汽轮机真空严密性在机组经济、安全运行中发挥着至关重要的作用。鹤煤热电厂#1汽轮机组因为真空严密性不合格,导致供电煤耗增加了3.5g/kwh,机组发电成本大幅上升。通过对引起严密性降低的原因及其故障特征进行分析,并对真空漏点查找工艺进行选择,经过汽侧灌水、氦气找漏等一系列方法,找到了真空系统存在的漏点。经过处理后,真空下降速度由原先的0.96kPa/min降低至0.27kPa/min,真空系统恢复正常。 Turbine vacuum tightness plays a crucial role in economy and safe operation of the unit. The # 1 turbines in Hebi Thermal Power Plant failed the vacuum tightness, resulting in an increase of 3.5 g / kWh in power supply and coal consumption. The power generation cost of the unit increased sharply. By analyzing the causes of the tightness reduction and the characteristics of the faults, and selecting the process of finding the vacuum leak point, the leak of the vacuum system was found through a series of methods such as steam-side irrigation and helium leak detection. After treatment, the rate of vacuum drop from the original 0.96kPa / min reduced to 0.27kPa / min, the vacuum system returned to normal.