Spool for one or more flow control tube only.

阀芯为一只或多只流量控制筒。

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When the control valve when the reverse, so that both fluid along the direction of movement of spool when closed, the flow control valve capacity will be increased.

当调节阀反向使用时，既流体沿着使阀芯关闭的方向流动时，调节阀的流通能力会增大。

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Adjusting mechanism is the executive body converts the output of displacement control valve spool and valve seat area change between the flow of the device.

调节机构是将执行机构的输出位移变化转换为控制阀阀芯和阀座间流通面积变化的装置。

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