What are the hazards of excessive clearance between the bearing and the shaft?
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There is a multiple-choice question: If the clearance between the shaft of a water pump and its bearings is too large, it will ( ) A cause the bearings to overheat, B lead to internal leakage, C increase vibration. Please tell me which answer is correct; is answer A right? Please explain your reasoning – extra points for that
This post was last edited by zdl1966 on 2017-10-16 at 20:31. The vibration level increases; the vibration between the inner ring of the bearing and the shaft exacerbates the overall vibration.
An excessive gap will cause the inner ring of the bearing to fail to rotate, resulting in the bearing losing its supporting function. Heat is generated only when the gap causes the inner ring of the bearing to rotate intermittently, resulting in friction.
Vibration at C increases; the vibration between the inner ring of the bearing and the shaft exacerbates the overall vibration
The answer is definitely C: a large gap leads to vibration, while a small gap is related to temperature.
Running on the outer ring increases vibration and raises temperature
The answer is c: the bearing alignment is off, which increases vibration! If the inner ring is not fixed, it can easily cause the inner sleeve to shift!
In actual production, significant vibration occurs in the inner ring, and no noticeable increase in temperature was observed under thin oil lubrication. C is correct.
I think both A and C are possible; the C scenario is more apparent, while B is only likely to occur when both oil seals fail
It should be A; I’ve encountered a similar issue where the temperature of the bearing at the coupling end of the boiler feed pump was too high. Upon opening it, it was found that the inner ring of the bearing had worn out, and the high temperature caused the lubricant to become ineffective, resulting in the bearing seizing.