26 89

Industrial
Hydraulics
Electric Drives
and Controls
RE 26 893/02.03
Replaces: 11.02
Pressure reducing valve,
pilot operated
Type DR
Overview of contents
Linear Motion and
Assembly Technologies Pneumatics
K 4661-5
Nominal sizes 10 and 25
DR 20 G-4-4X/..
Series 4X
Maximum operating pressure 315 bar
Maximum flow 160 L/min
Contents Page
Features 1
Ordering details 2
Symbols 2
Preferred types 2
Function, section 3
Technical data 4
Characteristic curves 5
Unit dimensions 6 to 8
Service
Automation
Features
Mobile
Hydraulics
DR 20 K-5-1X/..
– For subplate mounting:
Porting pattern to DIN 24 340, Form D, ISO 5781
and CETOP-RP 121 H,
Subplates to catalogue sheet RE 45 062
(separate order),
– For threaded connections,
– Cartridge version,
– 4 adjustment elements:
• Rotary knob
• Sleeve with hexagon and protective cap
• Lockable rotary knob with scale
• Rotary knob with scale
– 4 pressure stages
© 2003
by Bosch Rexroth AG, Industrial Hydraulics, D-97813 Lohr am Main
All rights reserved. No part of this document may be reproduced or stored, processed, duplicated or circulated using
electronic systems, in any form or by means, without the prior written authorisation of Bosch Rexroth AG. In the event
of contravention of the above provisions, the contravening party is obliged to pay compensation.
DR 1/8 RE 26 893/02.03
K 3444/6
K3444/3
DR 10-5-4X/..

Ordering details
Nom. Subplate
Valve for
Version Version
size mounting "G" "K"
10 = 10
Ordering details
= 10 (G 1/2)
= 15 (G 3/4)
–
25 = 20 = 20 (G 1) = 20
For subplate mounting = No code
For threaded connections = G
For manifold mounting (cartridge)
Adjustment element
= K
Rotary knob = 4
Sleeve with hexagon and protective cap = 5
Lockable rotary knob with scale = 6 1)
Rotary knob with scale = 7
1) Key with order no. R900008158
is included within the scope of supply
Symbols
Preferred types (readily available)
Type Material No
DR 10-5-4X/100Y R900402741
DR 10-5-4X/200Y R900402064
DR 10-5-4X/315Y R900479797
DR 10 G5-4X/100YM R900418436
DR 10 G5-4X/315YM R900415481
DR 20-5-4X/100Y R900404828
DR 20-5-4X/200Y R900402753
DR 20-5-4X/315Y R900405904
DR 20 G5-4X/100YM R900417545
DR 20 G5-4X/315YM R900493572
DR – – / Y *
Further details in clear text
No code NBR seals
V = FKM seals
(other seals on request)
Attention!
The compatibility of the seals and pressure
fluid has to be taken into account!
No code = With check valve
(only for the subplate mounting version)
M = Without check valve
50 = Settable pressure up to 50 bar
100 = Settable pressure up to 100 bar
200 = Settable pressure up to 200 bar
315 = Settable pressure up to 315 bar
1X = Series 10 to 19 (only version"K")
(10 to 19: unchanged installation and connection dimensions)
4X = Series 40 to 49
(40 to 49: unchanged installation and connection dimensions)
For subplate mounting For subplate mounting
For threaded connections
mounting
as a cartridge valve
connections
B
A
Y
Type DR...-4X/...Y Type DR...-4X/...YM
Type DR...K.-1X/...YM
(cartridge)
B
A Y B
Type Material No
DR 20 K5-1X/50YM R900474524
DR 20 K5-1X/100YM R900474525
DR 20 K5-1X/200YM R900474526
DR 20 K5-1X/315YM R900474527
Further preferred types and standard units can
be found in the EPS (Standard Price List).
RE 26 893/02.03 2/8 DR
A
Y
Type DR...G.-4X/...YM

