SUN HYDRAULICS
QPAACBV
$201.35 USD
- SUN HYDRAULICS
- Material:QPAACBV
- Model:QPAA-CBV
- Summary:Cartridge
Due to extremely high demand, please call for availability
***Disclaimer: The following summary contains information gathered from various sources such as product descriptions, technical specifications and catalogs. While efforts have been made to provide accurate details, inaccuracies may occur. It is advised to verify all information by contacting Sun Hydraulics directly.***
The Sun Hydraulics QPAACBV (QPAACBV) is an accumulator sense, pump unload pilot valve designed to efficiently manage pressure in hydraulic systems. This valve senses pressure at port 1 and, upon reaching the preset level, connects port 2 to port 3 to vent a relief valve and unload the pump. It features a 15:1 ratio between unload setting and reset, automatically blocking port 2 from port 3 when pressure falls below 85% of the set value, thus reactivating the pump to recharge the accumulator. A separate check valve is necessary between port 1 and the pump for optimal operation. The spool design ensures a consistent differential ratio by maintaining fixed diameters that resist wear over time. Minimum clearances and a sealed pilot piston significantly decrease silting potential. The valve requires a separate drain line to prevent erratic behavior due to tank line pressure variations. With a maximum operating pressure of 5000 psi (350 bar) and a pilot flow capacity of 46 in\u00b3/min (0.75 L/min), it is crucial to carefully select an adjustment range considering system pressure drops and flows as these influence unloading performance. Installation specifications include a torque range of 30\u201335 lbf\u00b7ft (41\u201347 Nm) for the valve, with adjustments made via an internal hex screw. The Sun floating style construction minimizes internal part binding risks during installation or due to machining variations, ensuring reliable performance in demanding applications.
The Sun Hydraulics QPAACBV (QPAACBV) is an accumulator sense, pump unload pilot valve designed to efficiently manage pressure in hydraulic systems. This valve senses pressure at port 1 and, upon reaching the preset level, connects port 2 to port 3 to vent a relief valve and unload the pump. It features a 15:1 ratio between unload setting and reset, automatically blocking port 2 from port 3 when pressure falls below 85% of the set value, thus reactivating the pump to recharge the accumulator. A separate check valve is necessary between port 1 and the pump for optimal operation. The spool design ensures a consistent differential ratio by maintaining fixed diameters that resist wear over time. Minimum clearances and a sealed pilot piston significantly decrease silting potential. The valve requires a separate drain line to prevent erratic behavior due to tank line pressure variations. With a maximum operating pressure of 5000 psi (350 bar) and a pilot flow capacity of 46 in\u00b3/min (0.75 L/min), it is crucial to carefully select an adjustment range considering system pressure drops and flows as these influence unloading performance. Installation specifications include a torque range of 30\u201335 lbf\u00b7ft (41\u201347 Nm) for the valve, with adjustments made via an internal hex screw. The Sun floating style construction minimizes internal part binding risks during installation or due to machining variations, ensuring reliable performance in demanding applications.
The accumulator sense, pump unload pilot valve is used to sense pressure in an accumulator at port 1 of the valve and when the pressure at port 1 reaches the valve setting, port 2 connects to port 3 to vent a relief valve and unload the pump. This valve has a 15% ratio between unload setting and reset; when pressure at port 1 falls below 85% of the valve setting, port 2 is blocked from port 3 and the pump will come back online to recharge the accumulator. This valve requires a separate check valve between port 1 and the pump. Another version of the accumulator sense, pump unload valve, QCDA, includes a free-flow check valve for pump flows under 12 gpm (50 L/min).
- The pressure differential between unload and reset will be within +/- 1% of the stated ratio of the valve with up to an additional 25 psi (1,7 bar) due to dynamic seal friction.
- The accumulator sensing area is positively sealed.
- The spool design of this valve allows it to maintain a fixed differential ratio because the areas are created by diameters on the spool that will not wear or change with use.
- Minimum clearances between the spool and sleeve and a seal on the pilot piston diameter significantly reduce the potential for silting.
- When applying this cartridge, a separate drain line is required to prevent erratic operation caused by tank line pressure fluctuations.
- NOTE: Careful consideration should be given when selecting an adjustment range. System pressure drops and flows tend to affect the operation of unloading valves. Low operating pressures combined with low differentials result in a very narrow band between unload and reset, requiring precise system design. High flow rates typically mean high pressure drops, which subtract from the differential the valve has to work with.
- Sun has designed a variety of standard accumulator/pump unload assemblies with a variety of features. These assemblies can be found on our website under SOLUTIONS: ACCUMLATOR SENSE, PUMP UNLOAD.
- Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge machining variations.
| Cavity | T-11A |
| Series | 1 |
| Capacity | 46 in³/min.0,75 L/min. |
| Maximum Operating Pressure | 5000 psi350 bar |
| Pilot Flow Capacity | 46 in³/min.0,75 L/min. |
| Adjustment - Number of Clockwise Turns to Increase Setting | 55 |
| Valve Hex Size | 7/8 in.22,2 mm |
| Valve Installation Torque | 30 - 35 lbf ft41 - 47 Nm |
| Adjustment Screw Internal Hex Size | 5/32 in.4 mm |
| Locknut Hex Size | 9/16 in.15 mm |
| Locknut Torque | 80 - 90 lbf in.9 - 10 Nm |
| Model Weight | .35 lb0,15 kg |
| Seal kit - Cartridge | Viton: 990-011-006 |
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