February 1996 GB-2321A
X(C)G2V-6/8, 10 Series
Typical Section
X(C)G2V-***-1* valve
Basic Characteristics
Max. inlet pressure 350 bar . . . . . . . . . .
(5000 psi)
Max. reduced pressure 330 bar. . . . . . .
(4780 psi)
Maximum flow 300 L/min (80 USgpm). .
Mounting face to ISO 5781
(B port high pressure inlet):
X(C)G2V-6 AG-06-2-A. . . . . . . . . . . . . . .
X(C)G2V-8 AH-08-2-A. . . . . . . . . . . . . . .
General Description
Where sections of an hydraulic system
are required to operate at a pressure
below that of the general system, it is
frequently more convenient to use a
pressure reducing valve than to add
further pump sections.
These two-stage pressure reducing
valves allow full flow from inlet to outlet
port until the reduced pressure setting is
reached, whereupon the outlet flow is
closed off. Reduced pressure setting is
manually adjustable at the pilot stage.
Five ranges of reduced pressure
adjustment are available.
High valve response ensures that the
reduced outlet pressure is unaffected by
inlet pressure peaks. Excessive build-up
of outlet port pressure (e.g. caused by
flow back from an actuator) is prevented
by the small check in the main-stage
which connects the outlet port to the
pilot stage.
For applications where full reverse flow
is required an optional integral check
valve is available (model types XCG).
Models with electrohydraulic
proportional control, types KX(C)GV, are
described in catalog 2322.
Features and Benefits
F Close matching to machine
requirements with choice of five
adjustment ranges of reduced
pressure.
F Excellent repeatability and stable
performance results from cartridge
design of main-stage parts.
F Minimal pump flow losses when using
several valves in parallel, results from
design of internal pilot system.
F Free reverse flow from integral check
valve option.
F International mounting surfaces.
F Low installed cost and space
requirement from high power/size
ratios (more than double that of many
conventional designs).
Pressure Reducing Valves
Vickers
®
Pressure Relief
XCG2V model (integral check valve for
free flow A to B)
BAY
BAY
(F3-)
Fluid compatibility
Blank = Anti-wear hydraulic oil
(class L-HM), invert emulsion
(class L-HFB) or water glycol
(class L-HFC)
F3 = As above or phosphate
ester (class L-HFD)
Integral check valve (free reverse
flow)
C = Integral check valve
Omit if not required
Mounting surface, ISO 5781
With B port, high pressure inlet and A
port, reduced pressure outlet
6 = Size 06
8 = Size 08
X(C)G2V- * * * -1*
1 2 3 4 5 6
1
2
3
Reduced pressure adjustment
control range
A = 2 to 35 bar (30 to 500 psi)
B = 5 to 70 bar (44 to 1000 psi)
C = 5 to 140 bar (44 to 2000 psi)
F = 5 to 210 bar (44 to 3000 psi)
G = 5 to 330 bar (44 to 4780 psi)
Type of manual adjustment
K = Micrometer with keylock
M = Micrometer without keylock
W = Screw/locknut
Design number, 1* series
Subject to change. Installation
dimensions unaltered for design
numbers 10-19 inclusive.
4
5
6
2
Functional Symbols
XG2V model (no reverse flow check)
Model Code
For valves with manual adjustment only
Operating Data
Data is typical with oil at 22 cSt (106 SUS) and at 50_C (122_F).
Maximum pressures:
Port B (pressure inlet)
Port A (reduced pressure outlet)
Port YJ
350 bar (5000 psi)
See model code position
2 bar (30 psi)
4
Rated flow rates at ∆p = 12 bar (175 psi):
X(C)G2V-6
X(C)G2V-8
200 L/min (53 USgpm)
300 L/min (80 USgpm)
Pressure adjustment ranges
See model code position
4
Minimum pressure differential (P
B
- P
A
)
for effective reduced pressure control,
all models
20 bar (300 psi) approx.
Pilot control drain flow, all models
at P
B
100 bar (1450 psi)
at P
B
300 bar (4350 psi)
1,0 L/min (0.26 USgpm)
1,3 L/min (0.34 USgpm)
Hydraulic fluids and fluid temperatures See page 3
Temperature limits See page 3
Mass See page 6
Spare parts/service information 40630
J Back pressure at this port is additive to the reduced pressure setting of the valve.
