Numerical study on forming complex fitting body on end of integrated stainless steel pipe without welds

Abstract

It is necessary to use the integrated stainless steel pipe having two fitting bodies without welds while train travelling at high speed. In order to form this type of integrated stainless steel pipe, the method of preforming combined finish forming process is developed. The preforming process is characterized by flaring combined upsetting for left fitting body which is like a flange, and is characterized by tube axial compressive process under die constraint for right fitting body which is like a double-wall pipe. The finite element simulations of the processes are carried out by software package DEFORM, and the results indicate that: 1) left or right fitting body can be formed by a two-step forming process without folding and under-filling defects; 2) by using two-step forming, strain and stress in left fitting body are larger than those in right fitting body, and deformation in right fitting body is more homogenous than the deformation in left fitting body; 3) two or more preforming steps may be needed for left fitting body considering the distributions of strain and stress.

Keywords

plastic forming / hot forming / flange joint / integrated steel pipe / finite element analysis

References

[1] SawaT, OgataN, NishidaT. Stress analysis and determination of bolt preload in pipe flange connections with gaskets under internal pressure [J]. J Pressure Vessel Technol, 2002, 124(4): 385-396

[2] AbidM, HussainS. Bolt preload scatter and relaxation behaviour during tightening a 4 in-900# flange joint with spiral wound gasket [J]. Proc Inst Mech Eng E: J Process Mech Eng, 2008, 222(2): 123-134

[3] FukuokaT, TakakiT. Finite element simulation of bolt-up process of pipe flange connections with spiral wound gasket [J]. J Pressure Vessel Technol, 2003, 125(4): 371-378

[4] AbidM, HussainS. Relaxation behaviour of gasketed joints during assembly using finite element analysis [J]. Sadhana, 2010, 35(1): 31-43

[5] AbidM, KhanK A, ChatthaJ A. Performance testing of gasketed bolted flange pipe joint under combined pressure and thermal loading [J]. Exp Tech, 2011, 35(6): 35-37

[6] AbidM, SiddiqueM. Numerical Simulation to study the effect of tack welds and root gap on welding deformation and residual stresses of a pipe-flange joint [J]. Int J Pressure Vessels Piping, 2005, 82(11): 860-871

[7] HuX L, WangZ R. Numerical simulation and experimental study on the multi-step upsetting of thick and wide flange on the end of a pipe [J]. J Mater Process Technol, 2004, 151(1/2/3): 321-327

[8] SunZ C, YangH. Free deformation mechanism and change of forming mode in tube inversion under conical die [J]. J Mater Process Technol, 2006, 177(1/2/3): 171-174

[9] SunZ C, YangH. Study on forming limit and feasibility of tube axial compressive process [J]. J Mater Process Technol, 2007, 187/188: 292-295

[10] FengW, HuaL, HanX H. Finite element analysis and simulation for cold precision forging of a helical gear [J]. Journal of Central South University, 2012, 19(12): 3369-3377

[11] LiJ C, WangB, ZhouT G. Analysis and optimization of variable depth increments in sheet metal incremental forming [J]. Journal of Central South University, 2014, 21(7): 2553-2559

[12] NguyenD T, DinhD K, NguyenH, MT, BanhT L, KimY S. Formability improvement and blank shape definition for deep drawing of cylindrical cup with complex curve profile from SPCC sheets using FEM [J]. Journal of Central South University, 2014, 21(1): 27-34

[13] Rare Metal Mater Eng, 2016, 45(1

[14] SemiatinS L, GoetzR T, ShellE B, SeetharamanV, GhoshA K. Cavitation and failure during hot forging of Ti-6Al-4V [J]. Metall Mater Trans A, 1999, 30A: 1411-1424

[15] ZhangD W, YangH, SunZ C. 3D-FE modelling and simulation of multi-way loading process for multi-ported valve [J]. Steel Res Int, 2010, 813): 210-215

[16] LemaitreJA course on damage mechanics [M], 1992BerlinSpringer-Verlag

[17] KobayashiS, OhS I, AltanTMetal forming and the finite-element method [M], 1989New YorkOxford University Press

[18] TanX. Comparisons of friction models in bulk metal forming [J]. Tribol Int, 2002, 35: 385-393

[19] SFT Inc.DEFORMTM Integrated 2D-3D Version 10.2 and DEFORMTM v11.0 (Beta) User’s Manual [M], 2011Columbus, OhioScientific Forming Technologies Corporation

[20] GanY, TianZ-l, DengH, FengD, WangX-linChina materials engineering canon: Volume 3 [M], 2005BeijingChemical Industry Press