Four factors affecting the function of the bearing oil seal of the harmonic reducer
n order to give full play to the oil seal function of the harmonic reducer TIMKEN bearing, suitable materials must be selected according to the conditions of use. Let's take a look at the four factors that affect the function of the oil seal.
The surface linear velocity of the shaft: Under the same diameter, oil seals made of different materials have different ability to adapt to the linear velocity of the shaft surface rotation. The linear velocity range used by the oil seal is generally less than 15m/s, and good lubrication and good heat dissipation conditions are the decisive factors. Correspondingly lower data is suitable for more demanding conditions.
Four factors affecting the function of the bearing oil seal of the harmonic reducer
2. Temperature: Due to friction between the surface of the rotating shaft and the sealing part of the oil seal, the temperature of the sealing part is higher than the temperature in the oil. Generally, the temperature of the edge of the oil seal is higher than the temperature of the working medium by 20-50°C. As the speed increases, the pressure increases and the temperature at the sealing edge also rises. In addition, oil seals with dust-proof devices are 20°C higher than oil seals without dust-proof devices. When the allowable temperature is exceeded, the working life of the bearing oil seal of the harmonic reducer will be shortened, resulting in premature and permanent hardening of the sealing components, and increased wear. The working temperature range of the oil seal is related to the material used in the oil seal: -40~120℃ when the material is nitrile rubber (NBR), -30~180℃ for acrylic rubber (ACM), -25~300℃ for fluorine rubber (FPM) .
3. Pressure: The oil seal is mainly used for pressureless or micro-pressure conditions, and the working pressure is 0.02～0.05Mpa. When the working pressure exceeds this value, pressure-resistant oil seals should be selected.
4. Dustproof: In order to prevent pollutants, dust, and moisture from entering the sealed cavity from the air side, it is recommended that the bearings of the harmonic reducer use oil seals with dustproof devices. If the intrusion of pollutants is serious, it is recommended to use 2 oil seals, which are installed one after the other in series.