Tu Xiang-qun, Wang Chao, Cheng Zhong-lin, Dong Bo-bo
Papers # 2016 Berlin
This paper is to verify the impact of different contents of nucleating agent and annealing processes on the content of β-crystal. By using four-parameter equation of PP-RCT with requirements in different application conditions, different temperature coefficients and Miner's rules the design stress of PP-RCT materials under different applications and the calculation process of test pressure of the PP-RCT pipes have been deduced, which can facilitate the better understanding and learning of relevant standards for plastic piping engineers. Moreover, it provides reference for the research and development of plastic pipe materials and quality control method.
As the third generation of polypropylene material, random copolymer polypropylene (PP-R), with good mechanical properties, non-toxic, good heat resistance and long-term creep resistance etc., has been widely used as the hot & cold water pipe system in construction buildings. However, when the installation is taken under at low ambient temperature, the brittle fracture could happen. In order to increase the low temperature impact resistance and heat resistance of PP-R pipes, the improvement of crystal structure of PP-R pipe by adding the nucleating agents has been proposed by many researches. The PP-R with modified crystalline structure is called PP-RCT. It is found from the longterm hydrostatic pressure test curve of PP-RCT, obtained by material modification, no knee point is observed before 8760h at any temperature, including 110 ℃, which indicates there is no brittle failure.
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) : Chris Ampfer, Gene Palermo, Ernest & Oren Lever
This paper looks at the origin of the 10% allowable scratch depth rule for polyethylene (PE) pressure pipe developed in 1971 and research that has been performed over the years since its inception to determine the validity of this rule. The 10% rule has been used by natural gas pipeline operators since the 1970’s to...
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) : Joe Babcanec, P.E., Dan Currence, P.E.
The newly released Drainage Handbook provides complete guidance on corrugated polyolefin pipe. Perhaps the biggest contribution this new handbook makes to the advancement of both HDPE and PP corrugated plastic pipe is the design procedure presented. The design procedure reflects the industry’s recommended practice for...
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) : Sjoerd Jansma, René Hermkens
More than 20,000 km of rigid PVC (or PVC-U) pipes are currently in use for the distribution of natural gas in the Netherlands. In this decade, the majority of these pipes will reach their initially specified lifespan of 50 years. In the light of a possible replacement surge, it is increasingly important to identify...
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) : 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) : 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) : White G. Jee, Wes Long, Marcello Russo
In 2018, the North American HDPE pressure pipe market experienced unprecedented demand and growth especially in the region of the Permian basin in west Texas. 1 As aninnovative means of increasing HDPE pipe supply in this region, the first modular mobile extrusion plant was moved to Pecos, TX. Using custom designed...
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) : Dustin Langston
The design and installation of polyethylene systems can be complex, specifically due to the many applications and environmental conditions that surround those systems. Online design tools have been developed to address this complexity and the various factors that must be considered. These online tools used widely in...
Author(s) : Steve Sandstrum, Chris Ziu
The market for high performance polypropylene (PP) piping systems in North America continues to evolve. Generally, PP piping systems have performed exceptionally well in a variety of challenging HVAC, industrial and plumbing applications. As a result, the engineering community in North America is embracing higher...
Author(s) : Ulrich Schulte, Dr. -Ing. Joachim Hessel
In order to protect the Austrian lakes effectively against the discharge of effluent, a 13 km long pressure pipeline made of high density polyethylene was laid on the bottom of Lake Ossiach back in 1971. The DN355 to DN200 pipes were produced from a first generation HDPE-compound. The classification would have been...
Author(s) : Guido Quesada
An important breakthrough for belled PVC pipe was made around 2006, when the first versions an integral joint restraint were released, after about two years in development. This type of restraint comprises a casing, usually made of metal such as ductile iron or stainless steel, a rubber seal, and a “C” grip ring,...
Author(s) : Alireza Sahaf Amin, Dr. Gholamreza Pircheraghi
PE-Xa pipes used in the hot water supply are required for high mechanical strength and high creep resistance at high temperature. Because of the higher cross-link degree of PE-Xa pipes as compared with other crosslinked pipes methods , these pipes which are made by peroxide crosslinking have better performance in the...
Members of the Association
