1.What are PE Pipes : PE Pipes are Plastics Pipes made from Polyethylene (PE) Raw Material, which is the major thermoplastic produced globally (others are Polypropylene or PP, and Poly-Vinyl Chloride or PVC).

PE is one of the major commodity Polymers manufactured from Petrochemicals. The PE raw material (for Piping, Extrusion, Injection Moulding, Blow Moulding, Film, etc)comes in the form of granules, and is supplied by Companies like IPCL, GAIL, IOCL, RIL, HPL (in India) and Borouge, Borealis, Basell, Total Petro, Ineos, SABIC, Prime Polymers, Thai PE, etc.(globally).(Fig.1) The PE Pipe raw material grades are specified as PE63 , PE80, and now the third generation, as PE100.

Over the years, scientists have improved the PE Pipe grade on properties which are required for improved/foolproof performance in the field. The  present third generation raw material, PE100, is an improvement over PE80 and PE63 basically on three parameters : MRS (Minimum Required Strength at 20oC & min. 50 year life), SCG (Slow Crack Growth), and RCP (Rapid Crack Propagation). Importantly, the wall thicknesses of Pipe also came down due to these technical improvements, by as much as 35%, leading to cost reduction as well as increased ID for fluid flow.

Some of the technically leading Petrochemical Companies (present outside India) are providing pre-compounded materials with low sag property, making it possible to produce large diameter Pipes upto 2500 mm OD (JISL has the capacity to make PE Pipes & Fittings upto 2000mm, in Indai).(globally).(Fig. 1)Pre-Compounded grades lend themselves to better processability and have better carbon (or other colour) dispersion leading to uniform and improved UV resistance across the matrix.

2.Why PE Pipes : Of all the Pipes used globally, Plastics (PE and PVC) Pipes form around 40% share (Fig. 2). India is no exception to this, although there is a slight lag in under-standing of Plastics as Piping materials. Designers & Utility authorities used to stick to the traditional Piping and were seen not taking risks with materials they did not know. This is definitely changing now with the world wide popularity of PE Piping (Fig.3 & 4).

Region	1990 (KT)	Growth %	2000 (KT)	Growth %	2010 (KT)
Asia	95	27.9	360	21.9	1150
Japan	70	2	84	1.9	100
M. East	25	26	90	11.1	190
S. Africa	25	18	70	12.9	160
Africa	20	20	60	7.5	105
E. Europe	80	12.5	180	9.2	345
W. Europe	395	9	750	7.7	1330
NAFTA	335	16.9	900	7.8	1600
TOTAL	1045	13.9	2494	10	4980

PE Pipe End-Use Segment	2011 (KT)	2015 (KT)
Trade-Agri	54	95
Water	39	65
Sewerage		14
Industrial	25	50
Gas Distribution	3	22
Telecom Duct	47	56
Total	168	302

Source - Polymer Association    CARG - 17%

Plastic Pipes are gaining ground faster now that their relative advantages/benefits/low carbon footprint/cost of ownership vis-à-vis traditional Metal/DI/Cement Piping are being  realized . Some of these factors are :

a). Green Product : Low embodied energy of raw-material, low energy consumption from production to transportation upto site, to in-service pumping energy (highest Hazen’s Williams C value of 150 , or lowest coefficient of friction, which is sustained over its service lifetime) – relevant to today’s times.(Figs. 5, 6 & 7). Moreover, the quality & potability of water is maintained in the inert PE Pipes as compared to metal pipes prone to corrosion & incrustations.

