0433851 - ÚFM 2015 RIV GB eng J - Článek v odborném periodiku
Poduška, Jan - Kučera, J. - Hutař, Pavel - Ševčík, Martin - Křivánek, J. - Sadílek, J. - Náhlík, Luboš
Residual stress distribution in extruded polypropylene pipes.
Polymer Testing. Roč. 2014, č. 40 (2014), s. 88-98. ISSN 0142-9418. E-ISSN 1873-2348
Grant CEP: GA ČR(CZ) GAP108/12/1560
Institucionální podpora: RVO:68081723
Klíčová slova: polypropylene * extruded polymer pipe * residual stress * curved beam methodology * numerical simulations
Kód oboru RIV: JL - Únava materiálu a lomová mechanika
Impakt faktor: 2.240, rok: 2014 ; AIS: 0.543, rok: 2014
Web výsledku:
http://www.sciencedirect.com/science/article/pii/S0142941814001809DOI: https://doi.org/10.1016/j.polymertesting.2014.08.006

This paper deals with the experimental determination of residual stress and other inherent properties, density, yield stress, specific enthalpy of fusion and melting point temperature, of a polypropylene grade for pipe applications. The most important of these characteristics is the residual hoop (circumferential) stress, because it has a considerable effect on pipe lifetime. The experimental procedure for obtaining the residual hoop stress distribution by measuring the deflection of axially slit ring specimens is described and the data are evaluated by two approaches e a method based on theory of a curved beam and an older method based on theory of a thick-walled cylinder. Numerical modelling by FEM is employed to simulate the behavior of the ring specimens. The experiment was carried out on a set of 8 polypropylene pipes of different dimensions. The results for these pipes are compared, and a general equation describing the residual hoop stress distribution independently of pipe dimensions is proposed. Also, the influence of axial residual stress on the hoop residual stress is studied and, with the help of FEM, a correction of he results for long pipes is derived.
Trvalý link: http://hdl.handle.net/11104/0238685