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Valves
DPL417
877.963.4966 •
dixonvalve.comI
Safety Check Valves for Pneumatic Applications
Safety Check Valves
Application:
•
used in temporary plant/factory air lines, construction sites, shipyards or utilities
•
not for use in applications where 100% of the available air is required, i.e. sand blast,
pile driving rigs,expansion joint blow down pipes, etc.
Features:
•
high flow valve provides optimum performance
•
controls excess air flow (SCFM) in only one direction
•
automatically senses change in air flow and shuts off the flow in the event of a surge in
excess of valve flow rating thus preventing hose whip
•
solid brass body and valve
•
stainless steel spring and roll pin
•
maximum operating pressure:
350 PSI
•
maximum temperature:
250°F (121°C)
•
does not prevent backflow
Specification:
•
conforms to OSHA regulation 1926.302 (b) (7) requiring a safety device at the source of the
air supply and at branch air lines
How It Works:
•
Safety check valves utilize the pressure differential across the valve to operate the valve and
spring assembly. The pressure differential is directly related to the flow of air (SCFM) through
the valve.
•
When the pressure differential is within the operating limits - below the cutoff flow - of the
unit, the force on the valve exerted by the spring is greater than that caused by the pressure
differential (see "Open Position" graphic above). The valve remains open and normal
operation continues.
•
When the pressure differential is above the cutoff limit, the force on the valve exerted by the
pressure differential is greater than the force exerted by the spring, and the valve closes (see
the "Closed Position" graphic above).
•
After the repair is made, normal operation is automatically enabled when pressure across the
valve equalizes through the bleeder hole.
•
The valve spring size can be specified by determining the air flow during normal operation
and by estimating the air flow if a failure or rupture occurs.
NPT &
Hose
ID Size
Cut-off Flow Rate
(SCFM at 90 PSI)
Brass
NPT &
Hose
ID Size
Cut-off Flow Rate
(SCFM at 90 PSI)
Brass
Part # Price/E
Part # Price/E
¼"
23-29
SCVL2
$65.08
1¼"
260-290
SCVL10
$242.37
⅜"
30-36
SCVL3
61.05
300-340
SCVM10
242.37
39-47
SCVM3
61.05
440-500
SCVS10
242.37
52-65
SCVS3
61.05
570-630
SCVH10
242.37
½"
70-78
SCVM4
65.55
1½"
300-360
SCVL12
406.54
80-96
SCVS4
65.55
470-530
SCVM12
406.54
¾"
72-88
SCVL6
103.75
564-602
SCVX12
406.54
92-108
SCVM6
103.75
640-720
SCVS12
406.54
112-128
SCVR6
103.75
750-830
SCVH12
406.54
132-148
SCVJ6
103.75
2"
510-590
SCVL16
555.14
160-180
SCVS6
103.75
725-825
SCVM16
555.14
180-200
SCVH6
103.75
900-1050
SCVS16
555.14
1"
165-195
SCVL8
117.33
1100-1200
SCVH16
555.14
220-260
SCVM8
117.33
3"
1200-1400
SCVL24
2357.34
280-320
SCVS8
117.33
2400-2700
SCVS24
2357.34
310-340
SCVH8
117.33
2850-3050
SCVH24
2357.34
Flow
Direction
Closed Position
Open Position