采用化学成分分析、金相显微、能谱、X射线衍射和电化学等手段对某煤矿液压支架油缸内孔腐蚀失效件进行了检测分析。结果表明：该油缸内表面的腐蚀以点蚀为主，腐蚀产物中含有一定量的S元素；该矿配液水质和液压液浓度均不符合MT76-2002标准要求，油缸内表面的点蚀是由液压液使用不当造成的。

Chemical analysis, metallurgycal microscopy, energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and dynamic potential polarization curve were used to investigate the internal surface corrosion of hydraulic cylinder of a hydraulic powered roof support. The results indicated that pitting corrosion occurred on the internal surface of hydraulic cylinder, and the element S was detected in the corrosion products. The concentration of the hydraulic fluid and the water used to prepare the hydraulic fluid did not meet the requirements of MT76-2002. The pitting was caused by the improper usage of hydraulic fluids.