A method for mechanical property assessment across butt fusion welded polyethylene pipes

  • Slimane Niou
  • Kamel Chaoui
  • Salaheddine Azzouz
  • Nacira Hamlaoui
  • Latifa Alimi


The use of high-density polyethylene pipes in gas and water distribution networks is steadily growing worldwide. If the resistance of plain pipes is at present time well established using appropriately designed standards, welding issues continue to be globally approached equally in terms of structure and mechanical properties. Consequently, further practical investigations should be aimed at studying mechanical properties in the weld region which includes the melt zone and its heat-affected zones. This work presents a method based on removing layers in order to assess localized variances in mechanical properties throughout the weld seam in both radial and circumferential directions. An experimental plan based on specific machining operations allowed testing 39 standard specimens representing the weld volume matter in three concentric layers for given pipe dimensions and their counterpart standard unwelded ones. The typical stress–strain behavior of semi-crystalline materials is preserved in welded and unwelded specimens but with different characteristic limits. At the weld inner layers, properties such as elastic modulus, yield, and failure stresses displayed lower values, whereas in welded outer layers, the tendency is inversed. The cold drawing extend remained approximately steady for unwelded and welded cases across the pipe wall. This property is less affected by the presence of the weld as it described a constant material flow which is mostly a function of available material quantity for yielding. The approach developed in this study gives consistent indications on welding quality around the pipe weld and across the thickness. Accordingly, outermost and innermost welded layers may exhibit lower or even bad-quality welds as imperfections can concentrate stresses at the joint interface because of cold weld problems. Such method enabled detecting 23% of failures at the weld seam from outer and inner layers while the middle layer did not reveal any failure at the weld. The causes of this behavior are approached using crystallinity evolution in welded and unwelded pipes.


HDPE pipe Butt fusion welding Mechanical properties Radial direction Circumferential direction Structural variances 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.



The authors would like to express their gratitude to those who provided assistance to this research work: SARL Z.A.—Annaba (Water Construction Network Co.), Mechanical Eng. Dept. (Hall Technologique) of Guelma University (8 May 1945 U.), R&D Dept., POLYMED Co., Skikda, Unité de Recherche Matériaux, Procédés et Environnement (URMPE) of Boumerdes University (UMBB). Fruitful discussions with members of LR3MI of UBM Annaba are also greatly appreciated. Part of this work was supported by Algerian Ministry of Higher Education & Scientific Research, CNEPRU Research Project “Study of thermo-mechanical behavior of butt welded joints in HDPE pipes,” Project Code A11N01UN23012014122 (2014).


