SUN HYDRAULICS
QCDBLCV
$186.55 USD
- SUN HYDRAULICS
- Material:QCDBLCV
- Model:QCDB-LCV
- 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 QCDBLCV (QCDBLCV) is an advanced accumulator sense, pump unload pilot valve designed to optimize hydraulic system efficiency. This valve is engineered to sense pressure in an accumulator at port 2 and, upon reaching the set pressure, connects port 3 to port 4 to vent a relief valve and unload the pump. It features a 20:1 ratio between unload setting and reset, ensuring that when the pressure at port 2 drops below 80% of the valve setting, port 3 is blocked from port 4, allowing the pump to recharge the accumulator. The integral free-flow check valve accommodates pump flows up to 15 gpm (60 L/min), making it suitable for various applications. For higher capacity pumps, an alternative model requiring a separate check cartridge is available. This valve maintains a fixed differential ratio due to its spool design with diameters that resist wear over time. The precise engineering minimizes potential silting through close clearances and a sealed pilot piston diameter. A separate drain line is necessary to prevent erratic operation due to tank line pressure fluctuations. Users should carefully select an adjustment range as system pressure drops and flow rates can significantly affect unloading valves' performance. The QCDBLCV incorporates Sun's floating style construction, reducing risks of internal binding caused by excessive installation torque or cavity machining variations. With maximum operating pressure up to 5000 psi (350 bar) and specific installation requirements like torque settings for locknut and adjustment screw sizes, this valve ensures reliable operation in demanding environments. Its compact design with a weight of .35 lb (.15 kg) makes it suitable for integration into various hydraulic systems where precision and reliability are paramount.
The Sun Hydraulics QCDBLCV (QCDBLCV) is an advanced accumulator sense, pump unload pilot valve designed to optimize hydraulic system efficiency. This valve is engineered to sense pressure in an accumulator at port 2 and, upon reaching the set pressure, connects port 3 to port 4 to vent a relief valve and unload the pump. It features a 20:1 ratio between unload setting and reset, ensuring that when the pressure at port 2 drops below 80% of the valve setting, port 3 is blocked from port 4, allowing the pump to recharge the accumulator. The integral free-flow check valve accommodates pump flows up to 15 gpm (60 L/min), making it suitable for various applications. For higher capacity pumps, an alternative model requiring a separate check cartridge is available. This valve maintains a fixed differential ratio due to its spool design with diameters that resist wear over time. The precise engineering minimizes potential silting through close clearances and a sealed pilot piston diameter. A separate drain line is necessary to prevent erratic operation due to tank line pressure fluctuations. Users should carefully select an adjustment range as system pressure drops and flow rates can significantly affect unloading valves' performance. The QCDBLCV incorporates Sun's floating style construction, reducing risks of internal binding caused by excessive installation torque or cavity machining variations. With maximum operating pressure up to 5000 psi (350 bar) and specific installation requirements like torque settings for locknut and adjustment screw sizes, this valve ensures reliable operation in demanding environments. Its compact design with a weight of .35 lb (.15 kg) makes it suitable for integration into various hydraulic systems where precision and reliability are paramount.
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 20% ratio between unload setting and reset; when pressure at port 2 falls below 80% 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 15 gpm (60 L/min). For higher capacity pumps, another version of accumulator sense, pump unload cartridge, QPAB, 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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