NBR: the practical general-purpose choice
NBR, or nitrile rubber, offers strong resistance to petroleum oils, hydraulic fluids, greases and fuels. It is widely available, mechanically durable and cost-effective for pumps, compressors, hydraulic systems and general machinery.
FKM: performance for demanding conditions
FKM, commonly known by the Viton trade name, provides stronger resistance to high temperatures, aggressive chemicals, fuels, ozone and weathering. It typically costs more but can deliver longer service in harsh environments.
NBRTypical range: −40°C to +120°CExcellent oil resistanceModerate chemical resistanceLower cost
FKMTypical range: −20°C to +200°CExcellent oil resistanceExcellent chemical resistanceHigher cost
What to confirm before ordering
- Fluid or chemical compatibility
- Minimum and maximum operating temperature
- Pressure and movement
- Environmental exposure
- Required service life and maintenance interval
When the specification is uncertain, send FLR the dimensions, operating fluid, temperature and equipment application for review.