SUN HYDRAULICS
QCDCLBN
$174.63 USD
- SUN HYDRAULICS
- Material:QCDCLBN
- Model:QCDC-LBN
- 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 QCDCLBN (Material Number: QCDCLBN) is an accumulator sense, pump unload pilot valve designed to efficiently manage hydraulic systems by sensing pressure in an accumulator at port 2. Once the pressure reaches the valve setting, it connects port 3 to port 4, venting a relief valve and unloading the pump. This model features a 30% ratio between unload setting and reset, ensuring that when pressure at port 2 drops below 70% of the valve setting, port 3 is blocked from port 4, allowing the pump to recharge the accumulator. It includes an integral free-flow check valve suitable for pump flows up to 12 gpm (50 L/min). For larger pumps, a different version requiring a separate check cartridge is available. This valve maintains its performance with a pressure differential between unload and reset within \u00b11% of its stated ratio, plus an additional potential increment of up to 25 psi due to dynamic seal friction. The spool design ensures consistent operation by maintaining fixed differential ratios unaffected by wear. A separate drain line is necessary for stable operation due to potential tank line pressure fluctuations. Attention should be given when selecting adjustment ranges as system pressure drops and flow rates can influence unloading valves' operation significantly. The QCDCLBN incorporates Sun's floating style construction, minimizing internal binding risk due to installation torque or machining variations. It fits into cavity T-21A with a series capacity of up to 15 gpm (60 L/min) and can operate at pressures up to 5000 psi (350 bar). The check cracking pressure is set at 4 psi (0.3 bar), with a pilot flow capacity of approximately 46 in\u00b3/min (0.75 L/min). Installation requires specific torque settings for both the valve and locknut components.
The Sun Hydraulics QCDCLBN (Material Number: QCDCLBN) is an accumulator sense, pump unload pilot valve designed to efficiently manage hydraulic systems by sensing pressure in an accumulator at port 2. Once the pressure reaches the valve setting, it connects port 3 to port 4, venting a relief valve and unloading the pump. This model features a 30% ratio between unload setting and reset, ensuring that when pressure at port 2 drops below 70% of the valve setting, port 3 is blocked from port 4, allowing the pump to recharge the accumulator. It includes an integral free-flow check valve suitable for pump flows up to 12 gpm (50 L/min). For larger pumps, a different version requiring a separate check cartridge is available. This valve maintains its performance with a pressure differential between unload and reset within \u00b11% of its stated ratio, plus an additional potential increment of up to 25 psi due to dynamic seal friction. The spool design ensures consistent operation by maintaining fixed differential ratios unaffected by wear. A separate drain line is necessary for stable operation due to potential tank line pressure fluctuations. Attention should be given when selecting adjustment ranges as system pressure drops and flow rates can influence unloading valves' operation significantly. The QCDCLBN incorporates Sun's floating style construction, minimizing internal binding risk due to installation torque or machining variations. It fits into cavity T-21A with a series capacity of up to 15 gpm (60 L/min) and can operate at pressures up to 5000 psi (350 bar). The check cracking pressure is set at 4 psi (0.3 bar), with a pilot flow capacity of approximately 46 in\u00b3/min (0.75 L/min). Installation requires specific torque settings for both the valve and locknut components.
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 30% ratio between unload setting and reset; when pressure at port 2 falls below 70% 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, QPAC, 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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