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VA33 Series Ordering Information and Dimensions
VA33A-
VA33B-
1/4 in. Female NPT
1/4 in. Male NPT
1/4 in. ISO Male Tappered
1/2 in. Male NPT
1/2 in. ISO Male Tappered
0.35
75.7
41.1
41.1
65.0
65.0
2.98
1.62
1.62
2.56
2.56
3/4
9/16
9/16
7/8
7/8
1.2
F-4N-
M-4N-
M-4R-
M-8N-
M-8R-
End Connections
Cv
Basic Ordering Number
mm inch
Hex
L
VDA33 Series Ordering Information and Dimensions
VDA33
1/4 in. DK-LOK
1/4 in. Male NPT 1/4 in. DK-LOK
6mm DK-LOK
8mm DK-LOK
0.37
82.0(3.23)
82.0(3.23)
84.3(3.32)
79.2(3.12)
9/16 in.
9/16 in.
14mm
16mm
5/8 in.
D-4T-S
D-6M-S
D-8M-S
MD-4N4T-S
End Connections
Cv
Basic Ordering Number
L
Inlet
Outlet
H
h
Dimensions mm(inch)
psig
3 to 50
50 to 150
150 to 350
350 to 600
Bar
0.2 to 3.4
3.4 to 10.3
10.3 to 24.1
24.1 to 41.3
Designator
3
50
150
350
Table 3.
VA33 & VDA33 Series
Spring Cracking Pressure Range Designator
Cracking Pressure Range
@21 C (70 F)
How to adjust cracking pressure
Step 1
Step 2
Step 3
INLET
INLET
INLET
Adjustable screw
Locking screw
Sllghtly unscrew the locking screw
counter-clockwise.
Locking screw
Allen key
OUTLET
OUTLET
1. Move out the allen key up to the locking screw position.
2. To lock out the locking screw, turn the allen key clockwise.
Adjustable screw
Locking screw
OUTLET
1. Gently slide the allen key up to adjustable screw position.
2. Adjust cracking pressure.
To increase cracking pressure, turn adjustable screw clockwise.
To decrease cracking pressure, turn adjustable screw counter-clockwise.
Cracking Pressure vs. Reseal pressure
VA33 and VDA33 Series valves set to crack at 20 psig(1.3 bar) or lower may require
back pressure(downstream pressure) to reseal the valve bubble tight.
Example shown : For a valve set to crack at 31 bar (450 psig), the minimum reseal
pressure would be 27 bar (390psig).
5
Check Valves