Papers
Plastic Pipes Conference Association # 2018 Las-Vegas
Mario Messiha, Andreas Frank, Isabelle J. Berger, Jan Heimink, Hermann van Laak, Florian Arbeiter, Gerald Pinter
Since the last decade polyamide 12 (PA12) has been successfully introduced as material for SDR 11 gas piping systems up to 18 bar, representing itself as an attractive alternative to steel pipes for high-pressure applications. Practical experience has confirmed that beside the higher strength, PA12 pipe grades also show an excellent resistance against relevant pipe failure mechanisms such as slow crack growth (SCG) as well as any third-party attack or external surface damages. Within the current paper, four different PA12 materials with varying macromolecular structure were investigated. On the one hand, a major focus was put on the general applicability of the Cyclic Cracked Round Bar (CRB) Test as fracture mechanical test method. On the other hand, the influence of the molecular weight, expressed by the relative viscosity number VNrel, on the fracture mechanical failure behavior was examined. The results demonstrate that the Cyclic CRB Test is a suitable method to provoke real SCG, and that the viscosity number has a considerable influence on the SCG resistance of PA12.
Related papers
Author(s) : Ajay Taraiya, Peter Degenhart, Mark Boerakker
In PPXX, a technology was presented for the first time that could bi-axially orient polyolefin pipes. With this technology, it is possible to prepare pipes that have a performance far beyond the standard ones. One approach to achieving this performance is via a continuous in-line process. To optimize the in-line...
Author(s) : Kevin Copher, Patrick Vibien
High Density Polyethylene (HDPE) conduit is a durable product designed to protect cables for multiple generations buried underground or encased in concrete. Conduit is subject to coiling stresses, installation stresses and in-service stresses, such as those generated from installed curvature, soil loading, or rock...
Author(s) : Shawn R Coombs, PE
Pipelines through embankments should be designed to withstand extreme weather-related events and everyday stressors. As extreme weather-related events are on the rise because of climate change, it is important to ensure proper design, construction, and inspection practices are understood and executed. This paper...
Author(s) : James F. Mason, Akshay Ponda, Hermann van Laak, Tobias Bauer
The long-term strength of unplasticized polyamide 12 (PA-U12) has been characterized using standard methods for plastic pressure pipe during the qualification process for use in buried piping systems for natural gas delivery operating at low ambient temperatures, usually less than 20 to 30°C at pressures...
Author(s) : Dr. Michael Pluimer, Sara Stone
The Notched Constant Ligament Stress test (NCLS test, ASTM F2136)[1] is a test method that measures the slow crack growth in High Density Polyethylene. The NCLS test requires a notch on all test specimens to act as a stress concentration at that point so crack propagation can be easily predicted and studied. In...
Author(s) : Ernst van der Stok, Mirko Wenzel, Thomas Kratochvilla, Kurt Engelsing, Werner Weßing, Britta Gerets
It has not been possible to derive an accelerated procedure for the Point Load Test (PLT) as a pipe test before now. Further research and testing were therefore needed to establish appropriate requirements for standards including EN 1555-1 to rule out uncertainty in the market. The PLT is a central product test for...
Author(s) : Sunwoong Choi, Robert Stakenborghs , Pyeongan Lee, Byoungho Choi
This work developed a hydro-axial tension (HAT) test as a whole pipe axial tensile test and applied to evaluate the polyethylene (PE) pipe and fusion joints containing various flaws. HAT test was designed to utilize hydrostatic pressure to cause axial tension in pipes. The experimental and numerical analysis was...
Author(s) : Norbert Jansen
A practical requirement of temperature resistance of minimum 50 years at 70°C was established for the extra high voltage (EHV) corridor projects in Germany. Experts have debated what tests are best suited to prove the suitability of a pipe resin for cable protection pipes which may be installed hastily and under...
Author(s) : Aisha Khaleel, Suleyman Deveci, Sulistiyanto Nugroho, Fatima AlHameli
The use of polyethylene pipes in transportation networks of pressurized water and gas have shown superb performance over the history. High density, high-molecular-weight, and bi-modal polyethylene materials, known as PE80, PE100 and PE100RC, have successfully served the market for many years in standard applications....
