Abstract:

Stable temperature of shaft seal steam is very important for safe operation of steam turbine. Analyzing the abnormal temperature fluctuation of shaft seal steam in a steam turbine, it is pointed out that the change of steam temperature is due to the change of steam flow which results from the deviation of pressure measurement point. It further causes the movement of uneven steam mixed flow area and affects the measuring accuracy of steam flow temperature.Measures such as adjusting the pressure measuring point of the lowpressure shaft seal steam and reducing the set value of the inlet pressure of the lowpressure shaft seal steam are proposed, which effectively solves the problem of temperature fluctuation of the shaft seal steam.

Key words:

steam turbine, shaft seal steam, temperature fluctuation, pressure measurement point