SUN HYDRAULICS
RDBALSV

***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 RDBALSV (RDBALSV) is a direct-acting relief cartridge designed to protect hydraulic components from pressure transients. This normally closed, pressure-limiting valve operates by opening to tank port 2 when the inlet port 1 pressure reaches the valve setting, effectively throttling flow to prevent excessive pressure rise. Notable for its smooth, quiet operation and essentially zero leakage, this valve is dirt tolerant, immune to silting, and offers rapid response times. It is interchangeable with all other 2-port relief cartridges of the same size and flow path. The RDBALSV can handle maximum pressure at port 2, making it suitable for cross port relief circuits and load holding applications. This valve features an adjustment screw with seals exposed to system pressure; thus, adjustments must be made with the system depressurized. For optimal performance, select a spring range where the desired relief setting falls within the mid-to-high range of its capacity. The valve's design ensures it remains relatively insensitive to variations in oil temperature and contamination. Additionally, back pressure on tank port 2 adds directly to the valve setting at a 1:1 ratio. The RDBALSV incorporates Sun's floating style construction to minimize internal binding due to installation torque or machining variations. It has a capacity of 12 gpm (45 L/min) and operates up to a maximum pressure of 5000 psi (350 bar). With typical response times around 2 milliseconds and minimal leakage at reseat (10 drops/min or 0.7 cc/min), this model ensures reliable performance under demanding conditions. Configurations with EPDM seals are available for systems using phosphate ester fluids but should not be exposed to petroleum-based substances. The valve weighs approximately .20 lb (0.10 kg) and includes detailed specifications for installation torque and adjustment procedures.