ASTM D2837 and ISO/TR 9080 for
validating PE resins were analyzed. It
was found that the difference between
11.3 yr. and 50 yr. as specified in D2837
and ISO/TR 9080, respectively, has very
little effect on the determination of the
Long Time Hydrostatic Strength (LTHS)
at the service temperature, but this
difference has a significant effect on the
required resistance to slow crack growth
(RSCG). It is proposed that the PENT
Test (ASTM F1473) can be substituted for
the hydrostatic pressure test for
determining RSCG while maintaining
the same standard for validating the
resin. The PENT test is better because it
is faster, more prease, and takes fewer
tests to achieve the same validation
requirement for RSCG that is now
contained in the current specifications.
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As part of the Polytec Systems European-funded project, electrofusion (EF) joints in
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The Water Distribution Technical Centre
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The test, called PENT, consists in measuring the resistance to
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constant load in air. The specimen geometry is designed and
conditions are chosen so that failure is by slow crack growth as
occurs under service in the field. The test conditions for
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