1. Conveyance of water & Pipe Appurtenances

2. Conveyance of Water

3. Conveyance of Water
If the source of supply is underground water, usually there is no problem as, these sources are mostly in the underground of the city itself. The water is drawn from the underground sources by means of tube-wells and pumped to the over-head reservoirs, from where it is distributed to the town under gravitational force. Hence at such places there is no problem of conveyance of water from sources to the treatment works.

4. Conveyance of Water

5. Conveyance of Water
In case of sources of water supply is river or reservoir and the town is situated at higher level, the water will have to be pumped and conveyed through pressure pipes. If the source is available at higher level than the town, it is better to construct the treatment plant near the source and supply the water to the town under gravitational forces only,

6. Types
Gravity
Canals
Flumes
Aqueducts
Pressure
Pipes

7. Conveyance of Water

8. Conveyance of Water Open Channels-Canals
These ae occasionally used to convey the water from the source to the treatment plant. These can be easily and cheaply constructed by cutting in high grounds and banking in low grounds.
The channels should be lined properly to prevent the seepage and contamination of water. As water flows only due to gravitational forces, a uniform longitudinal slope is given. The hydraulic gradient line in channels should not exceed the permissible limit otherwise scouring will start at the bed and water will become dirty. In channel flow there is always loss of water by seepage and evaporation,

9. Open Channels

10. Conveyance of Water Aqueducts
Aqueducts is the name given to the closed conduit constructed with masonry and used for conveying water from source to the treatment plant or point of distribution. Aqueduct may be constructed with bricks, stones or reinforced cement concrete. In olden days rectangular aqueduct were used, but now a days horse-shoe or circular section are used. These aqueduct are mostly constructed with cement concrete The average velocity should be 1 m/sec.
They do not flow under pressure as they are not allowed to run full (Tension will cause structural instability-cracks-causing leakage, contamination).

11. Aqueducts

12. Conveyance of Water Tunnels
This is also a gravity conduit, in which water flows under gravitational forces. But sometimes water flows under pressure and in such cases these are called pressure tunnels. Grade tunnels are mostly constructed in horse-shoe cross-section, but pressure tunnel have circular cross-section. In pressure tunnels the depth of water is generally such that the weight of overlying material will be sufficient to check the bursting pressure. Tunnels should be water tight and there should be no loss of water.

13. Tunnels

14. Conveyance of Water Flumes
These are open Channels supported above the ground over trestles etc.. Flumes are usually used for conveying water across valleys and minor low lying areas or over drains and other obstruction coming in the way. Flumes may be constructed with R.C.C, wood or metal. The common section are rectangular and circular.

15. Flumes

16. Conveyance of Water Pipes
These are circular conduits, in which water flows under pressure. Now a days pressure pipes are mostly used at every places and they have eliminated the use of channels, aqueducts and tunnels to a large extent. These are made of various materials like cast Iron, wrought Iron, steel, cement Concrete, asbestos, cement, timber, etc.. In the town pips are also used for distribution system. In distribution system pipes of various diameter, having many connections and branches are used. Water pipe lines follow the profile of the ground water and the location which is most economical, causing less pressure in pipes is chosen.

17. Pipes

18. Forces acting on Pressure Conduits
Internal pressure of water including water hammer pressure- to be resisted by using materials strong in tension.
Pressure due to external loads in the form of backfill, traffic loads, etc.- to be resisted by using materials strong in compression.
Longitudinal temperature stresses created when pipes are laid above the ground- to be resisted by providing expansion joints.
Longitudinal stresses created due to unbalanced pressure at bends or at points of changes of cross section- to be resisted by holding the pipe firmly by anchoring it in massive blocks of concrete or stone masonry.
Flexural stresses produced when pipes are supported over trestles.

19. Conveyance of Water = working pressure * factor of safety
 actual maximum pressure (including abnormal conditions such as water hammer) to which the pipe will be subjected during its operation
Design Pressure
 maximum pressure for which the pipe has been designed
= working pressure * factor of safety
Test Pressure
 maximum pressure which the pipe can withstand without any leakage when tested for hydrostatic pressure

20. Conveyance of Water
The cost of pipe line depends on the internal pressure to bear and the length of pipe line. Therefore as far as possible the hydraulic line is kept closer to the pipe line. In the valley or low points a scour valve is provided to drain the line and removing accumulated suspended matter. Similarly at high points air relief valves are provided to remove the accumulated air. To prevent the bursting of pipes due to water hammer, surge tanks or stand pipes are provided at the end of pipes.

