SUN HYDRAULICS
RPIEKAN

***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 RPIEKAN (RPIEKAN) is a fast-acting, pilot-operated, balanced piston relief cartridge designed to safeguard hydraulic components from pressure transients. These normally closed, pressure-limiting valves open swiftly but sacrifice smoothness for speed. When the inlet port 1 pressure reaches the set threshold, the valve begins to open to tank port 2, throttling flow to mitigate pressure rise. Notably, these cartridges exhibit low pressure rise versus flow and respond very quickly with a typical response time of 2 milliseconds. They are interchangeable with all other 2-port relief cartridges except pilot reliefs within the same frame size, sharing identical flow paths and cavities. The valve can withstand maximum pressure at port 2 and is suitable for cross-port relief circuits; however, spool leakage should be considered in such applications. The main stage orifice is protected by a 150-micron stainless steel screen. Due to spool leakage, these valves are not recommended for load-holding applications. Back pressure on tank port 2 adds directly to the valve setting in a 1:1 ratio. The Sun floating style construction minimizes internal part binding due to excessive installation torque or cavity/cartridge machining variations. Key specifications include a capacity of up to 100 gpm (380 L/min), maximum operating pressure of 5000 psi (350 bar), and factory pressure settings established at 4 gpm (15 L/min). The maximum valve leakage at 110 SUS (24 cSt) is specified as 4 in\u00b3/min (65 cc/min) at 1000 psi (70 bar). The cartridge features an adjustable setting with five clockwise turns required for adjustment and includes Viton seals under seal kit number 990016006. Installation torque ranges from 150-160 lbf ft (203-217 Nm), with adjustment screw and locknut hex sizes being ^5/32 inch (4 mm) and ^9/16 inch (15 mm), respectively.