Function, section
The pressure control valve type DR, series 4X, is a, cartridge
version, pilot operated pressure reducing valve. It is used to reduce
pressure in a system.
The pressure reducing valve comprises of the cartridge and a
housing, optionally with or without a check valve (only for the
subplate mounting version).
Pressure reducing valves types DR 10 and DR 20
At rest the valve is open. The pressure fluid can pass unhindered
from the inlet port via the main spool (1) to the outlet port. The
pressure in the output port is applied via the drilling (2) onto the
spring loaded side of the main spool assembly (1). At the same
time the pressure acts on the spring at the opposite end of the
main spool (1) via drillings (3) and (4).
If the pressure in the output port rises above the value set at
spring (6), then the pilot poppet (5) opens. Pressure fluid flows
from the spring loaded side of the main spool (1) via orifice (7) and
the pilot poppet (5) into the spring chamber (8).
8 6 5 7 10 4 3 1
9 Y A 2
B
The main spool (1) moves into its control position and maintains
the value set at the spring (6) in the outlet port. Pilot oil return
from the spring chamber (8) is always external via port Y (9).
For the subplate mounting version an optional check valve (10) can
be fitted to permit free-flow from port A to B.
Remote control
The types DR 10 and DR 20, series 4X, pressure reducing valves
can only be remotely controlled via port Y.
DR 3/8 RE 26 893/02.03
5
7
2
A A
B
Y
8
6
9
4
3
1

Technical data (for applications outside these parameters, please consult us!)
General
Installation Optional
Ambient temperature range °C – 30 … + 80 with NBR seals
°C – 20 … + 80 with FKM seals
Nominal size NS 10 25
Weight Subplate mounting kg 3.2 3.5
Hydraulic
Threaded connections kg 3.6 3.3
Cartridge valve kg 2.5 2.8
Nominal pressure bar 315
Maximum operating pressure (inlet) bar 315
Maximum secondary pressure (outlet) bar 50; 100; 200; 315
Maximum back pressure in port Y bar 250
Settable pressure Minimum bar Flow dependent (see characteristic curves on page 5)
Maximum bar 50; 100; 200; 315
Maximum flow Subplate mounting L/min 80 160
Threaded connection L/min 80 160
Pressure fluid Mineral oil (HL, HLP) to DIN 51 524 2) ;
Fast bio-degradable pressure fluids to
VDMA 24 568 (also see RE 90 221); HETG (rape seed oil) 1) ;
HEPG (polyglycole) 2) ; HEES (Synthetic ester) 2) ;
other pressure fluids on request
Pressure fluid temperature range °C – 30 … + 80 with NBR seals
°C – 20 … + 80 with FKM seals
Viscosity range mm2 /s 10 … 800
ISO code cleanliness class Maximum permissible degree of contamination of the pressure
fluid is to ISO 4406 (C) class 20/18/15 3)
1) Suitable for NBR and FKM seals
2) Only suitable for FKM seals
3) The cleanliness class stated for the components must be adhered too in hydraulic systems. Effective filtration prevents faults from
occurring and at the same time increases the component service life.
For the selection of filters see catalogue sheets RE 50 070, RE 50 076 and RE 50 081.
RE 26 893/02.03 4/8 DR

Characteristic curves (measured with HLP46, ϑ oil = 40 °C ± 5 °C)
Outlet pressure in bar →
Control flow in L/min →
Min. pressure differential in bar →
Pressure differential in bar →
Outlet pressure pA in relationship to the
flow qV (B to A)
315
250
200
150
100
14
12
10
50
1,50
1,25
1,0
0,75
0,50
0,25
0 20 40 60 80 100 120 140 160
Flow in L/min →
8
6
4
2
0 20 40 60 80 100 120 140 160
Flow in L/min →
7
6
5
4
3
2
1
NG 10 NG 25
0 20 40 60 80 100 120 140 160
3
NS NG 10 NG NS 25
4
Minimum settable pressure p A min
related to the flow q V (B to A)
Flow in L/min → Flow in L/min →
NS NG 10 NS NG 25
Dp= 250 bar
Dp= 50 bar
NS NG 10 NS NG 25
0 20 40 60 80 100 120 140 160
Outlet pressure in bar →
30
25
20
15
10
5
NG 10 NG 25
0 20 40 60 80 100 120 140 160
Control flow q V st in relationship to the flow q V (B to A) and to the pressure differential ∆p
∆p min -q V - characteristic curves (B to A)
∆p min -q V - characteristic curves (B to A)
Flow in L/min →
DR 5/8 RE 26 893/02.03
1
5
6
2
Performance limit
(dependent on the
system):
1 NS 10
2 NS 25
3 and 4 NS 10
5 and 6 NS 25
3 and 5:
Main stage closed
4 and 6:
Main stage fully open

