X
-Series
X
Directional
Control Valve
D
X
-6
Key valve features
DX-6 is a sectional valve designed for
max. operating pressures up to 350 bar
and max. pump  ows up to 180 l/min with
“Q-inlet”. For standard inlets without  ow
regulator the recommended max. pump
ows is 140 l/min. The valve is available
with 1 to 10 working sections per valve
assembly.
DX-6 includes as standard a variety of
sections, spools, spool controls and
additional parts in a modular design.
That makes the valve very  exible.
The valve is, as standard, setup for both
manual and remote control. The manual
controlled sections can either be with
open spool ends or encapsulated. The
encapsulation decreases in a signi cant
way the risk for external leakage and
makes the valve well adapted for
applications in demanding environment.
The spool controls for remote control are
generally designed as complete modules
for assembling on one of the valve sides.
DX-6 is in  rst place designed as an open
center valve for  xed displacement pumps
but can also be con gured for variable
displacement pumps. It is available with
manual, hydraulic or electro-hydraulic
proportional remote control.
DX-6 can be fully adapted for marine
applications. The valve offers excellent
operating characteristics, and good
controllability on a wide range of machinery
due to the specially designed spools.
Low and uniform spool forces are the result
of careful balancing of the  ow forces.
Q-inlet
The Q-inlet is designed with a  ow control
(Q-function) that by-passes the major part
of the pump  ow to tank when the system
is idling, still giving access to full pump  ow
when the working sections are operated.
Besides greatly reducing heat generation
this also provides improved operating
characteristics.
Applications
The DX-6 is ideal for applications where
you need excellent control characteristics
such as cranes, sky-lifts, garbage
trucks, demountable bodies, excavators,
Technical data
Pressure and  ow values *
Max. operating pressure set per port:
P1, P2, PM: 350 bar (35.0 MPa)
A, B: 400 bar (40.0 MPa)
T1, T2, T3: 20 bar (2.0 MPa)
Pp: 30 bar (3.0 MPa)
Tp: 5 bar (0.5 MPa)
X, Y: 25 bar (2.5 MPa)
Max. permissible  ow either on port P1 or P2:
Inlet without  ow control function: 140 l/min
Inlet with  ow control function: 180 l/min
Further data
Spool stroke nominal: +/-7 mm
Spool control force spool control 9M1:
Neutral position: 90 N
Max. spool stroke: 105 N
Permissible contamination level:
Spool control M: Equal or better than 20/18/ 14 as per ISO 4406
Spool control H, EH: Equal or better than 20/ 17/ 13 as per ISO 4406
Viscosity range: 10 – 400 mm
2
/s (cSt)
Higher viscosity allowed at start up.
Leakage A, B → T at 100 bar, 32 cSt and 40 °C: ≤12 cc/min
Pressure  uid: Mineral oil and syntetic oil based on mineral oil
HL, HLP according to DIN 51524.
Fluid temperature range: -15 °C up to +80 °C
* Higher values are possible, depending on application. For applications with demands
that exceed stated data above, please contact us for consideration.
MTTFd value after consultation with HYDAC.
telescopic load handlers, skid-loaders,
wheel loaders etc.
Remote control
As remote controlled the valve offers
compact design with internal pilot oil supply,
solenoids in a compact assembly on one
side of the valve and integrated hand levers
for manual override / manual operation.
The integrated pilot supply system for the
electro-hydraulic remote control makes the
valve easy to install and gives a reliable
remote control function. It is also possible to
supply the pilot system externally.
The hydraulic remote control can also be
con gured both for internal and external pilot
supply.
Accessories
l A wide choice of spools and spool controls
for different  ow combinations and for
several applications and systems
l A full range of secondary valves
l Possibility of high pressure carry-over
l Inlet with electrical unloading valve
l Manual versions easily convertible to
remote control
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Pressure drop
Oil temperature / viscosity for all graphs: +40 °C / 32 cSt
Pressure drop P - T, unloaded valve in inlet I11B and I21B
10 sect.
1 sect.
1 sect.
10 sect.
