SUN HYDRAULICS
QCDDCAN
$182.57 USD
- SUN HYDRAULICS
- Material:QCDDCAN
- Model:QCDD-CAN
- 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 QCDDCAN (Material Number: QCDDCAN) is an accumulator sense, pump unload pilot valve designed to optimize hydraulic system efficiency by managing the pressure in an accumulator. This valve operates by sensing pressure at port 2, and when the pressure reaches the preset level, it connects port 3 to port 4 to vent a relief valve and unload the pump. It features a 50% ratio between unload setting and reset, meaning that when the pressure falls below half of the valve setting, port 3 is blocked from port 4, allowing the pump to recharge the accumulator. With an integral free-flow check valve suitable for pump flows up to 12 gpm (50 L/min), this model is ideal for applications requiring precise control of hydraulic flow and pressure. The QCDDCAN ensures a fixed differential ratio due to its spool design, which maintains consistent performance over time without wear-induced changes. It has minimum clearances between spool and sleeve, along with a seal on the pilot piston diameter to reduce silting potential. A separate drain line is necessary for operation to avoid erratic behavior caused by tank line pressure fluctuations. The design incorporates Sun's floating style construction, minimizing internal binding risks due to installation torque or machining variations. This cartridge fits into a T-21A cavity with a series 1 capacity of up to 15 gpm (60 L/min) and can handle maximum operating pressures of 5000 psi (350 bar). Additional specifications include a check cracking pressure of 4 psi (0.3 bar) and a pilot flow capacity of 46 in\u00b3/min (0.75 L/min). The adjustment requires up to five clockwise turns to increase settings, with specific torque requirements for installation and adjustments provided for optimal performance.
The Sun Hydraulics QCDDCAN (Material Number: QCDDCAN) is an accumulator sense, pump unload pilot valve designed to optimize hydraulic system efficiency by managing the pressure in an accumulator. This valve operates by sensing pressure at port 2, and when the pressure reaches the preset level, it connects port 3 to port 4 to vent a relief valve and unload the pump. It features a 50% ratio between unload setting and reset, meaning that when the pressure falls below half of the valve setting, port 3 is blocked from port 4, allowing the pump to recharge the accumulator. With an integral free-flow check valve suitable for pump flows up to 12 gpm (50 L/min), this model is ideal for applications requiring precise control of hydraulic flow and pressure. The QCDDCAN ensures a fixed differential ratio due to its spool design, which maintains consistent performance over time without wear-induced changes. It has minimum clearances between spool and sleeve, along with a seal on the pilot piston diameter to reduce silting potential. A separate drain line is necessary for operation to avoid erratic behavior caused by tank line pressure fluctuations. The design incorporates Sun's floating style construction, minimizing internal binding risks due to installation torque or machining variations. This cartridge fits into a T-21A cavity with a series 1 capacity of up to 15 gpm (60 L/min) and can handle maximum operating pressures of 5000 psi (350 bar). Additional specifications include a check cracking pressure of 4 psi (0.3 bar) and a pilot flow capacity of 46 in\u00b3/min (0.75 L/min). The adjustment requires up to five clockwise turns to increase settings, with specific torque requirements for installation and adjustments provided for optimal performance.
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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