某热电厂600 MW锅炉水冷壁管在水压试验时出现开裂。采用宏观分析、化学成分分析、金相检验、力学性能试验等方法对开裂原因进行了分析。结果表明：水冷壁管原始管材边角部位存在夹渣缺陷，使得母材形成不连续缺陷，在水压试验升压时，裂纹扩展最终导致管子开裂失效。

The water wall tube of a 600 MW boiler in a thermal power plant cracked during the hydraulic test. The causes of cracking were analyzed by means of macro analysis, chemical composition analysis, metallographic examination and mechanical property test. The results show that there were slag inclusion defects in the corner of the original tube, which made the base metal form discontinuous defects. When the pressure was increased during the hydrostatic test, the crack propagation eventually led to the cracking failure of the tube.