SUN HYDRAULICS
QPACCAV
$185.85 USD
- SUN HYDRAULICS
- Material:QPACCAV
- Model:QPAC-CAV
- Summary:Cartridge
Quantity in stock: 0
***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 QPACCAV (Material Number: QPACCAV) is an accumulator sense, pump unload pilot valve designed to manage pressure in hydraulic systems effectively. This valve operates by sensing pressure at port 1, and once the predetermined pressure is reached, it connects port 2 to port 3 to vent a relief valve and unload the pump. It features a 30% ratio between unload setting and reset, ensuring that when the pressure falls below 70% of the set level, port 2 is blocked from port 3, allowing the pump to recharge the accumulator. A separate check valve is necessary between port 1 and the pump for optimal functionality. The QPACCAV model maintains a fixed differential ratio due to its spool design, which utilizes diameters on the spool that resist wear over time. The unit's minimum clearances between spool and sleeve, along with a sealed pilot piston diameter, minimize silting risks. A separate drain line is recommended to prevent erratic operation caused by tank line pressure fluctuations. This model requires careful consideration of adjustment range selection due to potential influences from system pressure drops and flow rates. The valve fits into a cavity type T-11A with a series 1 capacity of 46 in\u00b3/min (0.75 L/min) and can handle a maximum operating pressure of up to 5000 psi (350 bar). Its pilot flow capacity matches its series capacity at 46 in\u00b3/min (0.75 L/min). Installation requires specific torque settings: valve installation torque ranges from 30\u201335 lbf\u00b7ft (41\u201347 Nm), while locknut torque is set between 80\u201390 lbf\u00b7in (9\u201310 Nm). The QPACCAV model also incorporates Sun's floating style construction to reduce internal binding risks due to installation or machining variations.
The Sun Hydraulics QPACCAV (Material Number: QPACCAV) is an accumulator sense, pump unload pilot valve designed to manage pressure in hydraulic systems effectively. This valve operates by sensing pressure at port 1, and once the predetermined pressure is reached, it connects port 2 to port 3 to vent a relief valve and unload the pump. It features a 30% ratio between unload setting and reset, ensuring that when the pressure falls below 70% of the set level, port 2 is blocked from port 3, allowing the pump to recharge the accumulator. A separate check valve is necessary between port 1 and the pump for optimal functionality. The QPACCAV model maintains a fixed differential ratio due to its spool design, which utilizes diameters on the spool that resist wear over time. The unit's minimum clearances between spool and sleeve, along with a sealed pilot piston diameter, minimize silting risks. A separate drain line is recommended to prevent erratic operation caused by tank line pressure fluctuations. This model requires careful consideration of adjustment range selection due to potential influences from system pressure drops and flow rates. The valve fits into a cavity type T-11A with a series 1 capacity of 46 in\u00b3/min (0.75 L/min) and can handle a maximum operating pressure of up to 5000 psi (350 bar). Its pilot flow capacity matches its series capacity at 46 in\u00b3/min (0.75 L/min). Installation requires specific torque settings: valve installation torque ranges from 30\u201335 lbf\u00b7ft (41\u201347 Nm), while locknut torque is set between 80\u201390 lbf\u00b7in (9\u201310 Nm). The QPACCAV model also incorporates Sun's floating style construction to reduce internal binding risks due to installation or machining variations.
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 30% ratio between unload setting and reset; when pressure at port 1 falls below 70% 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, QCDC, 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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