Relief Valve Discharge Rates

2
1
1
⁄4" 009M2QT
Rate of Flow
Pressure
1
1
⁄2" 009M2QT
Rate of Flow
Pressure
2" 009M2QT
Rate of Flow
Pressure
2
1
⁄2", 3" 009
lpm gpm
1330 350
1140 300
950 250
760 200
570 150
380 100
190 50
0 0
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 psi
0 .7 1.4 2.1 2.8 3.5 4.1 4.8 5.5 6.2 6.9 7.6 8. 3 9.0 9.6 10.3 11.0 11.7 12.4 bar
Rate of Flow
Pressure
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 psi
0 .7 1.4 2.1 2.8 3.5 4.1 4.8 5.5 6.2 6.9 7.6 8.3 9.0 9.7 10.3 11.0 11.7 12.4 bar
lpm gpm
532 140
456 120
380 100
304 80
228 60
152 40
76 20
0 0
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 psi
0 .7 1.4 2.1 2.8 3.5 4.1 4.8 5.5 6.2 6.9 7.6 8.3 9.0 9.7 10.3 11.0 11.7 12.4 bar
lpm gpm
513 35
456 120
399 105
342 90
285 75
228 60
171 45
114 30
57 15
0 0
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 psi
0 .7 1.4 2.1 2.8 3.5 4.1 4.8 5.5 6.2 6.9 7.6 8.3 9.0 9.7 10.3 11.0 11.7 bar
lpm gpm
836 220
760 200
684 180
608 160
532 140
456 120
380 100
304 80
228 60
152 40
76 20
0 0
Note: These curves
represent catastrophic
or worst case discharge
rates. These curves
were developed by pres-
surizing the outlet of
the backflow preventer
with the second check
valve’s internals removed
from the body.