SUN HYDRAULICS
RDJALDV

***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 RDJALDV (RDJALDV) is a direct-acting relief cartridge designed for hydraulic systems to protect components from pressure transients. This normally closed, pressure-limiting valve opens to the tank port when the inlet port reaches the set pressure, effectively throttling flow to control pressure rise. Known for being smooth, quiet, and essentially zero-leak, it is dirt-tolerant and immune to silting, offering rapid response times. Physically and functionally interchangeable with other 2-port relief cartridges of the same frame size, it can handle maximum pressure at port 2 and is suitable for cross-port relief circuits. The valve's adjust screw seals are exposed to system pressure; thus, adjustments can only be made when system pressure is removed. It is relatively insensitive to oil temperature variations and contamination, ensuring repeatability when selecting a spring range where the desired setting falls midrange to high between minimum and maximum pressures. It is also adept for load-holding applications as back pressure on the tank port directly adds to the valve setting at a 1:1 ratio. Cartridges with EPDM seals are intended for systems using phosphate ester fluids; exposure to petroleum-based fluids can damage these seals. The valve features Sun's floating style construction to minimize internal binding due to excessive torque or machining variations. It has a cavity T-18A series 4 capacity of 200 gpm (760 L/min), maximum operating pressure of 5000 psi (350 bar), typical response time of 2 ms, and reseat at 90% of setting with minimal leakage upon reseat. The adjustment requires five clockwise turns for increased settings with specific torque requirements for installation and locknut adjustments. The model weighs approximately 3.30 lb (1.50 kg) and uses Viton seal kits like 990318006 for maintenance or replacement needs.