The noise problem during bearing operation is not only related to the manufacturing process, but also the selection of lubricating grease plays a crucial role. Lubricating grease, as an important component of bearings, directly affects the noise level of the bearings in terms of its performance. Bearing noise is actually the result of bearing vibration propagating in the air and being perceived by the human auditory system. Therefore, the key to reducing bearing noise is to minimize bearing vibration.
The core component of lubricating grease is base oil, whose properties not only determine the lubrication effect of the grease, but also have a significant impact on bearing noise. Among various types of base oils, natural mineral oils exhibit good noise reduction performance, especially cyclohexane based oils, which have slightly better effects than paraffin based oils. In contrast, the noise reduction performance of PAO synthetic oil is slightly inferior, while polyester oil is relatively poor. The viscosity of base oil is a key factor affecting the noise reduction performance of lubricating grease.
Research has shown that as the viscosity of the base oil increases, the noise reduction performance of the lubricating grease will be improved. This is because higher viscosity helps to form a thicker oil film, which better attenuates bearing vibration and reduces noise. However, the higher the viscosity of the base oil, the better. In low temperature environments, excessive viscosity may lead to poor fluidity of lubricating grease, which in turn exacerbates bearing vibration. Therefore, the viscosity of the base oil needs to be selected within a reasonable range, which is the conclusion drawn through extensive experiments and research.
In summary, the viscosity of the base oil of lubricating grease has a significant impact on bearing noise. Appropriately increasing the viscosity of the base oil can enhance the thickness of the oil film, improve the lubrication effect, and thereby reduce noise. However, the selection of viscosity requires comprehensive consideration of factors such as temperature and grease flowability to ensure smooth and quiet operation of the bearing.
