SUN HYDRAULICS
RDFACSV

***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 RDFACSV (RDFACSV) is a direct-acting relief cartridge valve designed to provide pressure-limiting protection for hydraulic systems. This normally closed valve opens to tank port 2 when the inlet port 1 pressure reaches the set value, effectively throttling flow to control pressure spikes. Known for its smooth, quiet operation and essentially zero leakage, this valve is dirt-tolerant, immune to silting, and offers rapid response times. The RDFACSV model features interchangeable physical and functional characteristics across all 2-port relief cartridges of the same frame size, making it suitable for cross-port relief circuits. It can handle maximum pressure at port 2 and is ideal for load-holding applications due to its insensitivity to varying oil temperatures and contamination. The adjustment process requires depressurization before modifying settings, with a recommended spring range selection ensuring optimal repeatability. Notably, back pressure on tank port 2 adds directly to the valve setting at a 1:1 ratio. Cartridges equipped with EPDM seals are compatible with phosphate ester fluid systems but must avoid petroleum-based substances to prevent seal damage. The Sun floating style construction minimizes internal component binding risks due to excessive torque or machining variations. With a capacity of 50 gpm (200 L/min) and maximum operating pressure of 5000 psi (350 bar), this valve exhibits typical response times of approximately 2 ms and a reseat characteristic at 90% of the setting. Installation specifications include a valve hex size of 1-1/8 inches (28.6 mm) and an installation torque between 45-50 lbf-ft (61-68 Nm). The RDFACSV model weighs approximately .50 lb (.25 kg) and uses Viton seal kits identified by part number 990303006.