PSI - Issue 60

Rohan Nair et al. / Procedia Structural Integrity 60 (2024) 93–114 Rohan Nair / Structural Integrity Procedia 00 (2023) 000–000

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Fig. 17: SEM fracture image of tensile tested specimen. The micrograph in the inset shows the fracture surface at low magnification

4.2.

Proof Pressure Test:

The peak strain values (hoop and meridional) recorded in critical strain gauge locations versus the predicted strains during proof pressure test is shown in fig.18 and 19. The test article withstood the proof pressure test without any global yielding and the peak strain values achieved were benign and under the marginal limits. The strain gauge S32-M which is at RW1 location of the circumferential weld showed a peak strain value of 1500 µs, with a residual strain of 1100 µs. Post proof pressure test DP and RT results were satisfactory and showed no signs of crack or weld distortion. MSLD leak test results achieved were under the maximum specified value. The test article qualified the acceptance tests and was cleared for further qualification tests.

Fig. 18: Predicted versus actual hoop strains obtained during the proof pressure test.