锅炉给水母管压力降低，流量骤减的原因有哪些？
参考答案：
（1）给水泵故障跳闸，备用给水泵自启动失灵。
（2）给水泵液耦内部故障。
（3）给水泵调节系统故障。
（4）给水泵出口阀故障或再循环开启。
（5）高加故障，给水旁路门未开启。
（6）给水管道破裂。
（7）除氧器水位过低或除氧器压力突降使给水泵汽化。
（8）汽动给水泵在机组负荷骤降时，出力下降或汽源切换过程中故障。
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