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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Use a pressure reducing regulator or separate control valve to safely discharge gas from cylinders. Use a check valve to prevent reverse flow into the cylinder.

使用减压调整器或单个的控制阀来安全地从钢瓶中排出气体。采用止回阀，防止回流入钢瓶。

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However, the need for oil flow in hydraulic circuit reverse flows can use hydraulic control, opening a one-way valve, so that the flow of oil can flow in both directions.

但在液压回路中需要油流反向流动时又可利用控制油压，打开单向阀，使油流在两个方向都可流动。

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