Regarding the issue of significant fluctuations in transmission bearing temperature?
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This post was last edited by lovestory on 2012-4-8 at 13:00. We have a device whose transmission bearing temperature sometimes experiences significant fluctuations; once it even rose by ten degrees Celsius before dropping again. These fluctuations are not ordinary and are quite dangerous – last time, it almost caused the vehicle to shut down! I checked the trends; the vibration first increased, followed by an increase in bearing temperature, while there was no significant change in other temperature readings! Could everyone analyze what the reasons are and what needs to be paid attention to?
1. First, check whether the contact of the hot spot resistor is good. 2. Does the high temperature occur under load variations? 3. Is there a possibility of the oil inlet being blocked? 4. The center distance on both sides of the large and small gears changes. 5. Are all the oil parameters within the standard range?
The vibration increases first, which indicates that excessive vibration has caused poor contact in the wiring of the temperature sensing probe, leading to a rise in temperature; once the vibration decreases, the temperature returns to normal.
Just to be safe, it’s better to open it and check.
What kind of equipment? Let’s start with vibration and find out the cause of it
Vibration is transmitted, and the vibration of the other point bearings will also change accordingly. What is the spectrum of the vibration? Axial or radial? Sliding bearings used in the gearbox? What causes vibration and high temperatures? The lubricating oil in bearings primarily serves to lubricate and cool. It may be that the lubricant is gradually losing its effectiveness (high temperature – cooling – high temperature...), or friction in the bearings is causing vibration or heat.
This post was last edited by A pot of fragrant tea on 2012-4-10 08:09. If the vibrations caused by changes in operating conditions of the machine are excluded, it is likely due to defects in the balls inside the bearings; these balls move both in rotation and revolution. When defects on the balls (pits, peeling) happen to align with the motion paths of the inner or outer ring, it causes vibration and temperature rise ； When the defect moves away from the path of motion as the ball rotates, vibration and temperature rise disappear; this is an initial phenomenon. Over time, once defects such as pitting appear on the raceways of the inner and outer rings of the bearing, vibration and temperature rise become normal. So it is still recommended that the original poster shut down the machine, conduct a thorough inspection, replace the bearings in a timely manner, and eliminate potential risks.
This situation that occurs occasionally actually doesn’t mean much; operating conditions, oil pressure, bearings or bushings, etc., can all cause it to happen. Many applications in the chemical industry involve high speeds, so shaft bearings are likely to be used. We specialize in gearbox production. You can add me on QQ: 839465022; we can discuss any issues together.
Consider this issue from the following aspects: 1. First, determine whether the bearings in the gearbox are rolling bearings, sliding bearings, or tilting-pad bearings； Are the bearings you are referring to thrust bearings or radial bearings? ? Detailed explanation 2: If the vibration is severe, what is the cause of this severe vibration? Can the vibration spectrum be used to determine whether the vibration is caused by oil film oscillation or oil film whirling, or rather by issues related to the quality of the bearing shells? Changes in operating conditions also have a significant impact on vibration; it is important to determine whether operation is under variable conditions ； 3. If the vibration is caused by the gear itself, it is also necessary to analyze whether the gear is engaging properly and functioning correctly ； 4. For problems like this, it is still necessary to rely on advanced spectrum analysis instruments or equipment to achieve better results with less effort