Data Sheet

Bulletin 71.4:SR8
8
Table 5. C
v
Coefcients (continued)
SPRING RANGE,
PSIG (bar)
SET
PRESSURE,
PSIG (bar)
C
V
AT % BUILD-UP
Elastomer Diaphragm Metal Diaphragm
NPS 1-1/2 (DN 40)  NPS 1-1/2 (DN 40)
10% 20% 30% 40% 10% 20% 30% 40%
2 to 8
(0,14 to 0,55)
2 (0,14) 1.95 2.54 2.81 3.31
Not Available5 (0,34) 1.55 2.73 4.87 6.66
8 (0,55) 1.47 3.05 6.32 8.91
5 to 25
(0,34 to 1,7)
5 (0,34) 1.37 1.64 2.54 2.94 1.37 1.51 1.81 2.06
15 (1,0) 1.87 4.12 7.34 8.17 1.31 1.68 2.40 3.08
25 (1,7) 2.16 5.32 9.55 10.50 1.35 1.81 2.71 3.57
15 to 70
(1,0 to 4,8)
15 (1,0) 1.87 2.94 4.14 5.83 1.37 1.62 2.16 2.79
30 (2,1) 4.83 7.28 7.83 8.70 1.66 2.59 3.66 4.76
45 (3,1) 6.25 9.33 9.54 10.01 1.81 3.05 4.36 5.66
50 (3,4) 6.57 9.79 9.92 10.30 1.84 3.16 4.52 5.86
60 (4,1) 7.09 10.52 10.52 10.76 1.89 3.32 4.77 6.18
70 (4,8) 7.48 10.90 10.90 10.90 1.93 3.44 4.95 6.42
25 to 90
(1,7 to 6,2)
35 (2,4) 1.85 3.13 4.40 5.66 1.07 1.41 1.75 2.25
50 (3,4) 3.61 6.48 7.44 8.17 1.46 2.29 3.11 4.05
75 (5,2) 5.20 9.49 10.15 10.39 1.82 3.08 4.31 5.65
90 (6,2) 5.79 10.59 10.90 10.90 1.96 3.37 4.75 6.22
35 to 100
(2,4 to 6,9)
35 (2,4) 2.93 3.99 5.59 8.06 1.47 2.00 2.59 3.28
50 (3,4) 4.13 6.41 7.91 9.36 1.64 2.47 3.57 4.75
75 (5,2) 5.22 8.60 9.97 10.51 1.80 2.90 4.45 6.04
100 (6,9) 5.83 9.80 10.90 10.90 1.88 3.13 4.93 6.75
75 to 125
(5,2 to 8,6)
75 (5,2) 5.85 9.55 10.56 10.51 3.62 5.21 6.22 6.38
100 (6,9) 6.05 10.50 10.74 10.41 3.89 5.08 6.70 7.87
125 (8,6) 7.46 10.68 10.81 3.96 5.52 7.34
Shaded areas indicate conditions where maximum differential pressure for the spring range is exceeded.
SPRING RANGE,
PSIG (bar)
SET
PRESSURE,
PSIG (bar)
C
V
AT % BUILD-UP
Elastomer Diaphragm Metal Diaphragm
NPS 2 (DN 50)  NPS 2 (DN 50)
10% 20% 30% 40% 10% 20% 30% 40%
10 to 25
(0,69 to 1,7)
10 (0,69) 9.54 12.90 20.16 25.94 6.97 9.73 12.00 14.51
15 (1,0) 13.77 25.30 30.19 30.19 9.10 11.66 14.20 17.37
25 (1,7) 19.87 30.19 30.19 30.19 9.39 12.66 16.48 19.66
15 to 50
(1,0 to 3,4)
15 (1,0) 12.16 17.45 24.11 28.98 6.97 9.67 11.54 12.29
25 (1,7) 14.20 24.03 29.03 30.08 8.32 11.20 14.90 17.73
50 (3,4) 22.24 28.76 29.98 29.90 9.57 15.28 20.12 23.86
25 to 60
(1,7 to 4,1)
25 (1,7) 12.93 21.88 30.01 30.19 8.26 11.29 15.06 18.15
50 (3,4) 18.16 29.95 30.19 30.19 9.12 14.28 19.11 22.97
60 (4,1) 22.06 30.19 30.19 10.75 17.53 22.96
Shaded areas indicate conditions where maximum differential pressure for the spring range is exceeded.
Table 5. C
v
Coefcients (continued)
Table 5. C
v
Coefcients (continued)
SPRING
RANGE,
PSIG (bar)
SET
PRESSURE,
PSIG (bar)
C
V
AT % BUILD-UP
Elastomer Diaphragm Metal Diaphragm
NPS 3 (DN 80) NPS 3 (DN 80)
10% 20% 30% 40% 10% 20% 30% 40%
10 to 25
(0,69 to 1,7)
10 (0,69) 12.81 17.24 24.09 28.28 8.76 14.51 19.01 22.35
15 (1,0) 13.42 21.30 28.37 35.03 11.58 17.34 21.63 25.08
25 (1,7) 17.78 28.44 37.90 39.21 13.03 19.27 23.95 28.24
15 to 50
(1,0 to 3,4)
15 (1,0) 10.11 15.34 22.43 28.58 11.25 16.30 20.36 23.58
25 (1,7) 12.15 23.16 33.49 39.21 10.85 18.05 22.17 26.93
50 (3,4) 12.51 26.03 38.44 39.08 14.70 23.64 28.97 33.40
25 to 60
(1,7 to 4,1)
25 (1,7) 11.29 20.42 28.43 35.61 10.73 17.26 22.36 26.33
50 (3,4) 13.31 25.82 37.56 39.11 13.57 21.54 27.47 31.76
60 (4,1) 24.47 34.81 39.21 15.57 23.99 30.03
Shaded areas indicate conditions where maximum differential pressure for the spring range is exceeded.