Cause Analysis of Condensate Pump Output Decreasing

Condensate pumps are important auxiliary machinery in the steam-water cycle of thermal power plants and assume the task of pumping condensate from condenser hot water wells to deaerators. If the condensate pump can not work properly, the condensed water in the hot water well can not be pumped to the deaerator, the steam and water cycle of the thermal power plant will be destroyed and the unit will be forced to stop. As the condensate pump works under the condition of high vacuum, if the negative pressure part of the equipment and piping system is not sealed, it can easily leak into the air and affect the normal operation of the pump. From the condensate pump structure and its water system analysis, the pump output decreased due to the possible reasons are: (1) Centrifugal pump inlet filter plugging; (2) into the water pipe or vacuum balance pipe leakage of air; (3) standby pump (4) impeller, key damage or runner blockage; (5) mouth ring gap, internal reflux; (6) magnetic pump motor two-phase operation; (7) hot well water level Low; (8) backup pump outlet check valve is not strict; (9) pump body and pump cylinder (also called wells) flange leak air. Because A condensate pump output decreased 4 days after the start of the pump, and two pumps in the double pump outlet pressure are slightly higher than the rated value, can be ruled out the above factors 4,5,6,8. In addition, the centrifugal pump hot well water level alarm signal is directly removed because of its low water level condensate pump output decline set conditions.