Created on 11/03/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
RBFA
Bi-directional direct-acting relief valve
SERIES 2 / CAPACITY: 120 L/min. / CAVITY: T-3A
The bi-directional, direct-acting relief cartridge is a normally closed, pressure-limiting valve used to protect hydraulic
components from pressure transients. When the pressure differential between ports 1 and 2 exceeds the valve
setting, the valve starts to open, throttling flow to limit the pressure rise, regardless of the direction.
Both directions have very similar setting and performance.
TECHNICAL DATA
Cavity T-3A
Series 2
Capacity 120 L/min.
Factory Pressure Settings Established at 15 L/min.
Maximum Operating Pressure 350 bar
Response Time - Typical 2 ms
Maximum Valve Leakage at Reseat 30 drops/min.
Reseat >85% of setting
Hysteresis ≤ 3 %
Adjustment - Number of Clockwise Turns to Increase Setting 5
Valve Hex Size 28,6 mm
Valve Installation Torque 61 - 68 Nm
Seal kit - Cartridge Buna: 990303007
Seal kit - Cartridge Polyurethane: 990303002
Seal kit - Cartridge Viton: 990303006
Model Weight 0.31 kg.
(L)CONTROL
L Standard Screw Adjustment
C Tamper Resistant - Factory Set
(W)ADJUSTMENT RANGE
W 800 - 4500 psi (55 - 315 bar), 1000 psi
(70 bar) Standard Setting
C 1500 - 6000 psi (105 - 420 bar), 1500
psi (105 bar) Standard Setting
(N)SEAL MATERIAL
N Buna-N
E EPDM
V Viton
snhy.com/
RBFA
TECHNICAL FEATURES
Because the modulating occurs inside the cartridge, these valves are immune to most of the problems associated with cavitation, namely noise and manifold
erosion.
The seals on the adjust screw are exposed to pressure at port 1 which means this valve can only be adjusted when the pressure is removed or port 2 is used to set
Model Code Example: RBFALWNCONFIGURATION OPTIONS
Created on 11/03/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2
the valve. The setting procedure at port 1 is; check the setting, remove the pressure, adjust the valve, check the new setting.
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.
All 2-port relief cartridges (except pilot reliefs) are physically and functionally interchangeable (same flow path, same cavity for a given frame size).
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