Unit dimensions: for subplate mounting (dimensions in mm)
Ø 32
8 4 3 11
18
2109 8
1 Adjustment element “4”
2 Adjustment element “5”
3 Adjustment element “6”
4 Adjustment element “7”
5 Locknut 22A/F
6 Hexagon 10A/F
7 Hexagon 30A/F
tightening torque
MA = 50 Nm
8 Space required to remove the key
9 Locating pin
10 Valve fixing screw holes
11 Name plate
12 Identical seal rings for ports A and B
13 Seal ring for port Y
Subplates to catalogue sheet RE 45 062
and valve fixing screws
must be ordered separately.
Subplates for
Valve size 10:
G 460/01 (G 3/8)
G 461/01 (G 1/2)
Valve size 20:
G 412/01 (G 3/4)
G 413/01 (G 1)
Valve fixing screws for
Valve size 10:
M10 x 40 DIN 912–10.9, MA = 75 Nm
Valve size 20:
M10 x 50 DIN 912–10.9, MA = 75 Nm
3
76
Ø
100
40
6 2 1 5 7 9 13 12
B1
B2
Ø 30
H4
Required surface finish of the
mating piece
0,01/100mm
R max 4
RE 26 893/02.03 6/8 DR
48
L5
ØD2
ØD3
48
L1
ØD1
A
L6
L4 L3
L2
B
Ø6
Ø17,2
Ø8
Valve type L1 L2 L3 L4 L5 L6 B1 B2 B3 B4 H1 H2
DR 10 95.5 79 42.9 23 2.5 21.5 85 49 66.7 7.9 71 60
DR 20 96 79.5 60.3 7 4 39.7 100 58 79.4 6.4 96 78
Valve type H3 H4 Ø D1 Ø D2 Ø D3
DR 10 26 26 35.5 21.8 15
DR 20 26 40 41 34.8 25
H3
5
B4
H2
4xØ11
B3
H1 5
10

Unit dimensions: for threaded connections (dimensions in mm)
10
Attention!
This valve version does
not include an
integrated check valve
for free return flow.
90
41 45
66
=
=
Valve type D1 Ø D2
DR 10 G G 1/2 34
DR 15 G G 3/4 42
DR 20 G G 1 47
1 Adjustment element “4”
2 Adjustment element “5”
3 Adjustment element “6”
4 Adjustment element “7”
48
Ø9
ØD2; 0,3
D1
ØD2; 0,3
B
ØD2; 0,3
44,5
121
A
66
45
Ø25
D1
DR 7/8 RE 26 893/02.03
Y
A
35 31 D1
5 Locknut 22A/F
6 Hexagon 10A/F
7 Hexagon 30A/F
tightening torque
MA = 50 Nm
G 1/4; 12
40
48
3
76
8 9 0 1 2
33
Ø 30
Ø 35
74
100 18
Ø 32
5
1
7
14
11
8 Space required to remove the key
10 Valve fixing screw holes
11 Name plate
14 Port Y for pilot oil drain
2
6
4
8
3

Unit dimensions: for manifold mounting (dimensions in mm)
4
16
17
16
76
Ø 32
2 1 0 9
1 Adjustment element “4”
2 Adjustment element “5”
3 Adjustment element “6”
4 Adjustment element “7”
5 Locknut 22A/F
6 Hexagon 10A/F
7 Hexagon 30A/F
tightening torque MA = 50 Nm
8 Space required to remove the
key
16 Seal ring
17 Back-up ring
18 Depth of fit
19 Connection bores A, B and Y
positioned as required around
circumference
3
Bosch Rexroth AG
Industrial Hydraulics
D-97813 Lohr am Main
Zum Eisengießer 1 • D-97816 Lohr am Main
Telefon 0 93 52 / 18-0
Telefax 0 93 52 / 18-23 58 • Telex 6 89 418-0
eMail documentation@boschrexroth.de
Internet www.boschrexroth.de
8
100 18
84
8
3
0,02 A
84±0,2
6
18
66
16,5
64,5
42
12
18
max. Ø12
max. Ø12
Ø 35
19
Y = Rz
Ø4
40
0,03 B
Y
A
Bosch Rexroth Limited
Cromwell Road, St Neots
Cambs, PE19 2ES
Tel: 0 14 80/22 32 56
Fax: 0 14 80/21 90 52
E-mail: info@boschrexroth.co.uk
Z
The data specified above only serves to describe
the product. No statements concerning a certain
condition or suitability for a certain application can
be derived from our information. The details stated
do not release you from the responsibility for
carrying out your own assessment and verification.
It must be remembered that our products are
subject to a natural process of wear and ageing.
RE 26 893/02.03 8/8 DR
Ø 30
2 5 1
B
Z = Rz1
Cavity
7
M28x1,5
48
Ø29 H8 20°
Ø26,5
Ø24 +0,1
Z
Ø22,5 H8
Ø30
Ø8
Z
20°
20°
Ø20,8 +0,2
Ø21 H8
Ø28
Y
Y
Z
A
Z
10°
2,5
8
19
28,5 +0,2
35 +0,2
0,03 A
56 +0,2
0,03 A