New Ball bearing in 280 fr motor
New Ball bearing in 280 fr motor
(OP)
Hi Guys
Can anyone shed some light on this matter. We replaced both SKF 6317 ball bearings on a 280 frame 90Kw 4pl B3 motor on pump application with flexible coupling drive. This motor has been in service for 5 years and we replaced the bearings during routine service. The bearings were purchased prepacked with grease and heated to give a nice gentle fit. The chamber had the old grease removed and was 2/3 rds filled with new SKF grease. (gap as instructed to allow for expansion)When we put it back into service we gave it a quick run and then put in another 5 grams of grease. It ran fine for a few days but then began to get noisey on both ends. We gave another shot of grease and problem went for another few days and returned. What do you think the problem. Thanks for any replies.
Can anyone shed some light on this matter. We replaced both SKF 6317 ball bearings on a 280 frame 90Kw 4pl B3 motor on pump application with flexible coupling drive. This motor has been in service for 5 years and we replaced the bearings during routine service. The bearings were purchased prepacked with grease and heated to give a nice gentle fit. The chamber had the old grease removed and was 2/3 rds filled with new SKF grease. (gap as instructed to allow for expansion)When we put it back into service we gave it a quick run and then put in another 5 grams of grease. It ran fine for a few days but then began to get noisey on both ends. We gave another shot of grease and problem went for another few days and returned. What do you think the problem. Thanks for any replies.





RE: New Ball bearing in 280 fr motor
Was the greases added compatible with the grease pre-packed into the bearing itself? Do you know both types of grease?
What is the shield configuration?
Possibility of contamination with dirt?
Less likely maybe preload was not established correctly with wavey washer.
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RE: New Ball bearing in 280 fr motor
If the bearing does not have enough load force the balls will skid on the races producing noise and overheating.
As Epete say probably you omitted the axial preload spring or wave washer regularly on the non drive end. This preload will allow the balls to roll properly on the races. Check for a few mils of free axial displacement after assembly of the rotor shaft.
In my opinion, the best grease for a regular electric motor with ball bearings is a good Lithium base grease grade NLG2.
RE: New Ball bearing in 280 fr motor
RE: New Ball bearing in 280 fr motor
No bearings are not getting hot, running at 22 degs and 19 degs C at NDE. Yes C3 was used.
Regards
RE: New Ball bearing in 280 fr motor
RE: New Ball bearing in 280 fr motor
Fits, shoulder, cocked bearing, wavy washer - for none of those do I see any reason for a delay until sound occurs. But you never know.
I may be totally wrong but I just wanted to explain my thought process.
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