SUN HYDRAULICS
QCDCLAV
$183.57 USD
- SUN HYDRAULICS
- Material:QCDCLAV
- Model:QCDC-LAV
- 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 QCDCLAV (Material Number: QCDCLAV) is an accumulator sense, pump unload pilot valve designed to manage hydraulic systems efficiently by sensing pressure at port 2. When the pressure at this port reaches the valve's set threshold, the valve connects port 3 to port 4, venting a relief valve and unloading the pump. This model features a 30:1 ratio between unload and reset settings, with the pump reactivating to recharge the accumulator when pressure drops below 70% of the set value. The integral free-flow check valve accommodates pump flows up to 12 gpm (50 L/min), while higher capacity pumps may require a separate check cartridge version, QPAC. The valve maintains a precise differential ratio due to its spool design, which prevents wear over time. It minimizes silting through tight clearances and sealed pilot piston diameters. A separate drain line is essential for stable operation, avoiding issues from tank line pressure fluctuations. Users should carefully select adjustment ranges considering system pressures and flow rates; low pressures or high flow rates can affect operational precision due to narrow differential bands. The QCDCLAV features Sun's floating style construction, reducing risks of internal part binding from installation torque or machining variations. It fits cavity T-21A with a series 1 capacity of up to 15 gpm (60 L/min) and operates under maximum pressures of 5000 psi (350 bar). The check cracking pressure is set at 4 psi (0.3 bar), with a minimal pressure drop from port 1 to port 2 at specified flow rates. Additional specifications include adjustment capabilities via clockwise turns, specific torque requirements for installation and locknut tightening, and compatibility with Viton seal kits for robust performance in demanding applications.
The Sun Hydraulics QCDCLAV (Material Number: QCDCLAV) is an accumulator sense, pump unload pilot valve designed to manage hydraulic systems efficiently by sensing pressure at port 2. When the pressure at this port reaches the valve's set threshold, the valve connects port 3 to port 4, venting a relief valve and unloading the pump. This model features a 30:1 ratio between unload and reset settings, with the pump reactivating to recharge the accumulator when pressure drops below 70% of the set value. The integral free-flow check valve accommodates pump flows up to 12 gpm (50 L/min), while higher capacity pumps may require a separate check cartridge version, QPAC. The valve maintains a precise differential ratio due to its spool design, which prevents wear over time. It minimizes silting through tight clearances and sealed pilot piston diameters. A separate drain line is essential for stable operation, avoiding issues from tank line pressure fluctuations. Users should carefully select adjustment ranges considering system pressures and flow rates; low pressures or high flow rates can affect operational precision due to narrow differential bands. The QCDCLAV features Sun's floating style construction, reducing risks of internal part binding from installation torque or machining variations. It fits cavity T-21A with a series 1 capacity of up to 15 gpm (60 L/min) and operates under maximum pressures of 5000 psi (350 bar). The check cracking pressure is set at 4 psi (0.3 bar), with a minimal pressure drop from port 1 to port 2 at specified flow rates. Additional specifications include adjustment capabilities via clockwise turns, specific torque requirements for installation and locknut tightening, and compatibility with Viton seal kits for robust performance in demanding applications.
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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