SUN HYDRAULICS
RBACKWN

***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 RBACKWN (Material Number: RBACKWN) is a direct-acting, pilot relief cartridge designed to remotely control the pressure setting of other pilot-operated valves. This cartridge valve is suitable for load holding applications and should be used in conjunction with other higher flow valves due to its limited capacity to pilot flow. It features EPDM seals, making it compatible with systems using phosphate ester fluids, while exposure to petroleum-based fluids can damage these seals. The main stage orifice is safeguarded by a 150-micron stainless steel screen. Notably, back pressure on the tank port (port 2) directly adds to the valve setting at a 1:1 ratio. The RBACKWN model incorporates Sun's floating style construction, which minimizes the risk of internal parts binding due to excessive installation torque or cavity/cartridge machining variations. The valve supports adjustments throughout its full range using W or Y controls unless a special setting is specified, which then represents the maximum setting of the valve. This model is corrosion-resistant and can be identified by suffixes AP for external stainless steel components or LH for external zinc-nickel plated components. With a cavity size of T-10A and Series 1 capacity of 0.25 gpm (1 L/min), this cartridge operates at a maximum pressure of 5000 psi (350 bar). It boasts a typical response time of 2 ms and has a maximum valve leakage rate at 110 SUS (24 cSt) of five drops per minute (0.3 cc/min). The valve requires an installation torque between 30 - 35 lbf ft (41 - 47 Nm), with an adjustment screw internal hex size of 5/32 in. (4 mm) and locknut hex size of 9/16 in. (15 mm). The model weighs approximately .30 lb (.15 kg).