Bubbling of lubricating oil in the oil sight glass
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One of the high-voltage motors in our factory uses two babbitt bearings, one at the top and one at the bottom. Recently, a layer of bubbles has formed on the surface of the lubricating oil in the oil sight glass. The lubricating oil was changed not long ago, and there are no significant abnormalities in terms of bearing temperature or vibration, nor is there any unusual noise. Has anyone encountered this situation? Please share the reasons, possible causes, or solutions
In this situation, check what the oil temperature is. Generally, this issue occurs when the oil temperature is high and the exhaust condition is poor; a high oil temperature leads to the generation of smoke
1. Ensure that lubricant with the correct viscosity is used; generally, the higher the viscosity of the oil, the greater its tendency to form bubbles. 2. Ensure that the oil suction pipe of the lubricating oil tank is far away from the oil return pipe, so as to give air entering the oil return pipe a chance to escape—this is a design-related issue. 3. Check for the possibility of external contaminants, namely: dust, lubricant, or moisture. These pollutants prevent air from escaping from the bubbles. 4. Ensure that there are no air leaks at the suction side of the circulation pump; if there are leaks, air will be drawn into the oil. 5. Ensure that the system return oil path is below the fuel tank level; otherwise, the system return oil that sprays into the tank will also introduce air into the system—this is also a design issue. 6. Check the residence time of the lubricating oil in the tank to ensure there is enough time for air to be released.
I could only think of three possibilities: improper selection of lubricant, too high rotation speed of the pump, and short residence time of the lubricant in the tank. After reading the comments from the foam moderator upstairs, it clicked for me. :lol
Severe stirring can also cause the oil to bubble; over time, the oil will quickly emulsify and deteriorate
Bubbles can form if heat dissipation in the sealed oil chamber is poor; a breather hole can be added
Have it analyzed; if the values are within the normal range, there should be no problems.
Thanks for sharing, coming in to learn a bit*