Common rubber sealing materials include nitrile rubber (NBR), fluororubber (FKM/Viton), silicone rubber (VMQ), ethylene propylene diene monomer (EPDM), neoprene rubber (CR), polyurethane rubber (PU), and natural rubber (NR), etc. Different materials are suitable for different working conditions and media environments.
1. Nitrile Rubber (NBR)
Characteristics: Good oil resistance, low cost, and one of the most widely used sealing materials.
Applicable Media: Petroleum-based hydraulic oil, lubricating oil, gasoline, water, etc.
Temperature Range: -40℃ ~ 120℃.
Limitations: Not resistant to ketones, esters, ozone, and strong polar solvents.
2. Fluororubber (FKM/Viton)
Characteristics: High temperature resistance, chemical corrosion resistance, excellent oil resistance, suitable for harsh working conditions.
Applicable Media: Acids, aromatic hydrocarbons, animal and vegetable oils, synthetic oils, fuel oils, etc. Temperature range: -20℃ ~ 250℃.
Limitations: Poor cold resistance; not suitable for ketones and low molecular weight ester solvents.
3. Silicone Rubber (VMQ)
Characteristics: Excellent high and low temperature resistance, good electrical insulation, non-toxic and odorless.
Applicable scenarios: Household appliances, medical equipment, food contact equipment (such as electric water heaters, water dispensers).
Temperature range: -55℃ ~ 250℃.
Limitations: Low mechanical strength, not oil-resistant, not suitable for concentrated solvents or concentrated acids.