Lifetime Assessment of Polyethylene Pipes in Oil and Gas Infrastructure

Author(s) : Yilaing He, Tianjun Zhang

A new electrofusion PE belt is developed by reinforcing it with various layers of steel mesh. It’s of sandwich structure, consisting of steel mesh reinforcement, heating wire and polyethylene. One or more layers of steel mesh is encapsulated in the middle, and heating wire is embedded onto “inner side” of the belt....

Author(s) : Steven Folkman

A recent survey again confirms that PVC pipe has the lowest break rate when compared with break rates of ductile and cast iron, asbestos cement, steel, and concrete pipe. Other results of interest to water utilities and engineers are discussed. During 2017, Utah State University conducted a survey of utilities across...

Author(s) : Thomas R. Kratochvilla, Raimund Eremiasch, Christoph Bruckner

In the last years effort has been made to develop and standardise new accelerated test methods to evaluate PE 100-RC materials in short times in form of test bars. The two most important developments, the cracked round bar test (CRB test) and the strain hardening test (SH test) were published as final ISO standards in...

Author(s) : Gerald Pinter, Florian Arbeiter, Johannes Wiener, Andreas Frank, Otmar Kolednik

In order to further increase the fracture toughness of pipes, biomimetic layer design of the pipe wall can be used. Therein, soft polymer interlayers can act as crack-arresters in a matrix of stiffer and inherently more brittle polymers. The effectiveness of the crack arresting role of soft interlayers in a...

Author(s) : Ignacio Muñoz

During the last years PVC-O has become a popular product in pipe business due to the huge improvements of mechanical properties of PVC after orientation. At the same time, CPVC has become an important choice for hot water conduits in in-house applications. Molecor has started a research program to evaluate the...

Author(s) : Wang Zhanjie

As the largest production country, with numerous applications, China’s plastic pipe industry is developing steadily to meet the demand and needs. This paper analyzes the current situation and barriers, and proposes the breakthroughs to achieve a sustainable, stable and healthy development of China’s plastic pipe...

Author(s) : Jiang Tongjun, Fu Zhimin, Yang Yuanjin

This paper introduces the application of CPVC pipe in fire sprinkler systems in China. The advantages and differences of CPVC pipe versus to galvanized steel pipes, the improvement of related laws and regulations and the market outlook are discussed. The overall result is a change in the upstream and downstream...

Author(s) : Liang Yu, Akshay Ponda, Dane Chang

Following the development of US shale oil and gas production since 2007, the demand for thermoplastic pipes with better corrosion resistance, and lower installation and operation cost than carbon steel pipe, has been growing significantly. Nylon 12 has been qualified for hydrocarbon transportation in offshore flexible...

Author(s) : HU Fa, LI Yue, GAO Yuanjie, ZHE Dongmei, WEI Ruoqi

This paper expounds the development status of composite insulating pipe in the heating and chemical fields from the aspects of materials, structure and application. Combined with the relevant standards and technical requirements, the performance advantages and the key evaluation methods such as axial shear strength,...

Author(s) : Davidovski Zoran

To get a deeper insight in why plastic pipes systems in some cases are deselected by designers, installers and users, European Plastics Pipes and Fittings Association (TEPPFA) initiated a research including interviews in four pilot countries: Poland, France, Germany and the UK. The first phase was concentrating on...

Author(s) : Joerg Fischer, Paul J. Freudenthaler, Patrick R. Bradler, Reinhold W. Lang, Susan C. Mantell

This research addresses the effect of nucleation on the global aging behavior and the fatigue crack growth (FCG) resistance of commercial alpha- and beta-nucleated polypropylene random copolymer pipe grades (PP-R) when exposed to chlorinated water (5 mg/l free chlorine) at an elevated temperature of 60°C. Comparing...

Author(s) : Suleyman Deveci, Nisha Preschilla, Birkan Eryigit

Pipes with inhomogeneous CB distribution showed 80% less elongation than pipes with homogenously distributed CB. Polymer domains with less or no CB (windows) showed delamination from the polymer matrix as the material elongated, finally leading to fracture much earlier than expected. In this study, we investigated the...

Author(s) : Suleyman Deveci, Birkan Eryigit, Senthil K. Kaliappan

The effect of eccentricity on the failure time of pipes under hydrostatic pressure test has a significant magnitude that it can easily mislead the evaluation of pipes according to requirement of ISO 4427-2. Therefore, authors propose a maximum relative eccentricity limit of 0.015, even lower, for pipes being tested...

Author(s) : John Kurdziel, Michael Pluimer

Corrugated HDPE pipes have been successfully used for decades for sewers, culverts and land drainage applications and are advantageous due to their durability and service life in a variety of installation conditions. Pipes used for highway and storm sewer applications typically require stricter material standards than...

Author(s) : Vivek Rohatg, Gregor Hiesgen, Mark J. Lamborn, Ashish M. Sukhadia, Douglas E. Simpson, David W. Borrego, Pamela L. Maeger

Maintaining dimensions within specifications is problematic for the extrusion of large diameter thick-wall polyethylene (PE) pipe (> 75 mm wall) due to sag caused by insufficient resin melt strength. However, sag can be controlled through careful resin selection and optimization of the pipe cooling process. This paper...

Author(s) : Joerg Fischer, Patrick R. Bradler, Reinhold W. Lang

In the present paper, a novel test system for conducting fatigue crack growth (FCG) experiments under superimposed mechanical-environmental conditions is presented. FCG experiments were performed on a polypropylene (PP) grade and a short-glass fiber reinforced polyamide 66 (PA-GF) grade as model materials. The...

Author(s) : Mitsuaki TOKIYOSHI, Gentaro TAKAHARA, Joji HINOBAYASHI, Toshinori KAWABATA, Takashi KURIYAMA

Glass fiber reinforced polyethylene pipes and fittings are controlled for bending characteristics (Strength and stiffness) for vertical and axial directions of pipe by spiral cross winding method. Generally, to use this method, it takes much stronger for vertical strength than axials cause of extruded direction,...

Author(s) : Michael Pluimer, Richard Thomas

Over the past decade, there have been several key research projects to evaluate the performance of corrugated HDPE pipes manufactured with post-consumer and postindustrial recycled materials for highway and railroad drainage applications. Three of these projects were recently completed and published (NCHRP Project...

Author(s) : Ilari Aho, Volker Meyer, Peter Sejersen

The lack of a cross-border acceptance of the approval of the hygienic requirements for plastic pipes systems is inefficient and expensive for the industry. The costs for testing of a pipe system range from a few thousand Euro to more than €30k /reference 3, 4/. The European Plastic Pipe and Fitting Association...

Author(s) : Sarah Eisenstat, Peter Dyke

Many cities in the US are operating their water utility on a “manage to fail” basis, meaning they are replacing >100-year-old pipes at a cycle time of over 150 years. At this rate, most of the pipes will have failed before they can be replaced. Ft. Wayne, IN made the realization that PE pipe is the solution due to its...