Methods for Tightness Testing of Plastics Pressure Pipelines [PE]
# 1992 Eindhoven
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 predict the
increase of the tensile strain in the pipe wall
during the time of tightness testing solely based
upon the initially observed strain increase. This
is due to the fact taht the strain plotted in a
lin strain versus log time-diagram follows a rectilinear course and consequently does also the
water volume change in the pipeline.
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