Drop in vacuum of the turbine air cooler

The vacuum level of the turbine surface cooler is crucial for preventing the unit from shutting down due to interlocks, and it has a significant impact; it is recommended to check the following aspects one by one: First, if the temperature of the circulating water used in the surface cooler is high or its flow rate is low. At this time, contact the production scheduler to lower the circulating water temperature or increase the amount of circulating water used. Second, if the leakage from the turbine seal increases, the leakage point should be inspected and addressed. Third, if the primary and secondary vacuum ejectors are faulty and result in insufficient pumping capacity, the vacuum ejectors should be repaired. Fourth, if the water seal of the atmospheric safety valve is damaged, a water seal should be installed. Fifth, the liquid level in the surface condenser is high; the discharge volume of the condensed liquid should be increased. In short, it is necessary to inspect all the associated auxiliary equipment, instruments, pipelines, valves, etc., – by doing so, the cause can definitely be identified.

Is there enough water in the atmospheric safety valve?

Besides the data you mentioned, there’s also the issue of whether there is sufficient water in the atmospheric safety valve How is the performance of the extractor? How about the shaft seal steam? Is the smoke from the signal tube significant enough? Vapor pressure and temperature of the extractor? Finally, there are leaks at the flanges connected to the vacuum system

Thank you very much. Everything mentioned above is fine; there are no issues. I checked it several times, and ultimately it was determined that there is a problem with the control oil circuit

Thank you very much. The final diagnosis was that there is a problem with the oil control circuit

What’s the issue with the control oil circuit? How could he affect a vacuum? Learn about it*

Oh, I’m sorry, I replied incorrectly. It’s a problem related to the speed control valve, the control oil circuit

What the poster means is: controlling the fluctuations in oil level to prevent fluctuations in the speed control valve, and then the decrease in vacuum caused by changes in steam volume? Is it that impactful? Wasn’t the steam flow rate checked during the previous inspections? Another question: Since the exhaust pressure has changed by so much, why hasn’t the exhaust temperature changed?

The final conclusion of the management was that the oil filter was clogged, which led to a drop in oil pressure and an inability to generate the pressure required to open the speed control valve