Pressure Drop
0
50
100
150
200
250
300
bar
0
1000
2000
3000
4000
psi
0
0
100 200 300
20 40 60 80
L/min
USgpm
Reduced pressure
Flow rate
50 150 250
0
2
4
8
10
12
bar
6
0
25
50
75
100
125
150
175
psi
50 100 150 200 250 300 L/min
0 20 40 60 80USgpm
Pressure drop
Flow rate
A
B
CD
10 30 50 70
1
3
Pressure Underride
X(C)G2V-8 examples
From port B to A at pressures below
reduced pressure setting:
X(C)G2V-6 Curve A. . . . . . . . . . . . . . . . .
X(C)G2V-8 Curve B. . . . . . . . . . . . . . . . .
From port A to B through check valve
(main stage assumed closed), XCG2V
models only:
XCG2V-6 Curve C. . . . . . . . . . . . . . . . . . .
XCG2V-8 Curve D. . . . . . . . . . . . . . . . . . .
Hydraulic Fluids
All valves can be used with:
Anti-wear hydraulic oils (class L-HM)
Invert emulsions (class L-HFB)
Water glycol (class L-HFC)
Phosphate ester (class L-HFD), adding
“F3-” prefix at model code .
The extreme viscosity range is from 500
to 13 cSt (2270 to 70 SUS) but the
recommended range is 54 to 13 cSt
(245 to 70 SUS).
For further information about fluids see
catalog 694.
Temperature Limits
Ambient:
Min. –20_C (–4_F). . . . . . . . . . . . . . . . . .
Max. 70_C (158_F). . . . . . . . . . . . . . . . . .
Fluid temperature:
Min. –20_C (–4_F). . . . . . . . . . . . . . . . . .
Max.* 70_C (158_F). . . . . . . . . . . . . . . . .
*
To obtain optimum service life from both
fluid and hydraulic system, 65_C (150_F)
normally is the maximum temperature
except for water-containing fluids.
For synthetic fluids consult fluid
manufacturer or Vickers representative
where limits are outside those of
petroleum oil.
Whatever the actual temperature range,
ensure that viscosities stay within the
limits specified in the “Hydraulic Fluids”
section.
Contamination Control Requirements
Recommendations on contamination
control methods and the selection of
products to control fluid condition are
included in Vickers publication 561,
“Vickers Guide to Systemic Contamination
Control”. The book also includes
information on the Vickers concept of
“ProActive Maintenance”. The following
recommendations are based on ISO
cleanliness levels at 2 mm, 5 mm and 15
mm. For products in this catalog the
recommended levels are:
Up to 210 bar (3050 psi) 19/17/14. . . . .
Above 210 bar (3050 psi) 19/17/14. . . .
Installation Dimensions in mm (inches)
3rd angle
projection
61,0 (2.4)
C D
45,0 (1.8) for removal of
protective cap
176,0 (6.9)
H
E
4 holes Ø11,0 (0.43 dia)
spotfaced to Ø17,0 (0.68 dia)
7,5 (0.29) A/F
Turn clockwise to increase
reduced pressure setting
17,0 (0.67)
A/F
98,0
(3.8)
30,0 (1.2)
16,0 (0.63)
G
1
/
4
I (
1
/
4
I BSPF)
reduced pressure
gage port
Port B, high
pressure inlet
Port A, reduced
pressure outlet
120,0 (4.7)
196,0 (7.7) fully out
25,0
(1.0)
18,0 (0.7) for key removal
Type K only:
F
Micrometer Adjustment Options:
“K” or “M” in Model Code
“K” Feature
To adjust pressure setting, insert key
and turn clockwise. Turn micrometer
knob clockwise to increase pressure
setting; counter-clockwise to decrease
setting.
When the key is removed, the knob can
spin freely without affecting the pressure
setting.
5
4
Model
C D E F H
X(C)G2V-6 42,0
(1.7)
66,0
(2.6)
10,0
(0.4)
89,0
(3.5)
92,0
(3.65)
X(C)G2V-8 40,0
(1.6)
77,0
(3.1)
11,0
(0.43)
104,0
(4.1)
107,0
(4.25)
21,0 (0.83)
XCGVM-6-10R Subplate
Port Y (see “Functional Symbols” for usage)
Port A (reduced
pressure outlet)
Port B (high
pressure inlet)
Valve locating pin
(Not used; recess for O-seal only.
