Flow control valve
Serie SRR..
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Reference: 100-P-000090-EN-20
Issue: 07.2025
S robust, simple and reliable
S easy coil change without opening the hydraulic
envelope
S flow rates are unaffected by temperature change or
when the higher load pressure alternates between the
outlet ports
S easy to service
S Dependable
S ZnNi coating (>
480h NSST)
1 Description
1.1 Generals
The flow control valves of the SRR series are used to set the
working speed of hydraulics actuators, the setting being
load-independent, and pressure compensated. The flow
rate is set by an adjustable slit-type orifice.
When used as a 3-way valve, the higher pressure can be
either at the A or the B port. The special orifice design en
sures that the flow setting is largely independent of the vis
cosity of the operating fluid. For a 2-way flow control func
tion please ask Bucher Hydraulics.
Developed specifically for use in load-sensing systems, the
valve options /01, /07, /15 and /16 extend the capabilities of
series SRR flow-control valves. Internal connections allow
the actual surplus-flow port (R) to be used for picking up
the LS signal or for unloading the LS system. These variants
enable system designers to create simple, compact and
flexible LS applications. As standard, the flow control valves
are supplied with proportional solenoids. Options /07 and
/16 are controlled by an ON/OFF solenoid.
The pressure relief valve acts on the spring chamber for the
pressure compensator. It is set by the manufacturer at the
factory according to the customer's requirements and fitted
with a safety cap.
With this version, surplus-flow must be routed to the tank.
1.2 Application examples
S Harvesters
S Sweepers
S Refuse collection vehicles
S Fertiliser spreaders
S Trailered machines
S Mowers
S Road rollers
S Municipal vehicles
S Forestry machines
S Wood chippers
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2 Symbols
2.1 2-way flow control valves
2.1.1 Type of operation: Solenoid and emergency pin (S)
SRRB…S2…
SRRB…S2…/01
SRRB…S2…/15
SRRB…S2…/16
SRRB…S2…/07
2.1.2 Type of operation: Solenoid and basic manual override (N)/
solenoid and deluxe manual override (T)
SRRB…
N
/
T
2…
SRRB…
N
/
T
2…/01
SRRB…
N
/
T
2…/15
SRRB…
N
/
T
2…/16
SRRB…T2…/07
SRRB…T2…/16
2.1.3 Type of operation: Manual override (H)
SRRB…H2…
SRRB…H2…-R
1)
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2.2 3-way flow control valves
2.2.1 Type of operation: Solenoid and emergency pin (S)
SRRB…S3…
SRRB…S3…-P
SRRB…S3…-R
1)
SRRB…S3…-RP
1)
SRRB…S3…/07
R
T(R)
T(R)
2.2.2 Type of operation: Solenoid and basic manual override (N)/
solenoid and deluxe manual override (T)
SRRB…
N
/
T
3…
SRRB…
N
/
T
3…-R
SRRB…
N
/
T
3…-P
SRRB…
N
/
T
3…-RP
1)
SRRB…T3…/07
2.2.3 Type of operation: Manual override (H)
SRRB…H3…
SRRB…H3…-R
1)
SRRB…H3…-P SRRB…H3…-RP
1)
1) Can only be used as a anti - cavitation check valve after consultation with Bucher Hydraulics.
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3 Technical data
General characteristics Unit Description, value
Design line mounting
Flow direction P → A controlled
P → R surplus flow discharge
Seals Viton (FPM)
De-energized position orifice closed
Mounting attitude Unrestricted;
preferably with coil at bottom (auto. air bleed)
Electrical characteristics Unit Description, value
Design high pressure; wet armature
Supply voltage 12 or 24 from an electronic controller
Power consumption W 21 at 12 V coil and Imax. = 2,3 A
21 at 24 V coil et Imax. = 1,15 A
Dither frequency required Hz 100 (pay attention to Imax.)
Relative duty cycle 100% at Imax.
Protection class (with a properly-fitted plug) AMP Junior Timer IP65
Deutsch plug IP67
DIN EN 60529
Electrical connection AMP Junior Timer plug connector (2-pole)
Deutsch plug DT04-2P-EP04
Hydraulical characteristics Unit Description, value
Constant flow range l/min 10, 16, 25, 32, 40, 50, 63, 80
1)
Inlet flow l/min max. 100
1)
Operating pressure bar max. 315
2)
Leakage cm
3
/min max. 100 at 100 bar
1)
Minimum pressure difference (pressure com
pensator)
bar 7
Control accuracy (depending on the nominal flow):
Load-dependency when under pressure
Hysteresis when operated
max. ± 2.5%
3)
max. ± 3.5%
3)
Fluids mineral oil to DIN 51524
4)
Fluid temperature range °C -20 ... +80
Viscosity range mm
2
/s 10 ... 300
Max. admissible level of contamination of the
hydraulic fluid
ISO 4406 class 20/18/15
1) Values refer to an oil viscosity of 35 mm
2
/s (cSt).
