自吸式水泵第一次使用时，需要加引水，以后则不必再加引水。

Self suction pump is used for the first time, need to add water, then don't need to add water.

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洒水车配备的是离心式洒水泵，该泵每次吸水前，必须向水泵内加入一定量的引水，加完后必须关闭加水口。

Sprinkler is equipped with a centrifugal pump, the pump every time before water, must be added to a certain amount of water to the pump, plus the need to close the water inlet.

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如水泵安装在进水水位以上时，为了灌泵启动，一般可装底阀，也可采用真空泵引水的方法。

In general, a foot valve can be mounted if the pump is mounted above the water level of the water inlet so as to start the pump with priming, it can also use the way of vacuum pump water leading.

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