Author(s) : Jessica Hinczica, Mario Messiha, Florian Arbeiter, Gerald Pinter
In Europe, only 1.8 million tons of recycled material is processed in new products within the building and construction sector [1]. Recyclates and blends of recyclates with virgin materials are already used for different products in the plastic pipe industry, such as cable trays, or storm water management...
Author(s) : Jiyong Park, JaeHyuck Han, YoungGu Kim, Eunjin Park
This study investigates the influence of various parameters on polymer design to determine the slow crack growth. HDPE(High Density Polyethylene) materials with different molecular weight distribution and comonomer content for PE100-RC pipe were investigated with cracked round bar test. The cracked round bar test...
Author(s) : Michael Pluimer, Christian Herrild, Patrick Vibien
With enhanced interest in a circular economy and the potential use of recycled HDPE within HDPE conduit, a research project was undertaken to investigate the necessary technical requirements when using recycled HDPE. High Density Polyethylene (HDPE) conduit is a durable product designed to protect cables...
Author(s) : Rafael A. García-Muñoz, Rafael Juan, Mónica de la Cruz, Beatriz Paredes, Carlos Domínguez
Plastics are widely used in various industries, resulting in the generation of significant amounts of plastic waste, which causes environmental and economic problems. Although mechanical recycling is the most commonly employed technology, the resulting recyclates often suffer from degradation and contamination. This...
Author(s) : Carine Lacroix, Philippe Louvel, Danielle Mark, Dominique Gueugnaut
A test program was carried out on two Polyamide resins, Polyamide 11 (PA11) and Polyamide 12 (PA12), both certified for gas networks. Polyamide’s advantage lies in its implementation, similar to that of polyethylene, and its properties allowing it to operate at up to 18 bar for gas, all other conditions being equal....
Author(s) : Shane Schuessler, Richard Coombs, Mohamed Hageb, Abdullah Saber, Grigorios Vigellis, Chandra Basavaraju
Bordered by Rwanda and the Democratic Republic of Congo sits Lake Kivu, an African Great Lake formed along the East African Rift. Lake Kivu is one of the world’s deepest freshwater lakes and contains enormous quantities of dissolved carbon dioxide and methane gas held at depths greater than 1100 feet (350 meters)....
Author(s) : Gerald Pinter, Lukas Travnicek, Johannes Wiener, Jan Poduska, Florian Arbeiter, Pavel Hutar
Crack initiation and subsequent crack growth are known to be the key factors which determine the final lifetime of a polymeric pipe. Subsequently, exact knowledge regarding the crack growth behavior is a key issue to guarantee safe operation. Furthermore, novel concepts are needed to satisfy increasing demands, for...
Author(s) : Carlos Domínguez, Predrag Micic, Rafael Juan, Nuria Robledo, Rafael A. García-Muñoz
Slow Crack Growth (SCG) resistance is the main property that must be controlled for assessing the long-term performance on polyethylene resins used for pipe application. The latest generation of bimodal and multimodal ethylene-α-olefin copolymers with exceptional balance of mechanical properties and processability...
Author(s) : Jay Parvez, Richard Nichols
All thermoplastic and thermoset pipes must consider the impacts of cyclic loading on overall performance. Since its first use, PVC pipes have been tested for its resilience to such loading. As testing evolved over time, the method to determine cyclic capacity for gasketed PVC pipes has improved. Previously, the...
Author(s) : Suleyman Deveci, Aisha Khaleel, Birkan Eryigit
Short and long term hydrostatic pressure resistance of plastic pipes are measured according to ISO 1167, by applying an internal pressure that is calculated for the target hoop stress considering outer diameter and wall thickness of the pipe samples. Due to the nature of the extrusion process, wall thickness...
Author(s) : Ali M Alghamdi, Recep Yaldiz, Faisal Almana, Yousof Ghazzawi, Abdul Rahim Arafath, Ratnesh Khandelwal, Azzedine Kioul, Turki Al-Shahrani, Salem Al-Anazi, Sarfraz Abbasi, Mohammed Aljasser, Parthipan B, Kavya A, Harm Caelers
Reinforced thermoplastic pipes (RTPs) are multilayer structured pipes reinforced with high-strength materials such as fibers (glass, aramid, or carbon fibers). RTPs are used to transport highly corrosive mediums at elevated pressures and temperatures. An example of that is the use of RTP in the Oil & Gas industry to...
Members of the Association
