SUN HYDRAULICS
QCDDKAN
$188.53 USD
- SUN HYDRAULICS
- Material:QCDDKAN
- Model:QCDD-KAN
- 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 QCDDKAN (Material Number: QCDDKAN) is an accumulator sense, pump unload pilot valve engineered to monitor and manage pressure within an accumulator system. When the pressure at port 2 reaches the preset valve setting, this valve facilitates a connection between port 3 and port 4, venting a relief valve to unload the pump. The integral free-flow check valve is optimized for pump flows up to 12 gpm (50 L/min); for higher capacity needs, consider the QPAD model which accommodates a separate check cartridge. A key feature of this valve is its fixed differential ratio of 50% between unload setting and reset, ensuring consistent performance with minimal wear due to its spool design. The pressure differential accuracy is maintained within 1% of the stated ratio, with dynamic seal friction potentially adding up to an additional 25 psi (1.7 bar). The design includes a positively sealed accumulator sensing area and minimizes silting risk through precise spool and sleeve clearances. To ensure stable operation, a separate drain line is recommended to counteract tank line pressure fluctuations. Users should carefully select adjustment ranges as system pressure drops and flow rates can influence unloading operations; low operating pressures necessitate precise system design due to narrow bands between unload and reset points. This model fits into cavity T-21A, Series 1 with a capacity of up to 15 gpm (60 L/min) and can withstand maximum operating pressures of 5000 psi (350 bar). It features a check cracking pressure of 4 psi (0.3 bar) with specific installation torque requirements for optimal performance. The product\u2019s floating style construction mitigates risks associated with internal part binding from excessive torque or machining variations during installation.
The Sun Hydraulics QCDDKAN (Material Number: QCDDKAN) is an accumulator sense, pump unload pilot valve engineered to monitor and manage pressure within an accumulator system. When the pressure at port 2 reaches the preset valve setting, this valve facilitates a connection between port 3 and port 4, venting a relief valve to unload the pump. The integral free-flow check valve is optimized for pump flows up to 12 gpm (50 L/min); for higher capacity needs, consider the QPAD model which accommodates a separate check cartridge. A key feature of this valve is its fixed differential ratio of 50% between unload setting and reset, ensuring consistent performance with minimal wear due to its spool design. The pressure differential accuracy is maintained within 1% of the stated ratio, with dynamic seal friction potentially adding up to an additional 25 psi (1.7 bar). The design includes a positively sealed accumulator sensing area and minimizes silting risk through precise spool and sleeve clearances. To ensure stable operation, a separate drain line is recommended to counteract tank line pressure fluctuations. Users should carefully select adjustment ranges as system pressure drops and flow rates can influence unloading operations; low operating pressures necessitate precise system design due to narrow bands between unload and reset points. This model fits into cavity T-21A, Series 1 with a capacity of up to 15 gpm (60 L/min) and can withstand maximum operating pressures of 5000 psi (350 bar). It features a check cracking pressure of 4 psi (0.3 bar) with specific installation torque requirements for optimal performance. The product\u2019s floating style construction mitigates risks associated with internal part binding from excessive torque or machining variations during installation.
The accumulator sense, pump unload pilot valve is used to sense pressure in an accumulator at port 2 of the valve and when the pressure at port 2 reaches the valve setting, port 3 connects to port 4 to vent a relief valve and unload the pump. This valve has a 50% ratio between unload setting and reset; when pressure at port 2 falls below 50% of the valve setting, port 3 is blocked from port 4 and the pump will come back online to recharge the accumulator. The integral free-flow check valve is suitable for pump flows up to 12 gpm (50 L/min). For higher capacity pumps, another version of accumulator sense, pump unload cartridge, QPAD, which requires a separate check cartridge is available.
- 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-21A |
| Series | 1 |
| Capacity | 15 gpm60 L/min. |
| Maximum Operating Pressure | 5000 psi350 bar |
| Check Cracking Pressure | 4 psi0,3 bar |
| Pressure Drop, Port 1 to Port 2 | 100 psi@15 gpm7 bar@60 L/min. |
| 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: 990-021-006 |
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