Over the past decade, Australia’s water utilities have become increasingly reliant on trenchless methods of pipeline installation and rehabilitation. This trend has in turn resulted in a demand for higher performance, long-life polyethylene pipes that will provide reliable service for 100 years or more.
It is this requirement that motivated Iplex to look toward the evolution of PE100 pipe materials – materials that can withstand the inevitable damage and abuse that will occur in trenchless directionally drilled, slip lined and pipe burst installations, or even in open trench installations, where undetected rock impingement may occur during construction.
For the past five years Iplex has collaborated with Australia’s resin manufacturer Qenos to develop a superior PE100 resin; a resin with exceptional resistance to slow crack growth. The product of this research and testing program is Iplex Millennium®.
Iplex Millennium is a high stress crack resistant (HSCR) grade of PE100 pipe that provides up to ten times greater resistance to slow crack growth than conventional PE100 pipe. It has the same pressure burst strength of conventional PE100 pipe, but is specifically designed for use in critical or high value pipeline assets where the risk of premature failure from slow crack growth is possible.
Iplex Millennium conforms in all respects with AS/NZS 4130. The Plastics Industry Pipe Association (PIPA) has published guideline POP016 establishing the performance requirements of HSCR PE100 pipe resin and the Water Service Association of Australia (WSAA) has appraised Millennium in report 1610.
Under certain circumstances, selecting Iplex Millennium over conventional PE100 will permit a reduction in pipe wall thickness, resulting in substantial installation and pump energy cost savings.
The high stress crack resistance of Iplex’s Millennium pipe may also allow the use of excavated spoil, eliminating the need to import granular embedment in open trench applications. This can save a contractor up to 20 per cent in pipeline construction costs.
Another advantage is increased service life expectation, as Iplex Millennium pipe can easily achieve an anticipated service life of 100 years due to its greater tolerance of surface damage. This is a substantial benefit to pipeline owners who are required to make accounting provisions for the replacement of assets.
Millennium can also provide safer gas pipelines where ‘squeeze-off’ is used to manage pipeline flows for planned or emergency maintenance, and it increases resistance to the initiation of slow crack growth wherever these stress concentrators are present, leading to a longer service life and enhanced network dependability.
The first Australian HDD installation of Iplex Millennium is currently underway near Yeppoon in Queensland. The Livingstone Shire Council is drilling beneath an environmentally sensitive estuary to provide an increased flow capacity to meet population growth, in a region south of Causeway Lake.
The project involves two 400 metre long bores to install parallel DN450 and DN315 pipes. At the time of writing, the DN450 pipe had been drilled and pulled into place with the DN315 to follow shortly.
The critical importance of the pipeline, combined with difficult ground conditions that include significant amounts of rock, drove Livingstone Shire Council to select Iplex Millennium pipe and entrusted specialist HDD contractor Maxibor with the installation.
Livingstone Shire Council’s Causeway Lake water main replacement project marks a breakthrough for the Australian trenchless pipeline industry by establishing a new benchmark in the standard of PE100 polyethylene pipe.
This partner content is brought to you by Iplex Pipelines Australia. For more information, visit www.iplex.com.au.