Typically, with medium pressure seals, high friction and hollow wear occur due to pressure deformation at the elastomeric flex section of the seal—resulting in an enlarged contact band width.
 Freudenberg Sealing Technologies’ medium- and high-pressure Simmerring® shaft seals are designed to prevent this deformation via a combination of a shorter flex section, flex section support features, reinforced metal cases, defined lip geometries, and proprietary wear-resistant materials.
The Freudenberg Sealing Technologies’ Premium Pressure Seal (PPS) features a patented lip design which keeps the lip profile stable up to twice the level of pressure loading of conventional designs. The PPS seal works like a standard Simmerring shaft seal, with a spring-loaded lip that applies a radial load on the shaft in order to perform the sealing function. The dust lip provides superior protection from dirt ingress and other contamination in order to prevent deterioration of the oil lip. This design is particuarly effective under conditions of pressure cycling (pressure spike).
 
Please send us to email if you want to know more technical details: may@meiouseal.com