Kazuki Ikushima^1,*, Shintaro Maeda², Masakazu Shibahara¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.4, pp. 175-175, 2019, DOI:10.32604/icces.2019.05542

Abstract Large-scale thin-plate structures including ships are constructed by welding, and distortion can occur after welding. Welding deformation can increase cost and work time, and so it is important to investigate welding deformation before construction. In this research, to predict welding deformation on the construction of a large thin-plate structure, Idealized Explicit FEM (IEFEM) was applied to the analysis of welding deformation on the construction of a ship hull block. In addition, to efficiently analyze deformation of the whole structure of a large-scale structure, an algebraic multigrid (AMG) method was introduced into the IEFEM. Then, this multigrid IEFEM (MGIEFEM) was applied… More >

L. Donati, L. Tomesani

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.1, pp. 37-38, 2009, DOI:10.3970/icces.2009.012.037

Abstract In recent years aluminum extruded hollow profiles are increasingly used in near-net shape manufacturing processes such as bending and hydroforming; in fact, by applying these secondary processes, it is possible to obtain very high complex parts, especially for the transport industry. It is known that hollow profiles obtained by direct hot extrusion necessarily have some longitudinal welding lines (so called seam welds) produced inside the die and it is common experience, during secondary forming processes, the appearance of early cracking in proximity of those lines [1,2]. At the same time, the direct hot extrusion is the only process able to… More >

Kuen Ming Shu¹, Chien Chih Chen²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.11, No.4, pp. 109-110, 2009, DOI:10.3970/icces.2009.011.109

Abstract Ultrasonic welding is the joining or reforming of thermoplastics through the use of heat generated from high-frequency mechanical motion. Rotary welding is a technique to press two parts together and one part is hold fixed the other rotates at high speed, the friction between the two parts generate heat which causes the parts to melt at the interface, when rotation stops, the weld cools down and solidifies. In this research, an experimental set-up integrated these two different welding processes in one machine set was designed and fabricated to provide a tool to study the integrated welding mechanism.
In this study,… More >

K. Yamamoto¹, M. Tanaka¹, S. Tashiro¹, K. Nakata¹, K. Yamazaki², E. Yamamoto², K. Suzuki², A. B. Murphy³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 1-6, 2008, DOI:10.3970/icces.2008.007.001

Abstract Authors have used a numerical model of stationary helium TIG arc welding taking into account the iron, chromium and manganese vapors produced from the weld pool surface and have simulated the distribution of the metal vapors, plasma temperature, fluid flow velocity and the formation of the weld pool. The concentration of manganese vapor in arc plasma was much higher compared with the composition of manganese for stainless steel. More >

Jin Yeon Cho¹, Jae Mo An², You Me Song¹, Seungsoo Lee¹, Dong Whan Choi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.1, pp. 1-18, 2005, DOI:10.3970/cmes.2005.009.001

Abstract A displacement welding technique is proposed to carry out coupled analysis of the integrated whole model which consists of independently modeled finite element substructures. In the proposed method, the incompatible displacement fields in the interfaces of independently modeled substructures are directly welded together through a blended function that is newly defined in the transient region of mismatching interface. To construct the blended function, the moving least squares function, which does not require well-defined nodal connectivity, is utilized along with the original finite element shape function. The meshless character of the moving least squares function makes it possible to efficiently handle… More >

Hui Huang, Hidekazu Murakawa

CMES-Computer Modeling in Engineering & Sciences, Vol.106, No.3, pp. 187-201, 2015, DOI:10.3970/cmes.2015.106.187

Abstract Dynamic mesh refining method (DMRM) developed previously was extended to multi-level refinement, and employed to perform thermal-mechanical analysis of fillet welding. The DMRM has been successfully incorporated with another efficient technique, the iterative substructure method (ISM) to greatly enhance the computation speed of welding simulation. The basic concept, hierarchical modeling and computation flowchart are described for the proposed method. A flange-to-pipe welding problem has been solved with a commercial code and the novel method to demonstrate its high accuracy and efficiency. Furthermore, the numerical analysis was performed on a large scale stiffened welding structure, and comparison of welding deformation between… More >

L. Novotný¹, M. Tsunori²

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.3&4, pp. 253-264, 2011, DOI:10.32604/cmes.2011.082.253

Abstract The welding simulation is carried out by an uncoupled thermal and mechanical analysis or by a coupled thermo-mechanical analysis. For weld-induced distortion and residual stress simulation, nonlinear mechanical analysis is required. Nonlinearities are caused by both nonlinear behaviour of the material and geometrical nonlinearity. Usually, the element birth technique is used to incorporate the filler material in the model. The ideal straight geometry may be altered by imperfections to enable buckling behaviour. Real component shapes contain various imperfections (e.g. geometrical, material). The finite element mesh may contain geometrical imperfections too. When a simple weld model is used, the mode of… More >

Rui Wang¹, Jianxun Zhang¹, Hisashi Serizawa², Hidekazu Murakawa²

CMES-Computer Modeling in Engineering & Sciences, Vol.44, No.1, pp. 97-114, 2009, DOI:10.3970/cmes.2009.044.097

Abstract In this paper, the inherent deformation of fillet welded thin plate T-joints is studied. The prediction procedure of inherent deformation consists of three parts: part one, a three dimensional (3D) thermo-elastic-plastic analysis using an in house finite element (FE) code of interactive substructure method (ISM) is utilized to obtain the welding distortions; part two, corresponding experiments are carried out to verify the computational results of ISM; part three, using the verified computational results, the inverse analysis is utilized to evaluate the welding inherent deformation. Based on the results in this study, an inherent deformations database of fillet welded thin plate… More >

Tae-Jong Yun¹, Won-Bin Oh¹, Bo-Ram Lee¹, Joon-Sik Son², Ill-soo Kim^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.1, pp. 1-14, 2019, DOI:10.32604/fdmp.2019.04759

Abstract Detection of weld defects using real-time monitoring and controlling algorithm is of the significant task in manufacturing industries due to the increased production and liability costs that result when weld defects are not identified early in the production cycle. Monitoring and controlling for robotic arc welding process employed should be reliable, flexible and cost-effective in non-clean, high-volume production environments. Also, the robotic welding system has been utilized a complex jigging and mechanical devices to move the workpiece which related to the stationary welding head for getting higher efficiency and lower costs. To develop the fully robotic welding system, people make… More >

Adeline Tchikango Siagam¹, Gunther Brenner¹, Peter Giese², Volker Wesling²

FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.2, pp. 77-84, 2008, DOI:10.3970/fdmp.2008.004.077

Abstract The PTA (''Plasma-Transferred-Arc'') is a widespread variant of plasma powder processes to manufacture coatings against corrosion or abrasion. For the optimization of this technique, an explanation of the processes which lead to a maximal deposition performance (i.e. maximal quantity of powder converted per time) is required. Especially the gas and particle flow in the region between the burner nozzle and the work piece is of interest. In the present study, flow simulations (Computational Fluid Dynamics, CFD) have been done in order to investigate the determining factors for the dimensioning of the processes. Additionally, velocity measurements have been obtained with PIV… More >