Structural Analysis of Metallic Pressure Vessels With Weld Sinkage in the Circumferential Joint
Abstract
The presence of weld sinkage in cir-seam joint of pressure vessels (cylindrical and spherical) has been investigated in this work. The discontinuity considered here is named as weld sinkage. The corresponding discontinuity stress introduced during fabrication process is analysed. Here only geometric aspects are being considered and the discontinuities are assumed to be free of residual stress. Non-linear finite element analysis (NL-FEA) performed. The vessel material of HSLA 15CDV6 is considered. Graphically the deformations and stress distributions( meridional, hoop and effective) along axial distance are shown. The effective (von-Mises) stress is found at sinkage location around 2 and 4 times higher than nominal stress( stress away from sinkage location) for cylindrical and spherical vessel respectively.
Keywords
Circumferential joint , finite element analysis , weld sinkage , Nonlinear analysis , Pressure vessels
Kaynakça
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