Figure 1.9 shows a meter-out circuit for flow control during the extend stroke. When the cylinder extends, the flow coming from the pump into the cylinder is not controlled directly. However, the flow out of the cylinder is controlled using the flow-control valve (metering orifice). On the other hand, when the cylinder retracts, the flow passes through the check valve unopposed, bypassing the needle valve. Thus, only the speed during the extend stroke is controlled.
Both the meter-in and meter-out circuits mentioned above perform the same operation (control the speed of the extending stroke of the piston), even though the processes are exactly opposite to one another.
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