Know the different characteristics of the seals used in our products: Viton, EPDM, FPM, NBR, etc.
Reminder: The correct compatibility of valve seals with the product contained in an IBC is the responsibility of the product packer.
FPM SEALS (OR FKM OR VITON OR FLUORINATED RUBBER)
Obtained by polymerising vinylidene fluoride (VF) and optionally using varying amounts of hexafluoropropylenes (HFP), tetrafluoroethylenes (TFE), hydropentafluoropropylenes (HFPE) and perfluor (methyl vinyl ether) (FMVE). Tetrapolymers with a fluorine content of 65-71% can be produced. The particular importance of FKM-based materials lies in their high temperature resistance and chemical stability. The gas impermeability is excellent. Resistance to ozone, weathering and sunlight cracking is good, as is flammability. Animals can have a destructive effect on the material.
Good resistance to swelling in:
Oils and greases (and most additives), fuels and aliphatic as well as aromatic hydrocarbons, some difficult-to-flame hydraulic fluids and synthetic aircraft engine oils.
Strong swelling in:
Polar solvents and ketones, hardly flammable hydraulic fluids of the skydrol type, brake fluids, for example ATE.
Thermal use range:
Approximately -20°C to +200°C (with peaks at +230°C).
EPDM SEALS (OR FLUORINATED ETHYLENE PROPYLENE RUBBER)
Polymer of ethylene, propylene, with a small amount of Diene. Ethylene Propylene Rubber (EPM) is a polymer of Ethylene and Propylene. Moulded parts and sealing elements made of EPDM are preferably used in washing machines, dishwashers and sanitary fittings. Seals made of this material are also used in hydraulic systems with low-flammability hydraulic fluids of the HFC and HFD groups and in hydraulic brake systems. EPDM elastomers show very good resistance to ozone, ageing and weather conditions. EPDM elastomers have very good resistance to ozone, ageing and weathering and are therefore suitable for the manufacture of profile strips and sealing strips that are subject to weather conditions.
Good resistance to swelling in:
Hot water, steam, lye, oxidising media, acids, bases, polar organic media, ketones, hardly flammable hydraulic fluids from the HFC group and some types from the HFD group, brake fluids, e.g. ATE-SL.
Strong swelling in:
Aliphatic, aromatic and chlorinated hydrocarbons.
Thermal use range:
Approximately -50°C to +150°C.
NBR SEALS (OR VITON OR BUTADIENE ACRYLONITRILE OR NITRILE)
Polymeric compound of butadiene and nitrile-acrylic. The nitrile-acrylic portion can be between 18 and 50% of the formulation. Good resistance to swelling in :
Aliphatic hydrocarbons, e.g. propane, butane, petrol, mineral oils (lubricating oils, hydraulic oils of groups H, H-L and H-LP) and in mineral oil-based greases, flame-retardant hydraulic fluids of groups HFA, HFB and HFC, vegetable and animal oils and fats, light fuel oils, diesel oil.
Good resistance to swelling in:
Fuels with high aromatic content (Superfuel).
Strong swelling in:
Aromatic hydrocarbons, e.g. Benzol, chlorinated hydrocarbons, e.g. Trichloroethylene, hardly flammable hydraulic fluids of the HFD group, esters, polar solvents, as well as glycol-based brake fluids, e.g. ATE and pentosin.
Thermal use range:
Between -30°C and +100°C. At high temperatures the material hardens.