SUN HYDRAULICS
RPKSLBN

***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 RPKSLBN (RPKSLBN) is a pilot-operated, balanced poppet relief cartridge designed to function as a normally closed pressure regulating valve. It operates by opening to tank port 2 once the inlet port 1 pressure reaches the valve setting, effectively throttling flow to maintain regulated pressure. This valve is noted for its accuracy, smooth operation, quietness, rapid response time of approximately 7 ms, and minimal pressure rise relative to flow. It boasts immunity to cavitation issues such as noise and manifold erosion due to its internal modulating design. The valve supports a maximum operating pressure of 5000 psi (350 bar) and can accept maximum pressure at port 2, making it suitable for cross-port relief circuits. Its performance remains stable despite variations in oil temperature and contamination levels, thanks in part to a main stage orifice protected by a 150-micron stainless steel screen. Backpressure on tank port 2 directly adds to the valve setting at a 1:1 ratio. Users can specify W and Y controls with or without special settings; without special settings, the valve is adjustable across its full range using these controls. Corrosion-resistant options are available with external stainless steel or zinc-nickel plated components identified by model code suffixes AP or LH respectively. The cartridge incorporates Sun's floating style construction, reducing binding risks from installation torque or cavity machining variations. With a cavity size of T-18A Series 4 and a capacity of up to 200 gpm (760 L/min), this robust valve offers reliable performance with low leakage rates of up to ten drops per minute at reseat conditions. The RPKSLBN model features an adjustment screw internal hex size of 5/32 inches (4 mm) and requires specific installation torques for optimal operation.