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
Author(s) : Andreas Moerman, Flip van der Valk, Mirjam Blokker KWR, Tjakko Haaijer, Jan Vreeburg,
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Author(s) : Gerald Pinter, Johannes Wiener, Florian Arbeiter, Abhishek Tiwari, Otmar Kolednik
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Author(s) : Lukas Travnicek, Pavel Hutar, Jan Poduska, Andreas Frank, Florian Arbeiter, Jaroslav Kucera, Jiri Sadilek, Gerald Pinter, Lubos Nahlik
The application of recycled material in pressure piping systems has been considered lately – it was suggested, that the recycled polyethylene could be used as a part of a multilayer pipe together with virgin material. This type of pressure pipes is not availableon the market yet, so their properties can be only...
Author(s) : Andreas Frank, Mario Messiha, Günter Dreiling, Norbert Schuler, Jens-Martin Storheil, Erwin Mayrbäurl, Stuart Ramella, Frank Krause, Rudi Berning, Philippe Gabriëls, Alpay Aydemir, Thomas Koch, Florian Arbeiter, Gerald Pinter
The Cyclic Cracked Round Bar (CRB) Test has been applied to study the slow crack growth (SCG) resistance of virgin, recycled, and reprocessed PVC-U. This fracture mechanical test allows a quick ranking of the SCG resistance of PVC-U. A clear correlation between the K-value and the SCG resistance has been elaborated....
Author(s) : Karel van Laarhoven, Andreas Moerman
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Author(s) : Hermann van Laak, Jan Heimink, Mario Messiha, Andreas Frank, Christoph Bruckner, Thomas Kratochvilla
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Author(s) : Márton Bredács, Andreas Frank, Amaia Bastero, Alex Stolarz, Gerald Pinter
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...
Author(s) : Gerald Pinter, Florian Arbeiter, Johannes Wiener, Andreas Frank, Otmar Kolednik
In order to further increase the fracture toughness of pipes, biomimetic layer design of the pipe wall can be used. Therein, soft polymer interlayers can act as crack-arresters in a matrix of stiffer and inherently more brittle polymers. The effectiveness of the crack arresting role of soft interlayers in a...
Author(s) : Mario Messiha, Andreas Frank, Isabelle J. Berger, Jan Heimink, Hermann van Laak, Florian Arbeiter, Gerald Pinter
Since the last decade polyamide 12 (PA12) has been successfully introduced as material for SDR 11 gas piping systems up to 18 bar, representing itself as an attractive alternative to steel pipes for high-pressure applications. Practical experience has confirmed that beside the higher strength, PA12 pipe grades ...
Author(s) : Isabelle J. Berger, Andreas Frank, Gerald Pinter, David Nitsche, Dirk Petry
Electrofusion (EF) sockets constitute a well-established and practically proven technology for the joining of polyethylene (PE) pressure pipes. As for the pipes, the potential lifetime of such welding connections is beside other properties also depending on the resistance against slow crack growth (SCG). The current...
Author(s) : Pavel Hutar, Jan Poduska, Pavol Dlhy, Andreas Frank, Jaroslav Kucera, Jiri Sadilek, Gerald Pinter, Lubos Nahlik
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Author(s) : Juergen Wuest, Benjamin Baudrit, Frank Dorbath, Christopher Pommer
A testing apparatus for determining the mechanical properties of electrofusion and heated tool sleeve welded joints with the mechanized linear shear test (LST) was developed. The LST-apparatus allows the recording of the force as a function of the extension / shear length. It has been proved that the linear shear...
Author(s) : Andreas Frank, Isabelle J. Berger, Mario Messiha, Carl-Gustaf Ek, Norbert Schuler, Jens-Martin Storheil, Erwin Mayrbäurl, Steve Heeley, Frank Krause, Lodewijk Niemöller, Philippe Gabriëls, Yogesh S. Deshmukh, Florian Arbeiter, Thomas Koch, Gerald Pinter
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....
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
This paper presents a brief overview of a challenging project at the Callaway Nuclear Power Plant where HDPE was utilized to replace degraded steel buried piping in a Safety Related water system. Callaway was the first Nuclear Power plant to obtain NRC approval and successfully place the HDPE piping system into...
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
To maintain the high quality of potable water chlorine based disinfectants are frequently dosed into the drinking water network. Considering the oxidative nature of these species their long-term impact on the aging of polyolefin pipes is a matter of interest. In this study four polyolefin pipe grades were objected to...
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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