Created on 10/16/2015
c
2015 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
RDFA3
Non-adjustable direct-acting relief valve
SERIES 2 / CAPACITY: 200 L/min. / CAVITY: T-3A
Non-adjustable direct-acting relief cartridges are normally closed, pressure-limiting valves used to protect hydraulic
components from pressure transients. When the pressure at the inlet (port 1) reaches the valve setting, the valve
starts to open to tank (port 2), throttling flow to limit the pressure rise. These valves are smooth and quiet,
essentially zero leak, dirt tolerant, immune to silting and are very fast.
TECHNICAL DATA
Factory Pressure Settings Established at 15 L/min.
Maximum Operating Pressure 350 bar
Response Time - Typical 2 ms
Maximum Valve Leakage at Reseat 0,7 cc/min.
Reseat >90% of setting
Seal kit - Cartridge Buna: 990-303-007
Seal kit - Cartridge EPDM: 990-303-014
Seal kit - Cartridge Polyurethane: 990-303-002
Seal kit - Cartridge Viton: 990-303-006
(A)ADJUSTMENT RANGE
A 500 - 3000 psi (35 - 210 bar)
C 1000 - 6000 psi (70 - 420 bar)
D 200 - 800 psi (14 - 55 bar)
(N)SEAL MATERIAL
N Buna-N
V Viton
snhy.com/
RDFA3
TECHNICAL FEATURES
Customer must specfy setting. The valve will be factory set and is tamper proof.
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.
All 2-port relief cartridges (except pilot reliefs) are physically and functionally interchangeable (same flow path, same cavity for a given frame size).
Will accept maximum pressure at port 2; suitable for use in cross port relief circuits.
Valve is relatively insensitive to varying oil temperatures and oil borne contamination.
Select a spring range where the desired relief setting is approximately mid-range to high between the minimum and maximum pressure to ensure maximum valve
repeatability.
Suitable for use in load holding applications.
Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
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.
PERFORMANCE CURVES
Model Code Example: RDFA3ANCONFIGURATION OPTIONS