21. Conveyance of Water
The selection of material for the pipes is done on the following points
Carrying Capacity of the pipes
Durability and life of the pipe
Type of water to be conveyed and its corrosive effect on the pipe material.
Availability of funds
Maintenance cost, repair etc..
The pipe material which will give the smallest annual cost or capital cost will be selected, because it will be mostly economical.

22. Conveyance of Water

23. Conveyance of Water Following types of pipes are commonly Used
Cast Iron Pipes
Steel Pipes
Reinforced cement Concrete Pipes
Plastic or PVC pipes
Asbestos cement pipes
Copper and lead pipes
Wooden pipes
Vitrified Clay pipes
Miscellaneous Pipes

24. Conveyance of Water
Out of the types mentioned, plastic or PVC and Asbestos cement pipes, wooden pipes are not generally used for conveyance of water. They are used in house drainage or water connection within individual house.

25. Cast Iron Pipes
Cast – Iron Pipes are mostly used in water supply schemes. They have higher resistant to corrosion, therefore have long life about 100 years.
Cast Iron pipes are manufactured in lengths of 2.5 m to 5.5 m. The fittings of these pipes are also manufactured in sand molds having core boxes. These fittings are also weighed, coated with coal tar and finally tested. Cast-Iron pipes are joined together by means of Bell and Spigot, Threaded or flanged Joints

26. Cast Iron Pipes

27. Conveyance of Water Advantages of CI Pipes Ease in jointing the pipes
Moderate cost
Strong and durable
Have a very long design life. (100 years)
They are less prone to corrosion.

28. Conveyance of Water Disadvantages of CI Pipes
They are heavy and difficult to transport.
Water carrying capacity reduces with time
Cannot withstand high pressures.
Length of pipe available as less (2.5 to 5.5m) so more joints are required for laying the pipes so chances of leakage also Increases.
They are brittle so they break or crack easily while transportation.

29. Conveyance of Water Steel pipes
The Construction of these pipes is similar to wrought iron pipes, it is occasionally used from main lines and at such places where pressure are high and pipe dia is more. Steel pipes are more stronger, have very light weight and can withstand high pressure than cast iron pipes. They are also cheap, easy to construct and can be easily transported.

30. Steel pipes

31. Cannot withstand high negative pressures or vacuums
Steel Pipes
Steel plates of varying thickness for with-standing different pressures are generally bent & welded
Expansion joints are generally not required in steel pipes which are buried under the ground (if exposed to atmosphere, expansion joint may be required)
Get rusted quickly which reduces their life as well as carrying capacities (hence, protected on the inside as well as outside by protective coatings)
Cannot withstand high negative pressures or vacuums
Easily affected by acidic or alkaline waters
Corrosion control: protective coating
 coatings of paint, galvanizing, bituminous compounds, cement linings etc

32. Conveyance of Water
The disadvantages of these pipes is that they cannot withstand external load, if partial vacuum is created by emptying pipe rapidly, the pipe may be collapsed or distorted.
These pipes are much affected by corrosion and are costly to maintain.
The life of these pipes is 25 to 50 years, which is much shorter as compared to cast Iron Pipes.
Steel pipes are not used in distribution system, owing to the difficulty in making connections.
The joints in steel pipes may be made of welding or riveting, longitudinal lap joints are made In riveted steel pipes up to 120 cm dia

33. Conveyance of Water Concrete Pipes
These pipes may be precast or Cast-in-situ plain concrete pipe may be used at such places where water does not flow under pressure, these pipes are jointed with Bel &Spigot Joints. Plain Concrete pipes are up to 60 cm dia only, above it these are reinforced.

34. Reinforced Cement Concrete Pipes

35. Reinforcement  circumferential & longitudinal
Reinforced Cement Concrete pipes
Concrete  1:2:2
Aggregate size  6 mm
Reinforcement  circumferential & longitudinal
 pre-stressed concrete pipes are used for large heads

36. Conveyance of Water Advantages of R.C.C Pipes
Their life is about years.
They can be easily constructed in the factories or at site
They have least coefficient of thermal expansion than other types of pipes . Hence they do not require expansion joints
Due to their heavy weight, when laid under water, they are not affected by buoyancy, even when they are empty.
They are not affected by atmospheric action or ordinary soil under normal condition.

