This specification covers a high temperature, compression set and fluid resistant fluorocarbon (FKM) elastomer in the form, of O-rings, compression seals, O-ring cord, and molded-in-place gaskets for aeronautical and aerospace applications. These products have been used in contact with air and a wide variety of fuels, lubricants, specific hydraulic fluids, and a variety of gas turbine engine lubricants, including higher thermo-oxidative stability (HTS) lubricants, including those conforming to MIL-PRF-23699 Class HTS, MIL-PRF-7808 Grade 4 and AS5780 Class HPC, however usage is not limited to such applications. This material type has a typical service temperature range of -40 to +400 °F (-40 to +204 °C). These products are not suitable for use in phosphate ester based hydraulic fluids. Each application should be considered individually.
AMS-R-83485 is being superseded by two specifications: AMS7287 replaces AMS-R-83485 (Type I parts) for compression seals and an AMS3000-series specification will replace AMS-R-83485 (Type II parts) for moulded shapes. A new part standard has been produced (AS83485) that will supersede AMS-R-83485/1, although the M83485-XXX numbering system will be retained. The technical requirements of AMS-R-83485 have been maintained in this document, with the addition of a long-term compression set requirement, replacement of STD / SPC class gas turbine lubricants with AMS3085 (i.e. BP Reference Oil 300, representative of HTS class gas turbine lubricants), and the addition of a glass transition (Tg) value/requirement.