低压加热器疏水泵故障分析与选型要点

Fault Analysis and Key Points of Selection Essentials Discussion for Low Pressure Heater Drainage Pump

低压加热器疏水泵故障率较高,分析其主要原因为汽蚀余量不足、运行工况不稳定与加工制造缺陷,并提出相应的处理对策。结合实际工程,介绍了泵型、轴封型式、冲洗方案的确定要点,采用变频控制与出口调节阀相结合、轴封采用机械密封配外部冲洗液的选型方案,实际运行效果良好,可为已有项目改造与新建项目中低压加热器疏水泵的选型设计提供参考。

Aiming at the problem of high failure rate of low pressure drainage pump in operation,the causes are analyzed and insufficient cavitation margin,unstable operating conditions and manufacturing defects are determined to be the main causes.Furthermore,corresponding countermeasures are provided.Based on the actual engineering project,the key points of the pump type determination,shaft seal type and flushing plan are introduced.The selection scheme that uses frequency conversion control combined with the outlet regulating valve,and the mechanical seal with external flushing liquid is adopted and proved to have a good running effect,which could be referred by modification in existed projects and new-built project.