SUN HYDRAULICS
RPCCKNV

***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 RPCCKNV (RPCCKNV) is a pilot-operated, balanced-piston relief cartridge designed for precise pressure regulation in hydraulic systems. This normally closed valve opens to tank port 2 when the inlet pressure at port 1 reaches the valve's set point, allowing it to throttle flow and maintain consistent system pressure. Known for its accuracy and low-pressure rise versus flow characteristics, this valve operates smoothly and quietly with moderate response speed. It is physically and functionally interchangeable with other 2-port relief cartridges of the same frame size, facilitating easy integration into existing systems. This relief cartridge is suitable for cross-port relief circuits, accepting maximum pressure at port 2; however, users should consider spool leakage in such applications. The minimum setting for all spring ranges is 75 psi (5 bar), but it is not recommended for load-holding applications due to potential spool leakage. Back pressure on tank port 2 adds directly to the valve setting at a 1:1 ratio, which should be considered during system design. The RPCCKNV features a main stage orifice protected against contamination and incorporates Sun's floating style construction to minimize internal binding risks due to installation torque or machining variations. It supports a capacity of up to 12 gpm (45 L/min) and can operate at a maximum pressure of 5000 psi (350 bar). The typical response time is approximately 10 milliseconds with minimal valve leakage under specified conditions. For systems using phosphate ester fluids, cartridges configured with EPDM seals are available; however, exposure to petroleum-based fluids should be avoided as it can damage these seals. The valve includes specific installation and adjustment specifications such as hex sizes for adjustment screw and locknut, as well as torque requirements for secure installation.