37. Conveyance of Water Disadvantages of R.C.C Pipes
They are affected by acids, alkalis and salty waters
Their repairs are very difficult.
Due to their heavy weight, their transportation and laying cost is more.
It is difficult to make connections in them
Porosity may cause them to leak.

38. Wrought Iron Pipes

39. Conveyance of Water Wrought Iron Pipes
Wrought Iron Pipes are manufactured by rolling the flat plates of the metal to the proper diameter and welding the edges. If compared with cast Iron, these are more lighter, can be easily cut, threaded and worked, give neat appearance if used in the interior works. But it is more costly and less durable than cast iron pipes. These pipes should be used only inside the buildings, where they can be protected from corrosion. Wrought Iron pipes are joined together by couplings or screwed and socketed joints. To Increase the life of these pipes sometimes these are galvanized with zinc.

40. Hume Steel Pipes Vitrified Clay Pipes
Consist of thin steel shell coated from inside & outside with cement mortar (1:2)
Heavy and difficult to handle
Vitrified Clay Pipes
Vitrification is a process which fuses the clay particles to a very hard, inert, glass-like state
Used for carrying sewage & drainage
Weak in tension
Free from corrosion-smooth hydraulically efficient surface.

41. Asbestos Pipes
Material: asbestos cement – asbestos, silica & cement subjected to pressure
Benefits: light, easy to transport, easily assembled, high resistance to corrosion, highly flexible, bad conductor of heat & electricity, flexible joints, not affected by most of the chemicals, very smooth and hydraulically efficient
Demerits: Costly, Brittle, Soft, Liable to get damaged
Application: water supply, irrigation, cover for the underground wires, small size distribution pipes

42. Miscellaneous types of conduits
Materials like copper, wrought iron, plastics etc. may be used for manufacturing piped conduits
Wrought Iron Pipes: Lighter than CI pipes, more costly, neat, used for indoor works, corrode quickly, less durable
Copper pipes: highly resistant to acidic & alkaline water
Plastic pipes: lighter & free from corrosion, low strength, less durable, cannot withstand high temperatures.

43. FIRE HYDRANTS
Outlet provided in a distribution main or a sub-main for tapping water, mainly during fires.
During a fire breakout, a nearby hydrant is connected to a fire hose, and the water may be used for extinguishing the fire.
Generally provided at street crossings and turnings.

44. REQUIREMENTS OF A GOOD HYDRANT
Should connect easily to hose or motor pump.
Cheap
Easily detectable
Should not get out of order
Allow undisturbed water flow

45. TYPES OF HYDRANTS
Post Fire Hydrant- Remains standing above the ground like a post by about 0.9m to 1.2 m; easy to detect, prone to damage.
Flush Fire Hydrant- Installed underground in a brick or a cast iron chamber with its top cover slightly above the street level; difficult to detect, less prone to damage.

47. Pipe Joints
For the facilities in handling, transporting, and placing in position, pipes are manufactured in small lengths of 2 to 6 meters. These small pieces of pipes are then joined together after placing in position to make one continuous length of pipe.
The design of these joints mainly depends on the material of the pipe, internal water pressure and the condition of the support
The bell and spigot joints, using lead as filling material is mostly used for cast Iron pipes. For Steel pipes welded, riveted, flanged or screwed joints my be used.

48. Joints used in cast iron pipes
(i) Socket & spigot joint
 somewhat flexible & allows the pipes to be laid on flat curves
(ii) Flanged joint
 used for pumping stations, filter plants, and at other locations where it may be necessary to occasionally disjoint the pipe
(iii) Mechanical joint called dresser coupling
 used when it is required to join the plain ends of cast iron pipes
Flexible joint
 used when large scale flexibilities are required
Expansion joint
 provided at suitable intervals in the pipe lines, so as to counteract the thermal stresses

49. Flange
Flanged joint
Flexible joint
Mechanical joint

50. Various types of Joints which are mostly used, are as follows
Spigot and Socket Joints or Bell & Spigot Joints
Expansion Joints
Flanged Joints
Mechanical Joints
Flexible Joints
Screwed Joints
Collar Joints
A.C. Pipe Joints

51. Spigot and Socket Joints
This types of joints is mostly used for cast iron pipes For the construction of this joint the spigot or normal end of one pipe is slipped in socket or bell mouth end of the other pipe until contact is made at the base of the base of the bell.

