Screw pump should be in suction stop valve fully open under the condition of starting, in case of overload or empty.

螺杆泵应在吸排停止阀全开的情况下起动，以防过载或吸空。

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Pump stop, they would first close the discharge stop valve, and switch to a complete halt until pump suction stop valve was closed.

泵停车时，应先关闭排出停止阀，并待泵完全停转后关闭吸入停止阀。

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