Plastic Pipes Conference Association # 1995 Edinburgh
Brown
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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