O-Rings

NBR, aka Acrylonitrile-Butadiene or Nitrile Rubber has good mechanical properties and wear resistance compared with other elastomers.

Chemical resistance: aliphatic hydrocarbons (propane, butane, petroleum oil, mineral oil and grease, diesel fuel, fuel oils), vegetable mineral oils and greases.

Not compatible with: fuels containing high aromatic content, aromatic hydrocarbons (benzene), chlorinated hydrocarbons (trichloroethylene), polar solvents (ketone, acetone, acetic acid, ethylene-ester), strong acids, brake fluid with glycol base, ozone, weathering and atmospheric ageing.

Viton® is the Trademark for the chemical Fluorocarbon, or FKM. Viton® has excellent resistance to high temperatures, ozone, oxygen, mineral oil, synthetic hydraulic fluids, fuels, aromatics, and many organic solvents and chemicals. Viton® is not favourable for low temperatures.

Chemical resistance: Mineral oil and grease, non-flammable hydraulic fuels in the HFD group, silicone oil and grease, mineral vegetable oil and grease, aliphatic hydrocarbons (butane, propane, natural gas), aromatic hydrocarbons (benzene, toluene), chlorinated hydrocarbons (trichloroethylene and carbon tetrachloride), fuels with methanol content, high vacuum and good ozone, weather and ageing resistance.

Not compatible with: glycol based brake fluids, ammonia gas, amines, alkalis, superheated steam, low molecular organic acids (formic and acetic acids)

EPDM is a copolymer of ethylene and propylene, and has a chemical name of Ethylene Propylene Rubber. EPDM is particularly useful for phosphate ester hydraulic fluids and glycol-based fluids in brake systems.

Compatible with: hot water and steam (to 149°C) glycol based brake fluids, many organic and inorganic acids, cleaning agents such as sodium and potassium alkalis, phosphate ester based hydraulic fluids, silicone oil and grease, many polar solvents such as alcohols, ketones and esters, and is ozone, ageing and weather resistant.

Not compatible with: mineral oil products (oils, greases and fuels).

Silicone Rubber has a relatively low tensile strength, and poor tear and wear resistance. However, silicones have good cold flexibility down to -59°C, and heat resistance to 232°C. Silicones haves good ozone and weather resistance, as well as good insulating and physically neutral properties.

Chemical resistance: engine and transmission oil, animal and vegetable oil and grease, non petroleum-based brake fluids, fire resistant hydraulic fluids (HFD-R, HFD-S), hi molecular weight chlorinated aromatic hydrocarbons, moderate water resistance, and diluted salt solutions.

Not compatible with: superheated water steam (over 121°C), acids and alkalis, low molecular weight chlorinated hydrocarbons (trichloroethylene), aromatic mineral oil, hydrocarbon based fuels, aromatic hydrocarbons (benzene, toluene).

Polyurethane, or PU, have excellent wear resistance, high tensile strength and high elasticity compared to other elastomers.

Chemical resistance: pure aliphatic hydrocarbons (propane, butane), mineral oil and grease, silicone oil and grease, water up to 50°C, ozone and ageing resistant.

Not compatible with: ketones, esters, ethers, alcohols, glycols, hot water, steam, alkalis, amines, acids.

HNBR, or Hydrogenated Nitrile, is a synthetic polymer resulting from the hydrogenation of nitrile (NBR) rubber. HNBR compounds exhibit superior mechanical properties, particularly high strength.

Chemical resistance: aliphatic hydrocarbons, vegetable and animal fats and oils, HFA, HFB, HFC fluids, dilute acids, bases and salt solutions at moderate temperatures, water and steam up to 149°C, good ozone, ageing and weathering resistance.

Not compatible with: chlorinated hydrocarbons, polar solvents (ketones and esters), strong acids.

PTFE, is trademarked as Teflon®. PTFE is virtually impervious to all fluids and gases. PTFE orings are generally not subject to spiral failure. PTFE orings have, however, low sealing force due to their rigidity, no effective memory and high compression set.

Chemical resistance: chemically inert, solvent resistant.

Not compatible with: molten alkaline metals, flourine, some halogenated compounds at high temperatures.

AFLAS® is the Tradename for Tetrafluoroethylene-Propylene. AFLAS® has excellent chemical resistance across a wide range of aggressive media.

Compatible with: bases, phosphate esters, amines, engine oils, steam, pulp and paper liquors.

Not compatible with: aromatic fuels, ketones, carbon tetrachloride

Fluorosilicone, or FVMQ, has similar properties to Silicone (VMQ) and offers improved fuel and mineral oil resistance, but decreased performance with hot air resistance compared to silicone.

Chemical resistance: aromatic mineral oils (IRM 903 oil), fuels, low molecular weight aromatic hydrocarbons (benzene, toluene).

PTFE (Teflon) encapsulated Viton (FKM) orings consist of a core of Viton, with a relatively thin encapsulation of Teflon. Such orings are virtually a universal seal for hostile environments, combining the benefits of Teflon (chemical resistance, low permeability to gases and low coefficient of friction) with the elastomeric benefits of Viton (resilience and sealing force).

Chemical resistance: chemically inert, solvent resistant.

Not compatible with: molten alkaline metals, flourine, some halogenated compounds at high temperatures.

PTFE (Teflon) encapsulated Silicone (VMQ) orings consist of a core of Silicone, with a relatively thin encapsulation of Teflon. Such orings are virtually a universal seal for hostile environments, combining the benefits of Teflon (chemical resistance, low permeability to gases and low coefficient of friction) with the elastomeric benefits of Silicone (resilience and sealing force).

Chemical resistance: chemically inert, solvent resistant.

Not compatible with: molten alkaline metals, flourine, some halogenated compounds at high temperatures.

Neoprene, has good mechanical properties and wear resistance compared with other elastomers.

Chemical resistance: aliphatic hydrocarbons (propane, butane, petroleum oil, mineral oil and grease, diesel fuel, fuel oils), vegetable mineral oils and greases.

Not compatible with: fuels containing high aromatic content, aromatic hydrocarbons (benzene), chlorinated hydrocarbons (trichloroethylene), polar solvents (ketone, acetone, acetic acid, ethylene-ester), strong acids, brake fluid with glycol base, weathering and atmospheric ageing.