1/5
Type series: SMDR-_-6-…
Reference: 400-P-430101-EN-03/04.2024
- Stack valve
- Interface to ISO 4401-03-02
- External parts of screw-in valves with zinc-nickel
plating according to DIN EN ISO 19598
- Stack-mounting body with temporary corrosion
protection
Flow valve
Throttle check valve
Q
max
= 80 l/min, p
max
= 350 bar
direct acting, spool type
Type series: SMDR-_-6-…
Description
The throttle check valves, series SMDR…, are size 6,
direct acting stack valves with interface to ISO 4401-
03-02. They are designed on the proven sliding-spool
principle. The integral check function allows free ow
in one direction (opening pressure approx. 0.7 bar)
and the set, throttled ow in the opposite direction.
The design of the throttle ensures automatic self-cle-
aning under reverse ow. The setting is made at the
self-locking adjusting screw and can be additionally
secured with the lock nut. There are dierent versions
available. These valves are mainly used in mobile and
industrial applications, and provide high exibility for
stackable system solutions. For installation, please re-
fer to the section related data sheets.
Symbol
PTBA
SMDR-AZ-…
PTBA
SMDR-ABZ-…
PT
BA
SMDR-BZ-…
PTBA
SMDR-AA-…
PTB A
SMDR-ABA-…
PT
BA
SMDR-BA-…
- Stackable valve elements
- High degree of exibility due to the possibility of
dierent combinations
2/5
Type series: SMDR-_-6-…
Reference: 400-P-430101-EN-03/04.2024
Technical data
General characteristics Description, value, unit
Function group Flow valve
Function Throttle check valve
Design Stack valve
Characteristic direct acting, spool type
Construction size NG 6
Mounting attitude unrestricted
Weight 1.30 kg
Interface according to ISO 4401-03-02
Minimum ambient temperature - 30 °C
Maximum ambient temperature + 80 °C
Surface protection
External parts of screw-in valves with zinc-nickel plating
according to DIN EN ISO 19598
Surface protection addition Stack-mounting body with temporary corrosion protection
Sealing material see ordering code
Seal kit order number NBR: DS-202-N / FKM: DS-202-V
Hydraulic characteristics Description, value, unit
Maximum operating pressure 350 bar
Maximum ow rate 80 l/min
Flow direction see symbol
Hydraulic uid
HL and HLP mineral oil according to DIN 51 524; other uids
on request!
Minimum uid temperature - 30 °C
Maximum uid temperature + 80 °C
Viscosity range 10 … 650 mm²/s (cSt)
Recommended viscosity range 15 … 250 mm²/s (cSt)
Minimum uid cleanliness (cleanlineless class according to ISO
4406:1999)
class 20/18/15
3/5
Performance graphs
measured with oil viscosity 33.0 mm²/s (cSt)
Δp = f (Q) Pressure drop-ow rate characteristic Δp = f (Q) Pressure drop-ow rate characteristic
20 30100405060
Q [l/min (gpm)]
(15)(5)(7.5) (10) (13)(2.5)
4 (60)
12 (170)
16 (230)
20 (285)
0
p = [bar (psi)]
∆
400-PG-0682
8 (120)
70
(18)
80
(21)
1) 2)
1) through check valve: throttle cosed
2) through check valve: throttle open
0.510.20.13
58
0
Q [l/min (gpm)]
(21)(0.13) (0.25) (0.75)(1.25)(0.052)
50 (700)
150 (2100)
200 (2900)
250 (3600)
0
p = [bar (psi)]
∆
400-PG-0684
100 (1400)
at constant throttle setting
2
(0.5)
10
(2.5)
20
(5)
50
(13)
(0.025)
0
2
2.5 3456 7
8
Throttle closed
[leakage 0,1...0,2 l/min]
Throttle closed
(in turns of adj. screw)
Type series: SMDR-_-6-…
Reference: 400-P-430101-EN-03/04.2024
4/5
Type series: SMDR-_-6-…
Reference: 400-P-430101-EN-03/04.2024
Dimensions and sectional view
39.95
(1.57)
16.15
(.64)
39.95
(1.57)
25.05
(.99)
1.25
(.05)
Funktion (Drosselung) im Zulauf / function (throtteling) in inlet
Dichtblech mit 4 O-Ringen im Lieferumfang enthalten /
Seal plate with 4 O-rings included in the delivery
Funktion (Drosselung) im Ablauf / function (throtteling) in outlet
40.5
(1.59)
46
(1.81)
23
(.91)
31
(1.22)
27.55
(1.08)
max. 37
(max. 1.46)
max. 37
(max. 1.46)
6.55
(.26)
6.55
(.26)
98
(3.86)
7.5
(.30)
SMDR-B_-6-S...:141.55
(5.57)
SMDR-A_-6-S...:141.55
SMDR-AB_-6-S...:172
(6.77)
13
4
T
P
A B
max. 39.6
(max. 1.56)
Ø25
(Ø.98)
13
2
Option Handrad "HF" /
Option hand-knob "HF"
Option Handrad arretierbar "HA" /
Option hand-knob lockable "HA"
max. 39.6
(max. 1.56)
Ø25
(Ø.98)
Ø9.25×1.78
4×
(5.57)
Beispiel für die Masseinheit:
Example for the dimensional units:
5/5
Type series: SMDR-_-6-…
Reference: 400-P-430101-EN-03/04.2024
ATTENTION!
Only qualied personnel with mechanical
skills may carry out any maintenance work.
Generally, the only work that should ever be
undertaken is to check, and possibly replace,
the seals. When changing seals, oil or grease
the new seals thoroughly before tting them.
Ordering code
S
= stack valve
Ex.
M
= flow-control valve
1
A
N
_
-
S6-
S AA -
6
= nominal size 6
S
= screw adjuster (standard)
BZN
= coating ZnNi (on request)
N
= NBR (nitril-butadien-rubber / BUNA) seals (standard)
V
= FKM (fluorocarbon rubber / VITON) seals
(special seals - please contact BUCHER)
1…9 = design stage (omit when ordering new units)
--
AA = function in A, throttling in outlet
AZ
= function in A, throttling in inlet
BA
= function in B, throttling in outlet
BZ
= function in B, throttling in inlet
ABA
= function in A and B, throttling in outlet
ABZ
= function in A and B, throttling in inlet
(blank)
= temporary corrosion protection (standard)
A…Q
= standard model - see relevant data sheets
Z…R
= special features - pleace consult BUCHER
M
D
= throttle valve
D R
R = check valve function
SF
= screw adjuster, fine opening
H
= hand-knob adjuster
HF
= hand-knob adjuster, fine opening
Related data sheets
Reference Description
400-P-030501 Interface ISO 03 (Size 6) according to ISO 4401-03-02
info.ch@bucherhydraulics.com www.bucherhydraulics.com
© 2024 by Bucher Hydraulics AG Frutigen, 3714 Frutigen, Switzerland
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.
Installation information