Civil Engineering - Water Supply Engineering - Discussion
Discussion Forum : Water Supply Engineering - Section 8 (Q.No. 3)
3.
The difference in the reservoir level and the lowest point of the water mains is 180 m. The expected pressure due to water hammer is 7.5 kg/cm2 in a pressure conduit of diameter 1 m. Assuming the efficiency of the riveted joints of the pipe as 0.6 and minimum cover 3 mm for corrosion, the thickness of the pipe materials, is
Discussion:
5 comments Page 1 of 1.
Santosh Kumar said:
3 years ago
@Gubendhiran.
Your solution is correct apart from a few errors.
1. It's a steel pipe not a CI pipe in question and we know for steel pipe f=122600 KN/m2. {What you've given i.e. 1260 is its value in kg/cm2} (given in various textbooks esp SK Garg).
2. After calculation, it will be EXACTLY 17 mm. Add 3mm for corrosion and answer =20mm. So, option C is correct.
Your solution is correct apart from a few errors.
1. It's a steel pipe not a CI pipe in question and we know for steel pipe f=122600 KN/m2. {What you've given i.e. 1260 is its value in kg/cm2} (given in various textbooks esp SK Garg).
2. After calculation, it will be EXACTLY 17 mm. Add 3mm for corrosion and answer =20mm. So, option C is correct.
(2)
Gubendhiran said:
8 years ago
t=[(PD)/(2f£)]+3mm
P=internal pressure=static head pressure(Ps) + water hammer pressure(Ph)
Ps=static head *9.81=___kN/m2
Ph=directly given=___kN/m2
f=permissible tensile stress of pipe materials
f=CI Pipe=77000 kN/m2
f=steel pipe=126000 kN/m2
£=efficiency of joint.
Welded=0.9 ; Double rivited=0.75;
Single rivited=0.63
3mm=allowance for correction
Ps=180*9.81=1765.8kN/m3
Ph=7.5*9.81*100*100=735.75kN/m2
P=1765.8+735.75=2501.55kN/m2
t=[(2501.55*1)/(2*77000*0.6)]+3mm
t=0.02707m+3mm
t=27+3
t=30mm.
So answer E is correct.
P=internal pressure=static head pressure(Ps) + water hammer pressure(Ph)
Ps=static head *9.81=___kN/m2
Ph=directly given=___kN/m2
f=permissible tensile stress of pipe materials
f=CI Pipe=77000 kN/m2
f=steel pipe=126000 kN/m2
£=efficiency of joint.
Welded=0.9 ; Double rivited=0.75;
Single rivited=0.63
3mm=allowance for correction
Ps=180*9.81=1765.8kN/m3
Ph=7.5*9.81*100*100=735.75kN/m2
P=1765.8+735.75=2501.55kN/m2
t=[(2501.55*1)/(2*77000*0.6)]+3mm
t=0.02707m+3mm
t=27+3
t=30mm.
So answer E is correct.
Albany Nia said:
8 years ago
Anyone knows the solution.
Xabi alonso said:
8 years ago
Explain the Solution.
Airis ramos said:
10 years ago
Solutions please?
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