Installations with suction lift require a good quality foot valve to avoid loss of prime - remove in-built check valve.

进水口的安装需要使用一个品质优良的底阀，以避免进水口压力损失- 拆除内置式止回阀。

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All Stenner metering pumps have a 3-point roller design in the pump head, which ACTS as a check valve to prevent back flow, siphoning, overdosing and loss of prime.

泵头有3点滚筒设计，设备可作为止回阀阻止回流，虹吸，过量用药和避免大量的材料损失等。

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