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Pvc Pressure Pipes We offer a range of PVC Pressure Pipes that are available in a variety of elegant designs. This pipes are kept simple and sophisticated, fulfilling the needs to our high end customers. The classic designs and the quality materials make these PVC Pressure Pipes more durable and long lasting.
| Specifications |
Aroma's uPVC pressure pipes confirm to IS-4985 specifications and range from 20 mm to 315 mm. They are marketed under the brand name ‘Aroma’.
They are manufactured from new-generation pipe extruder that gives a smooth, glossy and free-flowing inner surface. They are extremely light-weight and available in standard lengths of 6 m, to reduce the number of joints. This saves costs and time for installation and transportation. |
 Application |
- Agricultural and Irrigation Systems
- Potable water supply
- Power and telecommunication
- cable ducting
- Rural and urban Water Supply Systems
- Gas and oil supply lines
- Industrial effluent disposal
- Sewerage and drainage systems
- Building installations
- Air-conditioning ducting
- Industrial ducting
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| Installation |
While designing the pipeline system, the level and depth of the trench is calculated depending on factors such as the terrain and function of the pipeline.
Excavation and pipe-laying must take place simultaneously, as leaving trenches open for too long, makes them unsuitable for use. A fine layer of sand should be spread on the trench-bed, to avoid mechanical damage arising due to the pipe coming in direct contact with the solid bed. Likewise, it is also recommended to put a layer of fine sand on top of the pipe, before filling and carrying the soil to cover the trench. As pipe-laying advances, trenches must be back-filled immediately. The pipe-joints, however, should be left exposed till after the pipeline system has been tested. The minimum width of the trench must be equal to the pipe diameter, plus 300 mm. At the crown of the pipe, the trench-width must not exceed the pipe diameter plus 600 mm. |
| Design |
1. Basic parameters
1.1 Water Quantity (Q) : The amount of water required to irrigate the land, considering crop patterns and irrigation frequency. (in litres / second)
1.2 Length of the Pipeline (L) : The length of the pipe, from source to destination of discharge point. (in metres)
1.3 Static Head (h) : The level difference between the lowest and the highest levels of the pipe.
(in metres)z
2. Selection of Pipe
For best efficiency and optimum output, use the flow chart available in the Aroma Product Catalogue. It is suggested that one should select the pipe-size at an intersection of velocity |
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1 m/sec and discharge Q ( in litres/second). Frictional losses (h2) are also to be taken care of (shown in the section drawing).
2.1 Frictional losses can also be calculated by the empirical Hazen Williams Formula
V=4.567X10-3 X C X D0.63 X S0.54
where V=Velocity of fluid flowing through the pipe D=Internal Diameter of the pipe
C=Hazen Williams co-eff. for PVC (150) S=Hydraulic Gradient
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3. Guideline for Pressure class Selection
The total head (H) acting on the pipe at a particular point, is calculated as H=h1+h2+10%(h1+h2) (in m/km)
Where 10%(h1+h2) is the safety factor for
losses in valves and fittings.
The selection of pipe pressure class can then
be done from the table as below :
3.1 The thumb-rule principle is
1 kgf/cm2 =10 m of water column
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4. Selection of Pump
The formula is : HP of the pump=Q x H/75 x h
where h = efficiency of the pump in % (i.e. 65%)
Now, from the Aroma Pump Section Manual, select the most suitable model.
It is again advised to perform a reverse calculation, to check the pressure class after pump selection.
5. Water Hammer Effect
Water hammer (or, more generally, fluid hammer) is a pressure surge or wave caused by the kinetic energy of a fluid in motion, when it is forced to stop or change direction suddenly. Moving water in a pipe has
kinetic energy µ mass velocity2
This gives rise to a fluctuation in pressure – both above and below the normal working pressure, causing elastic deformation of both liquid and pipe. As the surge pressure is at an extreme level and special protection equipment must be used for safety. However, as PVC is an elastic material, this effect can be ignored for calculating pressure ratings.
6. Selection and Installation of Air Valves
An air valve in the pipeline, functions the way our nose does. This is one of the most critical – yet often neglected, components in an uPVC pipeline.
Since air is compressible in nature, it tends to accumulate in the pipeline. A non-functional air valve causes the accumulated air to generate very high localized pressure. This cannot be read on a conventional pressure gauge. To avoid such an occurrence, air valves should be installed at distances of 300 to 400 m, at all peak-points throughout the pipeline.
6.1 Types of air valves
6.1.1 Single-acting
6.1.2 Double-acting
Kindly refer the valve manufacturer’s catalogue for installation specifications of air valves. In principle, it is advised that the size of the air valve be about one-fourth the diameter of the pipe, for admission as well as release of air.
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| Parameters |
| Guidelines for Friction-loss in uPVC Pipes |
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| Hazen-Williams Constant for flow for the same diameter pipe |
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Derating factor as a Function of Operating Temperature
The max. working pressure is giving by multiplying the nominal pressure PN by the derating factor. |
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| Requirement of uPVC Adhesive for Jointing |
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