[Purposes]This paper makes cracking failure analysis of a CNG cylinder.Recommendations for avoidance of such scenario with the rest of the user's compressor cylinder were given.Besides,the ul-trasonic test and hydraulic test data of the thickness of the CNG cylinder can be used for the numerical analysis of the failure CNG cylinder.[Methods]Experimental investigation methods were employed to determine possible causes of crack occurrence and vessel rupture.Liquid penetration inspection was per-formed to check for other surface-breaking defects on the shell and locations of the cracks.Visual exami-nation revealed the condition of the internal surface of the shell.The crack was examined by an optical microscope.The electron microscope can examine and describe the fine microstructure of the crack surface at an appropriate magnification.The fine structure of the crack surface showed the defects at the starting point of the fracture.Finally,the chemical composition of the material was determined by spectral analyzer.In addition,the mechanical properties were tested.[Findings]Cylinder failed during hydraulic test.Under the condition that the test pressure was lower than the test pressure,two cracks were shown on the CNG cylinder shell,and the leakage of the test liquid occurred.[Conclusions]According to results obtained from performed investigations,it was concluded that excessive corrosion at the bottom part of the cylinder caused pits,which were served as initiation points for leakage cracks.
万方数据
维普