I11B
I21B
Pressure drop P - T without  ow regulator
∆p (bar) ∆p (bar)
∆p (bar)∆p (bar)
∆p (bar)
Q l/min Q l/min
Q l/min
Q l/min
Q l/min
Pp
G ¼"
A-side
G ¾"
PM1
G ¼"
T3
G 1"
TP
G ¼"
T2
G 1¼"
T1
G 1"
T4
G 1"
P1
G ¾"
Secondary
valve
Outlet
Solenoid
operated
valve
Unloading
Unit
Spool
Control
A-side
Load
Check
Valve
y
G ¼"
x
G ¼"
Spool
Control
B-side
By pass unit
Pilot relief
valve
Secondary
valve port plug
B-side
G ¾"
TD5
P2
G ¾"
Metering ori ce
Back up
unit
Inlet
Back up
valve
Pressure
reducing
valve
The drawing shows a 4-sectional valve
with inlet and outlet. The sections are
with various types of spool controls.
Pressure drop A /B - T
Pressure drop P - A/B
General overview
Pressure drop P-T with  ow regulator
and metering ori ce PF60
10 sect.
1 sect.
10 sect.
1 sect.
Note: The pressure drop curves are valid for
sections equipped with spools that are fully
open at maximum spool travel.
10 sect.
1 sect.
Pressure drop P - T with  ow regulator and
metering ori ce PF30
∆p (bar)
Q l/min
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Measurements spool controls
44
68
44
M10x1.5 (x4)
76
72
LF
L
48 48 34
146
41.5
126.5
217.5
105
7053.5
85(233)
777
2020
98
33
105
275
(445)
4040
4
9
52
56
85
52
(63.5)
48 4548 57
Weight
Inlet section I11B 6.5 kg
Inlet section I21B 5.5 kg
Working section 5.5 kg
Outlet section 7.0 kg
Outlet and workingsection US 6.5 kg
Mid-outlet section 7.0 kg
No. of working sections L [mm] LF [mm]
1 194 106
2 242 154
3 290 202
4 338 250
5 386 298
6 434 346
7 482 394
8 530 442
9 578 490
10 626 538
15°
15°
15°
P1
G ¾"
T1
G 1"
A-side
G ¾"
T3
G 1"
TP
G ¼"
TD5
Inside
T2
G 1¼"
B-side
G ¾"
x
G ¼"
y
G ¼"
P2
G ¾"
T4
G 1"
58
52.5
48
The drawing shows a 4-sectional
valve with inlet and outlet. The valve
is con gured for left hand inlet and
shows the sizes of the ports for a
valve with G-ports and the drawing
also shows the marking of the ports.
Type LA mm Type LB mm
9M1 42 M1 85
9MO1 42 MO3 53
9R1 42 MO3F 53
11M1 74 H1 85
11MO1 74 H1F 85
11R1 95 EHM112 85
SM11 90 EHM124 85
SM21 109 EHM112F 85
SMO11 90 EHM124F 85
SMO21 109
SR11 90
SR21 109
LALB
Dimensions and weight
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Dimensions and weight
33
57
5
33
72
LF
L
48
M10x1.5 (x4)
146
126.585
52 56 29
77
77
20
20
76
264
85
40
41
40
49
5252
33
(8)
48 48 59
P1
G ¾"
T3
G ¾"
T1
G 1"
A-side
G ¾"
A-side
G ¾"
PM1
G ¼"
P2
G ¾"
72
No. of working sections L [mm] LF [mm]
1 140 58
2 188 106
3 236 154
4 284 202
5 332 250
6 380 298
7 428 346
8 476 394
9 524 442
10 572 490
The drawing shows a 4-section
valve with standard inlet section,
working sections manual operated
and a multisection / outlet.
27
Ø 8 Ø 8
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Inlet section I21B
The standard inlet section I21B has 2 pump connections
P1 and P2, a gauge port PM1 to monitor system pressure and
a tank connection T1. Direct acting main relief valve (TBD201),
and an unloading function via 2/2 solenoid valve (EU)
for emergency dump of pump  ow. The cavity (4) can be
used to separate the parallel gallery from the center gallery
to accomplish systems with parallel connection downstream
of another valve or to control a variable pump.
Main relief function
TBD201 is adjustable and sealable for setting range 40 – 300 bar
(4.0 – 30.0 MPa) with setting step 10 bar.
