Event: Coiler Shifting Cylinder - Move In (Retract)

For previous steps in this sequence see the event “HPU – On.”

 

1)    Directional Control Valve 310.23 is energized to the parallel flow pattern allowing pressurized hydraulic fluid to pass through the valve from P to A, then through Flow Control Valve Module 178 and Check Valve 158.16 into the rod end of Coiler Shifting Cylinder 805 causing the cylinder to retract. Note that the A-port check valve in the flow control valve module forces the fluid to flow through the A-port needle valve of the module, thereby achieving meter-in speed control of the retraction speed of the cylinder.

2)    Exhaust fluid from the cap end of the flows freely through the B-port check valve of the flow control valve module, then through the directional control valve, passing from B to T, then to tank through Duplex return Line Filter 045.03.

3)    Note that due to pressure drop as the fluid flows through the circuit, the pressure on the cylinder side of Check Valve 158.15 is lower than the pressure on the opposite side of the valve, so the check valve remains closed.