water tank pipes

8/2/2019 Water Tank Pipes

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CALCULATION:

Length of pipe, L = 1.58 m

Diameter of pipe, D = 0.020 m

Area of pipe, A =( x(0.02) ) /4

= 3.142x10m

Volumetric flow rate of water = 9.80 L/min

= 1.63310 m/s

Mass flow rate of water = volumetric flow rate of water density of water

= (1.63310 ) 1000

= 0.1633 kg/s

Viscosity of water, = 0.8710 Ns/m

Velocity , v = volumetric flow rate / area of pipe

= (1.63310) / ( 3.142x10)

= 0.52 m/s

Re = (Dv)/

= (0.020.521000) / 0.8710

= 11954.02

Relative roughness factors for pipes

Material

Concrete

Cast Iron

Galvanized IronAsphalted Cast Iron

Commercial or Welded Steel

PVC, Glass, Other Drawn Tubing

Use relative roughness factor for PVC pipe = 0.0015mm

= 1.50 x 10 m

Roughness ration,e = / D

= (1.50x10) / 0.02

= 7.510

PVC ia a type of plastic. So that PVC pipe can also consider as smooth pipe.

Based on the graph of friction factors in pipe flow ,friction factor ,f =0.0070


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Pressure drop due to the friction of pipe :

P = 8fvL/2D

=8(0.007)(1.58)(1000)(0.52) / (2 x 0.02)

=598.12 Pa

V = v/2g

= 0.52/2(9.81)

= 0.01378

Miscellaneous Losses

Entry

Elbow

Gate valve

Globe valve

Tee, used as elbow

Exit

TOTAL

V = kv/2g

= 12.73(0.52)/2(9.81)

= 0.17544 m

Pressure drop due to fitting and bending:

P = g x head loss

= 1000 x 9.81 x 0.17544= 1721.1 Pa

Total Pressure Drop , P = pressure drop due to friction + pressure drop due to fitting and bending

= 598.12 +1721.1

= 2319.22 Pa

= 2.31922 kPa


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TEE,USED AS ELBOW

0.3m

0.06m GATE VALVE(FULLY OPEN)

TEE,USED AS ELBOW

0.45m

0.52m

TEE,USED AS ELBOW

Material of construction for the tank

The material of the construction of the tank is polyethylene water storage tank. The size of water tanks

mostly from 8 gallons to 12000 gallons. All of the polyethylene plastic storage tanks are from FDA approved


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materials and are suitable for collecting and storing water for drinking and other household uses.The shape o

can be vertical (tall round tanks), horizontal (long, low tanks with leg molded in) or rectangular (box shaped

The tank that use for my house is polyethylene .

The advantages of polyethylene water storage tank:

Reliable, Durable, Corrugated wall & Leak proof

Lightweight - easy handling (transportation & installation)

100% non sunlight UV penetration

Extremely Durable & Long Lasting

Rust & Rot Free

Seamless & Odourless

Non-Toxic / Food Grade

Won't rot or peel

Physical properties of polyethylene

Polyethylene is athermoplasticpolymerconsisting of long hydrocarbon chains. Depending on thecrystallinity

and molecule weight,amelting pointandglass transitionmay or may not be observable. The temperature at

which these occur varies strongly with the type of polyethylene. For common commercial grades of medium-

and high density polyethylene the melting point typically in the range 120 to 130 C (248to 266F). The melting

point for average, commercial, low-density polyethylene is typically 105 to 115 C (221to 239F).

Chemical properties of polyethylene

Most LDPE, MDPE and HDPE grades have excellent chemical resistance, meaning that it is not attacked by strong

acid or strong bases. It is also resistant to gentle oxidants and reducing agents. Polyethylene burns slowly with a

blue flame having a yellow tip and gives off an odour of paraffin. The material continues burning on removal of

the flame source and produces a drip.Crystalline samples do not dissolve at room temperature. Polyethylene

(other than cross-linked polyethylene) usually can be dissolved at elevated temperatures inaromatic

hydrocarbonssuch astolueneorxylene, or in chlorinated solvents such astolueneorxylene, or in chlorinatedsolvents such as trichloroethaneortrichlorobenzene.


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From the table which show the properties of construction materials,I think that polyethylene is the m

suitable material to construct the water storage tank.This is because the tensile strenghth of polyethylene

which is 6 - 37MPa which is more than enough to support the pressure of water in tank which is only

0.0064746 MPa. Furthermore, polyethylene is very resistant toward corrosive liquid such as acid and alkali.

Thus, it is safe to be used as the water storage tank in our house.