Unloading valve EU12 and EU24
EU12 and EU24 are 2-way, normally open, solenoid type
cartridge valves. It is an option in all inlet sections.
It is intended for emergency stop and for pressure drop / heat
generation reduction.
Rated  ow: 150 l/min up to 280 bar
Rated  ow: 100 l/min up to 350 bar
Power consumption: 18 W
Rated voltage EU12: 12 V
Rated voltage EU24: 24 V
Max voltage variation: +/-15 %
Duty factor*: 100 %
Connection: EN 175301-803 form A
Protection class: IP65
*
Suf cient cooling must be secured.
The unloading valve has manual override, with twist pin operation.
PE21 is the plug for the cavity.
1 Inlet section I21B
2 Unloading valve EU24
3 Relief valve TBD201
4 Cavity for plug PM02 N/A
P1
P2
T1
PM1
PM1
G ¼"
P2
G ¾"
P1
G ¾"
T1
G 1"
∆p (bar)
Q l/min
2
2
3
3
4
4
1
1
Characteristic main relief function (TBD201)
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Inlet section I11B
Flow control function
The inlet section I11B with its integral Q-function provides by-
pass of pump  ow to tank in idling condition, thereby reducing
pressure drop and heat generation. It also reduces  ow forces
and makes the control response to large extent unaffected by
varying pump  ows. This contributes to the excellent operating
characteristics achievable with DX-6.
The regulated  ow into the center gallery is set by an
exchangeable metering ori ce (4).
In case the I11B inlet section is con gured with metering ori ce
PF60, this ori ce determines the high pressure carry-over  ow to
downstream arrangements.
Unloading function
An unloading spool along with an electrical operated pilot valve
forms the unloading function. The unloading spool both unloads
the pump  ow to tank and as well disconnects the valve's parallel
gallery from the pump.
Together with a load holding valve, DX-6 achieves a very safe
emergency dump of pump  ow to tank.
E912 and E926 are 2-way, normally open, solenoid type cartridge
valves. It is an option in all inlet sections. It is intended for emer-
gency stop and for pressure drop / heat generation reduction.
Rated  ow: 40 l/min
Power consumption: 18 W
Rated voltage E912: 12 V
Rated voltage E926: 24 V
Max voltage variation: +/-15 %
Duty factor*: 100 %
Connection: EN 175301-803 form A
Protection class: IP65
* Suf cient cooling must be secured.
The unloading valve has manual override, with twist pin operation.
PE20 is the plug for the cavity.
Main relief function
The by pass unit FK29 in combination with the relief valve
TB 12 form the pilot operated relief valve function.
TB12 is adjustable and sealable for setting range 40 – 350 bar
(4.0 – 35.0 MPa) with setting step 10 bar.
PM1
P1
P2
T1
1 Inlet section I11B
2 Unloading unit FU29
3 Solenoid operated valve E926
4 Metering ori ce for center gallery  ow PF60
5 By-pass  ow control unit FK29
6 Pilot relief valve TB12
PM1
G ¼"
P2
G ¾"
P1
G ¾"
T1
G 1"
∆p (bar)
Q l/min
Characteristics main relief function
Characteristics regulated  ow
Q l/min
Pump  ow l/min
PF60
PF30
2
2
3
3
5
5
4
4
1
1
6
6
Oil temperature / viscosity for all graphs: +40 °C / 32 cSt
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Working section S12L
Working section S22L
Working section S12L for both manual and remote operation.
The example shows a section con gured for manual operation
with the spring centering spool control on A-side and
encapsulated lever mechanism on B-side.
The section S12L includes a load check valve.
Working section S22L for both manual and remote operation.
The example shows a section con gured for hydraulic remote
control with the spring centering spool control on A-side and the
ports for control pressure on the B-side.
The section S22L includes load check valve and cavities for
secondary valves of type TBD/TBSD205.
1 Working section S12L
2 Spool 1XY
3 Load check valve MF29
4 Spool control, A-side 9M1
5 Spool control, B-side M1
1 Working section S22L
2 Spool 1XY
3 Secondary valve TSBD205
4 Load check valve MB29
5 Secondary valve port plug P204
6 Spool control, A-side 9R1
7 Spool control, B-side H1
A-side
G ¾"
B-side
G ¾"
A B
A B
A-side
G ¾"
B-side
G ¾"
x
y
5
2
3
3
4
4
5
1
1
4
4
3
3
5
5
7
7
2
6
6
1
1
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Working section S32L
Working section S32L for both manual and remote operation.
