Oil Seal Material

The commonly used materials for oil seals include nitrile rubber, fluororubber, silicone rubber, acrylic rubber, polyurethane, polytetrafluoroethylene, etc.
Nitrile rubber (NBR)
It has good heat resistance and wear resistance, and is resistant to various lubricating oils, greases, oil gas mixtures, etc. It is suitable for temperatures ranging from -30 to 120 degrees Celsius, but cannot be used in phosphate hydraulic oils and gear oils containing extreme pressure additives. Its performance is stable in gasoline and low aniline mineral oils.
Acrylate rubber (ACM)
Excellent oil and heat resistance, wear-resistant, ozone resistant, UV resistant, especially resistant to lubricants, gear oil, motor oil, engine oil, petroleum hydraulic oil, etc. containing extreme pressure agents, suitable for working in the range of -30~150 degrees Celsius.
Fluororubber
Durable to aging, heat, and oil, it is almost suitable for all lubricants, fuel oils, and gasoline. It is not easy to harden in oils containing extreme pressure additives, but has poor cold resistance, high temperature wear resistance, and large permanent compression deformation. It is suitable for temperatures of -20~250 degrees Celsius.
silicon rubber
Has outstanding resistance to high and low temperatures, can be used for an extended period of time at 150 degrees Celsius without any performance changes; It can be used continuously for 10000 hours at 200 ° C and maintain its unique elasticity, ozone resistance, weather resistance, and other advantages within the working temperature range of -70~260 ° C.
Polytetrafluoroethylene
It has outstanding chemical stability, thermal stability, anti friction and self-lubricating properties, and its cracking temperature is above 400. Therefore, it can operate normally in the temperature range of -200 to 300 degrees Celsius. Except for free fluorine and alkali metals, it has excellent corrosion resistance to chemicals, solvents, hydroxide compounds, and acids .
Nitrile rubber and fluororubber materials are widely used oil seals. The former is low-cost, but has significantly improved temperature resistance and sealing performance. However, the cost is high, and it still has some common disadvantages of ordinary rubber materials, such as poor wear resistance, short service life, and special sensitivity to eccentric reactions of the shaft. Leakage phenomena are still quite common. PTFE oil seal is a product with high technical content and is the direction of future oil seal development.
When selecting the material for oil seals, it is necessary to consider the compatibility of the material with the working medium, adaptability to the working temperature range, and the ability of the lip to follow the high-speed rotation of the rotating shaft. During the operation of a general oil seal, the temperature of its lip edge is 20-50 ℃ higher than the temperature of the working medium. Attention should be paid when selecting oil seal materials. The working range of oil seals is related to the materials used: -40~120 ℃ for nitrile rubber (NBR), -30~180 ℃ for acrylic rubber (ACM), and -25~300 ℃ for fluororubber (FPM)