Oil seal is the customary name for general seals. It is a mechanical element used to seal grease (oil is the most common liquid substance in the transmission system, and it also refers to the general liquid substance). It separates the parts that need to be lubricated in the transmission parts. Isolate from the output parts so as not to let the lubricating oil leak.

Oil seal is generally divided into single type and assembly type, assembly type is the skeleton and lip material can be freely combined, generally used for special oil seal. From the sealing function, characteristics, structure type, working state and sealing mechanism of the oil seal, it can be divided into various forms and different names, but it is customary to call the rotary shaft lip seal ring oil seal, static seal and dynamic seal (generally reciprocating motion) The seal is called the seal.

The representative form of the oil seal is the TC oil seal, which is a double-lip oil seal with a self-tightening spring covered with rubber. Generally speaking, the oil seal often refers to this tc skeleton oil seal.

Material of oil seal: Common materials of oil seal are: nitrile rubber, fluorine rubber, silicone rubber, acrylic rubber, polyurethane, polytetrafluoroethylene, etc.

Nitrile Butadiene Rubber (NBR)

It has good heat resistance, wear resistance, resistance to various lubricating oils, greases, oil and gas mixtures, etc., applicable temperature -30~120 degrees Celsius, but can not be used in phosphate ester hydraulic oil and gear oil containing extreme pressure additives, stable performance in gasoline and low aniline point mineral oil. [5]

Polyacrylate rubber (ACM)

Superior oil resistance, heat resistance, wear resistance, ozone resistance, ultraviolet radiation resistance, especially resistance to lubricating oil containing extreme pressure liquid agent, gear oil, motor oil, engine oil, petroleum hydraulic oil, etc., suitable for -30~150 degrees Celsius range.

Fluorine rubber

Aging resistance, heat resistance, oil resistance, almost applicable to all lubricants, fuel oil, gasoline, oil containing extreme pressure additives in the oil is not easy to harden, but the cold resistance, high temperature wear resistance is poor, permanent compression deformation is large, suitable for temperature -20~250 degrees Celsius.

Silicone rubber

It has outstanding high and low temperature resistance and can be used for a long time at 150 degrees Celsius without performance change. It can be used continuously for 10000h under 200 temperature, and can maintain its unique advantages such as elasticity, ozone resistance and weather resistance in the working temperature range of -70~260.

Teflon

It has outstanding chemical stability, thermal stability, friction reduction and self-lubrication, and its cracking temperature is above 400. Therefore, it can work normally in the temperature range of -200~300 degrees Celsius. In addition to free fluorine and alkali metals, the chemical products, solvents, hydroxyl compounds and acids have excellent corrosion resistance.

Nitrile rubber and fluorine rubber materials are widely used oil seals. The former has low cost, but the temperature resistance and sealing performance are significantly improved, but the cost is high, and it still has some undesirable commonalities of ordinary rubber materials, such as poor wear resistance, Short service life, particularly sensitive to eccentric reaction of the shaft, etc., leakage is still relatively common. PTFE oil seal is a kind of product with high technical content, which is the development direction of oil seal in the future.

When selecting the material of the oil seal, the compatibility of the material to the working medium, the adaptability to the working temperature range, and the ability of the lip to follow the rotating shaft at high speed must be considered. Generally, the temperature of the lip when the oil seal is working is 20~50 ℃ higher than the temperature of the working medium. Attention should be paid when selecting the oil seal material. The working range of the oil seal is related to the materials used in the oil seal: when the material is nitrile rubber (NBR), it is -40~120 ℃, Acrylic rubber (ACM)-30~180 ℃, and fluorine rubber (FPM)-25~300 ℃.

Oil seal is the customary name for general seals. It is a mechanical element used to seal grease (oil is the most common liquid substance in the transmission system, and it also refers to the general liquid substance). It separates the parts that need to be lubricated in the transmission parts. Isolate from the output parts so as not to let the lubricating oil leak.