SUN HYDRAULICS
QPADKDN
$183.87 USD
- SUN HYDRAULICS
- Material:QPADKDN
- Model:QPAD-KDN
- 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 QPADKDN (QPADKDN) is an advanced accumulator sense, pump unload pilot valve designed for precise hydraulic system management. This valve is engineered to sense pressure in an accumulator at port 1 and, upon reaching a set pressure, it connects port 2 to port 3 to vent a relief valve and unload the pump. It features a 50:1 ratio between unload setting and reset, meaning that when the pressure at port 1 falls below half of the valve setting, port 2 is blocked from port 3, allowing the pump to recharge the accumulator. Notably, this model requires a separate check valve between port 1 and the pump for optimal operation. The QPADKDN maintains its performance with minimal wear due to its spool design, which ensures fixed differential ratios by using diameters on the spool that remain unchanged over time. Additionally, it incorporates Sun's floating style construction to reduce internal part binding due to installation torque or machining variations. The valve's minimum clearances and pilot piston seal significantly lower silting risks. To prevent erratic operation from tank line pressure fluctuations, a separate drain line is necessary when applying this cartridge. The QPADKDN has a maximum operating pressure of 5000 psi (350 bar) and features a pilot flow capacity of 46 in\u00b3/min (0.75 L/min). Installation specifications include a hex size of 7/8 inch (22.2 mm) with an installation torque range of 30-35 lbf ft (41-47 Nm). For adjustments, it requires five clockwise turns to increase settings with an internal hex size adjustment screw of 5/32 inch (4 mm). The model weighs approximately .35 lb (0.15 kg) and uses Viton seal kits for durability under high-pressure conditions.
The Sun Hydraulics QPADKDN (QPADKDN) is an advanced accumulator sense, pump unload pilot valve designed for precise hydraulic system management. This valve is engineered to sense pressure in an accumulator at port 1 and, upon reaching a set pressure, it connects port 2 to port 3 to vent a relief valve and unload the pump. It features a 50:1 ratio between unload setting and reset, meaning that when the pressure at port 1 falls below half of the valve setting, port 2 is blocked from port 3, allowing the pump to recharge the accumulator. Notably, this model requires a separate check valve between port 1 and the pump for optimal operation. The QPADKDN maintains its performance with minimal wear due to its spool design, which ensures fixed differential ratios by using diameters on the spool that remain unchanged over time. Additionally, it incorporates Sun's floating style construction to reduce internal part binding due to installation torque or machining variations. The valve's minimum clearances and pilot piston seal significantly lower silting risks. To prevent erratic operation from tank line pressure fluctuations, a separate drain line is necessary when applying this cartridge. The QPADKDN has a maximum operating pressure of 5000 psi (350 bar) and features a pilot flow capacity of 46 in\u00b3/min (0.75 L/min). Installation specifications include a hex size of 7/8 inch (22.2 mm) with an installation torque range of 30-35 lbf ft (41-47 Nm). For adjustments, it requires five clockwise turns to increase settings with an internal hex size adjustment screw of 5/32 inch (4 mm). The model weighs approximately .35 lb (0.15 kg) and uses Viton seal kits for durability under high-pressure conditions.
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 50% ratio between unload setting and reset; when pressure at port 1 falls below 50% 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, QCDD, 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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