EN 5.169.21.1/05.25
1
PRODUCT ADVANTAGES
z Max. accumulator charge pressure can be set with various xed switching pressure
dierences
z Low leakage for energy-ecient circuit
z External surfaces with advanced corrosion protection thanks to
ZnNi coating (1,000 h salt spray test)
DESCRIPTION OF FUNCTION
The HYDAC DLM12121P-01 accumulator charging valve is a pilot operated spool valve.
When the accumulator is unloaded at port 1, the valve switches on the pump pressure to
charge the accumulator. Once the maximum accumulator pressure (the valve’s setting
pressure) has been reached, the valve relieves the pump pressure to the tank (port 2)
and stops the accumulator charging.
To enable this, the current accumulator pressure is reported back to port 3. If the actuator
empties the accumulator, the pressure at ports 1 and 3 drops.
If the pressure level drops below the switch-on pressure (set pressure minus switching
pressure dierence), the valve switches the pump pressure for accumulator charging
back on. This is performed cyclically and is controlled by the valve.
If it is supported by an external check valve, the accumulator charging function operates
with low leakage.
Note: Pressure at port 2 inuences the switching pressure.
FUNCTION
Accumulator charging valve
DLM12121P-01
Spool type, pilot operated
Screw-in cartridge valve, metric – 350 bar
Application examples: See page 2
Illustration of switching pressure dierence
Pressure p
Flow rate Q
Set pressure
Switch-on pressure
Switching pressure dierence
Limit of application
up to 30 l/min
up to 350 bar
1
1
2
2
3
3
EN 5.169.21.1/05.25
2
+
TECHNICAL CHARACTERISTICS
1)
Operating pressure max. 350 bar max. 5,000 psi
Flow rate max. 30 l/min max. 7.9 gpm
Switching pressure dierence 10% ± 3%
Dierence of switch-o pressure minus switch-on pressure
(max. setting pressure equals 100%)
20% ± 3%
30% ± 3%
Leakage
max. 30 cm³/min. at 350 bar and ν = 32 mm
2
/s | Port 1 → 2, port 3 → 2
Operating uid Hydraulic oil to DIN 51524 Part 1, 2 and 3
Ambient temperature range NBR: min. -30 °C up to max. +100 °C
FKM: min. -20 °C up to max. +120 °C
Temperature range of operating uid NBR: min. -30 °C up to max. +100 °C
FKM: min. -20 °C up to max. +120 °C
Viscosity range min. 10 mm²/s up to max. 420 mm²/s
Filtration Permitted contamination level of the operating uid as dened by ISO 4406
p ≤ 210 bar: min. class 21/19/16
p > 210 bar: min. class 19/17/14
MTTF
D
150 - 1200 years, assessment according to DIN EN ISO 13849-1:2016, Table C.1,
conrmation of ISO 13849-2:2013, Tables C.1 and C.2
Installation User-denable
Materials Valve body: Steel
Seals: NBR (standard)
FKM
Support rings: PTFE
Cavity 12121 metric
weight 0.26 kg
1
See “Conditions and Instructions for Valves” in brochure 53.000
APPLICATION EXAMPLE
Accumulator charging valve
The accumulator charging cycle is determined by the ratio between the pump volume, accumulator unloading volume and accumulator
size. The entire cycle time for charging and discharging the accumulator should be at least 1 second.
The drop-o load of the check valve inuences the accumulator charge pressure. We therefore recommend using a size 12 check
valve.
RV
A
2
3
1
M
T
P
EN 5.169.21.1/05.25
3
CAVITY
VE = Visual Examination
FIitting depth
Fitting depth
EX.:
(Included angle)
Rz 10
Rz 6.3
Ra 6.3
1
±0.2
40.3
26.7
±0.1
60° **
23
H8
38.5
±0.5
51.2
±0.1
60° **
21
H8
62.5
±0.5
64
±0.5
22,5
±1
M27x2
21.3 min.*
26.2 max.*
37.3 min.*
50.7 max.*
8
Max. Nominal-
: 20
37.7
61.7
X
[Ø20±1]
Rz3 10
Rz 6.3
Rz 6.3
Rz 6.3
VE
0.02
0.05
A B
0.05
A B
0.05
A B
PD
A
B
R0.15
±0.05
R0.2
±0.2
3.3
±0.2
30°
±1°
29.45
±0.05
45°
X 4 : 1
Rz2 6.3
0.1
ACS
B
0.05
A B
ACS
1
2
3
12121 metric
*
Permitted boring zone (for block design).
