Transcript Water Supply Networks: Kinds, Structures and Design

Topic I.8. Water Supply Networks:
Kinds, Structures and Design
Kinds of Water Supply Networks
I. According to the hydraulic connections
 Branched
 Looped (Gridiron)
II.
According to the static
arrangement
 Non-stratified (Non-zone)
 Stratified (Zone)
head
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Kinds of Water Supply Networks
a. Branched
b. Looped (Gridiron)
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Kinds of Water Supply Networks
Zone Network with Steep Terrain
a - Gravity System
1 - minimal static head
б - Pumping System
2 - maximal static head (H < 60 m)
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Zonal (Stratified) Network
a - Sequencing pumping zones feeding
б - Combined gravity and pumping zones feeding
b - Two pumping groups
г - Single pumping group
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Water Supply Networks Structures
Main Elements
 Mains (Trunks)
 Branches
 Fittings
 Valves
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Mains (Trunks) Design
Basic Requirements
 Main direction of the trunks must comply to the main water
distribution direction. For this equally loaded parallel trunks have
to be established at distance of about 300 - 600 m each to the other
 The trunks along the main water distribution direction have to be
connected with intermediate trunks at distance of about 400 - 800
m each to the other
 So designed trunks and the rings formed by them have to cover
uniformly the settlement, passing through the most dense
populated regions and by the big local consumers
 The trunks permanent ways have to be located at the higher parts
of the settlements, which will insure uniform spatial distribution of
the water dynamic head
 The trunks permanent ways have to consider the soil properties, as
well as the underground communications
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Branches Design
Basic requirements
 The distribution branches are laid out along any one of the streets
in the settlement in the way to deliver water with the shortest
permanent way from the nearest trunk to the consumers
 At the streets broader than 16 m two parallel branches could be
install. If the branch diameter exceeds 300 mm, it is constructed as
a transit one and a parallel branch with smaller diameter
distributes water towards the attached consumers
 Minimal slope of the branches is normally 0,1 %, or no less than
0,05 % at flat terrain
 Stop valves have to be envisaged at the points of the trunks
branching and at the beginning and the end of every branch in the
way to allow distribution network rings to be isolated in a case of
emergency
 Fire valves have to be envisaged, uniformly distributed on the
water supply network and at no more than 100 (150) m distance
each to the other
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Pipes, Fittings and Valves
Distribution Networks Pipes
Materials
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Cast iron
Steel
Asbestos cement
Plastics - PE, PP, PVC
Pipes joints
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Socket (muff, muffle)
Flange
Clutch (union)
Weld
Gluing
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Pipes Joints
Cast iron socket
a - pipe longitudinal section
1 - pipe cylindrical end
2 - pipe muff end
б - socket joint detail
3 - resin rope
4 - plumb or asbestos-cement
stuffing
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Pipes Joints
Cast iron pipes sockets
a - socket joint
1 - pipe cylindrical end
2 - pipe muff end
б - screw-socket joint
3 - rubber gasket
4 - screw ring
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Pipes Joints
Asbestos-cement pipes joints
a - “Simplex” type
б - “Gibot” type
1 - rubber gasket
2 - pipe
b - Flange type
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Fittings
Kinds of Fittings
 T-fittings (with or without flanges)
 Cross-fittings (with or without flanges)
 Offsets (with or without flanges), 30o, 45o , 60o and 90o
 Knees (Elbows) - with or without flanges, 45o and 90o
 Reducing fittings (Confussors/Difussors) - with or without flanges
 Duff flanges
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Valves
Kinds of Valves
 Stop (Gate) valves
 Fire hydrants
 Pressure reducing valves
 Air valves
 Blow off
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Valves
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