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b.safe TECHNISCCAHLEININFOFORRMMATAITOIONNEN
b.safe Elastomers
Their main characteristic is their elasticity: Elastomers can easily be stretched and bent and return to their original shape and size after being released. These synthetic materials are most commonly used for o-rings, flat gaskets or resilient elements.
NBR – Acrylonitrile-Butadiene-Caoutchouc
NBR is an elastomer on the base of acrylonitrite-butadiene-caoutchouc which is used as budget-priced sealing material (e. g. O-rings for stopcocks). This material has a good resistance in mineral oils and fats and is also resistant to HFA, HFB and HFC-hydraulic fluids. It has a very good elasticity. PERBUNAN® (trade name of company BAYER AG) is not resistant to brake fluids on the base of glycol, HFD liquids, aromatic compounds (e. g. benzole), ester, ketone and amines as well as in concentrated acids and caustic solutions. That is why it is not the ideal material for the chemistry.
FKM – Fluorocaoutchouc
Elastomer on the base of fluorocaoutchouc, more familiar as VITON®(DuPont). Many O-rings, lip seals and sleeves are made of FPM. It has a very good resistance to heat, chemicals, weather and ozone. Furthermore, it is resistant to sulphurated mineral oils and fats and to hardly inflamma- ble HFD liquids (basis phosphor ester or chlorinated hydrocarbon). It is not resistant to anhydrous ammonia, caustic soda, potassium, ketones, ether, dioxane, as well as some amines and organic acids. For b.safe products, FPM is mainly used as sealing material, mostly protected from the medium by a PTFE sealing lip.
EPDM
FHFFFF
... C F
C X
H F
C C Y C C F F F
F
C Z ... F
EPDM 3 is an elastomer on the base of ethylene-propylene-diene-caoutchouc
which is mostly used for gaskets and O-rings. The main applications are in ... CH2 CH2 X CH2 CH Y CH CH Z ... the area of hot water, steam and suds. It is not resistant to hydraulic fluids CH3 CH2 onthebaseofmineraloilbutitisweather-proof,non-ageingandresistant CH CH3 n to ozone. At BOHLENDER, EPDM O-rings are mainly used for applications
where VITON® O-rings are not sufficient.