Analytical Model of Stresses Caused by Over-Belling PVC Pipe

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) : Markus Gall, Reinhold W. Lang, Joerg Fischer, Ansgar Niehoff, Steven Schmidt

Despite recent efforts in promoting the utilization of recycled polymeric materials for more diverse and more advanced applications, there are still significant knowledge gaps with regards to the applicability of certain recyclate types for specific “re-use” purposes. When it comes to pipe applications, for instance,...

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) : Richard St-Aubin, Dr. Thomas O’Rourke, Dr. Brad Wham, Blake Berger

Molecularly oriented polyvinyl chloride (PVC-O) pipe has been found to withstand large ground deformation during seismic events without damage. The properties of PVC-O pipe that support this performance have been investigated in a multi-year testing program undertaken at the Geotechnical Lifelines Large Scale Testing...

Author(s) : Andreas Frank, Isabelle J. Berger, Mario Messiha, Carl-Gustaf Ek, Norbert Schuler, Jens-Martin Storheil, Erwin Mayrbäurl, Steve Heeley, Frank Krause, Lodewijk Niemöller, Philippe Gabriëls, Yogesh S. Deshmukh, Florian Arbeiter, Thomas Koch, Gerald Pinter

In order to improve the circular economy of polymers in terms of sustainability and reduced carbon footprint, the increased use of recyclates has become a topic of major importance. Due to their long design lifetimes, pipe applications represent an excellent opportunity to create added value to non-virgin polymers. In...

Author(s) : Lonnie Corley, Dane Chang, Harvey Svetlik, Matt Brandes, Thomas Musto, Frank Schaaf, David Fink

This paper presents a brief overview of a challenging project at the Callaway Nuclear Power Plant where HDPE was utilized to replace degraded steel buried piping in a Safety Related water system. Callaway was the first Nuclear Power plant to obtain NRC approval and successfully place the HDPE piping system into...

Author(s) : Francis Reny Costa, Anh Tuan Tran, Jeroen Oderkerk, Thomas Hjertberg, Christophe Salles, Ulf W. Gedde, Benjamin Rabaud, Flavia Zraick

The premature failure of polyethylene pipes in contact with high chlorine and chlorine dioxide, used as residual disinfectants in drinking water distribution, remains an area of concern for water companies particularly in regions where temperatures are regularly or seasonally high. Multiple factors can amplify the...

Author(s) : Steven Folkman, Ron Bishop

There are guidelines in AWWA standards for de-rating a PVC pipe’s pressure class if the operating temperature exceeds 23°C. These de-rating factors are appropriate for a system operated at a constant elevated temperature. In the warm desert climates in the USA it is common for the water mains to exceed room...

Author(s) : Steven Folkman, Ron Bishop

One of conditions design engineers face is selecting an appropriate pipe wall thickness (or DR) that will accommodate both maximum operating pressure and repeated surge pressure events. Methods for assessing the number of cycles to failure is quite well developed for PVC pipe. Fracture mechanics approaches can be very...

Author(s) : Thomas C. Pedersen, Robert R. Kwapisz

This paper presents rheological data on simple rigid PVC compositions lubricated paraffin wax, calcium stearate, and oxidized polyethylene wax. These three materials comprise the most widely used lubricant system for rigid PVC in North America. The influence of certain paraffin wax characteristics will be discussed....

Author(s) : Stefan Kremling, Thomas Hochrein, Peter Heidemeyer

In plastics industry, the use of terahertz technology opens up opportunities for novel non-destructive and contactless testing applications. For example, the thickness of individual layers of a foamed multilayered plastic pipe can be monitored contactless and continuously during the extrusion process. Furthermore,...

Author(s) : Michael Pluimer, Rick Thomas

A new test method was developed to evaluate the stress crack resistance of HDPE materials containing recycled content. The method involves testing un-notched specimens in an elevated temperature bath under a specified stress. The new test method was published in March of 2016 as ASTM F3181, Standard Test Method for...

Author(s) : Reinhold W. Lang, Patrick R. Bradler, Joerg Fischer, Dominik Poehlmann, Steven Schmidt, Ansgar Niehoff

In the present paper, a highly effective test and characterization concept for polymer recyclate materials is proposed and validated. Based on the proposed methods, a study was carried out to investigate the potential of in-plant and post-use PE recyclates from various applications to be utilized in PE recyclate...

Author(s) : Tomas Helenius, Karin Jacobson, Thomas Blomfeldt

Polyethylene is the leading material for new installation of drinking water pipes in Sweden. The material is recognized by the market as a flexible, light weight and an inexpensive solution. The material is ideal for water piping, however the lifetime is only guaranteed for 50 years. This is a problematic limitation...

Author(s) : Steven Horwatt, Randall Duderstadt, Douglas Keller, Sameer Mehta

The development of an antioxidant package for potential use in chlorine resistance of polyethylene pipe is a timeintensive exercise. Previous studies have shown that simple bench top experiments in the solution phase, coupled with LC-MS as a rapid tool for evaluating the analysis of antioxidant reaction products after...

Author(s) : Bill R. Vanhoose, Jarrett A. Nelson, Christa K. McNish, Richard W. Thomas

The Stepped Isothermal Method (SIM) is a form of Time-Temperature Superpositioning (TTS) that involves measuring the creep rate of a sample while it is subjected to a series of isothermal temperature steps. The accelerated temperature results can then be shifted back to room temperature to produce a master-curve....

Author(s) : Steven Folkman

Several analytical studies have estimated that PVC pipe can have a useful life of over 100 years. The earliest widespread use of PVC pipes was in Germany in the late 1930’s. These early pipes lacked proper extrusion technology. Extrusion technology was greatly developed during the 1950’s and 1960’s. Use of PVC pipe in...

Author(s) : Andreas Frank, Anita Redhead, Thomas Kratochvilla, Heinz Dragaun, Gerald Pinter

Key words : Polyethylene, pipe, test method, lifetime, slow crack growth For a qualitative characterization of the slow crack growth resistance of polyethylene pipe grades several test methods are available. Especially for modern pipe grades these test methods exceed practical time frames and new acceleration methods...

Author(s) : Francis R. Costa, Christophe Salles, Anh Tuan Tran, Jeroen Oderkerk and Thomas Hjertberg

Over the years polyethylene has gained preference as the material of choice for water distribution pipes due to its long successful track record offering comparatively lower frequency of leakage, corrosion resistance, flexibility, light weight, easy installation, etc. However, in recent years, there have been growing...