P. F. Schoeffl, R.W. Lang
Papers # 2014 Chicago
To accommodate the recent industrial interests to utilize PE-HD pipes for oil field applications (e.g. injection water pipes, flow lines), this paper introduces a “fully integrated test concept” to allow a comprehensive pipe lifetime prediction under severe environmental conditions. Moreover, experimental set-ups and test procedures were designed and implemented to characterize material behavior under superimposed mechanical-environmental loading at the specimen level (5A and CRB) and at the component level (pipe testing) covering failure analysis in all three of the main failure regimes (Region I to Region III) [1-3] in order to allow for a 25 year lifetime prediction of PE pipes in oilfield service.
PE 100 and PEXc pipe materials were selected as model materials. Mechanical-environmental tests were conducted at two test temperatures (35 °C and 60 °C) in liquid hydrocarbons (LHC; 90/10 w-% i-octane/ toluene) and in deionized water as a reference environment. Pipe testing under liquid hydrocarbon pressurization (including results of 10 000 hours test duration) revealed a reduction in long-term hydrostatic strength (LTHS) by approx. 50 % compared to water pressurization. With respect to changes in slow crack growth (SCG) behavior, cyclic tests with cracked round bar specimen (CRB; conducted for more than 10 million failure cycles under full media immersion) revealed, that at low stress intensity factors (SIF) the LHC saturated samples indicate a superior SCG resistance compared to samples tested in water. Moreover, the observed failure mode of LHC saturated CRB specimens was designated as cyclic shear yielding, in contrary to CRB tests in water, where crack-tip crazing was observed as the dominant failure mechanism. To account for material aging and degradation, long-term exposure tests up to two years were conducted and subsequently the oxidation onset temperature (Tox) was determined and supplemented by size exclusion chromatography (SEC) results.
Related papers
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) : Drew Mueller, Peter Dyke
HDPE Pipe holds a dominant position in several markets in North America: natural gas distribution, oil patch, mining, landfill and geothermal. So why are polyethylene’s municipal water and wastewater market shares so much lower than these other industries? How has the polyethylene industry been successful in growing...
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) : Lei Wang, Guozhi Xu, Qiaoping Qiu, Weihua Lu, Yanwang Han
PP-R (random copolymerized polypropylene) has been widely used in hot and cold water systems. However, the standard PP-R pipes have the disadvantages of a large high-temperature thermal expansion coefficient, an insufficient notched impact strength, and a low temperature and pressure resistance. In this paper, a new...
Author(s) : Donald Swen, Leanne Pichay, Nicholas Vallin, Alice Wu, Jim Johnston
In the rural commune of Ait Bayoud, Morocco, two of the most remote villages in the area, Ilguiloda and Izgouaren, live with water scarcity. To meet their water needs, women and children walk several kilometers to the nearest spring each day, often multiple times a day. Consequently, children cannot attend school...
Author(s) : Ilija Radeljic, Ebbe Smith
HDPE pipe can be relatively easily scratched during the manipulation on the site, which is especially true for the marine pipelines. Installing the scratched marine pipe with the S bend method presents a risk and repair methods are usually performed. Currently, there is no standard defining the repair procedure, in...
Author(s) : Andreas Moerman, Flip van der Valk, Mirjam Blokker KWR, Tjakko Haaijer, Jan Vreeburg,
Drinking water companies with ageing networks are facing vast amounts of drinking water network reconstructions during the coming decades. This development coincides with the energy transition, which puts pressure on the available space underground. These external drivers give drinking water companies an opportunity...
Author(s) : Anja Armani, Helmut Zanzinger
PE-pipes are used in applications at temperatures higher than 40°C and long service lives like drainage pipes in landfill basal lining systems, drainage pipes in tunnels with high cover heights, geothermal applications, power plant technology, mining, underground cable protection pipes for power lines for...
Author(s) : Dominique GUEUGNAUT, Pascal AUSSANT, Romuald BOUAFFRE, Myriam BECHROURI
Concerns regarding the environment and sustainable development have revived interest in the reprocessing and re-use of polymer materials from manufactured objects that have reached the end of their operating life. Within this framework, formal professional agreements have been put in place at global level under the...
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) : James F. Mason, Akshay Ponda, Hermann van Laak, Buc Slay
The effects of liquid hydrocarbons on long term strength of pipe grade thermoplastic resins is an important consideration when designing pressure pipe for use in the oil and gas industry. There is an extensive body of work going back several decades descri bing these effects for pipe grade polyethylenes, and all...
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) : Gerald Pinter, Johannes Wiener, Florian Arbeiter, Abhishek Tiwari, Otmar Kolednik
For pipe applications, catastrophic failure due to crack growth has to be prevented by all means. Techniques to develop new and even tougher pipe materials are explored in this contribution. The aim is to create a multi-layer architecture, that exhibits high toughness as well as damage tolerance towards sharp notches....
Author(s) : Greg Scoby, PE
This paper will detail the steps taken during adoption of HDPE for potable water systems improvements including material justification, creation of related specifications, investigation of available piping components, qualification of contractors and the construction/inspection of related systems. The City of...
Author(s) : Christian Schalich
Plastic pipes for infrastructure and building applications are precisely specified with regards to wall thickness and diameter. Pipe manufacturers use different measuring methods in order to ensure the required dimensional accuracy and maintain a constant high quality. This paper introduces a measuring system based on...
Author(s) : Eng. Grigorios Vigellis, Eng. Mohamed Hageb
Continuous development and innovation in the production of plastic pipes made by high density polyethylene (HDPE) has enabled the industry to produce much larger diameter systems than ever believed possible. The enablers for production of such large plastic pipes are three main pillars: continuous innovation...
Author(s) : Jennifer Ravereau, Jose Teixeira Pinto, Malena Bernabeu, Jose Alacid, Jean-Philippe Le Goff, Frederic Mohier, Benjamin Rabaud
Drinking water network fittings such as valves are made of brass materials known to be robust over long periods. Due to the gradual inflation metallic raw material costs, composite plastic valves have grown in market share. Uncertainties remain, however, on their long-term reliability. The aim of this work is to...
Author(s) : Suleyman Deveci, Nisha Preschilla, Sulistiyanto Nugroho, Birkan Eryigit
Carbon black (CB) has been used as a perfect and the cheapest solution to prevent photo degradation of polyethylene against UV light exposure. The effect of carbon black on the mechanical properties of polyethylene pipes was studied extensively, but only on well dispersed and distributed carbon black...
Members of the Association
