Market Opportunities
Plastic Pipes Conference Association # 2004 Milan
Meijering, Wolters, Hermkens
One of the options for a low-pressure gas distribution system is the use of ductile PVC pipes and joints. The long-term performance of ductile PVC pipes has been reported in a number of previous studies. In this paper the long-term performance of the socket joints, in which elastomeric (NBR) sealing rings are used, is evaluated. The long-term quality of socket joints in ductile PVC pipeline systems has been determined by various tests on a number of excavated joints, which have been in operation for more than 20 years. Leak tightness determined according to the present specifications did fulfil all requirements. The quality of the rubberrings , established by e.g. tensile testing and hardness tests, was also still at the level of new rubberrings. The socket joints started only to leak at deflections of the pipes far exceeding the deflection levels met in field practice. The compression set of the excavated samples was also rather low and extrapolated to long times will not exceed a maximum required value of 70 % before 50 years. These results once again show that ductile PVC pipe systems for low-pressure gas distribution exhibit an excellent (long-term) performance.
Related papers
Author(s) : Sjoerd Jansma, René Hermkens
More than 20,000 km of rigid PVC (or PVC-U) pipes are currently in use for the distribution of natural gas in the Netherlands. In this decade, the majority of these pipes will reach their initially specified lifespan of 50 years. In the light of a possible replacement surge, it is increasingly important to identify...
Author(s) : R.J.M. Hermkens, H. Colmer, H.A. Ophoff
To investigate the suitability of PE pipes for the transport of hydrogen on a specific industrial site, three topics were investigated. These topics are: the chemical resistance of PE to hydrogen, the permeation rate of hydrogen through PE and the electrofusion of PE pipes exposed to hydrogen. It can be concluded that...
Author(s) : René Hermkens, Ernst van der Stok, Johannes de Bruin, Jeroen Weller
The replacement of fossil fuels like natural gas by sustainable gases such as biogas and hydrogen can mitigate global warming. There has been some debate about the impact of sustainable gases on the materials used in the gas grid. An extensive study of the behaviour of PE, PVC, POM and rubber materials was therefore...
Author(s) : J. Weller, R.J.M. Hermkens, E.J.W. van der Stok
To prevent an enormous surge in the replacement costs of the Dutch PVC gas distribution grid a so-called Exit Assessment programme was started in 2004. This programme determines the actual quality of old excavated PVC-U and PVC-Hi pipes using a tensile-impact test at temperatures varying from -25°C to +47,5°C, whereby...
Author(s) : MSc. J. Weller, R.J.M. Hermkens
More than 75,000 km of PVC pipes are currently in use for the distribution of natural gas in The Netherlands, which make up over 60% of the distribution grid. To gain insight in the factors that influence the quality of those pipes a so called Exit Assessment programme was started in 2004. Part of this programme...
Author(s) : Tiem Meijering, Jeannette Mulder, Günter Dreiling, Heinz Vogt
In this study, it has been demonstrated that a 100 years service-lifetime for non-pressure sewage pipes, solid wall pipes and structured-wall pipes of PE and PP, can be expected provided some basic conditions are met. It has been demonstrated that the resistance to thermo-oxidative degradation of the applied materials...
Author(s) : Emiel Drenth, Ton Bor, Roy Visser and Mannes Wolters
Various non-destructive methods, based on different physical principles, were investigated for their ability to differentiate between uPVC pipes having various levels of gelation. It was found that the micro-hardness method was not able to differentiate between uPVC samples of different levels of gelation. A possible...
Author(s) : Peter Postma & Hermkens René
The suitability of non destructive techniques for testing polyethylene pipe joints are investigated in a GERG (European Gas Research Group, www.gerg.eu) project. The results show that : • Both Ultrasonic and Microwave techniques have developed to a mature level. • For electrofusion joints good results are obtained...
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,...
Author(s) : Wolters, Wikkerink
The use of plastic pipeline materials in gas distribution systems is still increasing. Presently PE and high impact PVC are the dominating materials in gas distribution networks up to 4 bar. Most of these networks operate at these pressures, only a limited part of the network operates at higher pressures, up to 10 to...
Author(s) : Meijering
The possible effects of plastics pipes on drinking water quality are frequently in discussion and require the highest attention of our industry. On one hand, the European Commission (EC) is working already long time to set up a European Acceptance Scheme (EAS), so far without the desired speed. The Plastic Pipe...
Author(s) : Meijering
Teppfa and Plastics Europe initiated a comprehensive study to provide quantitative figures of the quality of sewers after long life service of up to 30 years. The overall aim and purpose of the project was to determine which sewer pipe materials better fulfil the requirements of sustainability in its broadest sense,...
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...
Author(s) : Nury, Meijering
After long time of preparation and co-normative research, the new European Acceptance Scheme for Drinking Water quality (EAS) is progressing now very strongly and will become in force as officially expected in 2006. So, besides the legally required CE marking showing the conformity to the Essential Requirements of the...
Author(s) : Meijering
In the Netherlands, a gas distribution system of Ductile PVC with elastomeric sealing ring joints and several special features is already operating to full satisfaction during more than 35 years. Today, Ductile PVC is the preferred material in this market. The total length of the gas distribution net is about 110.000...
Author(s) : Wikkerink, Wolters, van den Berg, Huppes
Environmental aspects tend to be increasingly important in designing gas distribution systems and in selecting gas distribution materials. Therefore the environmental aspects of various materials options for gas distribution networks were analyzed by means of a quantitative life cycle assessment. This paper describes...
Author(s) : Wolters
In the Netherlands, rigid PVC and impact-modified PVC pipes have been used in gas distribution systems for dozens of years. In general, these pipes have performed excellently. Some years ago, however. questions were raised about the resistance of these materials to certain gas constituents. An extensive research...
Author(s) : Horst, Weyn, Hermkens
For a long time the energy distribution companies in the Netherlands have expressed their need for ways of effectively assessing the quality of field-installed PE-pipe systems to prove integrity and reduce maintenance and repair costs. This becomes especially important with the increased use of these PE-systems for...
Author(s) : Scholten, Wolters
An investigation has been carried out into butt welding and electrofusion welding of PEX pipes, which had been crosslinked using the peroxide, silane and electron beam processes (PEXa, PEXb and PEXc respectively). A new hypothesis was set-up to explain the good weld quality of PEXa pipes electrowelded with regular...
Author(s) : Meijering
For reasons of environment and energy savings, the sales of High Efficiency Boilers have been stimulated in the last years. The low temperature flue gas emission which is characteristic for these boilers, leads to condensation of the flue gases in the chimney, attacking the masonry. The condensates contain aggressive...
Members of the Association