2) For higher pressures consult Bucher Hydraulics
3) Values refer to the selected flow range.
4) for other fxluids, consult Bucher Hydraulics.
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4 Performance graphs
4.1 Q - I characteristics
I (mA]) à 12 V
Q (%)
100
75
50
25
0
850 1150 1500 2000
400 600 800 1000
+3,5%
-3,5%
Q
max
1
I (mA]) à 24 V
2
1 Fine control range
2 Q
A
- constant flow pressurised
4.2 Variation in flow
0 100 200
p (bar)
Q
A
(l/min)
Q
max
Q
50 150 250
2
3
3 Q
A
- surplus flow pressurised
4.3 Pressure drop during vented bypass P " R
14
12
10
8
6
4
2
40 60 80 100
Δp (bar)
Q
zu
(l/min)
020
0
5
4
6
4 Control valve throtting curve
5 Control - Δp - characteristic 7 bar
6 Pressure loss area (the actual pressure-loss
characteristic is dependent on the tank pres
sure at port R)
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6 Models
6.1 Manual overrides
6.1.1 Emergency pin, SRR....S..
M
A
= max 6 Nm
M
A
= 13+2 Nm
max ∅2
1
approx. 200
13
1 emergency pin
IMPORTANT :By pressing the emergency pin
you operate the valve ON/OFF.
6.1.2 Basic manual override, SRR....N..
Q
0
to Q
max.
= approx. 3,5 turns at the rotary knob
27
M
A
= 8 Nm
approx. 200
S=3mm (1,5mm/U)
6.1.3 Basic manual override, SRR....T..
Q
0
to Q
max.
= approx. one turn at the rotary knob
approx. 212
30
M
A
= 8 Nm
6.2 Plug bases
AMP Junior Timer
J
Deutsch plug DT04-2P-EP04
T
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7 Ordering code
Flow control valve
Pipe mounting
Size
Constant flow range (10, 16, 25, 32, 40, 50, 63, 80 l/min)
e.g. 0...50 l/min = 050
Type of operation: solenoid + emergency pin = S
solenoid + basic manual override = N
solenoid + deluxe manual override = T
manual override = H
3-way = 3
2-way
(for this function please ask Bucher Hydraulics) = 2
Port threads
Standard: P: G¾” / A+R: G½” = G
(Adapters for pressure port P can be ordered separately, see section 9)
Design number (to be inserted by the factory)
Plug connector: AMP Junior Timer = J
Deutsch plug = T
Proportional solenoid supply voltage: DC 12 Volt = 12
DC 24 Volt = 24
Bypass check valve A → P= R
1)
without = *
Pressure relief function (surplus flow cannot be pressurised) = P
2)
3)
without = *
Options (see section 7.1)
212-
R
S
05RS
B3T-
0
G R P / P=
1) Can only be used as a anti - cavitation check valve after consultation with Bucher Hydraulics.
2) Not for use with the 2-way flow control valve.
3) Specify the pressure setting in plain text. Pressure setting by steps of 10 bar, between 50 and 310 bar.
7.1 Options
01 = Control flow relief when orifice closed (bypass nozzle, diameter 0.5, between A -> R (B)).
07 = 2 and 3-way flow control valve with ON/OFF solenoid.
15 = LS-port and proportional solenoid.
16 = LS-port and ON/OFF solenoid.
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8 Installation information
IMPORTANT!
When mounting the valve, ensure that the body is not subjected to any distorting forces. If necessary use shims to equalise
the level of the mounting points. Do not use any pipe fittings with tapered-threads!
To ensure reliable operation, G3/4” fittings with threaded stud ends, length of stud end 16 mm must be used as
port P. If required, adapters for G¾” to G½” can be supplied (see section 9).
Bleed all air from the system (if possible, operate the flow control valve several times at no-load)
9 Accessories
9.1 Adapter
G3/4”
G1/2”
G1/2”
1
G1/2"
M
A
= 180
+10
Nm
1 Adapter G3/4” -> G1/2”
Model Description Part number
Adapter G¾” -> G½” Adapter with sealing ring
profiled sealing ring to DIN 3869 is included with
delivery
100235660
E 2025 by Bucher Hydraulics GmbH, D-79771 Klettgau
www.bucherhydraulics.co
m
info.kl@bucherhydraulics.com
All rights reserved.
Data is provided for the purpose of product description only, and must not be construed as warranted characteristics in the legal sense. The
information does not relieve users from the duty of conducting their own evaluations and tests. Because the products are subject to continual
improvement, we reserve the right to amend the product specifications contained in this catalogue.
Classification: 430.310.335.310.