  1. 1.
    Wilson D, Filion Y, Moore I (2015) State-of-the-art review of water pipe failure prediction models and applicability to large-diameter mains. Urban Water J 14(2):173–184. CrossRefGoogle Scholar
  2. 2.
    Yu K, Morozov EV, Ashraf MA, Shankar K (2017) A review of the design and analysis of reinforced thermoplastic pipes for offshore applications. J Reinf Plast Compos.
  3. 3.
    Deblieck RAC, van Beek DJM, McCarthy M, Mindermann P, Remerie K, Langer B, Grellmann W (2017) A simple intrinsic measure for rapid crack propagation in bimodal polyethylene pipe grades validated by elastic–plastic fracture mechanics analysis of data from instrumented Charpy impact test. Polym Eng Sci 57:13–21. CrossRefGoogle Scholar
  4. 4.
    Sharma GVSS, Umamaheswara Rao R, Srinivasa Rao PS (2017) A Taguchi approach on optimal process control parameters for HDPE pipe extrusion process. J Ind Eng Int 13(2):215–228. CrossRefGoogle Scholar
  5. 5.
    Han L-H, Deng Y-H, Liu C-D (1999) The determination of JIC for polyethylene pipe using non-standard arc-shaped specimen. Int J Press Vessel Pip 76:647–651. CrossRefGoogle Scholar
  6. 6.
    van der Stok EJW, Scholten FL (2016) Determining the residual quality of PE pipes using the strain hardening test. Proc. of the 18th plastic pipes Conf. PPXVIII, September 12–14, 2016, Berlin, 10p.
  7. 7.
    Cherief MND, Elmeguenni M, Benguediab M (2017) Impact fracture toughness evaluation for high density polyethylene materials. J Appl Mech Tech Phys 58(2):335–341CrossRefGoogle Scholar
  8. 8.
    Akkurt A (2014) An analysis of electro-melting and hot element welding methods’ safety used to join PE natural gas pipes. Int J Mech Mechatron Eng 3(2):493–504MathSciNetGoogle Scholar
  9. 9.
    Saharudin MS, Atif R, Shyha I, Inam F (2016) The degradation of mechanical properties in polymer nano-composites exposed to liquid media (a review). RSC Adv 6:1076–1089. CrossRefGoogle Scholar
  10. 10.
    Hamlaoui N, Azzouz S, Chaoui K, Azari Z, Yallese MA (2017) Machining of tough polyethylene pipe material: surface roughness and cutting temperature optimization. Int J Adv Manuf Technol 92:2231–2245. CrossRefGoogle Scholar
  11. 11.
    Belhadi S, Kaddeche M, Chaoui K, Yallese MA (2016) Machining optimization of high density polyethylene pipe using the Taguchi method and grey relational analysis. Int Polym Process 31(4):491–502. CrossRefGoogle Scholar
  12. 12.
    Guo S-M, Yang Z-G, Tang X-Y, Zuo Y-T (2017) Safety assessment of high density polyethylene pipe with thermal damages. J. Plast Rubber Compos Macromol Eng 46(4):1743–2898. Google Scholar
  13. 13.
    Talhi FZ, Benaniba MT, Belhaneche-Bensemra N, Massardier V (2016) Comparison of material properties in butt welds of used and unused polyethylene pipes for natural gas distribution. J Polym Eng 37(3):279–285. Google Scholar
  14. 14.
    Mikula J, Hutař P, Nezbedová E, Lach R, Arbeiter F, Ševčík M, Pinter G, Grellmann W, Náhlíka L (2015) On crack propagation in the welded polyolefin pipes with and without the presence of weld beads. Mater Des 87:95–104. CrossRefGoogle Scholar
  15. 15.
    Vigier G, Degoulet C, Germain Y (2001) Physical and mechanical properties of polyethylene for pipes in relation to molecular architecture: I microstructure and crystallisation kinetics. Polymer 42:8425–8434CrossRefGoogle Scholar
  16. 16.
    Kiass N, Khelif R, Boulanouar L, Chaoui K (2004) Experimental approach to mechanical property variability through a high-density polyethylene gas pipe wall. J Appl Polym Sci 97:272–281. CrossRefGoogle Scholar
  17. 17.
    Pokharel P, Kim Y, Choi S (2016) Microstructure and mechanical properties of the butt joint in high density polyethylene pipe. Int J Polym Sci, Art. ID 6483295. 13p
  18. 18.
    Jagtap TU, Mandave HA (2015) Machining of plastics: a review. Int J Eng Res Gen Sci 3((2) (Part 2)):577–581Google Scholar
  19. 19.
    Alauddin M, Choudhury IA, Baradie MAE, Hashmi MSJ (1995) Plastics and their machining: a review. J Mater Process Technol 54:40–46. CrossRefGoogle Scholar
  20. 20.
    Rehab-Bekkouche S, Ghabeche W, Kaddeche M, Kiass N, Chaoui K (2009) Mechanical behaviour of machined polyethylene filaments subjected to aggressive chemical environments. Mechanika (MECHANICS) 77(3):40–46Google Scholar
  21. 21.
    Alimi L, Ghabeche W, Chaoui W, Chaoui K (2012) Étude des propriétés mécaniques à travers la paroi d’un tube HDPE-80 extrudé destiné à la distribution du gaz naturel. Matér Tech 100(1):79–86. CrossRefGoogle Scholar
  22. 22.
    Alimi L, Chaoui K, Ghabeche W, Chaoui W (2013) Short−term HDPE pipe degradation upon exposure to aggressive environments. Mater Tech 101:701. CrossRefGoogle Scholar
  23. 23.
    Ghabeche W, Alimi L, Chaoui K (2015) Degradation of plastic pipe surfaces in contact with an aggressive acidic environment. 30. Int. Conf. Technol. & Mater. for Renew. Energy, Envir. & Sustainability. Energy Procedia 74:351–364.
  24. 24.
