Correlation of oxidative induction time with thermal and radiation aging of EPR and XLPE cable insulation

摘要

The objective of the project described is to determine the extent to which radiation and thermal aging of cable can be assessed by the measurement of oxidative induction time (OIT). Since OIT can be obtained from very small samples of insulation, OIT measurement can be considered as a nondestructive testing method. Ethylene-propylene rubber (EPR) and cross-linked polyethylene (XLPE) cable insulation materials frequently used in nuclear power plants were used in the tests. The OIT is shown to decrease at a faster rate with aging than elongation to rupture. Early results of this investigation indicate that OIT is an effective method for measuring aging.