SUN HYDRAULICS
PRFRLSN

$133.73 USD

SUN HYDRAULICS
Material:PRFRLSN
Model:PRFR-LSN
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 PRFRLSN (PRFRLSN) is a direct-acting pressure reducing valve designed to maintain a constant reduced pressure at port 1 from a higher primary pressure at inlet port 2. This valve features a damped construction for stable operation, allowing the use of high reduced pressure levels. Notably, it does not have relieving capabilities and should not be used in deadheaded applications, as low leakage on the reduced pressure side can lead to significant pressure increases. The PRFRLSN valve is an effective substitute for LPC valves when a higher pressure drop across an orifice is required, functioning as a normally open, restrictive compensating element. It is compatible with phosphate ester fluids when equipped with EPDM seals; however, exposure to petroleum-based fluids will damage these seals. The valve supports full reverse flow from port 1 to port 2 but may require an additional check valve if reverse free flow is necessary in the circuit. It operates optimally with inlet pressures up to 5000 psi and demonstrates superior dynamic response compared to pilot-operated models due to its direct operation design. The PRFRLSN is particularly suitable for accumulator circuits as it reduces secondary circuit leakage by eliminating pilot control flow. Pressure at port 3 directly affects the valve setting at a 1:1 ratio and should not exceed 5000 psi. The leakage rate specified in technical data occurs out of port 3 under specific conditions and varies based on pressure differential and fluid viscosity. The valve incorporates Sun's floating style construction to minimize internal part binding due to installation torque or machining variations. Key specifications include a maximum operating pressure of 5000 psi, maximum valve leakage of 50 cc/min at specified conditions, and adjustment capabilities through internal hex screws and locknuts with defined torque settings.

Description

Direct-acting, pressure reducing valves reduce a high primary pressure at the inlet (port 2) to a constant reduced pressure at port 1. These valves incorporate a damped construction for stable operation allowing the use of high reduced pressure.

Note: This valve has no relieving capability. It should not be used in a dead-headed application. If the reduced pressure side of the circuit has very low leakage the pressure may rise significantly. The pressure rise will vary from valve to valve.
This type of valve, PR*R, is a good replacement for an LP*C as a normally open, restrictive compensating element if a higher pressure drop across an orifice is needed.
Cartridges configured with EPDM seals are for use in systems with phosphate ester fluids. Exposure to petroleum based fluids, greases and lubricants will damage the seals.
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.
All spring ranges are tested for correct operation with 5000 psi (350 bar) inlet pressure.
Suitable for accumulator circuits since the absence of pilot control flow results in reduced secondary circuit leakage.
Direct operated version offers superior dynamic response compared to equivalent pilot operated models.
Pressure at port 3 is directly additive to the valve setting at a 1:1 ratio and should not exceed 5000 psi (350 bar).
Leakage specified in Technical Data is out of port 3 with a supply pressure of 2000 psi (140 bar) and the valve set at mid range. This leakage is directly proportional to pressure differential and inversely proportional to viscosity expressed in centistokes.
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	2 in³/min.30 cc/min.
Maximum Operating Pressure	5000 psi350 bar
Maximum Valve Leakage at 110 SUS (24 cSt)	3 in³/min.50 cc/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	Viton: 990-202-006

Show FAQ

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.
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.

SUN HYDRAULICSPRFRLSN

Additional Resources

SUN HYDRAULICS
PRFRLSN