Pressure of water tank = gh= 10009.81o.66

=6474.6 Pa

=0.0064746 M Pa

Pressure of water in tank Is 0.0064746 MPa

PIPE MATERIAL

The pipe material that use for my house is PVC pipe,which is know as polyvinyl chloride pipe which is

made from a plastic and vinyl combination material. The pipes are durable,hard to damage, does not rust anlong lasting.This is the reason PVC pipe is commonly used in water systems,underground wiring ,and sewer

Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely-produced plastic, after

polyethylene and polypropylene. PVC is widely used in construction because it is durable, cheap, and easily

worked.

It is used forsewerage pipesand other pipe applications where cost or vulnerability tocorrosion

limits the use ofmetal.PVC pipes can be fused together using various solvent cements or heat-fused,

creating permanent joints that are virtually impervious to leakage.

Besides that ,PVC pipe also safe to use.PVC is a useful material because of its inertness and is the basic ofits low toxicity.The main health and safety issuse with PVC are associated with "VCM", its carcinogenic precursor

,the products of its incineration (dioxins under some circumstances),the addives mixed with PVC,which include

heavy metals and potential endocrine disruptors.

ADVANTAGES OF PVC PIPE:

1).Healthy: ppr pipe material

2).Attrictive shape and light weight:little fluid resistance; soft color, beautiful shape; only1/8 that of metal pipe


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3).Energy saving and heat preservation:coefficient of heat conduction is only0.5% that of metal pipe.

4).Strong high temperature endurance:long-term service temperature:70. Short-term service temperature:95'

5).High pressure endurance:highest normal pressure can reach 95

6).Long service life:,over 50 years.

7).Convenient and reliable installation:hot melt connection, a connection can be finished within seconds

Physical Properties of PVC (Polyvinyl chloride)

Property

Density [g/cm3]

Thermal conductivity [W/(mK)]

Yield strength [MPa]

Young's modulus [psi]

Flexural strength (yield) [psi]

Compression strength [psi]

Coefficient of thermal expansion (linear) [mm/(mm C)]

Vicat B [C]

Resistivity [ m]

Surface resistivity []

By referring to the table above, polyvinyl chloride is suitable to be used as the material to make

pipes because it has high tensile strength which can withstand high tensile strength which can withstand

high pressure of water.


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(mm)

0.3 - 3.0

0.26

0.150.12

0.045

0.0015


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k Quantity Total

0.5 1 0.5

0.8 2 1.6

0.13 1 0.13

6 1 6

1.5 3 4.5

1 0 0

12.73


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ELBOW

0.25m

GLOBE VALVE

WATER TANK


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Rigid PVC Flexible PVC

1.3-1.45 1.1-1.35

0.14-0.28 0.14-0.17

31-60

490000

10500

9500

510-5

65-100

10 16 1012-1015

1013

-1014

1011

-1012


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WATER TANK


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GLOBE VALVE FULLY OPEN GATE VALVE


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commonplastic. The annual production is approximately 80 million metric tons.[1]

Its primary use is

withinpackaging(plastic bag, plastic films,geomembranes, etc.). Many kinds of polyethylene are known, but they

almost always have thechemical formula(C2H2)nH2. Thus PE is usually a mixture of similarorganic compoundthat

differ in terms of the value of n.

thecrystallinityandmolecular weight, amelting pointandglass transitionmay or may not be observable.

The temperature at which these occur varies strongly with the type of polyethylene. For commoncommercial grades of medium- and high-density polyethylene the melting point is typically in the range 120

to 130 C (248to 266F). The melting point for average, commercial, low-density polyethylene is typically

105 to 115 C (221to 239F).

by strong acids or strong bases. It is also resistant to gentle oxidants and reducing agents. Polyethylene

burns slowly with a blue flame having a yellow tip and gives off an odour of paraffin. The material continues

burning on removal of the flame source and produces a drip.Crystalline samples do not dissolve at room

temperature. Polyethylene (other than cross-linked polyethylene) usually can be dissolved at elevated

temperatures inaromatic hydrocarbonssuch astolueneorxylene, or in chlorinated solvents such

astrichloroethaneortrichlorobenzene.

water tank pipes

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