SUN HYDRAULICS
PBFFLQN

$104.34 USD

SUN HYDRAULICS
Material:PBFFLQN
Model:PBFF-LQN
Summary:Cartridge

Quantity in stock: 0

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***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 PBFFLQN (PBFFLQN) is a pilot-operated, pressure reducing valve designed to efficiently manage hydraulic systems with varying pressure requirements using a single pump. This valve reduces high primary pressure at inlet port 2 to a consistent reduced pressure at port 1, making it versatile for circuits needing multiple pressure levels. The PBFFLQN features a main stage orifice drilled into the piston, enhancing its durability in demanding applications. It is interchangeable with other three-port pressure reducing and reducing-relieving cartridges of the same frame size and flow path, which simplifies installation and maintenance. For optimal performance, the full capacity return line port 3 should be utilized when configuring mounting setups with reducing-relieving cartridges. If reverse flow from reduced pressure port 1 to inlet port 2 is necessary, it is advisable to incorporate an additional check valve in the circuit to prevent the main spool from closing. The valve's pilot flow consumption can be minimized by opting for direct-acting reducing-relieving valves if critical. The recommended maximum inlet pressures vary based on adjustment ranges: D, E, N, and Q are tested up to a 2000 psi maximum differential; A, B, and H up to 3000 psi; while C and W withstand up to 5000 psi. This pilot-operated valve exhibits stable performance with low hysteresis and flat pressure-flow characteristics. However, for applications requiring rapid dynamic response, direct-acting valves are preferred due to their faster operation. The PBFFLQN incorporates Sun's floating style construction which reduces the risk of internal parts binding during installation or due to machining variations. It has a capacity of 20 gpm (80 L/min) and weighs approximately 0.60 lb (0.30 kg). The design includes specific torque specifications for installation and adjustment components ensuring proper setup and reliable operation.

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.

These valves have the main stage orifice drilled into the piston rather than a staked-in orifice. This allows the valve to survive physically demanding applications.
All three-port pressure reducing and reducing/relieving cartridges are physically interchangeable (i.e. same flow path, same cavity for a given frame size). When considering mounting configurations, it is sometimes recommended that a full capacity return line (port 3) be used with reducing/relieving cartridges.
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.
If pilot flow consumption is critical, consider using direct acting reducing/relieving valves.
Recommended maximum inlet pressure is determined by the adjustment range. Ranges D, E, N, and Q are tested with a 2000 psi (140 bar) maximum differential between inlet and reduced pressure. Ranges A, B, and H are tested with a 3000 psi (210 bar) maximum differential between inlet and reduced pressure. Ranges C and W are tested with 5000 psi (350 bar) of inlet pressure.
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).
Pilot operated reducing, reducing/relieving valves by nature are not fast acting valves. For superior dynamic response, consider direct acting valves.
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-2A
Series	2
Capacity	20 gpm80 L/min.
Factory Pressure Settings Established at	blocked control port (dead headed)blocked control port (dead headed)
Control Pilot Flow	10 - 15 in³/min.0,16 - 0,25 L/min.
Adjustment - Number of Clockwise Turns to Increase Setting	55
Valve Hex Size	1 1/8 in.28,6 mm
Valve Installation Torque	45 - 50 lbf ft61 - 68 Nm
Adjustment Screw Internal Hex Size	5/32 in.4 mm
Locknut Hex Size	9/16 in.15 mm
Locknut Torque	80 - 90 lbf in.9 - 10 Nm
Model Weight	.60 lb0,30 kg
Seal kit - Cartridge	Polyurethane: 990-002-002

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.

Additional Resources

Notes:

For Series 1 cartridges configured with an O control (panel mount handknob), a .75 in. (19 mm) diameter hole is required in the panel.

SUN HYDRAULICSPBFFLQN

Additional Resources

SUN HYDRAULICS
PBFFLQN