52. Spigot and Socket Joints

53. Spigot and Socket Joints
After this hemp or yarn is wrapped around the spigot end of the pipe and is tightly filled in the joint by means of yarning iron up to 5 cm depth. The hemp is tightly packed to maintain regular annular space and for preventing jointed material from falling inside the pipe. After packing of hemp & gasket or joint runner is clamped against the outer edge of the bell.

54. Spigot and Socket Joints
Sometimes wet clay is used to make tight contact between the runner and the pipe so that hot lead may not run out of the joint spaces. The molten lead is then poured into V- shaped opening left in the top by the clamp joint runner. The space between the hemp yarn and the clamp runner is removed, the lead which shrink while cooling, is again tightened by means of chalking tool and hammer. Now a days in order to reduce the cost of lead certain patented compounds of sulphur and other materials and other materials are filled in these joints.

55. Expansion Joints
This joint is used at such places where pipes expand or contract due to change in atmospheric temperature and thus checks the setting of thermal stresses in the pipes. In this joints the socket end is flanged with cast iron follower ring, which can freely slide on the spigot end or plane end of other pipes. An elastic rubber gasket is tightly pressed between the annular spaces of socket by means of bolts. In the beginning while fixing the follower ring some space is left between the socket base and the spigot end for the free movement of the pipes under variation of temperature. In this way when the pipe expands the socket end moves forward and when the pipe contracts, it moves backward in the space provided for it. The elastic rubber gasket in every position keeps the joint water tight.

56. Expansion Joints

57. Flanged Joint
This joint is mostly used for temporary pipe lines, because the pipe line can be dismantled and again assembled at other places.
The pipe in this case has flanges on its both ends, cast, welded or screwed with the pipe. The two ends of the pipes which are to be jointed together are brought in perfect level near one another and after placing of washer or gasket of rubber, canvas, copper or lead between the two ends of flanges is very necessary for securing a perfect water-tight joints. These joint cannot be used at places where it has to bear vibration of pipes etc..

58. Flanged Joint

59. Flexible Joints
Sometimes this joint is also called Bell & Socket or Universal Joint. This joint is used at such places where settlement is likely to occur after the lying of the pipes. This joint can also be used for laying of pipes on curves, because at the joint the pipes can be laid at angle. This is a special type of joint. The socket end is cast in a spherical shape. The spigot end is plain but has a bead at the other end. For the assembling of this joints, the spigot end of one pipe is kept in the spherical end of the other pipe.

60. Flexible Joints

61. Flexible Joints

62. Flexible Joints
After this the retaining ring is slipped which is stretched over the bead. Then a rubber gasket is moved which touches the retainer high. after it split cast iron gland ring is placed, the outer surface of which has the same shape as inner surface of socket end. Over this finally cast iron follower ring is moved and is fixed to the socket end by means of bolts. It is very clear that if one pipe is given any deflection the ball shaped portion will move inside the socket, and the joint will remain waterproof in all the position.

63. Flexible Joints

64. Mechanical Joints
This type of joints are used for jointing cast Iron, Steel or wrought Iron pipes, when both the ends of the pipes are plain or spigot. There are two types of mechanical joints.
Dressers- Couplings
It essentially consists of one middle ring, two follower rings and two rubber gaskets. The two follower rings are connected to-gather by bolts and when they are tightened, they pass both the gaskets tightly below the ends of the middle ring. These joints are very strong and rigid and can withstand vibrations and shocks up to certain limit. These joints are mostly suitable for carrying water lines over bridges, where it has to bear vibrations.

65. Mechanical Joints

66. Mechanical Joints

67. Screwed Joints
The joint is mostly used for connecting small diameter cast iron, wrought iron and galvanized pipe. The end of the pipes have threads outside, while socket or couplings has threads on the inner side. The same socket is screwed on both the ends of the pipes to join them. For making water tight joints zinc paint or hemp yarn should be placed in the threads of the pipes, before screwing socket over it.

68. Screwed Joints

69. Collar Joint
This type of joint is mostly used for joining big diameter concrete and asbestos cement pipes. The ends of the two pipes are brought in one level before each other. Then rubber gasket between steel rings or jute rope socked in cement is kept in the grove and the collar is placed at the joint so that it should have same lap on both the pipes. Now 1:1 cement mortar is filled in the space between the pipes and the collar.

