greater hardness, greater corrosion resistance, etc.), a layer of more expensive materials that provide these features is applied. At first, the new method of plating through rotary swaging was developed and the net-shape plating technology was preliminarily designed. Then, the experimental technology was analyzed and optimized employing process simulation by finite element method (FEM). A nonlinear finite element analysis (FEA) package, MSC.Marc/Mentat, was used. The full 3D FEM model established in this study eliminates some of the limitations encountered in the previous works using the real movement curve for dies and accurate boundary conditions. The model running tests indicate that the relative positioning between base workpiece and coating tube is of crucial importance in this application. Finally, practical experiments were carried out, the results been used for validation of the 3D simulation model, for physical-mechanical characterization of the joining between base part and coating layer and for technology design finalization. A good agreement between experiments and simulation was found. Also, the experiments indicate that the joint is more tightened when the inside workpiece has a yield strength greater than the outer workpiece.