Created on 06/11/2015
c
2015 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
RDJA
Direct-acting relief valve
SERIES 4 / CAPACITY: 760 L/min. / CAVITY: T-18A
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
Adjustment - Number of Clockwise Turns to Increase Setting 5
Locknut Hex Size 15 mm
Locknut Torque 9 - 10 Nm
Seal kit - Cartridge Buna: 990-318-007
Seal kit - Cartridge Viton: 990-318-006
(L)CONTROL
L Standard Screw Adjustment
C Tamper Resistant - Factory Set
Q Capped and Lockwired
(A)ADJUSTMENT RANGE
A 500 - 3000 psi (35 - 210 bar), 1000 psi
(70 bar) Standard Setting
W 800 - 4500 psi (55 - 315 bar), 1000 psi
(70 bar) Standard Setting
B 300 - 1500 psi (20 - 105 bar), 1000 psi
(70 bar) Standard Setting
C 1000 - 6000 psi (70 - 420 bar), 1000 psi
(70 bar) Standard Setting
D 200 - 800 psi (14 - 55 bar), 400 psi (28
bar) Standard Setting
E 100 - 400 psi (7 - 28 bar), 200 psi (14
bar) Standard Setting
S 50 - 200 psi (3,5 - 14 bar), 100 psi (7 bar)
Standard Setting
(N)SEAL MATERIAL
N Buna-N
E EPDM
V Viton
MATERIAL/COATING
Standard Material/Coating
/AP Stainless Steel, Passivated
/LH Mild Steel, Zinc-Nickel
snhy.com/
RDJA
TECHNICAL FEATURES
U.S. Patent #4,742,846; European Patent Pending
NOTES
Model Code Example: RDJALANCONFIGURATION OPTIONS
Created on 06/11/2015
c
2015 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2
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.
The seals on the adjust screw are exposed to system pressure which means this valve can only be adjusted when the pressure is removed. The setting procedure
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.
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
RELATED ACCESSORIES
XRJB Hydrostatic transmission flushing assembly with cross-port relief
