SUN HYDRAULICS
RDBAKSV

***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 RDBAKSV (RDBAKSV) is a direct-acting relief cartridge designed to protect hydraulic components from pressure transients. This normally closed, pressure-limiting valve opens to the tank port when inlet pressure reaches the set threshold, effectively throttling flow to limit pressure rise. Known for its smooth and quiet operation, the RDBAKSV is essentially zero-leak and dirt-tolerant, making it immune to silting and very fast in response. It features physical and functional interchangeability with all 2-port relief cartridges, except pilot reliefs, ensuring a consistent flow path and cavity size for a given frame size. The valve can withstand maximum pressure at port 2, making it suitable for cross-port relief circuits and load-holding applications. The adjust screw seals are exposed to system pressure; thus, adjustments can only be made when the system is depressurized. The recommended procedure involves checking the setting, removing pressure, adjusting the valve, and rechecking the setting. The valve's performance remains stable across varying oil temperatures and contaminants. For optimal repeatability, it's advised to select a spring range where the desired relief setting falls mid-to-high between minimum and maximum pressures. This model allows back pressure on tank port 2 to directly add to the valve setting at a 1:1 ratio. Cartridges with EPDM seals are compatible with phosphate ester fluids but should avoid petroleum-based substances to prevent seal damage. The Sun floating style construction minimizes internal part binding risks due to excessive installation torque or cavity/cartridge machining variations. Specifications include a capacity of 12 gpm (45 L/min), maximum operating pressure of 5000 psi (350 bar), typical response time of 2 ms, and maximum leakage at reseat of 10 drops/min (0.7 cc/min). The adjustment requires five clockwise turns for increasing settings with specific torque requirements for installation components.