    Kafieh R, Lotfi T, Amirfattahi R (2011) Automatic detection of defects on polyethylene pipe welding using thermal infrared imaging. Infrared Phys Technol 54(4):317–325CrossRefGoogle Scholar
  25. 25.
    Gueugnaut D, Tessier M, Bouaffre R, Lopitaux A (2017) Ultrasonic phased array inspection of electrofused joints implemented in polyethylene gas piping systems. J Mater Sci Eng A 7(3–4):68–81. Google Scholar
  26. 26.
    Galchun A, Korab N, Kondratenko V, Demchenko V, Shadrin A, Anistratenko V, Iurzhenko M (2015) Nanostructurization and thermal properties of polyethylenes’ welds. Nanoscale Res Lett 10:138. Springer Open Access, 6pCrossRefGoogle Scholar
  27. 27.
    Hehn O (2006) Analyse expérimentale et simulation thermomécanique du soudage bout à bout de tubes de polyéthylène. PhD Thesis, Ecole des Mines de Paris, 20pGoogle Scholar
  28. 28.
    Dai H, Peng J (2017) The effects of welded joint characteristics on its properties in HDPE thermal fusion welding. Mod Phys Lett B 31(15):1750185:1–11. CrossRefGoogle Scholar
  29. 29.
    Shaheer M, Troughton M, Khamsechnezad A, Song J (2017) A study of the micro-mechanical properties of butt fusion-welded joints in HDPE pipes using the nano-indentation technique. Weld World 61:819–831. CrossRefGoogle Scholar
  30. 30.
    BS ISO 4427–2 2007 British standard, Plastic piping system—polyethylene (PE) pipes and fittings for water supply—part 2: pipes;
  31. 31.
    ASTM Standard D 638–02a 2002 Standard test method for tensile properties of plastics (metric), Annual Book of ASTM StandardsGoogle Scholar
  32. 32.
  33. 33.
    ISO 12176–3 (2003) Plastics pipes and fittings—equipment for fusion jointing polyethylene systems—part 1: Butt fusionGoogle Scholar
  34. 34.
    Barber P, Atkinson JR (1974) The use of tensile tests to determine the optimum conditions for butt fusion welding certain grades of polyethylene, polybutene-I and polypropylene pipes. J Mater Sci 9:1456–1466CrossRefGoogle Scholar
  35. 35.
    de Courcy DR, Atkinson JR (1977) The use of tensile tests to determine the optimum conditions for butt welding polyethylene pipes of different melt flow index. J Mater Sci 12(8):1535–1551CrossRefGoogle Scholar
  36. 36.
    Kaddeche M, Chaoui K, Yallese MA (2012) Cutting parameters effects on the machining of two high density polyethylene pipes resins. Mech Ind 13:307–316. CrossRefGoogle Scholar
  37. 37.
    Niou S, Azzouz S, Chaoui K, Azari Z (2016) Développement d’une méthode pour caractériser la résistance mécanique circonférentielle d’un joint de tube plastique soudé bout-à-bout, 10èmes Journées de Mécanique (JM’10, EMP), Ecole Militaire Polytechnique, 12-13 April, Algiers, 1–5Google Scholar
  38. 38.
    Leskovics K, Kollár M, Bárczy P (2006) A study of structure and mechanical properties of welded joints in polyethylene pipes. Mater Sci Eng A 419:138–143. CrossRefGoogle Scholar
  39. 39.
    Lee B-Y, Kim J-S, Lee S-Y, Kim YK (2012) Butt-welding technology for double walled polyethylene pipe. Mater Des 35:626–632CrossRefGoogle Scholar
  40. 40.
    Tariq F, Nausheen Naz N, Khan MA, Baloch RA (2012) Failure analysis of high density polyethylene butt weld joint. J Fail Anal Prev 12:168–180. CrossRefGoogle Scholar
  41. 41.
    El-Bagory TMAA, Younan MYA, Sallam HEM (2013) Mechanical behavior of welded and un-welded polyethylene pipe materials, K-PVP Conference, Proc. of the ASME, Pressure Vessel & Piping Division, Paper # 2013–97743, Paris, (14–18/07/13)Google Scholar
  42. 42.
    Lai HS, Kil SH, Yoon KB (2015) Effects of defect size on failure of butt fusion welded MDPE pipe under tension. J Mech Sci Technol 29(5):1973–1980. CrossRefGoogle Scholar
  43. 43.
    Zhao JQ, Daigle L, Beaulieu D (2002) Effect of joint contamination on the quality of butt-fused HDPE pipe joints. Can J Civ Eng 29(5):787–798. CrossRefGoogle Scholar
  44. 44.
    Atkinson JR, Barber P (1972) Some microstructural features of the welds in butt-welded polyethylene and polybutene-1 pipes. J Mater Sci 7:1131–1136CrossRefGoogle Scholar
  45. 45.
    Qi F, Huo L, Zhang Y, Jing H (2004) Study on fracture properties of high-density polyethylene (HDPE) pipe. Key Eng Mater 261-263:153–158. CrossRefGoogle Scholar

Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2018

Authors and Affiliations

  • Slimane Niou
    • 1
  • Kamel Chaoui
    • 1
  • Salaheddine Azzouz
    • 2
  • Nacira Hamlaoui
    • 3
  • Latifa Alimi
    • 4
  1. 1.Mechanics of Materials and Plant Maintenance Research Laboratory (LR3MI), Mechanical Engineering Department, Faculty of EngineeringBadji Mokhtar University of Annaba (UBMA)AnnabaAlgeria
  2. 2.LR3MI, Ecole Supérieure des Technologies Industrielles (ESTI)AnnabaAlgeria
  3. 3.LR3MI, Mechanical Engineering Department, Faculty of Sciences and Technology8 May 1945 University of GuelmaGuelmaAlgeria
  4. 4.LR3MI, Centre de Recherche en Technologies Industrielles (CRTI)ChéragaAlgeria

Personalised recommendations