汽轮机真空系统漏空原因及提高严密性的措施

A Research of the Causes of the Vacuum Leak in Steam Turbine and of Measures of Improvement

利用氦质谱检漏仪对徐州发电厂的汽轮机组进行真空严密性检测.分析发现低压防爆门泄漏、低压汽封径向间隙偏大及汽缸严密性能差是造成汽轮机真空系统漏空的主要原因.针对以上问题对机组真空系统的密封情况进行了改进.跟踪调查显示,改进后的真空系统的严密性有了大幅度提高.

We had measured the vacuum tightness of the steam turbine group of Xuzhou Power Plant through a helium mass spectrum leak detector. And we found out that the major causes of vacuum leak lied in a leakage in the low--pressure explosion--proof door, a bigger low--pressure vapor seal radial clearance, and the low tightness of the cylinder. Hence, we made some improvements aiming at the above problems, and as demonstrated in a following test, the vacuum tightness had been greatly improved.