SUN HYDRAULICS
RDBALDV

***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 RDBALDV (RDBALDV) is a direct-acting relief cartridge designed to protect hydraulic components from pressure transients. Normally closed, this pressure-limiting valve opens at the inlet port 1 when the pressure reaches the set threshold, allowing flow to tank port 2 to limit pressure rise. Known for its smooth and quiet operation, it features zero leak capability, dirt tolerance, and immunity to silting. The valve is fast in response and can handle a maximum operating pressure of up to 5000 psi (350 bar). It is interchangeable with all 2-port relief cartridges except pilot reliefs, sharing the same flow path and cavity for a given frame size. The RDBALDV is suitable for cross-port relief circuits and load holding applications due to its ability to accept maximum pressure at port 2. The valve's setting procedure involves removing system pressure before adjustment since the seals on the adjust screw are exposed to system pressure. It remains relatively insensitive to varying oil temperatures and contamination, ensuring reliable performance across different conditions. For optimal repeatability, select a spring range where the desired relief setting falls between midrange and high of its minimum and maximum capabilities. Back pressure on tank port 2 directly adds to the valve setting at a 1:1 ratio. This model incorporates Sun's floating style construction that minimizes internal parts binding due to excessive installation torque or cavity/cartridge machining variations. The cartridge features an installation torque of 20-25 lbf ft (27-33 Nm), with an internal hex size adjustment screw of 5/32 inches (4 mm) and locknut torque of 80-90 lbf in (9-10 Nm). With a flow capacity of up to 12 gpm (45 L/min), it offers reliable performance in various hydraulic systems requiring precise pressure control.