SUD6A-V4/I
1-5/16-12 UNF • Q
max
200 l/min (53 GPM) • p
max
350 bar (5100 PSI)
1
2
3
4
Symbol
2
4
1
3
(1450)
(2176)
(725)
(4351)
(5076)
(2901)
(3626)
100
50
250
350
150
200
300
0 1 2 3 4 5
Subject to change · SUD6A-V4/I_5225_2en_05/2017
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Page 1
Unloading Valve, External Drain, Spool Type, Pilot Operated
Technical Features
Functional Description
Technical Data
Characteristics measured at ν = 32 mm
2
/s (156 SUS)
Input pressure acts on port 1 of the valve and system pressure operates on the pilot port 4. When the pressure
at port 1 rises to the valve setting, the relief section opens and the system pressure acts on the pilot piston
to hold the valve in the open position. The ratio between the pilot piston diameter and the seat diameter
of the relief valve pilot section ensures that the valve remains in the fully open position until the system
pressure drops to approximately 85 % of the unload pressure. The valve has a drain port (3) which allows
unused by-pass oil to be used for a secondary circuit.
Valve size / Cartridge cavity 1-5/16-12 UNF-2A / V4
Max. flow l/min (GPM) 200 (52.8)
Max. operating pressure bar (PSI) 350 (5080)
Differential unload/reload % 10 - 15
Fluid temperature range (NBR) °C (°F) -20... + 90 (-4 ... +194)
Max. leakage ml/min 35
Mass kg (Ibs) 0.74 (1.63)
Datasheet Type
General information GI_0060 Products and operating conditions
Cavity details SMT_0019 SMT-V4*
Spare parts SP_8010
Operating pressure p [bar (PSI)]
Time [s]
Typical valve performance
Pump unload to tank
› Accumulator charging valve / low pressure pump unloading valve to tank in double pump systems
› Excellent stability throughout flow range with rapid response to dynamic pressure changes
› Low hysteresis, accurate pressure control and low pressure drop
› Wide pressure range up to 350 bar
› Hardened precision parts
› Sharp-edged steel seats for dirt-tolerant performance
› Leak-free closing, suitable for fast cycling with long life
› Adjustable by allen key
› In the standard version, the valve is zinc-coated for 240 h protection acc. to ISO 9227
1-5/16-12 UNF-2A
17
1 1/2"
100+2 Nm
4
(74+1.5 lbf.ft)
81 (3.19) 49 (1.93) MAX
1
2
3
4
Subject to change · SUD6A-V4/I_5225_2en_05/2017
www.argo-hytos.com
Page 2
Dimensions in millimeters (inches)
Application Example
The valve is used to unload a pump to the tank when the pressure
in a separate part of the circuit reaches a pre-set value.
The valve closes when the pressure has dropped to approximately
85 % of the unload pressure, causing the circuit to reload.
The most common application is to maintain the pressure in an accumulator,
which may be used in an emergency to operate critical hydraulic functions.
Unloading valve, external drain,
spool type, pilot operated
1-5/16-12 UNF
Ordering Code
SUD6A-V4/I - -
20
35
A
Factory setting [bar @ l/min]
100 bar at 4.8 l/min
200 bar at 4.8 l/min
100/4,8
200/4,8
Surface treatment
zinc-coated (ZnCr-3), ISO 9227 (240 h)
Pressure range
30 - 210 bar (435 - 2900 PSI), standard setting 100 bar
50 - 350 bar (725 - 5080 PSI), standard setting 200 bar
No designation
Seals
NBR
