12/12/16 73
POCLAIN HYDRAULICS Hydraulic components - Directional control valves
Mechanically operatedElectrically operated Hydraulically operated
4/2, 4/3 WAY DIRECTIONAL VALVES KV (NG 6, 10)
• NG 6, 10
• Up to 350 bar [5 076 PSI]
• Up to 60 L/min [15.8 GPM] for N
G 6
• Up to 100 L/min [26.4 GPM] for N
G 10
• Connecting dimensions to ISO 4401.
KV-4/3-5KO-6-R, KV-4/3-5KO-10-R
Operation Hydraulic symbols
Directional valves type KV with direct mechanical operation by means of a lever control the
direction of the hydraulic fluid medium flow.
These directional valves consist of a housing (
1), control spool (2), control mechanism (3),
and return spring (4). In 4/3-way directional valves the centre position of the control spool
is the neutral position. The change-over to one of the operating positions "a" or "b" is done
by moving the operating pin lever (5) in such a manner that its acts on the control spool (2)
so as to clear corresponding flow ways and establish relevant links between ports, A, B, P,
and T.
On ceasing to apply force to the control mechanism (3), the return spring (4) push the
contro
l spool into the neutral position.
There are two types of operation:
1/ With control spool not held in the operating position (the control spool returns to neutral
position on ceasing to apply force to the control mechanism - type KV-../..-R).
2/ With control spool held (detent) in the operat
ing position (the control spool remains in
the operating position on ceasing to apply force to the control mechanism lever - type
KV-../..-RA).
Spool types
Features
Size 610
Flow rate L/min [GPM] 60 [15.8] 100 [26.4]
Operating pressure
P, A , B b a r [PSI] 350 [5 076]
Tbar [PSI] 160 [2 320]
Viscosity range mm
2
/s [SUS]
15 to 380 [69.5 to
1 760]
Oil temperature range °C [°
F]
-20 to+70 [-4 to 158]
Filtration NAS 1638
8
Mass kg [lb]
2,05 [
4.52] 5,23 [11.53]
Mounting position
Optional
Dimensions
3. Control mechanism on side ’’a’’
4/3 valves
4/2 valves, spool types 51A
6. Fixing screws 4 pcs M5x30 to ISO 4762-10.9
(by special order).
Required tightening torque Md = 9 Nm.
7. O-ring 9.25x1.78
8. Valve cap.
9. Nameplate.
3. Control mechanism on side ’’a’’
4/3 valves
4/2 valves, spool types 51A
6. Fixing screws 4 pcs M6x60 to ISO 4762-10.9
(by special order).
Required tightening torque Md = 15 Nm.
7. O-ring 12.42x1.78
8. Valve cap.
9. Nameplate.
Required quality of the
mating surface.
Size 6 Size 10
74 12/12/16
Directional control valves - Hydraulic components POCLAIN HYDRAULICS
Cartridge throttle
If flow rates greater than permissible occur during change-over, a cartridge
throttle must be fitted into P-line of the directional valve.
'P-Q Performance curves
Flow
Diff. pressure
Measured at 50°C [122°F] and viscosity of 32 mm
2
/s [148 SUS].
Size 6
Size 10
Throttle
Spool
P-A P-B A-T B-T P-T
1
b,D b,D c,B c,C -
2
c,B c,B c,A c,A d,G
6
b,E b,E a,B a,B -
51A
c,D b,D c,C a,B -
Flow
Flow
Diff. pressure
Diff. pressure
12/12/16 75
POCLAIN HYDRAULICS Hydraulic components - Directional control valves
Mechanically operatedElectrically operated Hydraulically operated
Model code
4K
Control spool held
R
RA
Number of spool position
2
2
3
3
5/-
Seal type
No designation
NBR seals for mineral oil HL,HLP
to DIN 51524
E
FPM seals for HETG, HEES, HEPG
to VDMA 24568 and ISO 15380
Special requirements to be
briefly specified
-V K O
Throttle mm [in]
No designation
Without throttle in P line
D08
Throttle Ø 0,8 [0.03 dia.]
D10
Throttle Ø 1,0 [0.04 dia.]
D12
Throttle Ø 1,2 [0.05 dia.]
----
Size
Size 6
6
Size 10
10
Spool type
1
2
6
51A
-
*
-
76 12/12/16
Directional control valves - Hydraulic components POCLAIN HYDRAULICS
