... weak corrosive medium. Combination of materials Seal face: Graphite, Silicon carbide, Tungsten carbide ,Aluminum oxide Secondary sealing: Acrylonitrile rubber ... mechanical seals (John Crane, Burgmann, ROTEN)- OEM dry gas seal mechanical seals (Gundfos, APV, FRISTAM, Alfa-Laval, SIHI, ... seals based on drawings or samples provided by customers- Seal Rings in different materials (SSiC, RBSiC, TC, Ceramic, ...