70. Collar Joint

71. Pipe Appurtenances

72. Pipe Appurtenances
To isolate & drain the pipe line sections for tests, inspections, cleaning & repairs
Examples:
(i) gates
(ii) valves
(iii) manholes
(iv) insulation joints
(v) expansion joints
(vi) anchorages etc.

73. Pipe Appurtenances Gates & Valves in Pipe Lines
Gate valves or Sluice valves
 used to regulate the flow
 located at suitable intervals
 helpful during repair works
 usually placed at summits
The valve is made of cast iron with brass, bronze or stainless steel mountings

74. Pipe Appurtenances Gates & Valves in Pipe Lines Air valves
 generally placed along the pipe line at summits on both sides of the sluice and also on the downstream side of all other sluice valves
 air-inlet & air relief valve

75. Pipe Appurtenances Gates & Valves in Pipe Lines
Blow off valves or Drain valves or Scour valves
 provided at low level points to remove the entire water from within pipe for inspection, repairs, etc

76. Pipe Appurtenances Gates & Valves in Pipe Lines Pressure-relief valves
 to reduce water hammer pressures
 adjusted to open & close automatically with pressure in the pipe

77. Pipe Appurtenances Gates & Valves in Pipe Lines
Check valves or Reflux valves
 also called non-return valve (NRV)
 installed on the delivery side of the pumping set
 also installed on pump discharges to reduce water hammer forces on the pump
 also required at inter-connections between a polluted water system & a potable water system

78. Swing type check valve
check valve

79. Pipe Appurtenances Manholes
 provided at suitable intervals along the pipe line, so as to help its laying, & to serve for inspections & repairs
 usually provided in case of steel, hume steel or RCC pipes
 less common on cast iron pipes
Insulation Joints
 to insulate the pipe against the flow of stray electric current
Anchorages
 at bends, on steep slopes etc

80. Testing of the Pipe Lines – pressure test
 tested from section to section
 the pipe is kept under pressure for 24 hours & inspected for possible defects, leakages at the joints, etc.
Disinfection of Pipe Lines before use
 pipe must be disinfected before carrying treated water
 50 mg/l of chlorine residue is maintained for 12 hours

81. Laying of Water Supply Pipes
Pipes are generally laid below the ground level, but sometimes when they pass in open areas, they may be laid over the ground. The pipes are laid in the following way.
First of all the detailed map of all roads, streets lanes etc., is prepared. On this map the proposed pipe line with all sizes and length will be marked. The position of existing pipe line, curb lines, sewer lines etc.. will also be marked on it. In addition to this position of valves and other pipe specials, stand posts etc.. will also be marked, so that at the time of laying there should be no difficulty in this connection.

82. Laying of Water Supply Pipes
After the general planning, the center line of the pipe line will be transferred on the ground from the detail plan. The center line will be marked by means of stalkes driven at 30 m interval on straight lines. On curves the stalkes will be driven at 7 to 15 m spacing. If the road or streets have curbs, the distance of center of pipe line from curb will be marked.

83. Laying of Water Supply Pipes
When the center line has marked on the ground the excavation for the trenches will be started. The width of the trench will be 30 cm to 45 cm more than the external diameter of the pipe. At every joint the depth of excavation will be 15 to 20 cm more for one meter length for easy joining of the pipes. The pipe lines should be laid more than 90 cm below the ground so that pipe may not break due to impact of heavy traffic moving over the ground

84. Laying of Water Supply Pipes

85. Laying of Water Supply Pipes
After the excavation of trenches the pipes are lowered in it. The pipe laying should start from lower level and proceed towards higher level with socket end towards higher side. The jointing of pipes should be done along with the laying of pipes.
After laying the pipe in position, they are tested for water leakage and pressure.
When the pipe line is tested, the back filings of the excavated material will be done.
The soil which was excavated is filled in the trenches all around the pipes and should be well rammed. All the surplus soil will be disposed off and the site should be cleaned.

86. Laying of Water Supply Pipes

87. Laying of Water Supply Pipes

88. Laying of Water Supply Pipes

89. Hydrostatic Test
After laying the new pipe line, jointing & back filling, it is subjected to the following tests:
Pressure Tests at a pressure of at least double of maximum working pressure, pipe joints shall be absolutely water tight.
Leakage Test (to be conducted after the satisfactory completion of the pressure test) at a pressure as specified by the authority for a duration of two hours.
In this way error in workman ship will be found immediately and can be rectified. Usually the length to be tested is kept up to 500 m.

90. Laying of Water Supply Pipes