Effect of welding sequences on the welding stress and distortion in the CFETR vacuum vessel assembly using finite element simulation

Zhang, Jingwen; Yu, Liming; Liu, Yongchang; Li, Huijun; Liu, Chenxi; Wu, Ji; Ma, Jin; Li, Zhanlun

doi:10.1016/j.ijpvp.2019.103930

Cited by 15 publications

(5 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…After applying control measures for analysis, the optimal welding sequence is consistent with the above, and the welding deformation is greatly reduced compared to the previous deformation as shown in table 9. The analysis results and welding deformation control measures of the port stubs and 1/8 VV are similar to the PSs [23,24].…”

Section: Welding Deformation Analysissupporting

confidence: 56%

R&D achievements for vacuum vessel towards CFETR construction

Liu

et al. 2020

Nucl. Fusion

Self Cite

View full text Add to dashboard Cite

The next generation of magnetic confinement fusion experimental facility, the China Fusion Engineering Test Reactor (CFETR), is currently undergoing physical and engineering design. The essential technology research and development projects related to CFETR manufacture are in progress. As one of the demo projects for CFETR R&D, a 1/8 full-scaled vacuum vessel (VV), which aims to solve the key technologies of forming, welding, measurement, assembly, etc in the future manufacturing process of VV, was initiated in 2015 by Institute of Plasma Physics Chinese Academy of Science (ASIPP). The fabrication of two full-scaled 22.5° toroidal sectors, which are composed of two 11.25° sectors, was successfully completed in June 2019. In the manufacturing process of the VV mockup, the progress has been made in the following six aspects: engineering design and safety evaluation of the VV mockup, the high-precision forming of the hyperbolic shell, the welding deformation control of 50 mm thick full penetration structure, the nondestructive testing of the complex welds by full volume covering, the establishment of high-precision 3D measurement fiducial network and the high-precision assembly of the VV parts. This article describes the progress and achievements of the above six aspects for the CFETR VV.

show abstract

Section: Welding Deformation Analysissupporting

confidence: 56%

R&D achievements for vacuum vessel towards CFETR construction

Liu

et al. 2020

Nucl. Fusion

Self Cite

View full text Add to dashboard Cite

show abstract

“…The calibration method of this study was examined by analysing the comparison of transient temperature distribution between WAAM simulation and experiment. This calibration method has been utilized by numerous researchers in similar areas in order to ensure the optimization of thermal parameters in their simulation [30][31][32]. The usage of thermal distribution on WAAM processes was also executed by comparing experimental and simulation of WAAM [33].…”

Section: Vm Procedures For Thermal Calibrationmentioning

confidence: 99%

Methodical procedure of virtual manufacturing for analysing WAAM distortion along with experimental verification

Prajadhiana¹,

Manurung²,

Bauer³

et al. 2021

JAEDS

View full text Add to dashboard Cite

This paper deals with a principal development of virtual manufacturing (VM) procedure to predict substrate distortion induced by Wire Arc Additive Manufacturing (WAAM) process. In this procedure, a hollow shape is designed in a thin-walled form made of stainless steel. The procedure starts with geometrical modelling of WAAM component consisting of twenty-five deposited layers with austenitic stainless-steel wire SS316L as feedstock and SS304 as substrate material. The hollow shape is modelled based on simplified rectangular mesh geometry with identical specimen dimensions during the experiment. Material model to be defined can be retrieved directly from a database or by conducting a basic experiment to obtain the evolution of material composition, characterized using Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray (EDX) analysis, and generated using advanced modelling software JMATPRO for creating new properties including the flow curves. Further, a coupled thermomechanical solution is adopted, including phase-change phenomena defined in latent heat, whereby temperature history due to successive layer deposition is simulated by coupling the heat transfer and mechanical analysis. Transient thermal distribution is calibrated from an experiment obtained from thermocouple analysis at two reference measurement locations. New heat transfer coefficients are to be adjusted to reflect actual temperature change. As the following procedure prior to simulation execution, a sensitivity analysis was conducted to find the optimal number of elements or mesh size towards temperature distribution. The last procedure executes the thermomechanical numerical simulation and analysis the post-processing results. Based on all aspects in VM procedures and boundary conditions, WAAM distortion is verified using a robotic welding system equipped with a pulsed power source. The experimental substrate distortion is measured at various points before and after the process. It can be concluded based on the adjusted model and experimental verification that using nonlinear numerical computation, the prediction of substrate distortion with evolved material property of component yields far better result which has the relative error less than 11% in a comparison to database material which has 22%, almost doubled the inaccuracy.

show abstract

“…Zhang et al [49] studied the prediction of distortions using a full-size element model, performed by ABAQUS in a 1/8 VV, which is a vacuum vessel highly used in China. To study the distortions, three different tungsten inert gas (TIG) welding sequences were simulated on this vessel.…”

Section: Position Experimental Large Distortion Theory Small Distortimentioning

confidence: 99%

Comparison of Finite Element Methods in Fusion Welding Processes—A Review

Marques

Silva

Péreira

2020

Metals

View full text Add to dashboard Cite

Currently, welding processes have become one of the most used methods for joining materials in all kinds of industries, thanks to properties such as high speed and high tensile strength. However, despite these advantages, this type of connection method has some drawbacks, for example, residual stress and structural distortion, mainly due to the process thermal cycles. Structural distortion is one of the major concerns of industrial joining practice. In order to decrease distortion, the variation of welding sequence, direction, and clamping conditions, have been applied through several years, by trial and error tests. However, numerical simulation enables virtual examination of the welding, mainly due to the progress on the numerical methods, which stimulated the research on welding simulation models. These models can cover a wide spectrum of physical and thermal processes occurring during, and after welding. The aim of this paper is to provide wider information about types of finite element method (FEM) in fusion welding processes and to demonstrate the accuracy of FEM models results compared to experimental.

show abstract

Effect of welding sequences on the welding stress and distortion in the CFETR vacuum vessel assembly using finite element simulation

Cited by 15 publications

References 21 publications

R&D achievements for vacuum vessel towards CFETR construction

R&D achievements for vacuum vessel towards CFETR construction

Methodical procedure of virtual manufacturing for analysing WAAM distortion along with experimental verification

Comparison of Finite Element Methods in Fusion Welding Processes—A Review

Contact Info

Product

Resources

About