Event: Mandrel Support Bearing Cylinders - Open (Retract)

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

 Due to the weight of the finished coil and load forces, the Operator Side of the Coiler Mandrel needs to be supported during coiling by a support bearing, but the bearing halves need to be pivoted away after coiling to allow removal of the finished coil from the mandrel.

1)    Directional Control Valve 317 is energized to the crossover flow pattern allowing pressurized hydraulic fluid to pass through the valve from P to B and then into the rod ends of Mandrel Support Bearing Cylinders 806.01 and 806.02 causing the cylinders to retract.

2)    Exhaust fluid from the cap end of each cylinder flows through Rectifier Plates 160.01 and 160.02 and Flow Control Valves 186.05 and 186.06. The check valves in the rectifier plates are arranged so that they direct the fluid to flow in only one direction through the flow control valves. Using compass directions, the exhaust fluid is blocked by the NW check valve, thereby forcing the fluid to flow through the NE valve. Next, the SE check valve forces the fluid to flow through the flow control valve, from right to left in the schematic. The check valve which is part of the flow control valve forces the fluid to be metered by the flow control valve, achieving meter-out speed control of the retraction speed of the cylinders.