Fig. 5 PE Pipe after 50 Years and Fig. 6 Metal Pipe after 30-40 Years

Fig. 7 How London’s Victorian Water Mains Fig. 8 Monolithic Joint with Butt Fusion looked like; replaced with PE Pipes

1. Easy & Fast installation : The low weight and easy handling of Plastics Piping systems helps faster project execution leading to lower cost/time over-runs
2. Leak proof monolithic joint stronger than the Pipe itself : Globally proven record of lowest joint failures and lowest %age of NRW (Non-Revenue Water) (Fig. 9 ). Muncipalities are choosing PE Pipes to reduce water loss and provide 24 x7 water availability (eg. Karnataka, Nagpur, New Delhi, etc)
   Fig. 9 United Kingdom Water Mains National Failure Database
   
3. Lower cost of appurtenances : Ability to withstand higher water hammer or surge pressures
4. Lesser requirement of specials/bends : Unique cold bending radius property (20-25 times the diameter of Pipe) of PE Pipes leading to lower capital cost
5. Suitable for soil settlement/earthquake prone areas : PE Pipes are have flexibility and ability to take the contours of the most undulating of  terrains
6. Long service life of 100 years or so (for Pipe of proper quality, correct jointing and installation) .
   Fig. 10 PE Piping for underground Fire Hydrant
   
7. Highest abrasion resistance amongst Piping materials : Mining industry uses PE Piping for dewatering/slurry transport
8. Suitable for trenchless procedure , and HDD (Horizontal Directional Drilling) applications : CGD (upto 16 bars) & Telecom Networks invariably use PE Piping for  Gas conveyance and for carrying OFC. These Pipes are being laid by no-dig or trenchless procedures thereby preventing traffic/public disruption and inconvenience.
   Fig. 11 HDD or Trenchless Installation in Graphics
   
9. Excellent Chemical Resistance : Ideally suited for aggressive (alkaline / acidic) soils , Process Plants and Effluent discharge.
10. Ideally suited for Sewerage application : PE Pipes are inert to Sewer Gases such as H2S, etc. Crowns of Cement Pipes fail due to aggressive nature of sewerage
    Fig. 12 1200 mm PE Pipes for Sewerage Force/Pressure Mains in Delhi
    
11. Ideally suited for Sea/River water intake Piping, and marine outfalls : Unlike metal Pipes, PE Pipes do not corrode . Desalination Plants (SWRO, BWRO) across the world use only PE Piping.
    Fig. 13.  1600 mm PE Pipes for Sea Water Intake & Marine Outfall of a Desal Plant in S. India
    
12. No failures due to galvanic action in soil : No requirement of cathodic protection)
13. No protective internal/external linings required : As in DI Pipes and Cement Pipes
14. Low first cost  : At least upto 700-800 mm diameters , as compared to DI Piping
15. Lowest Life Cycle Cost (or Cost of Ownership)

The Challenge in Emerging/Developing Nations : With the fulcrum of global economy shifting eastwards, emerging economies such as India, China, Brazil, South Africa, ME, Malaysia, Indonesia, Vietnam , Phillipines, etc. are realizing the need to bring higher proportions of their population under Piped Water and Sanitation/Sewerage collection networks.

Moreover, the UN Millenium Developmental goals in Water and Sanitation are the reference points for the second rung of countries, such as those in Africa and elsewhere. An acute need to give entire people access to Water & Sanitation is being felt all across.

The major challenges facing some of these emerging, and yet to emerge economies, are the burgeoning populations , subjecting these countries  to environmental degradation (polluted rivers and water-bodies due to untreated sewer/waste water , drying underground aquifers due to over-drawing of water, sea water ingress in coastal areas , soil salinity, drying up of water bodies, deforestation, etc.), and consequently water stress.

Muncipal Corporations/Utility Bodies in India and other countries , have realized the need to control  non-revenue water (NRW - euphemism for water loss) and make their citizens sensitive to finite availability of potable water, and water conservation. PE Pipes are coming in handy to fulfill these objectives .

The challenge in Developed Countries : PE Pipes are seeing a resurgence of growth in developed world also due to the need of these countries to replace the old networks (come up progressively over the last 100 years or so) made with traditional Piping like metal (CI, GI, MS, etc) and cement pipes(RCC & AC Pipes).  Increased activity in Coal Seam Gas/Shale Gas generation, Desalination, Broadband Networks, Mining, etc. is also leading to increase in use of PE Piping materials at a much higher rate of growth than anytime in the past.