Influence of Additives in Synthetic Oils on Radial Lip Seals

This project has been initiated in order to get a general basic understanding about the influence of additives onto elastomeric lip seal systems. It is necessary to determine the behavior with single additive base oil compounds. Two different synthetic base oils, Polyglycol (PG) and Polyalphaolefin (PAO), are used. Thus 19 different single additive base oil compounds have been reviewed. Two different elastomeric materials NBR and FPM have been taken for all the tests. In several dynamic tests the influences on the sealing systems have been investigated. These included tests for 24 hours to measure the friction torque and tests for 10 hours to measure the pumping rate. Furthermore, the operating conditions during 96 hours functional tests have been determined. A concluding view onto the compatibility, respectively the incompatibility, of the additives in these different points of view will be given.