Calculation as per water supply Manual of CPHEEO
Pipe Line
CLAUSE 6.17.2 Computation of Hammer Pressure
C*V0
Hmax= g
Where
Hmax= Maximum pressure rise in the closed conduit above normal pressure in m
C= Velocity of pressure wave travel in m/s
g= Acceleration due to gravity in m/s2
V0 = Normal velocity in the pipeline before sudden closure in m/s
C can be determined by
1425
C=
(1+kd/ECt)^0.5
Pipe Material Steel
k Bulk modulus of water 207000000 kg/m2
d Diameter of pipe in m 813 mm 0.813 m
Ct Pipe wall thickness 5.8 mm 0.0058 m
E Modulus of elasticity of pipe material in kg/m2 2.1E+10 Steel
kd 168291000
Ect 121800000
C 923.36069
Demand 225.99 MLD Pumping Hours 23 Hrs
Area of Pipe 0.5191238
V0 0.0027293 m3/s 0.005258 m/s
g 9.81 m/s
Hmax 0.494869 m
0.6572006 Check OK
Pressure at 125
times of Vo
Hence No Serge Device Required
Second Check as per clause 6.17.3(a) of Manual
If the sum of the maximum operating pressure or the maximum pipeline static pressure
which ever is higher and the calculated surge pressure does not exceed 1.1 times the internal
design pressure, no allowance for surge pressure is required
Designed internal pressure
Pi = 2ST
D
T= 5.8 mm
Pi = To determine
D (OD) = 610 mm
S = 141 Minimum yield strength in tension of pipe material in Mpa
Therefore, by substituting the values in above formula,we get,
Pi = 2.6813115 MPa 273.4877 m head
1.1 times the internal Design Pressure 300.8365 m head
Maximum operating pressure of pipeline 62 m head (As per hydraulic design)
Maximum Static Pressure of pipeline 55 m head (As per hydraulic design)
Calculated Surge Pressure 0.494869 m head
Further, As per clause 6.17.3(a),
sum of the maximum operating pressure or the
maximum pipeline static pressure which ever is 62.494869 m head
higher and the calculated surge pressure
Check OK
pressure in m
ydraulic design)
ydraulic design)
Table 6.7 Values of E for different Materials Table 5 Preferred Dimensions and Mass per meter len
(CPHEEO Manual Page 163) Steel Pipes (IS 3589:2001 page 6)
Material E (Kg/m^2) Outside Diameter (OD) mm
Ductile Iron 1.7E+10 610
Steel 2.1E+10
711
813
Material Yield Stress (MPa)
Ductile Iron 300
Steel 914
Fe330 195
Fe410 235
Fe450 275
imensions and Mass per meter length of Table 5 Preferred Dimensions and Mass per meter length of Steel Pipes (IS 3589:2001
Pipes (IS 3589:2001 page 6) page 6) All dimensions in millimetres [e=K(.5+.001DN)]
Thickness mm Mass Kg/m Nominal Diameter External Diameter Barrel Wall Thickness 'e'
5.8 DN DE K7 K8
6.3 7 8
12.5 80 98 5 6
6.3 100 118 5 6
7.1 125 144 5 6
14.2 150 170 5 6
7.1 200 222 5 6
8 250 274 5.3 6
18 300 326 5.6 6.4
8 350 378 6 6.8
8.8 400 429 6.3 7.2
10 450 480 6.6 7.6
17.5 500 532 7 8
600 635 7.7 8.8
700 738 9 9.6
750 790 9.7 10
800 842 10.4 10.4
900 945 11.2 11.2
1000 1048 12 12
1100 1152 14.4 14.4
1200 1255 15.3 15.3
1400 1462 17.1 17.1
1600 1668 18.9 18.9
1800 1875 20.7 20.7
2000 2082 22.5 22.5
ngth of Steel Pipes (IS 3589:2001
[e=K(.5+.001DN)]
Barrel Wall Thickness 'e'
K9 K10
9 10
6 5.8
6 6.0
6 6.3
6 6.5
6.3 7.0
6.8 7.5
7.2 8.0
7.7 8.5
8.1 9.0
8.6 9.5
9 10.0
9.9 11.0
10.8 12.0
11.3 12.5
11.7 13.0
12.6 14.0
13.5 15.0
14.4 16.0
15.3 17.0
17.1 19.0
18.9 21.0
20.7 23.0
22.5 25.0
