19/02/2009

PE-X Pipes - ‘Flying’ Infrastructure Innovation

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PE-X Pipes - ‘Flying’ Infrastructure Innovation

A sewage PEX pipeline, laid by helicopter across a harsh and rocky nature reserve, was made from cross-linked HDPE (PEX) pipes, using the extremely pure Lupolen 5261Z Q456 resin in the cross-linking process. This case demonstrates how the toughness and versatility of PEX pipes can deliver time and cost savings in infrastructure projects.

When the city of Karmiel in northern Israel needed to make a connection to its sewage system, the only feasible route lay across the mountainous terrain of a nature reserve south of the city.

PE-X Pipes - Flying Infrastructure Innovation

A bold solution

Golan Plastics, Israel’s largest manufacturer of plastic products for the building sector, manufactures cross-linked HDPE (PEX) pipes with the brand name PEXGOL. Golan proposed a bold solution: a 280 mm pipeline in PEXGOL laid by helicopter directly on the rocky terrain. "PEXGOL was the only alternative to steel and much less costly," explained Eng. Yosi Bar, Golan Plastic’s R&D manager. "Given the harsh nature of the site and the unusual laying method, PEXGOL’s resistance to stress cracking, abrasion and extremes of temperature were critical to the success of the project."

"We are the only company in the world making PEX pipe sections in such large diameters – our maximum is 500 mm – so this project was well within our capabilities."

High purity, high MW

LyondellBasell and its predecessor companies have been supplying Golan plastics with PE resins for over 30 years. For this project they provided an extremely pure high molecular weight resin, Lupolen 5261 Z Q 456. "Golan carried out the cross-linking itself," explained Dr Hansjörg Nitz of LyondellBasell’s PSC business unit, business development Engineer. "We provided them with extremely pure base resins, allowing them to use the minimum amount of peroxide for the cross-linking process, which optimizes the properties of the final product."

All in a morning’s work

The 55-metre flanged pipe sections were airlifted to the site by helicopter. A four-man team on the ground received the sections and made the necessary connections. The whole laying operation was completed in just four hours. "This project would have taken several days using other materials and techniques," pointed out Yosi Bar. "It’s a clear demonstration of the time and cost savings that the toughness and versatility of PEX materials can deliver in infrastructure projects."

Lupolen PE-X grades

Thirty years of service for a demanding industry. For 30 years, LyondellBasell’s Lupolen HDPE resins used in the production of PE-X pipes have been widely used by customers in plumbing and heating applications. Key high-performance products from LyondellBasell’s portfolio include:

  • Lupolen 5261 Z Q 456 (PE-Xa)
  • Lupolen 5031 L Q 449 (PE-Xb)
  • Lupolen 4261 A Q 416 (PE-Xc)

Lupolen 5261 Z Q 456 (PE-Xa) resins are also used in special large-diameters applications (up to 500 mm) such as:

  • critical drinking water applications
  • transport of chemical substances
  • sewage pipes

In such demanding applications, customer reports indicate that piping products based on Lupolen PE-X resins offer the following advantages:

  • Excellent resistance to internal creep rupture strength at elevated temperatures
  • Resistance to slow and rapid crack propagation
  • Chemical and abrasion resistance
  • Easy installation without sand bedding