Metallized Carbon Corporation has introduced mechanical seal primary rings for sealing refrigerants and other low viscosity liquids.

Designing mechanical seals for sealing refrigerants and other low viscosity liquids has been a difficult problem for seal manufacturers for many years.  It has now been established that mechanical seals with antimony impregnated, carbon-graphite primary rings and solid silicon carbide counter face rings can solve this problem.  Low viscosity liquids such as Freon refrigerants, liquid oxygen, liquid carbon dioxide, propane, ethylene and acetone are being successfully sealed using mechanical seals with Metcar Grade M-444, antimony impregnated, carbon-graphite primary seal rings.