Port X location)
Port Y (see “Functional Symbols” for usage)
Port A (reduced
pressure outlet)
Port B (high
pressure
inlet)
Valve locating pin
(Not used; recess for O-seal only.
Port X location)
116,0 (4.5)
104,0 (4.1)
80,0 (3.15)
12,0 (0.5)
26,9 (1.06)
43,0 (1.7)
20,0 (0.8)
150,0
(6.0)
88,0
(3.5)
24,0
(0.95)
69,0
(2.7)
126,0
(5.0)
18,9
(0.75)
Port A u
Port B u
Tapped G1 (1I
BSPF) x 19,0 (0.75)
depth full thread, in
underside
R28,0
(1.1 rad.)
Ø 7,5 (0.3 dia) x 6,0
(0.24) deep for valve lo-
cating pin
4 holes, Ø 11,0 (0.43
dia) through, Ø 17,5
(0.69 dia) spotface
Port Y u
Port X u
Tapped G
1
/
4
(
1
/
4
I BSPF) x
12,0 (0.5)
depth full
thread, in un-
derside
Y
X
A
B
4 holes tapped
M10 x 16,0 (0.63)
min.
depth full thread
56,0
(2.2)
Y See “Mounting Surfaces” section on next page for port usage.
5
Views on Bottom Face of Valves (See also “Mounting Surfaces”, page 6. All O-seals supplied).
X(C)G2V-6 X(C)G2V-8
D (min.)
F (min.)
Q (min.)
N (min.)
EY
J
Y
PY
H
K
L
M
T
S
R
U
(min.)
Ø M10 x 16,0 (0.63)
min. depth full thread
Ø 4,8 (0.19 dia)
Ø 7,5 (0.3 dia) x
6,0 (0.24) deep min.
A
B
X
Y
Ø 4,8 (0.19 dia)
C
(min.)
Y Tolerance on bolt and pin locations
"0,1 mm (0.004I).
6
Mounting Surfaces, Based on
ISO 5781 Codes:
AG-06-2-A
AH-08-2-A
When a subplate is not used a raised
machined pad must be provided for
mounting. The pad must be flat within
0,01mm/100 mm (0.001I/10I) and
smooth within 0,8 mm (32 min).
Dimensional tolerances are "0,2 mm
(0.008I) except where indicated.
Port functions
A = Reduced pressure outlet (also free
reverse flow inlet for XCG2V
valves)
B = High pressure inlet (also free
reverse flow outlet for XCG2V
valves)
X = Not used for X(C)G2V valves; can
be omitted or plugged
Y = Drain port
Size
A dia. B dia. C D E F H J K
06 14,7
(0.58)
14,7
(0.58)
61,0
(2.4)
9,0
(0.4)
42,9
(1.69)
9,0
(0.4)
35,7
(1.4)
31,8
(1.25)
21,4
(0.84)
08 23,4
(0.92)
23,4
(0.92)
78,0
(3.1)
8,8
(0.35)
60,3
(2.37)
8,8
(0.35)
49,2
(1.94)
44,5
(1.75)
39,7
(1.56)
Size L M N P Q R S T U
06 21,4
(0.84)
7,1
(0.28)
10,0
(0.4)
66,7
(2.62)
10,0
(0.4)
58,7
(2.3)
33,3
(1.3)
7,9
(0.31)
87,0
(3.4)
08 20,6
(0.81)
11,1
(0.44)
10,8
(0.43)
79,4
(3.125)
10,8
(0.43)
73,0
(2.87)
39,7
(1.56)
6,4
(0.25)
101,0
(4.0)
Installation Data
Mounting attitude unrestricted
Subplates
For X(C)G2V-6 valves see type
XCGVM-6-10R, on page 5.
For X(C)G2V-8 valves consult your
Vickers representative.
Mounting Bolts/Torques
For all models, bolt kit BKXG2V-6.
Bolts should be torqued to 59-73 Nm
(44-53 lbf ft), with threads lubricated.
Mass
X(C)G2V-6 valves 4,8 kg (10.6 lb). . . . .
X(C)G2V-8 valves 5,6 kg (12.4 lb). . . . .
Ordering Procedure
All valves, subplates, bolt kits should be
ordered by full model code designation.
