Tribologically advantageous materials Gas-tight construction for low-molecular-weight gases piston rings seal the gas in the compression chamber of reciprocating compressors. They are customized, in terms of design and material, to the respective application conditions in refineries, the natural gas industry, as well as the petrochemical and chemical industries. The precisely manufactured rings also allow reliable operation with a long service life in industrial air production and many areas of process engineering. Piston rings, rider rings and bands are manufactured in various designs: One-piece or segmental straight Angle cut Step cut Twin Ring™ Double Twin Ring™ Two Segment Pressure balanced designs rings and has developed specific combinations for particularly problematic and demanding applications. This has also included numerous successful conversions from lubricated to non-lubricated operation.Pressure balanced rings are available, when deemed appropriate for high pressure applications and piston/rider ring combinations are also available for more specific applications. Large diameter piston rings up to 47” (1200mm) are custom manufactured for special requirements. A range of metallic piston and rider rings are also manufactured, using selected grades of bronze or cast iron, where operational requirements dictate.