Measurement and Analysis of Residue Stresses Conditions in High Pressure Gas Cylinder

This article attempts to analyze systematically the residue stress issue in high pressure gas cylinder used for compressed natural gas by studying the residue stress condition of the cylinders during their manufacturing process until they are put into service. The residue stresses conditions were tracked throughout the process of fabrication of a high-pressure gas cylinder. Residual surface stresses were measured at the same locations in gas cylinder by X-ray diffraction after gas cylinder was forged, quenched and tempered. Additionally, stress conditions were tested by metal magnetic memory method in order to execute early diagnostics of the inspection object before each X-ray diffraction tested. There is a comparison of two kinds methods. As a result, residual stresses were decreased after gas cylinder was heat treatment. The maximum value of residual stresses in gas cylinder was less than 0.17sigmas after tempering, and stress condition in all the gas cylinder were uniformity and it is shown that heat treatment made good effect.