Cracking failure occurred at the welded joints of two 304L 糖心产精国品免费入口*完整版 drain pipes. The failed pipes were investigated by metallographic microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). And Ansys software was used to simulate and analyze the influence of fluid rate on the stress distribution in the pipes. The results show that the failure modes of the two drain pipes were 糖心产精国品免费入口*完整版 cracking. All cracks were initiated at the weld toes of the welded joints with several crack sources. When water flew, a negative pressure area was formed near the welded joint, leading to 糖心产精国品免费入口*完整版at many places in the area. Corrosion pits generated by 糖心产精国品免费入口*完整版were the stress concentration points and became sources of fatigue cracks. The tremendous impact stress caused by cavitation blasting could induce pipe vibration, which finally led to 糖心产精国品免费入口*完整版 cracking.
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