Home Comparison of material properties in butt welds of used and unused polyethylene pipes for natural gas distribution
Article
Licensed
Unlicensed Requires Authentication

Comparison of material properties in butt welds of used and unused polyethylene pipes for natural gas distribution

  • Fatima Zohra Talhi EMAIL logo , Mohamed Tahar Benaniba , Naima Belhaneche-Bensemra and Valérie Massardier
Published/Copyright: July 13, 2016
Become an author with De Gruyter Brill

Abstract

The main purpose of this work was to evaluate the long term performance of butt welded polyethylene (PE) pipes in comparison to non-welded counterparts. Therefore, old welded PE pipes with different ages that had been used in Algerian gas distribution systems for up to 30 years were investigated. Samples prepared by butt welding of unaged pipes were used as reference. Crystallinity, melt rheology and thermal stability of pipes materials were examined at the weld zone and at the pipe wall. In order to assess the mechanical strength of welds, tensile test was conducted on both welded and unwelded specimens and the results of the strain to failure were considered for the determination of the weld factor. Compared to the reference, the results revealed that the crystallinity of PE materials at the weld zone was not affected by ageing as at the pipe wall. However, a slight decrease of the melt viscosity was observed for both welded and non-welded samples. The welds were found to be more sensitive to thermal and oxidative degradation than the parent pipes while the remaining amount of antioxidants was sufficient for service continuation. The tensile results indicate that welds strength were almost unaffected by ageing.

References

[1] Akkurt A. Int. J. Electron 2014, 3, 493–504.Search in Google Scholar

[2] Troughton MJ. Handbook of Plastics Joining: A Practical Guide, 2nd ed., William Andrew Inc.: Norwich, 2008.Search in Google Scholar

[3] Leskovics K, Kollar M, Barczy P. Mater. Sci. Eng. 2006, A419, 138–143.10.1016/j.msea.2005.12.019Search in Google Scholar

[4] Lu Y, Shinozaki DM, Herbert S. J. Appl. Polym. Sci. 2002, 86, 43–52.10.1002/app.10895Search in Google Scholar

[5] Mikula J, Hutar P, Nezbedova E, Lach R, Arbeiter F, Sevcik M, Pinter G, Grellmann W, Nahlik L. Mater. Des. 2015, 87, 95–104.10.1016/j.matdes.2015.07.131Search in Google Scholar

[6] Nishimura H, Narisawa I. Polymer 1991, 32, 2199–2204.10.1016/0032-3861(91)90046-LSearch in Google Scholar

[7] Chen H. J. Mater. Sci. Lett. 1997, 16, 897–898.10.1023/A:1018579903455Search in Google Scholar

[8] Chen H, Scavuzzo RJ, Srivatsan TS. J. Mater. Sci. Eng. Perform. 1997, 6, 473–480.10.1007/s11665-997-0119-8Search in Google Scholar

[9] Popelar SF, Popelar CH, Kenner VH. Int. J. Fracture 1991, 50, 115–130.10.1007/BF00035207Search in Google Scholar

[10] Sevcik M, Hutar P, Nahlik L. Mech. Compos. Mater. 2011, 47, 263–270.10.1007/s11029-011-9206-xSearch in Google Scholar

[11] Sevcik M, Hutar P, Nahlik L, Lach R, Knesl Z, Grellmann W. Int. J. Struct. Integr. 2012, 3, 148–157.10.1108/17579861211235174Search in Google Scholar

[12] Frank A, Pinter G, Lang RW. Polym. Test. 2009, 28, 737–745.10.1016/j.polymertesting.2009.06.004Search in Google Scholar

[13] Schulte U, Hessel J. 3R Int. 2006, 45, 482–485.10.1111/j.1365-4632.2005.02618.xSearch in Google Scholar

[14] Welding of Thermoplastics-Heat Tool Welding of Pipes, Pipeline Components and Sheets made of PE-HD, DVS 2207-1, DIN Deutsches Institut für Normung e. V., Berlin, Germany, 2005.Search in Google Scholar

[15] Barber P, Atkinson JR. J. Mater. Sci., 1974, 9, 1456–1466.10.1007/BF00552931Search in Google Scholar

[16] El-Bagory TMAA, Younan MYA, Sallam HEM. Mechanical Behavior of Welded and Un-welded Polyethylene Pipe Materials. Pressure Vessels and Piping Conference, Paris, French, 14–18 July 2013.10.1115/PVP2013-97743Search in Google Scholar

[17] DeCourcy DR, Atkinson JR. J. Mater. Sci. 1977, 12, 1535–1551.10.1007/BF00542804Search in Google Scholar

[18] Zhao JQ, Daigle L, Beaulieu D. Can. J. Civil. Eng. 2002, 29, 787–798.10.1139/l02-078Search in Google Scholar

[19] Hehn MO. Analyse experimentale et simulation thermomecanique du soudage bout à bout de tubes de polyethylene, PhD Thesis. Ecole des Mines de Paris, French, 2006, 45–47.Search in Google Scholar

[20] Fayolle B, Colin X, Audouin L, Verdu J. Polym. Degrad. Stab. 2007, 92, 231–238.10.1016/j.polymdegradstab.2006.11.012Search in Google Scholar

[21] Costa L, Luda MP, Trossarelli L. Polym. Degrad. Stab. 1997, 58, 41–54.10.1016/S0141-3910(97)00010-4Search in Google Scholar

[22] Allen NS, Palmar SJ, Marshall GP, Luc-Gardette J. Polym. Degrad. Stab. 1997, 56, 265–274.10.1016/S0141-3910(96)00148-6Search in Google Scholar

[23] Tireau J. Propriétés à long terme des gaines de polyéthylène haute densité utilisées pour les ponts à haubans, PhD Thesis. École Nationale Supérieure d'Arts et Métiers, French, 2011, 232–238.Search in Google Scholar

[24] Buried Polyethylene (PE) Pipes for the Supply of Gaseous of Fuels-Metric Series-Specifications, ISO4437, International Organization for Standardization, Geneva, Switzerland, 2007.Search in Google Scholar

Received: 2016-1-23
Accepted: 2016-5-26
Published Online: 2016-7-13
Published in Print: 2017-3-1

©2017 Walter de Gruyter GmbH, Berlin/Boston

Downloaded on 3.12.2025 from https://www.degruyterbrill.com/document/doi/10.1515/polyeng-2016-0015/html?lang=en
Scroll to top button