New discoveries in stabilizing drinking water pipes in contact with chlorine dioxide

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) : Nolene Byrne, Rasike De Silva, Keith Lenghaus, Tim Hilditch

Plastic pipes have been utilized in the Australian gas distribution network since the early 1970s. The most common plastic type found in Australia is polyethylene (PE), although nylon is extensively used in New South Wales. Early installation of PE pipe was completed using the first generation high density type PE50...

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) : M. Boerakker, S. van Mierloo, D. v. Beek, R. Schipper, P. Voets, M. Soliman, K. Jacobson, D. Lukes, B. Rabaud, F. Zraick

HDPE pipes are used for standard pressurized water pipes, offering an excellent solution for safe transport of (drinking) water. The HDPE pipe market is growing globally. Especially in countries that suffer from water scarcity, surface water and water from rivers have to be used for drinking water supply. To guarantee...

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) : Joerg Fischer, Paul J. Freudenthaler, Patrick R. Bradler, Reinhold W. Lang, Susan C. Mantell

This research addresses the effect of nucleation on the global aging behavior and the fatigue crack growth (FCG) resistance of commercial alpha- and beta-nucleated polypropylene random copolymer pipe grades (PP-R) when exposed to chlorinated water (5 mg/l free chlorine) at an elevated temperature of 60°C. Comparing...

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) : Joerg Fischer, Patrick R. Bradler, Reinhold W. Lang

In the present paper, a novel test system for conducting fatigue crack growth (FCG) experiments under superimposed mechanical-environmental conditions is presented. FCG experiments were performed on a polypropylene (PP) grade and a short-glass fiber reinforced polyamide 66 (PA-GF) grade as model materials. The...

Author(s) : Ilari Aho, Volker Meyer, Peter Sejersen

The lack of a cross-border acceptance of the approval of the hygienic requirements for plastic pipes systems is inefficient and expensive for the industry. The costs for testing of a pipe system range from a few thousand Euro to more than €30k /reference 3, 4/. The European Plastic Pipe and Fitting Association...

Author(s) : Sarah Eisenstat, Peter Dyke

Many cities in the US are operating their water utility on a “manage to fail” basis, meaning they are replacing >100-year-old pipes at a cycle time of over 150 years. At this rate, most of the pipes will have failed before they can be replaced. Ft. Wayne, IN made the realization that PE pipe is the solution due to its...

Author(s) : Marc van Loo (Dr.), Constant Van Aerschot, KumHoong Lou

In many parts of rural developing Asia and even some parts of Africa, sewerage from households is often discharged directly to the surrounding. This unfortunate fact means that many waterborne diseases such as cholera, dysentery and typhoid continue to afflict these communities. Numerous efforts from governments,...

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...