The example shows a section con gured for electro-hydraulic
remote control with the spring centering spool control on A-side
and the proportional solenoids on the B-side.
The section S32L includes load check valve and cavities
for secondary valves of type TBSD280.
1 Working section S32L
2 Spool 1XY
3 Secondary valve TSBD280
4 Load check valve MB29
5 Secondary valve port plug P280
6 Spool control, A-side 9R1
7 Spool control, B-side EH1XX
Load check valve
The main function of the load check valve is to prevent
the load from moving backwards if the load pressure is higher
than pump pressure when operating.
MB29
Load check valve.
MF29
Load check valve with adjustable  ow limitation.
MF29 restricts the  ow out from a section.
Typical application is a slewing function.
A-side
G ¾"
B-side
G ¾"
A B
4
3
5
7
6
1
4
3
5
7
2
6
1
MF29
MB29
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The standard outlet section U11B has 3 tank connection ports
T2, T3 and T4.
Port T3 is used for high pressure carry-over function (HPCO)
when plug S29 is installed in the S1 cavity (see example).
The outlet section U11L with integrated pilot pressure supply for
a valve with electro-hydraulic remote controlled working sections.
Same con guration can be used for pilot pressure supply, via
port Pp, to a hydraulic controller for use with hydraulic remote
controlled working sections.
To ensure suf cient pressure for the pilot circuit a start up
pressure is generated by the back up valve BUP14 installed in
cavity 2. The back up valve can be used in combination with
HPCO plug S29. A pressure reducing valve TRA63 limits the
pressure in the pilot circuit.
Because the pilot pressure is supplied from the parallel gallery an
emergency stop will also unload the pilot pressure.
It is recommended to drain the return  ow in the pilot circuit via
port Tp direct to tank in separate piping. This is accomplished
by PMS5 installed in cavity 6. Note: The port Tp must not be
plugged when PMS5 is installed.
The outlet section U11L can be con gured with a back up valve
(BUP14 installed in cavity 3) for an increased pressure in the
return passage to prevent cavitation in severe conditions.
This is accomplished without compromising the pressure drop
P – T at idling.
Outlet section U11B
Outlet section U11L
T3
T3 TP
T2
T4
T2
T4
T2
G 1 ¼"
T2
G 1 ¼"
TD5
M 5
TP
G ¼"
T3
G 1"
T3
G 1"
S1
G ¾"
S1
G ¾"
T4
G 1"
T4
G 1"
1 Outlet section U11B
2 Carry-over plug S29
1 Outlet section U11L
2 Back up valve BUP14
3 Cavity for back up valve BUP14 for anticavitation
4 Pressure reducing valve TRA63
5 Carry-over plug S29
6 Plug for pilot drain PMS5
2
2
1
1
Pp
2
5
3
6
4
4
6
3
5
2
1
1
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The US22L is an outlet section with integrated spool section,
T3 port for tank connection for both manual operation and remote
control with external pilot pressure supply. High pressure carry-
over function is achieved with SG31 installed in port T3.
Pp – supplied pilot pressure, Tp – pilot drain.
The mid-outlet section N11B with integrated pilot pressure supply
for a valve with electro-hydraulic remote controlled working
sections. Same con guration can be used for pilot pressure
supply, via port Pp, to a hydraulic controller for use with hydraulic
remote controlled working sections.
To ensure suf cient pressure for the pilot circuit a start up
pressure is generated upstream of the mid-outlet by the back up
valve BUP14 installed in cavity 3. The back up valve can be used
in combination with HPCO plug S29. A pressure reducing valve
TRA63 limits the pressure in the pilot circuit.
Because the pilot pressure is supplied from the parallel gallery an
emergency stop will also unload the pilot pressure.
It is recommended to drain the return  ow in the pilot circuit via
port Tp direct to tank in separate piping. This is accomplished
by PMS5 installed in cavity 5. Note: The port Tp must not be
plugged when PMS5 is installed.
