Plastic Pipes Conference Association # 2006 Washington DC
Hojer, Janson, Oderkerk, Venator
For nearly three decades two technology processes have been available for production of PEX piping by moisture induced silane crosslinking (PEX-b). The first technology, the Sioplas™ process, was invented and patented by Dow Corning. This process requires extruding pipe from a reactive compound composed of silane groups which have been grafted onto polyethylene (PE) polymer chains by the addition of organic peroxide in an offline compounding process. The second technology, the Monosil™ process, was developed by Maillefer as a one-step-process where all of the components of PE base resin, additives, peroxide and silane are grafted in a specialized compounding extruder which also extrudes the pipe in-line. This paper describes a new innovative technology process that offers the PEX pipe industry a third choice in materials for producing PEX-b piping. The Vinyl Silane Copolymer or Visico™ process, invented and patented by Borealis AS, copolymerizes the silane directly into the PE polymer chain during the polymerization process. This ensures an excellent homogeneous distribution of the reactive silane sites and avoids the heavy use of organic peroxides needed by the other PEX-b technologies to graft the silane component. The resulting product offers greater process stability and higher purity for superior taste & odor performance in PEX piping. All of these technologies require post treating the pipe with steam or hot water to induce the crosslinking reaction and produce PEX-b pipe although the new Borealis Ambicat™ catalyst system for MDPE PEX-b radiant heating pipe enables crosslinking to take place during pipe storage at ambient temperatures by absorbing moisture from the surrounding air in the warehouse or yard.
Related papers
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) : 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...
Author(s) : Lars Selling and Ingrid Andersson, Christophe Salles and Lars Höjer
Kungsors Plast AB, in co-operation with Borealis, has pioneered the underground plastic piping for petrol filling stations with the first polyethylene piping used by Shell Sweden in 1981. The retail sector with petrol filling stations has used PE-based underground piping since the early 1980s. With increased...
Author(s) : Bassewitz, Janson, Liebel
From Jan 6th 2001 until March 31st 2005 a research project, funded by the German Ministry for Economy and Research had been carried out in order to investigate technical details not yet researched. The results of the project have shown that polymer flexible pipes for district heating are fit for purpose. The research...
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) : Janson, Bergstroem, Baeckman, Blomster
When performing strength quality control of PE pressure pipes made of new grades it is important to take the creep vs. time into consideration and not only the common stress vs. time behaviour. Thus, it is just the relation between linear strain and logarithmic time, which will within a reasonable testing time help...
Author(s) : Janson
Sustainable Development’ is a concept which is often used today, particularly when discussing necessary efforts for preventing persistent environmental problems. It came up as a result of the findings already by the Rome Club et al in the early 70s’, implying that the natural resources of the earth are limited and in...
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...
Author(s) : Janson
At the International Conference on Plastics Pipes W in Bath 1988, a paper was presented by the Author called : "Physical ageing of buried PVC sewer pipes as affecting their long-term behaviour". The tests performed on constantly deflected pipes referred to at that time had been running for approximately one year....
Author(s) : Janson
New research and development particularly concerning the long-term strain of modern PE resins have created a basis for a simple and adequate method for tightness testing of plastics pressure pipelines. Thus, it is shown that for plastics pipes subjected to constant internal hydraulic pressure, it is quite possible to...
Author(s) : Janson
The investigation has indicated that deflected uPVC pipes are subjected to a physical aging process, which gives rise to a lower rate of decrease in the E-modulus than has previously been assumed. Based upon these findings the long term ring stiffness of PVC sewer pipes is determined. Concerning the bending strength...
Author(s) : Janson, Molin
In the Nordic countries common research work concerning buried sewer plastics pipes has been followed by an independent evaluation group led by the authors. This group was founded in 1968 by the Nordic plastic industries in order to create a forum for independent evaluation of all the various research programmes so...