2018 Las-Vegas : Design of large diameter buried pipes
Author(s) : Anders Andtbacka, Frans Alferink, Peter Sejersen
The behavior of buried plastic pipes is already well described in standards and technical specifications and as well as proven in real life conditions. Plastics pipes in diameters up to around 400 mm are already in use for more than 60 years and pipes with larger diameters for more than 20 years now. All with good...
2016 Berlin : Determining the residual quality of PE pipes using the strain hardening test
Author(s) : Ernst van der Stok, Frans Scholten
Samples machined directly from pipe show that orientation has a large influence on the strain hardening modulus. No effects arising as a result of residual stresses were found. Samples machined in the axial direction from a hydrostatic pressurised pipe showed no effect as a result of this mechanical degradation. For...
2016 Berlin : Predicting the lifetime of PE50 gas pipes under point loading
Author(s) : Frans Scholten, Ernst van der Stok
The residual quality of first generation PE50 gas pipes, installed in Netherland between 1961 and 1979, is still remarkably good. The only premature failures of a few PE50 pipes were exclusively caused by point loads. When under point loading, they started failing in practice after 8 to 26 years, in a brittle manner....
2016 Berlin : Residual quality of excavated UPVC gas and water distribution pipelines
Author(s) : Frans Scholten, Ernst van der Stok, Britta Gerets, Mirko Wenzel, Mike Boege
The current condition of 35-50 years old uPVC main (110 mm) and service (32 mm) pipes for gas and water distribution was assessed. From 27 excavation sites in total about 400 segments of 1.2 meters length each were tested using many techniques. The K-value (average molecular weight) of the PVC, the degree of gelation...
2016 Berlin : The experience with the use of UPVC pipes in various buried applications
Author(s) : Frans Alferink
PVC pipes for buried applications for water, sewer and gas, has developed an excellent track record. PVC is very inert, has a high resistance against permeation of soil contaminations and gas components and meanwhile has a long proven lifetime. Next to that, the lifecycle costs of buried PVC pipe systems are amongst...
2014 Chicago : Designing Against Rapid Crack Propagation in PVC Water Pipes
Author(s) : Frans Scholten, Ernst van der Stok, Jan Breen
Very occasionally PVC-U water pipes suddenly fail due to a long brittle crack with a length of many meters which propagates with the speed of sound along the pipe and causes extensive water loss. This phenomenon has been recognized as Rapid Crack Propagation (RCP). The conditions under which RCP can occur are an...
2014 Chicago : PVC-O: Expanding in Technology and Application
Author(s) : André Nijland, Frans Alferink
PVC-U is used around the globe for potable water supply and sewer applications. This is due to its strength and stiffness as well as to its excellent flow properties. PVC-U shows an excellent performance in protecting the potable water quality. And it is registered that failure rates of PVCU pipelines are very low....
2014 Chicago : Two Complementary Tests to Determine the Quality of PE 100RC
Author(s) : Ernst van der Stok, Frans Scholten
The Strain Hardening (SH) test and the Point Load Test (PLT) are two complementary tests designed to determine the quality of PE 100-RC. The SH test is a resin test, whereas the PLT is a pipe test. The SH test is a tensile test performed at 80 °C. Extensive research on the SH test has been conducted and published in...
2010 Vancouver : Pa pipes for 16 bars gas pipelines
Author(s) : Frans Scholten and Mannes Wolters
PA11, PA12 and plasticized PA6.12 pipes are interesting candidates for gas transport and
distribution pipelines at 16 bars pressure, which is beyond the maximum pressure for
PE100 pipeline systems (10 bars). However, PA pipelines are not meant as an alternative
to PE pipelines, but to steel pipelines. Therefore,...
2006 Washington DC : Buried Plastics Chambers - Performance
Author(s) : Alferink
Plastics pipes products are more and more appreciated in sewer schemes throughout the world.
The advantages of thermoplastics, like the good resistance against sewer environments and the
possibility to built complete tight systems are many times the drivers to use thermoplastic pipes
and chambers. Plastics chambers...
2004 Milan : Combined Loading of Buried Thermoplastics Pressure Pipes
Author(s) : Janson, Alferink, Wolters
This paper presents the results of work that was performed at the request of TEPPFA , The
European Plastics Pipes and Fittings Association, on the issue of “Combined loading”
(external and internal loading) of buried thermoplastics pressure pipes.
The work is of great importance for users and designers of...
2001 Munich : Performance of Buried Plastics Manholes
Author(s) : Alferink
When starting with the application of buried thermoplastics pipes in the fifties, Wavin started
to gain a lot of experimental experience with these pipes, which later formed a solid base
for the correct application of thermoplastics pipes. In analogy, a lot of experimental
experience is gained now with buried manholes...
1998 Gothenburg : Design of Thermoplastics Pipes
Author(s) : Alferink, Janson, Olliff
Extensive field trials are being performed in a project sponsored by TEPPFA and APME,to
obtain well documented information about the behaviour of buried thermoplastics pipes. as
outlined in the paper by Alferink, Bjorklund and Kallioinen (Ref 1). This information is of
vital importance to obtain a workable design...
1998 Gothenburg : The Design of Thermoplastics Pipes
Author(s) : Alferink, Bjoerklund, Kallioinen
Over the last 15 years several attempts have been undertaken to establish a design method for
plastics pipes (IS0 TC138 WG13) and over the last ten years to establish an unified design
method for all buried pipes (CEN TC1641165 JWGI). Several national methods are available
and it is shown over the last ten years that...
1995 Edinburgh : Old PVC gravity sewer pipes Long Term Performance
Author(s) : Alferink, Guldback, Grootook
Wavin gained a lot of experience with operational PVC sewer pipes by monitoring installations and measuring pipe deflections over a period of about 35 years, as reflected in the database "PiPer". Some of the oldest pipes have been measured and dug up now to study the durability of these pipes. Furthermore the results...
1992 Eindhoven : Effect of Installation Conditions on Buried Plastics Pipes
Author(s) : Alferink, Wolters
Results of deformation measurements carried out
on buried plastics pipes installed at six
different tests sites are discussed in this
paper. The results show that the deflection of
buried pipes is usually rather small and the
time dependence is limited to a few years after
installation. Traffic loading does not result...