SUN HYDRAULICS
RED/REL VALVE
PBBBKQN

$84.60 USD

SUN HYDRAULICS
Material:PBBBKQN
Model:PBBB-KQN
Summary:Cartridge

Quantity in stock: 2

***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 PBBBKQN (PBBBKQN) is a pilot-operated pressure reducing valve designed to manage high primary pressures at the inlet port 2, reducing them to a constant pressure at port 1, which is ideal for circuits requiring varied pressure levels using a single pump. This valve supports full reverse flow from the reduced pressure port 1 to inlet port 2, although this may cause the main spool to close. To facilitate reverse free flow in a circuit, an additional check valve may be necessary. The minimum setting for this valve is 75 psi (5 bar) across all spring ranges. Known for its exceptionally flat pressure-flow characteristics, the PBBBKQN offers stability and low hysteresis, making it highly reliable in maintaining consistent performance. Pressure at port 3 can directly add to the valve setting on a 1:1 basis but should not exceed 5000 psi (350 bar). The design incorporates Sun's floating style construction to minimize internal part binding due to excessive installation torque or variations in cavity/cartridge machining. With a capacity of 5 gpm (20 L/min), this valve operates with maximum pressures up to 5000 psi (350 bar) and requires an adjustment of approximately five clockwise turns to increase settings. It features several adjustable components including an internal hex size adjustment screw and locknut with specified torque requirements. The model weighs approximately .30 lb (.15 kg) and uses Viton seals for enhanced durability. This pilot-operated valve is suitable for applications where precise pressure regulation is critical, providing moderate speed and easy adjustability while maintaining robust performance under various operational conditions.

Description

Pilot-operated, pressure reducing valves reduce a high primary pressure at the inlet (port 2) to a constant reduced pressure at port 1, allowing circuits with multiple pressure requirements to be operated using a single pump.

Full reverse flow from reduced pressure (port 1) to inlet (port 2) may cause the main spool to close. If reverse free flow is required in the circuit, consider adding a separate check valve to the circuit.
Minimum setting is 75 psi (5 bar) for all spring ranges.
Pilot operated valves exhibit exceptionally flat pressure/flow characteristics, are very stable and have low hysteresis.
Pressure at port 3 is directly additive to the valve setting at a 1:1 ratio and should not exceed 5000 psi (350 bar).
Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge machining variations.

Cavity	T-163A
Series	0
Capacity	5 gpm20 L/min.
Factory Pressure Settings Established at	blocked control port (dead headed)blocked control port (dead headed)
Maximum Operating Pressure	5000 psi350 bar
Control Pilot Flow	7 - 10 in³/min.0,11 - 0,16 L/min.
Adjustment - Number of Clockwise Turns to Increase Setting	55
Valve Hex Size	3/4 in.19,1 mm
Valve Installation Torque	20 - 25 lbf ft27 - 33 Nm
Adjustment Screw Internal Hex Size	5/32 in.4 mm
Locknut Hex Size	1/2 in.12,7 mm
Locknut Torque	80 - 90 lbf in.9 - 10 Nm
Model Weight	.30 lb0,15 kg
Seal kit - Cartridge	Viton: 990-163-006

Show FAQ

Direct acting or pilot operated - what do I use?	Direct-acting valves are used to prevent over pressure, and pilot-operated valves are used to regulate pressure. If you are unsure, use a direct-acting valve. Sun's direct acting valves are very fast, dirt tolerant, stable, and robust. Sun's pilot-operated valves are moderately fast, they have a low pressure rise vs. flow curve, and they are easy to adjust.
How big is a drop of hydraulic oil?	There are exactly 250 Sun drops in a cubic inch or 15 in a cc.
What are the tolerances on pressure settings for Sun's pressure control valves?	Pressure setting tolerances are listed in our Performance Data page. A link to this page can also be found in the Additional Resources tab of the applicable product page.
Can I back flow through a reducing valve from port 1 to port 2?	Yes. A reducing or reducing/relieving valve is normally open. If the pressure in the secondary circuit is less than the setting, it will be open.2 caveats: (1) If the valve is in the reducing mode and you suddenly reverse the flow, the valve will not have time to open and will shift into relieving mode or (2) If the back flow generates a pressure drop through the valve that exceeds the setting, the valve will shift into the relieving mode.When in doubt, use a reverse flow check.
I need a reducer on B. Can I connect the drain to A?	Yes. If you look in the sandwich section you will see that we offer many such packages. When you are pressurizing B, A is connected to tank, allowing the reducer to do its job. When you reverse, the drain or tank port of the reducer is pressurized by A. This increases the setting of the reducer and helps keep the reducer open in the reverse flow direction.
What do you mean by maximum differential?	Our reducing valves are outside-in valves; the supply pressure on the outside of the working parts is higher than the inside. At some pressure differential, the outside (sleeve) will close in on the piston and cause the valve to stick. A D range is adjustable from 25 to 800 psi with a maximum differential of 2000 psi. This means you could set the valve at 600 psi and expect it to work correctly with a supply pressure of 2600 psi. The valve may work at higher differentials, but we do not recommend it. The W and C ranges are tested over their entire range with an inlet pressure of 5000 psi. All direct-acting valves are tested with an inlet pressure of 5000 psi.

SUN HYDRAULICSRED/REL VALVEPBBBKQN

Additional Resources

SUN HYDRAULICS
RED/REL VALVE
PBBBKQN