Event: Backup Roll Balancing Cylinder - Retract (Manual Valve)

See the event “HPU – On” for previous steps in this sequence.

 

Note that this event describes the sequences for Mill Stand F1. The same sequences apply for stand F2 through F6, though the component numbers will change. Refer to the relevant schematic for each stand for the appropriate component number.

 

1)    Manually actuate 4-way Ball Valve 297.01 to the crossover flow path. Pressurized hydraulic fluid flows through the ball valve from P to B and is blocked at that port.

2)    Exhaust fluid flows from the cap end of Back Up Roll Balancing Cylinder 722.01 through the ball valve, passing from A to T, allowing the cylinder to retract.

3)    Pilot pressure flows through the shuttle valve in DIN Cartridge Valve Cover 259.01 into the spring chamber of DIN Cartridge Valve Insert 258.01, piloting the valve insert closed.

4)    Pressure Relief Valve 291.13 protects the cap end of the cylinder from overpressure.

 

Warning: The manual function must never be used during the rolling operation! This function is to be used during maintenance.