Plastic Pipes Conference Association # 2021 Amsterdam
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 the actual material quality of these pipes.
To gain an insight into the remaining quality of the PVC-U pipes in the Dutch gas distribution grid, an Exit Assessment program was initiated in 2004. This program determines the quality of existing PVC-U material by measuring the brittle-to-ductile transition temperature of the excavated pipes with the tensile impact test [1,2]. The ultimate goal for Dutch Distribution System Operators (DSOs) is to assess the remaining quality in the field using non-destructive techniques, without the need to remove pipe segments.
This paper provides an insight into the correlation between spectrophotometric measurements and hardness measurements of the ductility of PVC pipes, revealing the usefulness of these non-destructive techniques for determining the quality of PVC pipes.
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