抄録
Chlorine water test was carried out on the existing EPDM gasket and improved EPDM gasket of Grooved Coupling and degradation of the gaskets and physical behavior of their rubber under the influence of chlorine water was estimated. The improved EPDM gasket was estimated to degrade in approximately 114 years. The existing EPDM gasket was estimated to degrade in 11 to 16 years, but the degradation is not likely to affect its cutoff performance since physical behavior of its rubber did not change even after the degradation.
