Papers
Plastic Pipes Conference Association # 2012 Barcelona
Andreas Frank, Gerald Pinter, Mridula Kapur, E. Nezbedová
Results from cracked round bar tests (CRB) and pennsylvania notch tests (PENT) for several polyethylene (PE) pipe grades are compared. The CRB tests were conducted at 23 °C and 80 °C, the PENT tests only at 80 °C. A material ranking based on the CRB tests was in good accordance to PENT failure times, although a slight temperature dependence of the ranking could be identified. If using adequate instruments for measuring the crack opening displacement the clear detection of the crack initiation in the CRB tests opens the possibility of partitioning the total failure time into time for crack initiation and time for slow crack growth which potentially may be interesting for material development or conservative lifetime assessment of pressurized PE pipes.
Related papers
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Author(s) : Gerald Pinter, Johannes Wiener, Florian Arbeiter, Abhishek Tiwari, Otmar Kolednik
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Accelerated aging experiments by the immersion of a commercial polyethylene (PE) pipe grade in 10 ppm of chlorine dioxide (ClO2) and in 100 ppm of hypochlorite (HOCl) solution at 60 °C were performed. An additional immersion test was conducted in 1 ppm of ClO2 at 40 °C. The exposure parameters were continuously...
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Author(s) : Isabelle J. Berger, Andreas Frank, Gerald Pinter, David Nitsche, Dirk Petry
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Author(s) : Pavel Hutar, Jan Poduska, Pavol Dlhy, Andreas Frank, Jaroslav Kucera, Jiri Sadilek, Gerald Pinter, Lubos Nahlik
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In order to improve the circular economy of polymers in terms of sustainability and reduced carbon footprint, the increased use of recyclates has become a topic of major importance. Due to their long design lifetimes, pipe applications represent an excellent opportunity to create added value to non-virgin polymers. In...
Author(s) : Juergen Wuest, Mirko Wenzel, Andreas Bilsing, Peter Postma, Werner Wessing
Within the scope of a DVGW (German Technical and Scientific Association for Gas and Water) research project the technology of squeezing-off for PE pipes at operating pressures higher than 1 bar and the extension to new materials with higher operating pressures were investigated. For this purpose the tightness of the...
Author(s) : Lonnie Corley, Dane Chang, Harvey Svetlik, Matt Brandes, Thomas Musto, Frank Schaaf, David Fink
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Author(s) : Amaia Bastero, Márton Bredács, Andreas Frank
The effect of chlorinated water environment to plastic pipes has been intensively investigated in recent years and proved to affect the lifetime of plastic pipes. Since it is known that the use of the different disinfectants (ClO2, HClO/ClO- ) imply different degradation rates, understanding the conditions...
Author(s) : G. Pinter, F. Arbeiter, A. Frank
The cyclic cracked round bar test has recently been added as a full-fledged ISO standard (ISO 18489) for comparison of polyethylene pipe grade materials’ slow crack growth resistance. However, possibilities of this test are yet far from being exhausted. Seeing, that polyethylene is only used in approximately 30% of...
Author(s) : Márton Bredács, Anita Redhead, Andreas Frank, Amaia Bastero, Gerald Pinter
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Author(s) : Andreas Frank, Isabelle J. Berger, Florian Arbeiter, Pavel Hutař, Gerald Pinter
Due to the high slow crack growth resistance of modern polyethylene pipe grades a reliable lifetime assessment of pipes with focus on stage II failure has become challenging. The current paper presents a scientific approach for a fracture mechanics lifetime prediction based on Cyclic Cracked Round Bar (CRB) Tests....
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