CONCEPTO POR M2

S.No. Parameter HDPE Pipes GRP Pipes

1. Suitability to Transport up to Field

Pipes & Fittings Material being Tough but Flexible there is no possibility of damages during Transport of Pipe to the field from Manufacturer

Pipes & Fittings are Light, Delicate and Rigid. Damages due to Impacts during Transportation are Very High.

2. In-field Movement

Pipes are Flexible & Tough and hence no possibility of damages during infield Movement and Handling

Pipes being Light, Delicate and Rigid the pipes get damaged / Broken quite Frequently during the Infield Movement.

3. Handling Easy to Handle.

Do not break in handling. Careful Handling is necessary. The pipes get broken easily.

4. Feasibility to Repair

Pipes can be easily Repair on the site itself. The damaged portion can be easily cut off and Welded together with the help of a simple butt-fusion machine.

There is no need for a highly skilled operator for repairing.

For Repairing the damaged pipes skilled personnel are needed.

5. Installation and Operation

Jointing is done by Fully Automatic / Semi- Automatic Butt-Welding / Electro-Fusion machines, whereby eliminating any scope for human errors

Jointing involves Skill & Experience of the operator. Human error is evident depending upon the person to person.

6. Jointing Types Very Wide Range of Jointing to suit almost

all other types of pipe materials. Limited Joint types.

7. Maintenance Zero Maintenance piping system. Unbreakable under Seismic Zones or Unstable soil areas.

Pipeline breaks under Seismic Zones or Unstable soil areas.

8. Aging Pipes are made of Homogeneous Single

material. Further, because of strong UV Protection, Aging process is very Slow and Pipelines may work even upto 100 years.

Because of Compounded Material, Fast Aging of pipe material takes place, Restricting Life of pipe-line to below 30 years.

9. Inside Surface Inside Surface is very Smooth. Inside Surface is not as Smooth as that of HDPE.

10. Nature of Pipe Visco-Elastic Nature. Can be laid along the Contour. Very good for Hilly / Mountainous difficult Terrain also.

Trenching Cost Highly Reduced.

Rigid. Need Flat-Bed trenches. Not Suitable for difficult Terrain. Trenching Cost Increases Highly.

11. Flexibility The Pipe allows a Bending Radius of 25 times the Diameter of Pipe. Reduces the number of Bends and thus Reduce Loss of Head due to Friction.

Pipes are Rigid and use of Bends is must. Increased Loss of Head due to Friction.

Frequently Asked Questions

S.No. Parameter HDPE Pipes GRP Pipes

12. Pumping Energy Lower Pumping Cost due to Lower Frictional Losses. PE pipe has Better Flow characteristics

Higher Pumping Cost due to Higher Frictional Losses. This is easily computed as the “C” value of GRP pipe is much less (16% less) than PE pipe. This leads to more Frictional Loss in GRP Pipe and more energy exerted for Pumping Per Kilo-Litre of Water. This is a recurring drain in the user’s pocket.

13. Shut-down Wave Velocity

The shut-down Wave Velocity is half of what is in GRP piping system.

Safe Leak-Proof Joints. Negligible Maintenance Cost.

The Shut-Down Wave Velocity is Double that of what is in HDPE Piping System.

More Joint Failures and Increased Maintenance Cost.

14. Shut-down

Pressure Change The Shut-down pressure change is also half of what is in GRP Piping System. Safe Leak-proof joints.

Negligible maintenance cost.

The Shut-Down pressure change is double that of what is in HDPE Piping System.

More Joint Failures and Increased Maintenance Cost.

15. Water Hammer & Surge

Because of its Visco-Elastic Nature, absorbs most of the effect of Water Hammer & Surge and Survives without any damage

Rigid. Breaks under Water Hammer & Surge or needs Specials, Valves / Fittings to absorb the effect.

16. Thermal Resistance

PE has good Thermal Resistance and can sustain a wide range of Temperature variations between -40º C to +45º C

GRP becomes Brittle at Low Temperatures and thus prone to breakage.

17. Impact Resistance High Impact Resistance. Can survive Accidental Impacts.

Comparatively Low Resistance to Impacts. The pipes get damaged easily.

18. Compatibility Highly Compatible with other Piping Materials.

Not easily Compatible with other Piping Materials.

19. Environmental Stress Crack Resistance, (ESCR )

Very High ESCR,

hence can be used over ground also.

Low ESCR.

Not suitable for On ground and Over ground applications.

20. Abrasion Resistance

Very good Abrasion Resistance. Gives Very Long Trouble-Free life to

Pipeline, particularly when water is pumped from Rivers, which may contain Silt / Sand Particles.

Prone to Abrasion. Pipes gets Damaged Faster due to Poor Abrasion and need Replacement, particularly when water is pumped from Rivers, which may contain Silt / Sand Particles.

HDPE Vs GRP Pipes

S.No. Parameter HDPE Pipes GRP Pipes

21. Strainability Strainability of PE pipe material is 3 times of GRP. This enables :

- Easy Installation - Less Number of Fittings - Reduced Frictional Loss - Trouble Free Operation - Very Low Maintenance Cost

- Sustains Soil-Settlements & Prism Loads very well

- Sustains through Earthquakes. Kobe, Japan is very good example. The report is officially available.

Strainability of GRP pipe material is 1/3rd _{of PE}

Pipes.

- Installation troublesome

- More number of fittings required - Higher frictional loss

- Breakage trouble - Higher maintenance cost - Succumb to soil-settlements & Prism Loads.

- Pipe-lines break due to earthquakes.

22 Environmental

Effect HDPE is a Thermoplastic Plastic Material which can be recycled and hence is Environmentally friendlier.

GRP is a Thermoset Material which cannot be recycled hence Environmentally Hazardous.

23 Inside Outside Smoothness

Polyethylene pipes manufactured by extrusion have a Smooth Internal & External Surface.

GRP piping based on Thermoset Systems will have either a True Inside Surface or a True Outside Surface but not both surfaces. Pipings made by Filament Winding have a good finish on the Inside while those made by Centrifugal Casting have a Smooth Outside Surface.

24 Water Absorption HDPE pipe have a negligible value of water absorption of 0.03 % and no impact on strength of pipe.

Water absorption of GRP pipes ranges from 0.2 % to 0.8 %. Permeation of this water into the polymer matrix could weaken the glass to resin bond.

List of Major Customers of PE Pipes