
Water velocity c and friction resistances
∆
h
STERLING
in straight pipelines per 100 m pipe length
Berkefeld
Flow rate
Inside pipe diameter d (mm)
Q
20
25
32
40
50
70
80
100
125
150
175
200
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
c
∆
h
(m³/h)
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
m/s
m
0.4
0.35
1.31
0.23
0.44
0.14
0.18
0.6
0.53
2.79
0.34
0.92
0.21
0.27
0.8
0.71
4.75
0.45
1.55
0.28
0.46
1.0
0.89
7.19
0.57
2.36
0.35
0.69
0.22
0.23
1.2
1.06
10.1
0.68
3.29
0.42
0.96
0.27
0.32
1.4
1.24 13.53
0.79
4.36
0.48
1.27
0.31
0.43
1.6
1.42 17.41
0.91
5.56
0.55
1.65
0.35
0.54
1.8
1.59 21.75
1.02
6.95
0.62
2.49
0.40
0.67
2.0
1.78 26.35
1.13
8.45
0.69
2.04
0.44
0.79
0.28
0.27
2.5
1.41 12.84
0.87
3.76
0.55
1.21
0.35
0.41
3
1.70 18.27
1.04
5.27
0.66
1.72
0.43
0.57
3.5
1.98 24.20
1.22
7.11
0.78
2.28
0.50
0.75
4
1.38
9.05
0.89
2.91
0.57
0.96
0.33
0.25
4.5
1.56 11.25
1.00
3.64
0.64
1.20
0.38
0.31
5
1.73 13.78
1.11
4.43
0.71
1.45
0.42
0.38
5.5
1.90 16.53
1.22
5.35
0.78
1.75
0.46
0.46
6
2.08 19.50
1.33
6.29
0.85
2.03
0.50
0.54
7
2.42 26.60
1.55
8.40
0.99
2.72
0.59
0.73
0.39
0.26
8
1.77 10.85
1.13
3.50
0.67
0.94
0.44
0.33
0.28
0.11
9
1.99 13.63
1.27
4.36
0.75
1.13
0.50
0.42
0.32
0.14
10
2.21 26.70
1.42
5.25
0.84
1.43
0.55
0.51
0.35
0.17
12
2.66 23.65
1.70
7.63
1.00
2.01
0.67
0.71
0.43
0.24
14
1.98 10.21
1.17
2.70
0.78
0.95
0.50
0.31
0.32
0.10
16
2.27 13.07
1.34
3.48
0.89
1.23
0.57
0.40
0.36
0.13
18
2.55 16.62
1.51
4.37
1.00
1.53
0.64
0.50
0.41
0.17
20
2.83 20.40
1.67
5.33
1.11
1.86
0.71
0.61
0.45
0.20
22
3.12 24.20
1.84
6.42
1.22
2.24
0.78
0.73
0.50
0.24
24
2.00
7.56
1.33
2.65
0.85
0.86
0.54
0.28
0.38
0.11
26
2.18
8.82
1.44
3.07
0.92
1.00
0.59
0.33
0.41
0.13
28
2.35 10.17
1.55
3.53
0.99
1.14
0.63
0.37
0.44
0.15
30
2.51 11.58
1.66
4.03
1.06
1.30
0.68
0.43
0.47
0.17
35
2.93 15.66
1.94
5.42
1.24
1.73
0.79
0.57
0.55
0.23
0.40
0.11
40
3.35 20.28
2.22
7.03
1.42
2.24
0.91
0.73
0.63
0.29
0.46
0.14
45
3.77 25.38
2.49
8.78
1.59
2.80
1.00
0.91
0.71
0.37
0.52
0.17
50
2.77 10.81
1.77
3.44
1.13
1.11
0.79
0.45
0.58
0.21
0.44
0.11
55
3.05 12.95
1.95
4.13
1.25
1.33
0.87
0.53
0.64
0.25
0.49
0.13
60
3.32 15.38
2.13
4.90
1.36
1.57
0.94
0.63
0.69
0.29
0.53
0.15
65
3.60 18.00
2.30
5.70
1.47
1.83
1.02
0.74
0.75
0.34
0.58
0.18
70
3.88 20.78
2.48
6.55
1.59
2.10
1.10
0.84
0.81
0.39
0.62
0.20
75
4.15 23.72
2.65
7.50
1.70
2.39
1.18
0.96
0.87
0.44
0.66
0.23
80
4.43 26.93
2.83
8.50
1.81
2.71
1.26
1.09
0.92
0.50
0.71
0.26
85
3.01
9.60
1.93
3.10
1.34
1.22
0.98
0.56
0.75
0.29
90
3.19 10.70
2.04
3.40
1.42
1.36
1.04
0.62
0.80
0.32
95
3.36 11.80
2.15
3.76
1.49
1.50
1.10
0.69
0.84
0.36
100
3.54 13.10
2.27
4.15
1.57
1.66
1.15
0.76
0.89
0.39
110
3.89 15.80
2.49
5.00
1.73
1.99
1.27
0.91
0.97
0.47
120
4.25 18.75
2.72
5.90
1.89
2.36
1.39
1.08
1.06
0.55
130
4.60 21.90
2.95
6.90
2.05
2.74
1.50
1.25
1.15
0.64
140
3.17
7.96
2.20
3.16
1.62
1.44
1.24
0.74
160
3.62 10.33
2.52
4.10
1.85
1.87
1.42
0.96
180
4.08 13.05
2.83
5.15
2.08
2.34
1.59
1.20
200
4.53 16.03
3.15
6.32
2.31
2.87
1.77
1.47
The pressure head losses
∆
h apply to medium-rough pipes (k=00.1 mm). With new, smooth pipes (k=0.05 mm) they
have to be multiplied by 0.9; with very rough pipes (k=0.5 mm) which have been in operation for a longer time with 1.4.
Berkefeld-Filter Anlagenbau GmbH, Lückenweg 5, D-29227 Celle, Phone: (0 51 41) 803-0, Fax: 803-100