SUN HYDRAULICS
RQCBCQN

***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 RQCBCQN (RQCBCQN) is a kickdown relief cartridge designed to function similarly to a circuit breaker in hydraulic systems. This valve activates by completely opening when the pressure at inlet port 1 surpasses the pre-set threshold, allowing unrestricted flow from port 1 to tank port 2. The valve remains open as long as the pressure at port 1 exceeds that at port 2, and it resets only when flow ceases and pressures equalize between ports. Key features include a main stage orifice shielded by a 150-micron stainless steel screen, and it\u2019s crucial to note that this valve is unsuitable for load-holding applications. It is primarily intended for use on the actuator side of hydraulic systems, where flow must stop for resetting, making it less effective on the pump side unless pump flow can be halted. The RQCBCQN model incorporates Sun's floating style construction to minimize internal component binding due to excessive torque or machining variations. It fits within cavity T-162A series 0 and has a capacity of up to 12 gpm (45 L/min). The maximum operating pressure reaches up to 5000 psi (350 bar), with typical response times around 25 ms. Valve leakage is minimal at specified conditions, with adjustment capabilities through clockwise turns of an internal hex screw. The valve's installation torque ranges from 20-25 lbf-ft (27-33 Nm), and it includes a locknut requiring specific torque settings. Back pressure on tank port 2 directly affects the valve setting on a one-to-one ratio basis. All two-port relief cartridges except pilot reliefs are interchangeable within their frame size, sharing similar flow paths and cavity dimensions. This cartridge is not recommended for system relief applications due to potential overlap preventing false tripping; however, using a direct-acting relief valve in conjunction could offer additional protection against overpressure scenarios.