PSI - Issue 13

Gyo Geun Youn et al. / Procedia Structural Integrity 13 (2018) 1305–1311 Author name / Structural Integrity Procedia 00 (2018) 000 – 000

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Fig. 5. FE model used for the virtual test (a)full figure (b) enlarged figure of crack area

Fig. 6. FE prediction results for four-point bending pipe virtual test for unaged and aged CF8A (a) Load-LLD under monotonic loading (b) load LLD under R = 0 (c) load-LLD under R = -1 (d) comparison of crack growth behavior

4. Numerical prediction of piping system fracture behavior 4.1. Description of virtual piping system test

A pipe system with through-wall crack is applied for virtual test. The drawing for the pipe system is given ins Fig. 7. As with the four-point pipe test, the pipe system test is identical to the Battelle pipe system test except the material property. The unaged and aged CF8A (room temperature) is applied instead of A106 Gr. B (288 o C) to study the thermal ageing effect on crack growth behavior under cyclic loading condition in pipe system. The outer diameter of the pipe is 406 mm and thickness is 26 mm for all section of the pipe except elbow 4. The thickness of the elbow 4 is 41mm. The internal pressure is 15.5 MPa. Also, there exists a valve mass of 1,950 kg.