Event: Coil Car Traveling Cylinder - To Conveyor (Extend)

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

 

1)    Proportional Directional Control Valve 339 is energized to the parallel flow pattern allowing pressurized hydraulic fluid to pass through the valve from P to A. The fluid then flows into the cap end of Coil Car Travelling Cylinder 803 causing the cylinder to extend. Note that Proportional Directional Control Valve 339 controls the extension speed of the cylinder.

2)    Exhaust fluid from the rod end of the cylinder flows through Counterbalance Valve 295. Note that this valve assembly is comprised of two sections. One section is a pressure relief valve preventing the cylinder from overpressure due to external load forces caused by the momentum of the weight of a coil. The other section consists of a pilot operated, spring-return 2-position, 2-way directional control valve. As the cylinder extends, the directional portion of this valve assembly is piloted by pilot pressure from the A-line of the circuit from a blocked flow condition to a controlled flow condition.

3)    The exhaust fluid then flows through the proportional directional, passing from B to T, then to tank through Duplex Return Line Filter 045.03.