Posters - Additional Information
Plastic Pipes Conference Association # 2001 Munich
Scholten, Gueugnaut, Berthier
Detergents of the type nonylphenol ethoxylate (NPE) are often used in PE pipe tests at 80°C like the Full Notch Creep Test, Cone test and Constant Load test. However, evidence is presented that this class of detergents is very vulnerable to oxidation by oxygen from the air surrounding the tests baths. This leads to a lower concentration of active detergent and hence to unreliable failure times and failure rates. Although excluding oxygen from the tests baths can stop this oxidation, effective protective chemicals like antioxidants are not available. Moreover, discussions about environmental problems caused by metabolites of NPE detergents in the aquatic environment have caused a very large reduction in the use of these substances. They may become less readily available in future. An alternative detergent TeepolTM is presented which shows a constant activity in Cone tests on PE pipe materials during more than 1600 hours at 80°C. Consequently this detergent is recommended for use in FNC, constant load and Cone tests. A discussion in standardisation committees involved in these types of tests is proposed.
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A test program was carried out on two Polyamide resins, Polyamide 11 (PA11) and Polyamide 12 (PA12), both certified for gas networks. Polyamide’s advantage lies in its implementation, similar to that of polyethylene, and its properties allowing it to operate at up to 18 bar for gas, all other conditions being equal....
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Author(s) : Dominique GUEUGNAUT, Manuel TESSIER, Romuald BOUAFFRE
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Author(s) : Dominique GUEUGNAUT, Adil BOUJLAL, Aymeric LOPITAUX, Bertrand SEVRE
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Author(s) : Ernst van der Stok, Frans Scholten
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Author(s) : Frans Scholten, Ernst van der Stok
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Author(s) : Dominique GUEUGNAUT, Charles FERNANDEZ, Romuald BOUAFFRE, Bertrand SEVRE, Florent ANGELINI
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Author(s) : Frans Scholten
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Author(s) : Ernst van der Stok, Frans Scholten
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Author(s) : GUEUGNAUT Dominique, ANGELINI Florent, BOUJLAL Adil, BOUAFFRE Romuald, SEVRE Bertrand, LOUET Patrick
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Author(s) : Chebbo Z., Boujlal A., Gueugnaut D., Vincent M., Tillier Y.
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Author(s) : Gueugnaut Dominique, Boujlal Adil, Rousselot Denise, Bouaffre Romuald
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Author(s) : Van der Stok, Scholten
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Author(s) : Gueugnaut Dominique
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