Efficient method for characterizing the service lifetime of rubber seals

Seal applications require rubber compounds capable to endure numerous cycles of deformation without crack initiation. A lab testing equipment named Intrinsic Strength Analyzer (ISA (TM)) has been used to investigate the crack initiation energy of different rubber compounds typically used for seal applications. Four compounds were investigated. The compounds were based on two different types of ethylene-propylenediene-monomer (EPDM), varied quantity of carbon black (CB) and varied types and quantities of curing agents. On hand of the compounds analyzed could be shown first of all, the intrinsic strength is an indicator for service lifetime of seals. Secondly, the predominant effect of varied rubber type on the crack initiation energy compared to the lower influence of other chemicals used has been observed.Ministry of Education, Youth and Sports of the Czech Republic DKRVO [RP/CPS/2020/004, IGA/CPS/2020/007