超超临界机组轴封供汽系统参数研究和抱轴问题分析

Research on Gland Steam Parameters and Analysis of Gland Seizing Shaft for Ultra-supercritical Turbine

对在役超超临界机组发生抱轴现象进行了实际运行调研分析,得出轴封温度低是抱轴事故发生的主要原因;同时对轴封系统不同供汽温度进行稳态和非稳态模拟计算,得出机组轴封间隙设计合理,但要保证轴封系统不碰摩,轴封温度应保证在260℃以上,如果轴封供汽温度低于260℃时,应放慢轴封母管开启速度。研究结论为避免抱轴现象提供了理论依据。

Low gland steam temperature is the main reason for the accident of gland seal seizing shaft by investigation and analysis of operating data of Uhra-supercritical turbine when gland seal seizing shaft happens. Steady and transient calculation for different gland steam temperature show gland gap design of unit is reasonable. If gland steam temperature is more than 260℃ Rubbing of the gland seal system will not happen;If not, the opening speed of gland mother pipe should slow down. Research conclusions provide theoretical basis for avoiding gland seal seizing shaft.