Abstract: Abstract:In a 600MW unit, the opening of the water inlet adjusting valve on the deaerator changed rapidly due to serious reduction of the condensate water flow, the automatic water level adjustment function had not been realized, and the positioner was damaged repeatedly due to the highfrequency vibration of the pipeline. The reasons of vibration of the condensate pipeline were analyzed. The reformation scheme was proposed. After the reformation, the rapid change fault of the opening of the water inlet adjustment valve caused by reduction of the condensate water flow did not occur again, and the highfrequency vibration of the pipeline was eliminated.

Key words: Key words:variation of condensate water flow, rapid change of water inlet valve opening, pipeline vibration, reformation scheme, positioner type replacement