SUN HYDRAULICS
RDFALCN

***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 RDFALCN (RDFALCN) is a direct-acting relief cartridge designed to protect hydraulic components from pressure transients by functioning as a normally closed, pressure-limiting valve. Upon reaching the designated pressure at the inlet port, the valve opens to the tank port, effectively throttling flow to limit pressure rise. This ensures smooth and quiet operation with essentially zero leakage, making it dirt tolerant and immune to silting. Notably fast in response, this valve is suitable for cross-port relief circuits and load-holding applications due to its capacity to accept maximum pressure at port 2. The RDFALCN is interchangeable with other 2-port relief cartridges of the same frame size, offering consistent functionality and flow paths. It features a robust construction that minimizes internal binding from excessive installation torque or machining variations. The valve's adjustment requires system pressure removal due to seals on the adjust screw being exposed to system pressure; adjustments are made by checking settings, removing pressure, adjusting the valve, and rechecking settings. This model is relatively insensitive to oil temperature fluctuations and contamination, enhancing its reliability in various conditions. The RDFALCN supports systems using phosphate ester fluids when equipped with EPDM seals but should avoid petroleum-based fluids as they can damage these seals. For optimal performance, select a spring range where desired relief settings are mid-to-high between minimum and maximum pressures. Key specifications include a capacity of 50 gpm (200 L/min), maximum operating pressure of 5000 psi (350 bar), typical response time of 2 ms, and reseat at 90% of setting. Installation requires specific torques for both valve installation (45-50 lbf ft) and locknut (80-90 lbf in). The model weighs .50 lb (.25 kg) and uses Viton seal kits for maintenance.