High performance directional v alve, ISO size 3
Solenoid controlled, 2-stage
Series WEVDK ...
Reference: 400--P--181410--EN-Ad/09.15
1/4 430.20.60.70
Replaces: W--18 Ac
Classification:
S 350 bar, 100 l/min
S High switching reliability thanks to
spool operation
S Unaffected by:
-- asymmetric flow paths
-- long periods under high pressure
w
-- large pressure drops across
t
he spool lands
-
- low supply voltage
S High flow rates
S Good ∆p -- Q characteristics
S Pressure in P, A and B to 350 bar
S Wet armature design, change
coils without opening hydraulic
envelope
S With manual override
S Mounting interface to ISO 4401 /
CETOP R35H size 3, NFPA D03,
DIN 24 340 A6
1. Description
Series WEVDK ...--6 high performance
spool valves are internally piloted and
use the follower spool principe. The
main valve components are a cast
body, a spring--centered follower spool
assembly and wet ar mature solenoids
with pressure--tight core tube and
slip-- on coil. These valves provide reli-
able service even under the severest
operating conditions such as very high
flow rates, high operating pressures,
supply voltage drops, long periods
without switching, large and sudden
changes in fluid temperature etc. The
highly effective spool actuation method
combines the advantages of direct act-
ing and two-- stage solenoid valves,
without incurring the well known disad-
vantages of either type. The main spool
is offset by both the solenoid force and
the P ⇒ T *) pressure difference inside
the valve. The greater the P ⇒ Tpres-
sure difference, the greater the offset-
ting force. The spool is returned to the
mid--position in the same way, using the
P ⇒ T pressure difference and without
the need for the usual heavy centering
springs. If very low flow rates, or an
open circuit condition, result in there
being no P ⇒ T pressure difference,
then the s pool actuaction reverts to the
normal solenoid / centering spring ar-
rangement. The manual over--ride,
which is fitted as standard equipment
to all valves, can be operated even
when high tank line back-- pressures
exist in the core tube.
*) The pressure in P must always be
equal to, or greater than, that in T and
the valve must be connected in the
conventional manner i.e. pressure to P,
Ttotank.
2. Symbols
1
WEVDK--42--A--6 ... WEVDK--42--AD--6
WEVDK--42--AG--6
WEVDK--42--BD--6
WEVDK--42--BG--6
WEVDK--43--D--6
WEVDK--43--G--6
AB
PT
a
AB
PT
b
AB
PT
a
AB
PT
b
AB
PT
b
a
WEVDK--42--B--6 ...
AB
PT
a
AB
PT
b
AB
PT
b
a
WEVDK--42--AH--6 WEVDK--42--BH--6 WEVDK--43--H--6
A
B
PT
a
A
B
PT
b
A
B
PT
b
a
WEVDK--42--AJ --6 WEVDK--42--BJ --6 WEVDK--43--J--6
AB
PT
a
AB
PT
b
AB
PT
b
a
2
3
4
6
5
7
8
12 16
10
11
14
15
913
WEVDK--42--C--6 ...
AB
PT
a
b
ba
Crossover transients
4/2 FUNCTIONS
4/2 FUNCTIONS
WITH 4/3 SPOOLS
4/2 FUNCTIONS
WITH 4/3 SPOOLS
4/3 FUNCTIONS
400--P--181410--EN--Ad/09.15
2/ 4
3. Characteristics
Type high performance 4/2 and 4/3 directional valve
Design combined direct acting and 2-- stage
Mounting method manifold mounting
Size nominal size 6 mm, ISO 4401 size 3 inter face
Mass kg 1,6 (1 solenoid), 2,1 (2 solenoids)
Mounting attitude unrestricted (Vertical mounting makes air bleeding difficult)
Flow direction see symbols
Operating pressure in P, A und B bar max. 350
Operating pressure in T (static) bar max. 80
Flow rate Qmax l/min 0 ... 100 l/min (see ∆p-- Q characteristics)
Pilot oil consumption P -- > T cm
3
/min at 50 bar = 40; at 200 bar = 100
Fluids Hydraulic oils HL and HLP to DIN 51 524 --
for other fluids consult BUCHER
Fluid temperature range _C --25 ... + 80
Ambient temperature _C --25 ... + 50
Viscosity range cSt 10 ... 500, recommended 15 ... 250
Minimum fluid cleanless 18/14 to ISO 4406 /CETOP RP70H 8 ... 9 to NAS 1638
Standard voltages VAC
VDC
115, 230 40...60 Hz
12, 24
Nom. voltage tolerance % +5/--10
Nom. power consumption VDC 12: 38 W; 24: 32 W
Duty cycle %ED 100
Enclosure protection IP 65 to DIN 40 050
Electrical connection 3--pin square plug to DIN43 650 / ISO 4400
4. Performance graphs
Oil viscosity 36 cSt
100 ... 350 ms
180 ... 550 ms
50
45
40
35
30
25
20
15
10
5
10 20 30 40 50 60 70 80 90 100
123
4
-- --
-- --
-- --
--
A spool
D spool
G spool
H spool
J spool
42 4 2
4---- 4 2
42 4 2
42 4 4
1---- 1 13
Sol. OFF Sol. ON Sol. OFF Sol. ON
-- --
2
2
4
1
-- --
-- --
2
2
-- --
P ⇒ AP⇒ T
B ⇒ TA⇒ T
P ⇒ B
→∆p(bar)
→ Q(l/min)
∆p --Q characteristics
Switching times
measured with:
24 VDC solenoid
5% under-- voltage,
coil at s teady--state
temperature.
