Papers
Plastic Pipes Conference Association # 2016 Berlin
Vivek Rohatgi, Pamela L. Maeger, Ashish M. Sukhadia
This study is related to two common approaches used for pipe fabrication, viz. in-line compounding and extrusion of a pre-compound. Pipes were extruded using both approaches and properties were evaluated per the relevant ASTM and ISO standards for water and gas pressure pipe applications to compare the performance of extruded pipes. The results show that when high quality pipes are produced, the performance of pipes made via either in-line compounding or a pre-compound, is equivalent.
For pressure piping applications, the ASTM standard allows the use of in-line compounding wherein the natural resin pellets are physically mixed with the color masterbatch pellets just prior to pipe extrusion. The ISO standard, however, requires the use of a pre-compound, wherein the same two components are melt blended prior to pipe extrusion. Both these approaches are being used successfully for commercial pipe production globally. However, questions still arise as to how these two methods compare, in addition to ongoing questions about the implications of the carbon black particle size and screw design in influencing the overall processability (throughput) and quality of the extruded pipes. These factors were investigated in this study in which pipes were extruded on a 45 mm pipe extrusion line with 36 L/D grooved feed screw design using 1) in-line compounding of a bimodal high density polyethylene PE4710/PE100 resin and a commercial carbon black masterbatch, and 2) a precompound of the same two components. For blends prepared using in-line compounding, color masterbatches based on N550 (~ 42 nm) and P type (~25 nm) carbon blacks were used. For the pre-compounded resin, the N550 type carbon black based masterbatch was the same as for in-line compounding. Extruded pipes were evaluated for processability, carbon black content and dispersion, oxidation induction time (OIT) and thermal stability temperature, numerous physical properties common to pressure piping grades, quality of fusion joints, slow crack growth (SCG) via PENT, notched pipe test via ISO 13479 test method, rapid crack propagation (RCP) performance using the S4 test, and short term hydrostatic pressure testing via the 3- point ISO 1167 method and ASTM F714 standard. Results of the study are discussed in detail relating to both pipe processing and property performance and conclusions provided.
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) : Olivera Bilic, Vivek Rohatgi, Brody Peterson, David Hukill
Demand for conduit pipe is expected to surge globally due to rapid industrialization and urbanization in residential and commercial sectors. Just in the U.S., according to Market Research analysis, expected growth of the plastic conduit pipe market is at a CAGR of more than 5% over the next ten years. In response to...
Author(s) : Joe Babcanec, P.E., Issam Khoury, Ph.D, P.E., Shad Sargand,
The use of corrugated HDPE and PP pipe for gravity flow storm sewers is a growing trend throughout the United States. Many of these drainage pipes are buried in shallow cover conditions under roads with heavy traffic. It is well established that thermoplastic pipe installations under shallow cover respond differently...
Author(s) : Dolores Herran
MOLECOR continuing with its line of leading water infrastructure sector with its technological products, has recently developed a software that can be used through a mobile application or web browser with which users can digitalize and geolocate the different pieces that form a water infrastructure network. This is a...
Author(s) : Yi Zhong, Qianshi Ma, Haihua Yu
BSTRACT The residential district adopts central heating for low temperature radiators system. Due to the disrepair of the secondary heating pipe network that pipe from heat exchange station to user entrance, the running, leaking, dripping and leakage are serious, and the accidents occur frequently. The heat...
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) : Amster Howard
This paper explores the use of a composite soil stiffness as a valuable design tool to consider when a pipeline traverses through poor soil conditions. Thermoplastic pipe are flexible pipe and require good soil support at the sides of the pipe to minimize deflection. However, sometimes the trench walls are weak soils...
Author(s) : Michael O’Rourke
The required wall thickness for a fully fused HDPE water main subject to an earthquake induced lateral spread is addressed in this paper. The water main is assumed to be buried via cut and cover (i.e., open cut with typical burial depths in the 2 to 15 feet range) procedures and any laterals have small diameters. For...
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) : 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) : Jacob John, Suresh Shenoy, Patrik Roseen
Cross-linked polyethylene (PEX) pipes continue to gain popularity in plumbing and indoor climate applications around the globe. This study focuses on increasing the sustainability of PEX pipes by utilizing recycled PEX and production waste streams into PEX production. Different methods available for recycling and the...
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) : 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) : Jie Wu, Yushan Hu, Todd Hogan
Recycling of plastic materials is key to demonstrating that these high value materials are much more than a waste stream and a key component of a sustainable future. The plastic pipe market effectively utilizes in-plant recycle systems where standards and codes allow processors to recapture the value of these...
Author(s) : Mitsuaki TOKIYOSHI, Yutaka SAWADA, Yasuhiko OTSUKI, Kensei INOUE, Takashi KURIYAMA, Toshinori KAWABATA
Polyethylene reinforced with short glass fibres (PE-sGF) pipe, manufactured by combining short fiber glass (sGF) with PE100 as a reinforcing material, has a higher pipe rigidity in the pipe circumferential direction than that of PE100 because of the reinforcing effect of the reinforcing material and a performance...
Author(s) : Kevin White, Shad Sargand
The current standard of practice for the installation of agricultural mains is in accordance with ASTM F449, Standard Practice for Subsurface Installation of Corrugated Polyethylene Pipe for Agricultural Drainage or Water Table Control. ASTM F449 has several limitations. Currently, the allowable maximum height of...
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) : 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) : Yanlei Hu, Jin Sun
Slow crack growth is the main reason for brittle failure of polyethylene pipes. At present, the traditional slow crack growth test generally has many problems, such as too long test time, using chemical reagents that pollute the environment, poor reproducibility, etc., which limit the accurate evaluation of the slow...
Members of the Association
