The circuit shows a counterbalance valve CB in series with a standard pilot-to-open check valve CK on the cylinder rod end and a second counterbalance valve on the full bore end of the cylinder.
- Load-sensitive counterbalance: CB**
- Pilot-to-open check: CK*B, CKCR (5:1)
Benefits of this circuit arrangement:
- The cylinder is an outrigger that lifts and stabilizes a vehicle. The weight of the rod and attachment is low so the setting of the counterbalance valve can be low. This allows the lowering of the outrigger at low inlet pressures.
- When the vehicle is driven on bumpy roads, the outriggers must be kept in the retracted position regardless of pressure spikes that are incurred. The pilot check offers this function.
- The counterbalance valve on the piston side keeps the vehicle off the ground in the extended condition of the cylinder. The cylinder must also remain in a safe position in the event of a piston seal failure. This requires a counterbalance to be set above the maximum expected pressure that can be generated by the rod‘s area inside the cylinder.
For Sun technical support, contact Bernhard Kristen.
