Slow crack growth resistance of non-virgin polymers

Author(s) : A. Marangoni

The quality of infrastructures is a key driver for maximizing the performance of the utilities networks and minimizing the environmental impacts associated with their operation. The water and sewer pipes are key network elements to guarantee a satisfactory service to the citizens. Their end-of-life management is an...

Author(s) : A. Taraiya, P. Degenhart, M. Soliman, M. Boerakker, R. Handstanger, R. Kleppinger

Since the introduction of polyolefins for pressure pipes, continuous improvements have been made to meet ever-higher demands on their performance and to expand their application window beyond their original scope, mostly based on new resin formulations. Today, we also continue to push the limit to provide better...

Author(s) : Derek Muckle

A technical program has been undertaken to provide evidence on the suitability of polyethylene pipe and fitting systems for the distribution of hydrogen fuel gas. The underlying principle has been to evaluate material in the form of a pipe and to consider the performance of the pipe and of the welded jointing systems...

Author(s) : Paul J. Freudenthaler, Joerg Fischer, Mathias Eder, Reinhold W. Lang

For controlled water disinfection, typically chlorine is used and preliminary studies demonstrate its aging and crack growth acceleration effects on polyolefin pipe materials [1, 2]. Although the use of recycled plastics is not prohibited in some ISO standards for polyolefin piping systems [3–5], only small amounts...

Author(s) : Shuhei Nishida, Shintaro Iwasaki, Hidefumi Yamanaka, Takahiro Kasatani

Polyethylene pipelines have been used for natural gas service applications for over 40 years in Japan. It is thought that they will continue to be used widely for many years. Therefore, it is important to confirm the conditions of the existing pipelines being used for the long term. In this study, polyethylene pipes...

Author(s) : Ernst van der Stok

For PE 100-RC, two tests are still under development for pipes: the point load test (PLT) and the accelerated notch pipe test (aNPT). The PLT was developed by a project group consisting of manufacturers and end users. The PLT determines the resistance to point loads as they can occur in practice. An earlier study...

Author(s) : S. Nestelberger, J. Cheng

The Point Load Test (PLT) [‎ 1, ‎ 2] was designed to simulate the SCG (slow crack growth) failure initiated by a rock pressing into the exterior wall of a polymer pipe. Today’s PE materials sustain long PLT testing times, due to its high SCG resistance design. Consequently, an accelerated “PLT+” with the support of...

Author(s) : Amster Howard

Flowable fill is used for many applications, but mainly for pipe trench embedment and backfill. There are three ways that using flowable fill can be kind to the environment. Because flowable fill is self-leveling and has a strength greater than the native soil, the trench cross section can be minimized. This means...

Author(s) : Mario Messiha, Britta Gerets, Jan Heimink, Andreas Frank, Florian Arbeiter, Gerald Pinter

A majority of field failure of viscoelastic plastic pipes can be attributed to slow crack growth (SCG) and has become crucial in terms of characterization of newly developed materials – particularly, if they are designed for pressurized pipe applications. In this study, investigations in terms of SCG resistances...

Author(s) : M. Eckes & Dr. B. Baudrit, Dr. M. Troughton & D. Wylie, H. van Laak & J. Fritz

Unplasticized polyamide 12 (PA-U12) is increasingly being used in pipe applications, especially in the gas sector. However, the material behavior in the usual quality tests for pipe welds has not yet been thoroughly investigated. For this reason, two research institutes, worked in cooperation with a manufacturer of...

Author(s) : Thomas R. Kratochvilla, Patrick Grünbeck, Christoph Bruckner, Raimund Eremiasch, Harald Wilhelm, Mario Vukelja

In the last decades pipe dimensions of extruded PE pipes have reached new orders of size. Today, PE pipes with outer diameters of up to DN/OD 3500 mm are produced and used for pressure pipe applications like seawater intake/discharge, outfall, sewage and industrial process piping systems. To test the long-term...

Author(s) : Lukas Travnicek, Pavel Hutar, Jan Poduska, Andreas Frank, Florian Arbeiter, Jaroslav Kucera, Jiri Sadilek, Gerald Pinter, Lubos Nahlik

The application of recycled material in pressure piping systems has been considered lately – it was suggested, that the recycled polyethylene could be used as a part of a multilayer pipe together with virgin material. This type of pressure pipes is not availableon the market yet, so their properties can be only...

Author(s) : Ludo Debever, Peter Sejersen

The European Plastics Strategy is a priority for the European Union. Recycling more post- consumer plastics (PCRs) is paramount. That is why the Circular Plastics Alliance has been established. The alliance gathers public and private stakeholders in the plastics value chains to promote voluntary actions and...

Author(s) : Justin Brandt, Mike Griffin, Tony Cuvo

As plastic pipe gains share in new markets and applications, additional joining methods add further value, enabling continued growth for plastic pipes. To date, definitions of a “fit-for-purpose” mechanical joint for High Density Polyethylene (HDPE) pressure piping systems can vary significantly. As such, mechanical...

Author(s) : Dr Ruediger Liske, Dr Tobias Eltze, Dr Tania Weyland, Marie-Laure Bertet

The migration of NIAS (Non-Intentionally Added Substances) into potable water is a recurring topic for the distribution of cold and warm drinking water and related materialsindustry. These substances are chemical compounds that are present in drinking water contact materials but have not been added during the...

Author(s) : Mark Boerakker, Rudy Deblieck, a Harm Caelers, Arno Wilbers, Tine Boonen a DSM, Britta Gerets, Mirko Wenzel

Components made of plastic are facing ever-increasing demands with respect to their production, use and durability. This also holds for gas and drinking water pressure pipes made of high-density polyethylene (PE-HD), where service lifetimes of up to 50 years and in some cases even 100 years are required. One of the...

Author(s) : Andreas Frank, Mario Messiha, Günter Dreiling, Norbert Schuler, Jens-Martin Storheil, Erwin Mayrbäurl, Stuart Ramella, Frank Krause, Rudi Berning, Philippe Gabriëls, Alpay Aydemir, Thomas Koch, Florian Arbeiter, Gerald Pinter

The Cyclic Cracked Round Bar (CRB) Test has been applied to study the slow crack growth (SCG) resistance of virgin, recycled, and reprocessed PVC-U. This fracture mechanical test allows a quick ranking of the SCG resistance of PVC-U. A clear correlation between the K-value and the SCG resistance has been elaborated....

Author(s) : Andrew J. White, Paul Dietz

FP-Pigments is a global manufacturer of a unique series of titanium dioxide pigment products and have been supplying the coatings, plastics, paper and inks markets for over 10 years, helping our customers reduce their raw material costs while maintaining product quality and performance. We have plants in both...

Author(s) : E. Boccaleri, L. Palin, G. Rombolà, M. Milanesio

In the last decades, research on nanostructured materials as additives for plastics involved several polymeric matrices, but only limited studies and publications involve PVC. In this work, the context of rigid application of PVC (U-PVC) for pipes application was targeted, in order to test and evaluate the structural...

Author(s) : Sjoerd Jansma, Peter Cloos, Ernst van der Stok

This paper describes two different test methods used to determine the permeation rate of hydrogen through a reinforced thermoplastic pipe (RTP) system with a HDPE liner pipe and a gas-tight layer at a pressure of 42 bar(g) hydrogen and ambient temperature. One method involThe results of the aforementioned tests...