Assessing the remaining service lifetime of PE pipes: an australian case study

Author(s) : Steven Folkman

A recent survey again confirms that PVC pipe has the lowest break rate when compared with break rates of ductile and cast iron, asbestos cement, steel, and concrete pipe. Other results of interest to water utilities and engineers are discussed. During 2017, Utah State University conducted a survey of utilities across...

Author(s) : Dominique GUEUGNAUT, Manuel TESSIER, Romuald BOUAFFRE

Given the virtual absence of available up-to-date results regarding the acceptance criteria for defects at electro-welding interfaces, a study has been launched by GRTgaz RICE with the two-fold aim of confirming the accuracy of the PAUT technique for the detection and sizing of calibrated pit-shaped defects implanted...

Author(s) : Márton Bredács, Andreas Frank, Amaia Bastero, Alex Stolarz, Gerald Pinter

Accelerated aging experiments by the immersion of a commercial polyethylene (PE) pipe grade in 10 ppm of chlorine dioxide (ClO2) and in 100 ppm of hypochlorite (HOCl) solution at 60 °C were performed. An additional immersion test was conducted in 1 ppm of ClO2 at 40 °C. The exposure parameters were continuously...

Author(s) : Ignacio Muñoz

During the last years PVC-O has become a popular product in pipe business due to the huge improvements of mechanical properties of PVC after orientation. At the same time, CPVC has become an important choice for hot water conduits in in-house applications. Molecor has started a research program to evaluate the...

Author(s) : Markus Gall, Reinhold W. Lang, Joerg Fischer, Ansgar Niehoff, Steven Schmidt

Despite recent efforts in promoting the utilization of recycled polymeric materials for more diverse and more advanced applications, there are still significant knowledge gaps with regards to the applicability of certain recyclate types for specific “re-use” purposes. When it comes to pipe applications, for instance,...

Author(s) : Anders Andtbacka, Frans Alferink, Peter Sejersen

The behavior of buried plastic pipes is already well described in standards and technical specifications and as well as proven in real life conditions. Plastics pipes in diameters up to around 400 mm are already in use for more than 60 years and pipes with larger diameters for more than 20 years now. All with good...

Author(s) : Ernest Lever

Six different polyethylene materials were tested using Cyclic Pressure Fatigue (CPF) as the accelerating process to correlate the results to conventional long-term hydrostatic test results that were previously developed as part of the material qualification process. The designation of the materials was unknown to the...

Author(s) : Ryosuke Nagahisa, Shinichi Katoh

We investigated the possibility of using a greaseless polyethylene (PE) ball valve by applying a coating on it to improve the valve’s robustness. In order to verify the valve’s operability, we performed initial-operating-torque, abrasion, and dust tests on both grease-applied and coatingapplied ball valves. These...

Author(s) : Davidovski Zoran

To get a deeper insight in why plastic pipes systems in some cases are deselected by designers, installers and users, European Plastics Pipes and Fittings Association (TEPPFA) initiated a research including interviews in four pilot countries: Poland, France, Germany and the UK. The first phase was concentrating on...

Author(s) : Suleyman Deveci, Nisha Preschilla, Birkan Eryigit

Pipes with inhomogeneous CB distribution showed 80% less elongation than pipes with homogenously distributed CB. Polymer domains with less or no CB (windows) showed delamination from the polymer matrix as the material elongated, finally leading to fracture much earlier than expected. In this study, we investigated the...

Author(s) : Suleyman Deveci, Birkan Eryigit, Senthil K. Kaliappan

The effect of eccentricity on the failure time of pipes under hydrostatic pressure test has a significant magnitude that it can easily mislead the evaluation of pipes according to requirement of ISO 4427-2. Therefore, authors propose a maximum relative eccentricity limit of 0.015, even lower, for pipes being tested...

Author(s) : Vivek Rohatg, Gregor Hiesgen, Mark J. Lamborn, Ashish M. Sukhadia, Douglas E. Simpson, David W. Borrego, Pamela L. Maeger

Maintaining dimensions within specifications is problematic for the extrusion of large diameter thick-wall polyethylene (PE) pipe (> 75 mm wall) due to sag caused by insufficient resin melt strength. However, sag can be controlled through careful resin selection and optimization of the pipe cooling process. This paper...

Author(s) : Amanda Hawkins, Jason Lawrence, Xiangli Meng

High Density Polyethylene pipes are used in various applications due to the material’s superior chemical resistance, pressure capability, and ductility. For the material to perform at the optimal design criteria, the connections and fabrications must be fused using repeatable procedures that specify proper fusion...

Author(s) : Christian Schalich

This paper introduces a new technology based on millimeter waves. It provides a noncontact, non-destructive, online measurement of inner and outer diameter, ovality, wall thicknesses, and sagging (sagging of the melt during solidification at a too high viscosity) of large plastic pipes during the extrusion...

Author(s) : C. B. Dandekar

Agriculture is the major occupation practiced in India, and irrigation is therefore a vital part of the entire water budget of the country. India possesses only 4% of the total world’s fresh water resource, of which, more than 80% is consumed solely in the Agriculture Sector (Dhawan, 2017). Canal based distribution...

Author(s) : Dominique GUEUGNAUT, Adil BOUJLAL, Aymeric LOPITAUX, Bertrand SEVRE

A special concept has been developed by GRTgaz Research and Innovation Center for Energy (RICE) for temperature mapping at the interface of an electrowelded assembly.The technical solution consists of a tubular piece in place of the real PE pipe, made of a non-weldable polymer with thermal parameters close to those of...

Author(s) : Bülent Kuzkaya

Spiral wound pipes are becoming more and more important in larger diameter HDPE pipe production technology. The spiral wound structured wall pipes with profiles are already well known and used for several low or non-pressure pipe applications. This paper shows that spiral wound pressure pipes can fulfill the...

Author(s) : R.J.M. Hermkens, H. Colmer, H.A. Ophoff

To investigate the suitability of PE pipes for the transport of hydrogen on a specific industrial site, three topics were investigated. These topics are: the chemical resistance of PE to hydrogen, the permeation rate of hydrogen through PE and the electrofusion of PE pipes exposed to hydrogen. It can be concluded that...

Author(s) : Pavel Hutar, Jan Poduska, Pavol Dlhy, Andreas Frank, Jaroslav Kucera, Jiri Sadilek, Gerald Pinter, Lubos Nahlik

This paper investigates possible use of recycled material as a part of a multilayer polyethylene pressure pipe system. Crack propagation in different configurations is simulated. Lifetimes of pipes containing recycled material are calculated. Results are compared with lifetimes of pipes made of virgin...

Author(s) : Jacob John, Andrew J. Ortquist, Mats Thunwall, Patrik A. Roseen

This study investigates production of crosslinked polyethylene (PEX) pipes using a resin obtained from a renewable resource via twin-screw extruder technology. PEX pipes were extruded using petroleum-based and renewable high-density polyethylene (HDPE) for comparison. Testing using relevant ASTM standards on the new...