SUN HYDRAULICS
SQJBKDN

***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 SQJBKDN (SQJBKDN) is a kickdown sequence valve designed to open completely and maintain an unrestricted flow path from port 1 to port 2 once the inlet pressure at port 1 surpasses the valve's preset threshold. This valve is ideal for applications where flow must continue uninterrupted as long as the pressure at port 1 remains higher than at port 2. To reset, the pressure at port 1 must drop below the setpoint, flow from port 1 to port 2 must stop, and pressure at port 2 should be equal to or greater than that at port 1. Notably, this valve is not suitable for load-holding applications and should be mounted on the actuator side of a system since flow cessation through the valve is necessary for resetting. The main stage orifice features a protective stainless steel screen of 150 microns. The pressure at drain port 3 directly adds to the valve setting in a one-to-one ratio, with a maximum allowable pressure of 5000 psi (350 bar). This model uses Sun's floating style construction to reduce internal part binding due to excessive installation torque or cavity machining variations. It fits into Cavity T-19A and belongs to Series 4 with a capacity of up to 120 gpm (480 L/min). Factory settings are established at the kickdown point with a maximum operating pressure of up to 5000 psi (350 bar) and typical response time around 25 ms. Installation requires specific torque values: valve hex size is approximately 1-5/8 inches (41.3 mm) with an installation torque range of 350-375 lbf.ft (474-508 Nm). The adjustment screw has an internal hex size of approximately 5/32 inches (4 mm), while the locknut hex size is about 9/16 inches (15 mm), requiring a torque setting between 80-90 lbf.in (9-10 Nm). The model weighs approximately 3.10 lb (1.40 kg) and includes a Viton seal kit option under part number: 990019006.