A
T3
B
TP
T3
Pp
Tp
T2
Pp
1 Outlet and working section US22L
2 Spool 1XY
3 Secondary valve TBSD205
4 Load check valve MB29
5 Secondary valve port plug TBSD205
6 Spool control, A-side 9R1
7 Spool control, B-side EH1XX
1 Pressure reducing valve TRA63
2 Mid-outlet section N11B
3 Back up valve BUP14
4 Cavity for back up valve BUP14 for anticavitation
5 Plug for pilot drain PMS5
6 Carry-over plug S29
2
6
3
6
5
4
3
4
5
2
Outlet and working section US22L
Mid-outlet N11B
Pp
G ¼"
T2
G 1 ¼"
TP
G ¼"
TP
G ¼"
T3
G 1"
T3
G 1"
A-side
G ¾"
B-side
G ¾"
S1
G ¾"
TD5
M 5
6
3
7
7
5
4
1
6
4
5
3
1
1
2
1
The mid-outlet section N11B can be con gured with a back up
valve (BUP14 installed in cavity 4) for an increased pressure in the
return passage to prevent cavitation in severe conditions. This is
accomplished without compromising the pressure drop P – T at idling.
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Spool controls A-side Spool controls B-side
The spool controls are designed in a modular system for a high
degree of  exibility.
The sections are basically symmetric but as standard machined
either for left or right hand inlet with spool controls on A-side and
B-side.
Spool control 9
9M1:
Manual spring centered 3 pos.
encapsulated.
9MO1:
Manual spring centered 3 pos.
open spool ends.
9R1:
Remote spring centered 3 pos.
Spool control 11
11M1:
Manual spring centered 4 pos.
encapsulated.
11MO1:
Manual spring centered 4 pos.
open spool ends.
11R1:
Remote spring centered 4 pos.
Spool control S*
SM11:
Manual spring centered 3 pos.
spool position indicator.
SMO11:
Manual spring centered 3 pos.
open spool ends spool position
indicator.
SR11:
Remote spring centered 3 pos.
spool position indicator.
Remote spool controls can be with or without manual override.
The valve is, as standard setup for both manual and remote
control.
Spool control M
M1:
for manual lever 3 pos.
MO3:
for manual lever 3 pos. open
spool ends.
MO3F:
for manual lever 4 pos.
open spool ends.
Spool control H
H1:
Hydraulically 3 pos. manual
override available as option
(H1M1).
H1F: Hydraulically 4 pos. manual
override available as option
(H1M1F).
Spool control EHM
EHM1**:
Electro-hydraulically manual
override 3 pos., without manual
override as option (EH1**).
EHM**F:
Electro-hydraulically manual
override 4 pos., without manual
override as option (EH1**F).
* Standard connector M12x1, also available in Deutsch connector.
** 12 or 24 V DC.
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Solenoid valve for EHP – ER12 / 24
The solenoid valves are 3/2-way electrically operated pressure reducing
valves used to provide controlled pilot pressure to operate valve spools.
Functional principle: PWM (Pulse Width Modulation)
Duty factor: 100 %
Connection: AMP Junior-Power-Timer
Recommended PMW frequency: 100 Hz
Protection class: IP 65
Ambient temperature: -30 °C up to + 80 °C
ER12
Rated voltage: 12 V DC
Starting current: 600 mA
Fully shifted: 1,500 mA
Coil resistance +20 °C: 4.72 Ohm
ER24
Rated voltage: 24 V DC
Starting current: 300 mA
Fully shifted: 750 mA
Coil resistance +20 °C 20.8 Ohm
Levers
Lever LH190
The lever holder LH is for use together
with spool control of type M1/EHM.
The lever holder LH can be delivered separate
or in combination with a lever.
Lever MV/MH
Lever for use in combination with open spool ends
and a bracket M03/M03F. When mounted on a valve,
the lever MH stands in a horizontal position and MV
stands in a vertical position.
Lever length 145 or 245 mm.
Lever holder LH
MH245
Lever LH190
MV245
MH245
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Spools – main design parameters
Generally the spools are divided in 3 different ow ranges.
