SUN HYDRAULICS
RPKSKNN

***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 RPKSKNN (RPKSKNN) is a pilot-operated, balanced-poppet relief cartridge designed to function as a pressure regulating valve. This normally closed valve begins to open when the inlet port 1 reaches the preset pressure, allowing flow to the tank port 2 to maintain regulated pressure. Notably accurate and smooth, these valves operate quietly and quickly with minimal pressure rise relative to flow. The internal modulating mechanism makes them resistant to cavitation-related issues such as noise and manifold erosion. Capable of handling maximum pressure at port 2, they are ideal for cross-port relief circuits and remain stable despite variations in oil temperature or contamination. The main stage orifice is safeguarded by a 150-micron stainless steel screen, and backpressure on tank port 2 directly influences the valve setting at a 1:1 ratio. Adjustable via W or Y controls, these valves can be specified with or without special settings for maximum adjustability. Corrosion-resistant versions are available with external components made of stainless steel (suffix AP) or zinc-nickel plated (suffix LH). The Sun floating style construction minimizes binding risks due to installation torque or machining variations. With a cavity size of T-18A Series 4 and a capacity of 200 gpm (760 L/min), this cartridge valve operates up to a maximum pressure of 5000 psi (350 bar), typically responding within 7 milliseconds. It features minimal leakage at reseat with only up to 10 drops/minute (0.7 cc/min). Installation requires a torque of 350-375 lbf ft (474-508 Nm), while adjustments need an internal hex size of 5/32 inches (4 mm). The model weighs approximately 2.50 lb (1.15 kg) and uses Viton seal kits for optimal performance in various applications, including scenarios requiring quick response relief mechanisms like portable grain augers for silos.