PSI - Issue 41

Chouaib Zeghida et al. / Procedia Structural Integrity 41 (2022) 384–393

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Zeghida Chouaib et al. / Structural Integrity Procedia 00 (2022) 000–000

The major inputs related to the geometry of the pipe, the pipe material, and the operating conditions are described below (Table1). Plant lifetime of 40 years is simulated and results are printed at two-year intervals. The maximum time step for stress corrosion crack growth is limited to 0.1 years, meaning that even during long periods of steady-state operation; crack site, stress intensity factors, and other calculations are updated every 0.1 year. Residual stresses are considered in the analysis. 5. Results and Discussion 5.1. Results without IHSI In this section, a finite element residual stress analysis of IASI304 stainless steel pipe (interior diameter of 300 mm, wall thickness of 30 mm) was conducted for girth welding and welding plus IHSI treatment in the next section using ANSYS 20R2. Material constants used in the analyses are shown in Figure 4. These values are obtained from (Liu, 2021).The same material constants are used for the weld material and the heat-affected zone. After completing the simulation of the pipe butt welding, residual stresses are established.

Fig. 4. Material parameters of 304 stainless steel: (a) Physical parameters; (b) Mechanical parameters (Liu et al., 2021).

The polynomial fitted residual stresses data can be used to calculate cumulative leak probability using M PRAISE are shown in Figure 5.

Fig. 5. Axial residual stress distribution versus the wall thickness after welding and IHSI for Uncracked pipe.