The position indicating regulated ow range is replaced by X,
0 = full pump ow, 3 = 30 l/min and 6 = 60 l/min.
The position indicating pump ow is replaced by Y, 3 = 80 l/min,
4 = 110 l/min and 6 = 160 l/min.
The last three positions in the code are design parameters.
In the table only the accessibility of different functions are shown.
Pos. 1 – Functionality
Spools for general use
Function Code
Double acting 1XY
Single acting 2XY
Double acting, 4
th
pos. for oat 3XY
Motor spool A/B – T 4XY
Regenerative 8XY
Pos. 2 – Regulated center ow – X in the code above
0 = Full pump ow i. e. no regulated ow
3 = 30 l/min regulated ow (use with inlet section I11B)
6 = 60 l/min regulated ow (use with inlet section I11B)
Pos. 3 – Pump ow supplied – Y in the code above
3 = 80 l/min +/-10 l/min
4 = 110 l/min +/-20 l/min
6 = 160 l/min +/-30 l/min
Example:
Spool 136xxx – double acting spool with 30 l/min regulated ow and
160 l/min pump ow, xxx in the code are design parameter.
The DX-6 spools are available in a variety of ows and styles to accommodate most
design requirements. Since the development of spools is a continous process and all
available spools are not described in this data sheet, contact HYDAC for advice on
choosing spools in order to optimize your valve conguration.
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Secondary valves
Port relief valve
TBD205
TBD205 is a differential area,
direct acting relief valve, for
the secondary circuit. It is
adjustable and sealable.
Setting range for TBD205:
l 40 – 300 bar
(4.0 – 30.0 MPa)
l Setting range step: 10 bar
Port relief and
anticavitation valve
TBSD205
TBSD205 is a differential
area, direct acting relief
and anticavitation valve, for
the secondary circuit. It is
adjustable and sealable.
Setting ranges for TBSD205:
l 40 – 300 bar
(4.0 – 30.0 MPa)
l Setting range step: 10 bar
Port relief and
anticavitation valve
TBSD280
TBSD280 is a direct acting
relief and anticavitation valve,
for the secondary circuit. It is
xed and sealable.
Setting ranges for TBSD280:
l 90 – 400 bar
(9.0 – 40.0 MPa)
l Setting range step: 10 bar
Anticavitation valve
SB204
The anticavitation valve
ensures that, in the event of a
lower pressure in the cylinder
port than in the tank, oil can be
drawn from the system oil tank
to the consumer.
∆p (bar)
∆p (bar)
∆p (bar)
∆p (bar)
Q l/min
Q l/min
Q l/min
Q l/min
Relief characteristics TBD205
Relief characteristics TBSD205
Relief characteristics TBSD280
Anticavitation characteristics
TBSD205 and SB204
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Secondary valves
Anticavitation valve
SB280
The anticavitation valve
ensures that, in the event of a
lower pressure in the cylinder
port than in the tank, oil can
be drawn from the system oil
tank to the consumer.
∆p (bar)
Q l/min
Anticavitation characteristics
TBSD280 and SB280
Typical hydraulic diagrams
This example shows a DX-6 hydraulic diagram with:
the inlet section with  ow control function and electrical unloading. A metering ori ce determines the center gallery  ow.
A pilot operated relief valve in combination with the  ow control performs the main relief valve function.
4 working sections all with double acting cylinder spools hydraulically actuated. Section 3 with a spool position indicator.
Outlet section machined for pilot pressure supply, back up pressure and high pressure carry-over (HPCO)
but in the example con gured with cavity plugs.
This example shows a DX-6 hydraulic diagram with:
the inlet section of standard type with a direct acting main relief valve.
5 working sections all manual operated. Section 3 with 3-position regenerative spool.
The outlet section with integrated working section with option for HPCO.
31-02-DX-6-01/ 09.14
16
Note
The information in this brochure
relates to the operating conditions
and applications described.
For applications or operating
conditions not described, please
contact the relevant technical department.
Subject to technical modications.
Head Ofce Industriegebiet
HYDAC INTERNATIONAL 66380 Sulzbach/Saar
GMBH Germany
Phone: +49 6897 509 -01
Fax: +49 6897 509- 577
E-mail: mobilevalves@hydac.com
Internet: www.hydac.com