SUN HYDRAULICS
RELIEF CART
RDFALBN
$84.60
- SUN HYDRAULICS
- Material:RDFALBN
- Model:RDFA-LBN
- Summary:Cartridge
Quantity in stock: 6
***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 RDFALBN (RDFALBN) is a direct-acting relief cartridge valve designed to protect hydraulic components from pressure transients by functioning as a normally closed, pressure-limiting valve. When the inlet port pressure reaches the set threshold, the valve opens to tank port 2, throttling flow to manage and limit pressure rise, ensuring smooth and quiet operation with essentially zero leakage. It is dirt tolerant, immune to silting, and provides rapid response times. This relief cartridge is interchangeable with other 2-port relief cartridges of similar frame size and flow path. It can handle maximum pressure at port 2, making it suitable for cross port relief circuits and load holding applications. The adjustment process requires system pressure removal due to seal exposure on the adjust screw; adjustments should be made within midrange to high spring settings for optimal repeatability. The valve's performance remains stable despite varying oil temperatures or contamination levels. The RDFALBN features a cavity T-3A series 2 configuration with a capacity of up to 50 gpm (200 L/min) and operates at a maximum pressure of 5000 psi (350 bar). Its typical response time is around 2 milliseconds with a maximum leakage rate of 10 drops/minute upon reseat at 90% of the setting. Installation specifications include a valve hex size of 1-1/8 inches (28.6 mm) and an installation torque range of 45-50 lbf ft (61-68 Nm). The adjustment screw has an internal hex size of 5/32 inches (4 mm), while the locknut hex size is 9/16 inches (15 mm) with locknut torque ranging from 80-90 lbf in (9-10 Nm). Weighing approximately .50 lb (.25 kg), this valve incorporates Sun's floating style construction to prevent internal part binding due to excessive installation torque or machining variations in cavity/cartridge interfaces.
The Sun Hydraulics RDFALBN (RDFALBN) is a direct-acting relief cartridge valve designed to protect hydraulic components from pressure transients by functioning as a normally closed, pressure-limiting valve. When the inlet port pressure reaches the set threshold, the valve opens to tank port 2, throttling flow to manage and limit pressure rise, ensuring smooth and quiet operation with essentially zero leakage. It is dirt tolerant, immune to silting, and provides rapid response times. This relief cartridge is interchangeable with other 2-port relief cartridges of similar frame size and flow path. It can handle maximum pressure at port 2, making it suitable for cross port relief circuits and load holding applications. The adjustment process requires system pressure removal due to seal exposure on the adjust screw; adjustments should be made within midrange to high spring settings for optimal repeatability. The valve's performance remains stable despite varying oil temperatures or contamination levels. The RDFALBN features a cavity T-3A series 2 configuration with a capacity of up to 50 gpm (200 L/min) and operates at a maximum pressure of 5000 psi (350 bar). Its typical response time is around 2 milliseconds with a maximum leakage rate of 10 drops/minute upon reseat at 90% of the setting. Installation specifications include a valve hex size of 1-1/8 inches (28.6 mm) and an installation torque range of 45-50 lbf ft (61-68 Nm). The adjustment screw has an internal hex size of 5/32 inches (4 mm), while the locknut hex size is 9/16 inches (15 mm) with locknut torque ranging from 80-90 lbf in (9-10 Nm). Weighing approximately .50 lb (.25 kg), this valve incorporates Sun's floating style construction to prevent internal part binding due to excessive installation torque or machining variations in cavity/cartridge interfaces.
Direct-acting relief cartridges are normally closed, pressure-limiting valves used to protect hydraulic components from pressure transients. When the pressure at the inlet (port 1) reaches the valve setting, the valve starts to open to tank (port 2), throttling flow to limit the pressure rise. These valves are smooth and quiet, essentially zero leak, dirt tolerant, immune to silting and are very fast.
- All 2-port relief cartridges (except pilot reliefs) are physically and functionally interchangeable (same flow path, same cavity for a given frame size).
- Will accept maximum pressure at port 2; suitable for use in cross port relief circuits.
- The seals on the adjust screw are exposed to system pressure which means this valve can only be adjusted when the pressure is removed. The setting procedure is; check the setting, remove the pressure, adjust the valve, check the new setting.
- Valve is relatively insensitive to varying oil temperatures and oil borne contamination.
- Select a spring range where the desired relief setting is approximately mid-range to high between the minimum and maximum pressure to ensure maximum valve repeatability.
- Suitable for use in load holding applications.
- Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
- Cartridges configured with EPDM seals are for use in systems with phosphate ester fluids. Exposure to petroleum based fluids, greases and lubricants will damage the seals.
- 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-3A |
| Series | 2 |
| Capacity | 50 gpm200 L/min. |
| Factory Pressure Settings Established at | 4 gpm15 L/min. |
| Maximum Operating Pressure | 5000 psi350 bar |
| Response Time - Typical | 2 ms2 ms |
| Maximum Valve Leakage at Reseat | 10 drops/min.0,7 cc/min. |
| Reseat | >90% of setting>90% of setting |
| Adjustment - Number of Clockwise Turns to Increase Setting | 55 |
| Valve Hex Size | 1 1/8 in.28,6 mm |
| Valve Installation Torque | 45 - 50 lbf ft61 - 68 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 | .50 lb0,25 kg |
| Seal kit - Cartridge | Viton: 990-303-006 |
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Additional Resources
- Sun Offers Zinc-Nickel Plating for Corrosion Resistance
- Sun Cartridges with EPDM Seals
- Series 4 PLUS Cartridges Offer Higher Flows with Lower Pressure Losses
- Pilot-Operated, Balanced Poppet, Anti Shock Reliefs
- CavitySaver multi-function valves deliver single-cartridge solutions
- 'Soft' Relief Eliminates Pressure Spikes
- Tri-Grip Handknob Now Offered From Sun as a Standard Control Option
- QuickDesign with SmartConnect Offers Drag-and-Drop Schematic Tool
- Sun Introduces 'Hybrid' Valves
- CE/TÜV Certified Pressure Relief Valves
- Pressure Relief and Regulating Cartridge Valve Technical Tips
- Pilot Operated, Balanced Poppet Relief Valves
- Sun Expands Corrosion-Resistant Solutions
- Pressure Relief and Regulating Valves
- Manufacturing Sun Cartridge Cavities
- Performance Data
- Sun's Floating Style Screw-In Cartridge
- Units of Measure, Settings, and Conversions
- Cavity Information (S-171) and Tooling
- Sun Model Code Explanation; 999-901-334
- Cartridges: Materials of Construction
- Fluid and Temperature Recommendations
Notes:
- U.S. Patent #4,742,846; European Patent Pending