Solenoid ON
Solenoid OFF
These are guideline values only, and can be significantly
affected by flow rate and pressure. To achieve switching
times which are largely unaffected by variations in supply
voltage and coil temperature, we recommend our type LRS
Power Reducing connector plug.
Contact BUCHER for application assistance.
400--P--181410--EN--Ad/09.15
3/ 4
5. Dimensions
38
PG 9
SWISS
MADE
A
B
ø45
ca. 94
Solenoid a
4/2 function ”A” valve 4/2 function ”B” valve
PG 9
65,4 26
ca. 185
ø 12,5
WEVDK-- 43-- D--6
AB
PT
b
a
PG 9
ø45
Solenoid a
4/3 function valve
Solenoid b
4/2 valve with detents
1,3
49
ca. 9465,426
ca. 185
Manual override on each solenoid
ca. 94 65,4
ca. 253,5
ca. 94
PG 9
11,4 40,4
31
ISO 4401 siz e 3 interface
ca. 57
clearance to
remove coil
46
40 / 40
237
46
84 13
clearance to
remove plug
M5
Mounting screw
M5 x 45, DIN 912
Tightening torque
Ma = 4 ... 6 Nm
Nameplate
Solenoid b
6. Schematic section
Seal kit no. DS-- 067, comprising:
Itm.
Qty. Qty. Description Size
1 4 2 O--ring no. 019 ∅ 20,35 x 1,78 N70
2 2 1 O--ring no. 016 ∅ 15,60 x 1,78 N90
3 2 2 O--ring no. 018 ∅ 18,77 x 1,78 N70
4 4 4 O--ring no. 012 ∅ 9,25 x 1,78 N90
5 -- 1 Copper ring
∅ 8,00/5,50x1,00
DIN7603A
6 2 2 O--ring ∅ 2,0 x 1,5V
7 2 2 O--ring ∅ 6,0 x 1,5V
8 2 2 Backup ring ∅ 5,3x1,2x0,8 FI0751
4/2 valves (1 solenoid)
4/2 valves with detents (2 solenoids)
4/3 valves (2 solenoids)
12 435
6,7,8
400--P--181410--EN--Ad/09.15
4/ 4
7. Model code key
Electrically actuated directional valve
42
43
A
B
AD, AG, AH, AJ
6
(Blank) = Nitrile seals (standard)
V
1 ... 9
=
=
=
=
=
=
=
=
direct acting and 2-- stage
4/2 function
4/3 function
4/2 function, solenoid at a end
4/2 function with 4/3 spool, solenoid at A end
ISO 4401 size 3 interface
Viton -- seals
design number (omit when ordering)
WE
K
43
-- --
G
--
6
--
_
--
1
4/2 function, solenoid at b end
=
BD, BG, BH, BJ 4/2 function with 4/3 spool, solenoid at B end=
D, G, H, J 4/3 function, solenoids at both ends=
Voltages and current plainly specified
Ex.
VD
=
=
standard --model per current data sheet
special features by arrangement
For special seals -- contact
A ... Q
Z ... R
VD
24 V DC
C = 4/2 function with detents at spool end positions, solenoids at both ends
BUCHER
8. Related data sheets
Old no. New no.
i--00 400--P -- 010101-- E Table of interface equivalents
i--31 400--P -- 030501-- E DIN 24 340 size A6 interface
P--20 400--P --515101 --E LRS Power Reducing DIN plug
W-- 01 400 --P -- 102100-- E High Performance Spool Valves /Principles/Overview
E 2015 by Bucher Hydraulics AG Frutigen, CH-3714 Frutigen
www.bucherhydraulics.cominfo.ch@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.
