Influence of Different Welding Conditions of Polyolefin Pipes on Creep Crack Growth

  • J. Mikula
  • P. Hutař
  • M. Ševčík
  • E. Nezbedová
  • R. Lach
  • W. Grellmann
  • L. Náhlík
Part of the Springer Series in Materials Science book series (SSMATERIALS, volume 247)


The main aim of the paper is to study the influence of both material inhomogeneity and weld bead geometry on crack propagation in welded polyolefin pipes. Lifetime of three pipes welded by different welding procedures is numerically estimated. Experimentally observed shapes of weld bead and change of material properties inside the welded region (the change of Young’s modulus) is implemented into the numerical model of welded pipes. Circumferential crack is of interest during the crack propagation through the pipe wall and the stress intensity factor is evaluated. It is shown that the deformation of welded region plays an important role whatever it is caused by, either the inhomogeneous distribution of Young’s modulus or the amount of material in that region. The change of weld bead notch radius is not proved to be important for slow crack growth. It is shown that non-optimal welds can significantly decrease lifetime of pipe systems. The results of this research can be used for lifetime estimation and prediction of creep crack growth and further optimisation of welding conditions and butt weld technology.



This research was supported by German Research Foundation (DFG) by grant No. GR 1141/30-1, 31-1 and 32-1. Research team was also supported by the Ministry of Education, Youth and Sports of the Czech Republic throughout the project No. CZ.1.07/2.3.00/30.0063 “Talented postdocs for scientific excellence in physics of materials” and by CEITEC—Central European Institute of Technology with research infrastructure supported by the project CZ.1.05/1.1.00/02.0068 financed from European Regional Development Fund.


  1. 1.
    Janson, L.-E.: Plastic Pipes for Water Supply and Sewage Disposal. Magnestams Reklam/Christensons Grafika AB, Stockholm (1989)Google Scholar
  2. 2.
    Lu, X., Brown, N.: A test for slow crack growth failure in polyethylene under a constant load. Polym. Test. 11, 309–319 (1992)CrossRefGoogle Scholar
  3. 3.
    Lang, R. W., Pinter, G., Balika, W., Haager, M.: A Novel qualification concept for lifetime and safety assessment of PE pressure pipes for arbitrary installation conditions. In: Proceedings of Plastics Pipes XIII (Washington, 02.–05.10.2006). Washington (2006), pp. 1–10Google Scholar
  4. 4.
    Frank, A., Freimann, W., Pinter, G., Lang, R.W.: A fracture mechanics concept for the accelerated characterization of creep crack growth in PE-HD pipe grades. Eng. Fract. Mech. 76, 2780–2787 (2009)CrossRefGoogle Scholar
  5. 5.
    Hutař, P., Ševčík, M., Náhlík, L., Pinter, G., Frank, A., Mitev, I.: A numerical methodology for lifetime estimation of HDPE pressure pipes. Eng. Fract. Mech. 78, 3049–3058 (2011)CrossRefGoogle Scholar
  6. 6.
    ISO 21307 (2011): Plastics pipes and fittings—Butt fusion jointing procedures for polyethylene (PE) pipes and fittings used in the construction of gas and water distribution systemsGoogle Scholar
  7. 7.
    Veselý, P., Kotter, I., Lach, R., Nezbedová, E., Knésl, Z., Hutař, P., Grellmann, W.: Prüfmethoden zur Analyse des lokalen mechanischen Verhaltens von Schweißnähten in Polyethylen-Kunststoffrohren. In: Borsutzki, M., Geisler, S. (Eds.): Fortschritte der Kennwertermittlung für Forschung und Praxis (Proceedings Werkstoffprüfung 2009, Bad Neuenahr, 03.–04.12.2009). Verlag Stahleisen, Düsseldorf (2009), pp. 371–376Google Scholar
  8. 8.
    Lach, R., Hutař, P., Veselý, P., Nezbedová, E., Knésl, Z., Grellmann, W.: Structural changes, evolution of damage parameters and crack propagation behaviour in welded plastic pipes. Key Eng. Mater. 465, 427–430 (2011)CrossRefGoogle Scholar
  9. 9.
    Mikula, J., Ševčík, M., Hutař, P., Náhlík, L.: Fracture mechanics assessment of cracked welded polyolefin pipes. In: Proceedings of Engineering Mechanics 2014 (Svratka, 12.–15.05.2014). Svratka (2014), pp. 396–399Google Scholar
  10. 10.
    Florian, A., Pinter, G., Frank, A.: Impact of single and dual pressure butt-welding procedures on the reliability of PE 100 pipe welds. In: Proceedings of EUROTEC 2013 (Lyon, 04.–05. 07. 2013). Lyon (2013), pp. 136–141Google Scholar
  11. 11.
    Chan, S., Tuba, S., Wilson, W.: On the finite element method in linear fracture mechanics. Eng. Fract. Mech. 2, 1–17 (1970)CrossRefGoogle Scholar
  12. 12.
    Anderson, T.L.: Fracture Mechanics: Fundamentals and Application. CRC Press, Boca Raton (1991)Google Scholar
  13. 13.
    Frank, A., Hutař, P., Pinter, G.: Numerical assessment of PE 80 and PE 100 pipe lifetime based on Paris-Erdogan equation. Macromol. Symp. 311, 112–121 (2012)CrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • J. Mikula
    • 1
    • 2
  • P. Hutař
    • 1
  • M. Ševčík
    • 1
  • E. Nezbedová
    • 3
  • R. Lach
    • 4
  • W. Grellmann
    • 4
    • 5
  • L. Náhlík
    • 1
  1. 1.Institute of Physics of MaterialsAcademy of Sciences of the Czech RepublicBrnoCzech Republic
  2. 2.Brno University of TechnologyBrnoCzech Republic
  3. 3.Polymer Institute BrnoBrnoCzech Republic
  4. 4.Polymer Service GmbH Merseburg, Associated An-Institute of University of Applied Sciences MerseburgMerseburgGermany
  5. 5.Centre of EngineeringMartin Luther University Halle-WittenbergHalle/SaaleGermany

Personalised recommendations