**
Sharp edges should be avoided using a radius of 0.1 mm to 0.2 mm. Millimetre
***
Largest pre-drilling diameter (nominal tool diameter). Subject to technical modications.
EN 5.169.21.1/05.25
4
+
DIMENSIONS
* Tightening torque:
Steel housing burst strength >360 N/mm
2
: 105 Nm | Aluminium housing burst strength >330 N/m
2
: 70 Nm Millimetre
Torque tool acc. to DIN EN ISO 6789, tool type ll class A or B. Subject to technical modications.
M27x2
AF width 32 | HEX 5/4"
Tightening torque*
Ø32
Lock nut for pressure setting
AF width 13 | HEX 1/2"
Tightening torque 6 Nm
CW Increase in setting pressure
AF 4 width | HEX 5/32"
1
2
64
3
47 max.
2
EN 5.169.21.1/05.25
5
MODEL CODE
DLM12121P - 01 - C - N - 10 - 350 V 350
Designation
Accumulator charging valve, metric
Design
01 = Standard
Body and ports
C = Screw-in cartridge valve
Sealing material
N = NBR (standard)
V = FKM
Switching pressure dierence
10% ± 3%
20% ± 3%
30% ± 3%
Pressure setting ranges
350 = up to 350 bar | up to 5,076 psi (Min. setting pressure is dependent on switching pressure dierence).
Adjustment type
V = adjustable using tool
Setting pressure
n/a = no setting, spring relaxed
350 = custom setting pressure
TYPICAL PERFORMANCE CURVES
p/Q characteristics measured at ν = 34 mm
2
/s, T
oil
= 46 °C
Pressure p
[bar] [psi]
0
0
5,000
350
100
50
[gpm]
0 5 10 15 20
[l/min]
0
25 30
Flow rate Q
150
1,000
300
4,000
200
3,000
2,000
1 2 3 4 5 6 7
250
Accumulator charge pressure
EN 5.169.21.1/05.25
6
+
APPLICATIONS
Pressure p
[bar]
0
350
0 5 10 15 20
[l/min]
25 30
Flow rate Q
250
100
50
300
200
150
10% switching pressure dierence
Limit of application
5,000
4,000
3,000
2,000
1,000
0
0 1 2 3
4 5 6
7
[psi]
[gpm]
Pressure p
[bar]
0
350
0 5 10 15 20
[l/min]
25 30
Flow rate Q
250
100
50
300
200
150
30% switching pressure dierence
Limit of application
5,000
4,000
3,000
2,000
1,000
0
0
1
2 3
4 5 6 7
[psi]
[gpm]
Pressure p
[bar]
0
350
0 5 10 15 20
[l/min]
25 30
Flow rate Q
250
100
50
300
200
150
20% switching pressure dierence
Limit of application
5,000
4,000
3,000
2,000
1,000
0
0 1 2 3
4 5 6
7
[psi]
[gpm]
EN 5.169.21.1/05.25
7
MATERIAL OVERVIEW
Standard models
Designation Part no.
DLM12121P-01-C-N-10-350V 3903008
DLM12121P-01-C-N-20-350V 4025835
DLM12121P-01-C-N-30-350V 4025842
Further versions on request.
Spare parts
Designation Material Code Part no.
Seal kit NBR FS metric 12121 /N 3651335
Seal kit FKM FS metric 12121/V 4080086
Housing
Designation Material Code Pressure Connections Weight Part no.
Pipe connection housing Steel, zinc-plated H-R12121-SB6/3 350 bar G3/4" | G3/8" 1.89 kg 3130704
Further versions on request.
Cavity tools
Designation Part no.
Countersink 177317
Reamer 175021
NOTE
The information in this brochure relates to the operating conditions and applications
described. For applications not described, please contact the relevant technical department.
Subject to technical modications.
Only the documents currently available on the website are valid documents.
HYDAC FLUIDTECHNIK GMBH
Justus-von-Liebig-Str.
66280 Sulzbach/Saar
Germany
Phone: +49 68 97 / 509-01
E-mail: valves@hydac.com
Internet: www.hydac.com