Re: Hydraulic Floor Jack
Keep in mind there are Buna rubber o-rings suitable for water based products. And Viton o-rings are for use in chemical/petrol applications.
Buna o-rings will work for a while in petrol applications, but they will eventually get to soft and fail.
Not exactly true.
Acrylonitrile-Butadiene (NBR)
Nitrile rubber (NBR) is the general term for acrylonitrile butadiene
copolymer. The acrylonitrile content of nitrile sealing
compounds varies considerably (18% to 50%) and influences
the physical properties of the fi nished material.
The higher the acrylonitrile content, the better the resistance
to oil and fuel. At the same time, elasticity and resistance to
compression set is adversely affected. In view of these opposing
realities, a compromise is often drawn, and a medium
acrylonitrile content selected. NBR has good mechanical
properties when compared with other elastomers and high
wear resistance. NBR is not resistant to weathering and
ozone. See Figure 2-2.
Heat resistance
? Up to 100?C (212?F) with shorter life @ 121?C (250?F).
Cold flexibility
? Depending on individual compound, between -34?C
and -57?C (-30?F and -70?F).
Chemical resistance
? Aliphatic hydrocarbons (propane, butane, petroleum
oil, mineral oil and grease, diesel fuel, fuel oils) vegetable
and mineral oils and greases.
? HFA, HFB and HFC hydraulic fl uids.
? Dilute acids, alkali and salt solutions at low temperatures.
? Water (special compounds up to 100?C) (212?F).
Not compatible with:
? Fuels of high aromatic content (for fl ex fuels a special
compound must be used).
? Aromatic hydrocarbons (benzene).
? Chlorinated hydrocarbons (trichloroethylene).
? Polar solvents (ketone, acetone, acetic acid,
ethylene-ester).
? Strong acids.
? Brake fl uid with glycol base.
? Ozone, weather and atmospheric aging.
Fluorocarbon (FKM)(aka Viton DuPonts trade name) has excellent resistance to high temperatures,
ozone, oxygen, mineral oil, synthetic hydraulic fl uids,
fuels, aromatics and many organic solvents and chemicals.
Low temperature resistance is normally not favorable and
for static applications is limited to approximately -26?C
(-15?F) although certain compounds are suitable down to
-46?C (-50?F). Under dynamic conditions, the lowest service
temperature is between -15?C and -18?C (5?F and 0?F).
Gas permeability is very low and similar to that of butyl rubber.
Special FKM compounds exhibit an improved resistance
to acids and fuels.
Heat resistance
? Up to 204?C (400?F) and higher temperatures with
shorter life expectancy.
Cold fl exibility
? Down to -26?C (-15?F) (some to -46?C) (-50?F).
Chemical resistance
? Mineral oil and grease, ASTM oil No. 1, and IRM 902
and IRM 903 oils.
? Non-fl ammable hydraulic fl uids (HFD).
? Silicone oil and grease.
? Mineral and vegetable oil and grease.
? Aliphatic hydrocarbons (butane, propane, natural gas).
? Aromatic hydrocarbons (benzene, toluene).
? Chlorinated hydrocarbons (trichloroethylene and
carbon tetrachloride).
? Gasoline (including high alcohol content).
? High vacuum.
? Very good ozone, weather and aging resistance.
Not compatible with:
? Glycol based brake fl uids.
? Ammonia gas, amines, alkalis.
? Superheated steam.
? Low molecular weight organic acids (formic and
acetic acids).
