Repair Weld Simulation of Austenitic Steel Pipe

Bézi, Zoltán; Szávai, Szabolcs

doi:10.4028/www.scientific.net/amr.1029.194

Cited by 4 publications

(8 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results are shown for Fig. 7 Schematic presentation of the actual welding sequence of the girth (left) and repair (right) welding [4]. The pass lumping is a commonly applied procedure to simplify welding computations.…”

Section: Resultsmentioning

confidence: 98%

“…The temperature dependent material parameters for the nonlinear isotropic/kinematic hardening material model have been given in [4]. As an example, Figs.…”

Section: Introductionmentioning

confidence: 99%

“…The thermal and mechanical properties given in [4] were utilised in the computation. The thermal properties correspond to the usual properties for austenitic materials as can be found e.g.…”

Section: Introductionmentioning

confidence: 99%

“…In the thermal analysis, the actual provided MU-2 welding data [4] was utilised. The actual weld pass sequence of girth and repair welding is schematically presented in Fig.…”

Section: Introductionmentioning

confidence: 99%

“…The fabrication history of the mockup was complex, comprising [3,4]: Figure 1 shows the geometry of the girth and repair weld [5].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Computation of residual stresses for a repair weld case

Keinänen

2016

Weld World

View full text Add to dashboard Cite

The target of EU FP7 STYLE project BStructural integrity for lifetime management -non-RPV componentŵ as to improve and unify the methods of a structural integrity assessment in the ageing and lifetime management of reactor coolant pressure boundary components. One of the mock-ups in the project was manufactures from two pipes welded together. After completion of the girth weld, a deep weld repair was inserted into the girth weld. As a part of the work, roundrobin finite element computations were performed to determine residual stresses after repair welding and the computational results were compared to the deep hole drilling measurements. In this paper, the details and recomputed results of one of the analyses is presented. A part of the input data was generated with in-house codes. Sequential thermal and mechanical analyses were performed with a small strain and displacement formulation. The comparison of computed and measured temperatures and stresses shows good agreement. The computed hoop stress at the repair mid-length was higher than the axial stress. Both stresses were tensile through the wall thickness. Confidence in the results was also gained as the results were compared to those presented in the literature for a repair welding case.

show abstract

Section: Resultsmentioning

confidence: 98%

“…The temperature dependent material parameters for the nonlinear isotropic/kinematic hardening material model have been given in [4]. As an example, Figs.…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

“…In the thermal analysis, the actual provided MU-2 welding data [4] was utilised. The actual weld pass sequence of girth and repair welding is schematically presented in Fig.…”

Section: Introductionmentioning

confidence: 99%

“…The fabrication history of the mockup was complex, comprising [3,4]: Figure 1 shows the geometry of the girth and repair weld [5].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Computation of residual stresses for a repair weld case

Keinänen

2016

Weld World

View full text Add to dashboard Cite

show abstract

Finite element analysis of in-situ distortion and bulging for an arbitrarily curved additive manufacturing directed energy deposition geometry

Biegler

Marko

Graf

et al. 2018

Additive Manufacturing

View full text Add to dashboard Cite

With the recent rise in the demand for additive manufacturing (AM), the need for reliable simulation tools to support experimental efforts grows steadily. Computational welding mechanics approaches can simulate the AM processes but are generally not validated for AM-specific effects originating from multiple heating and cooling cycles. To increase confidence in the outcomes and to use numerical simulation reliably, the result quality needs to be validated against experiments for in-situ and post-process cases. In this article, a validation is demonstrated for a structural thermomechanical simulation model on an arbitrarily curved Directed Energy Deposition (DED) part: at first, the validity of the heat input is ensured and subsequently, the model's predictive quality for in-situ deformation and the bulging behaviour is investigated. For the in-situ deformations, 3D-Digital Image Correlation measurements are conducted that quantify periodic expansion and shrinkage as they occur. The results show a strong dependency of the local stiffness of the surrounding geometry. The numerical simulation model is set up in accordance with the experiment and can reproduce the measured 3-dimensional insitu displacements. Furthermore, the deformations due to removal from the substrate are quantified via 3D-scanning, exhibiting considerable distortions due to stress relaxation. Finally, the prediction of the deformed shape is discussed in regards to bulging simulation: to improve the accuracy of the calculated final shape, a novel extension of the model relying on the modified stiffness of inactive upper layers is proposed and the experimentally observed bulging could be reproduced in the finite element model.

show abstract

Development of an Elongated Ellipsoid Heat Source Model to Reduce Computation Time for Directed Energy Deposition Process

et al. 2021

View full text Add to dashboard Cite

Directed Energy Deposition (DED) Additive Manufacturing process for metallic parts are becoming increasingly popular and widely accepted due to their potential of fabricating parts of large dimensions. The complex thermal cycles obtained due to the process physics results in accumulation of residual stress and distortion. However, to accurately model metal deposition heat transfer for large parts, numerical model leads to impractical computation time. In this work, a 3D transient finite element model with Quiet/Active element activation is developed for modeling metal deposition heat transfer analysis of DED process. To accurately model moving heat source, Goldak’s double ellipsoid model is implemented with small enough simulation time increment such that laser moves a distance of its radius over the course of each increment. Considering thin build-wall of Stainless Steel 316L fabricated with different process parameters, numerical results obtained with COMSOL 5.6 Multi-Physics software are successfully validated with experiment temperature data recorded at the substrate during the fabrication of 20 layers. To reduce the computation time, elongated ellipsoid heat input model that averages the heat source over its entire path is implemented. It has been found that by taking such large time increments, numerical model gives inaccurate results. Therefore, the track is divided into several sub-tracks, each of which is applied in one simulation increment. In this work, an investigation is done to find out the correct simulation time increment or sub-track size that leads to reduction in computation time (5–10 times) but still yields sufficiently accurate results (below 10% of relative error on temperature). Also, a Correction factor is introduced that further reduces computation error of elongated heat source. Finally, a new correlation is also established in finding out the correct time increment size and correction factor value to reduce the computation time yielding accurate results.

show abstract

Repair Weld Simulation of Austenitic Steel Pipe

Cited by 4 publications

References 3 publications

Computation of residual stresses for a repair weld case

Computation of residual stresses for a repair weld case

Finite element analysis of in-situ distortion and bulging for an arbitrarily curved additive manufacturing directed energy deposition geometry

Development of an Elongated Ellipsoid Heat Source Model to Reduce Computation Time for Directed Energy Deposition Process

Contact Info

Product

Resources

About