SUN HYDRAULICS
RPCCKWE

***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 RPCCKWE (RPCCKWE) is a pilot-operated, balanced-piston relief cartridge designed for precise pressure regulation in hydraulic systems. This valve remains normally closed, opening to the tank port 2 once the inlet port 1 pressure reaches the designated setting, thereby throttling flow to maintain consistent pressure levels. Known for its accuracy and smooth operation, the RPCCKWE offers a low-pressure rise relative to flow and operates quietly with moderate speed. It features interchangeability across all 2-port relief cartridges except pilot reliefs, sharing the same flow path and cavity for uniform frame sizes. The valve can handle maximum pressure at port 2, making it suitable for cross-port relief circuits; however, users should consider potential spool leakage in such applications. The minimum setting across all spring ranges is 75 psi (5 bar), but it is not recommended for load-holding applications due to possible spool leakage. Any back pressure on tank port 2 adds directly to the valve setting at a 1:1 ratio. The main stage orifice is safeguarded against contamination, ensuring reliable performance. For systems utilizing phosphate ester fluids, cartridges with EPDM seals are available; exposure to petroleum-based substances will harm these seals. This model incorporates Sun's floating style construction to reduce internal binding risks from excessive installation torque or machining variations. It has a capacity of up to 12 gpm (45 L/min) with a maximum operating pressure of 5000 psi (350 bar) and typically responds within 10 ms. The valve allows adjustment through five clockwise turns and features an installation torque range of 20-25 lbf ft (27-33 Nm). It weighs approximately .20 lb (.10 kg), and Viton seal kits are available under part number 990162006.