replacing a journal with rolling element bearing 1

[sabermostafavi]

Hi to everyone
I have a shaft with velocity almost 7000 which always attaches to it's upper journal and causes to fail. Now I want to change it with one or two rolling element bearings. I want some help to know if it is possible in such a kind of speeds and what's the procedure of changing?

Thanks

 

[sabermostafavi]

Dear Tmoose
Idler shaft rotates in two bearings. Upper bush and the other end we have mounted an angular contact ball bearing. In our design axial load direction is downward so an angular contact for lower bearing is proper. But with these wrong pairs of helical gears axial load direction is reversed So we have to use Maybe! Maybe! an angular contact bearing for up of idler shaft. And about filling slots, according to API 610 we can not use any filling slot for bearings in OH6 type of pumps. Myself suggestion for these amounts of forces is 22310 skf d=50mm D=110mm B=40mm C=220KN. However we must change the design and casting of upper membrane and change the upper bush with a rolling element bearing.

Sincerely
Mostafavi

 

[BrianE22]

If your redesign has the upper bearing taking all the thrust load then you might have trouble with your existing lower bearing (they usually need some thrust load to prevent skidding). I'd look at using another angular contact bearing for the upper bearing and having a way to preload the bearings axially.

You might want to run this by the supplier of your existing angular contact bearing.

 

[MikeHalloran]

Does the upper intermediate shaft journal just happen to properly fit the bore of an appropriate rolling element bearing? Bloody lucky if it does.

Is the existing lower intermediate shaft bearing a deep groove radial bearing, or is it an angular contact bearing? You have called it both. Do you know the difference?

If you can fit a rolling element bearing at the top, maybe you should fit a bushing at the bottom. Have you calculated the loads on both bearings in all directions, for the original design and for the screwed-up-hack design?



Mike Halloran
Pembroke Pines, FL, USA

 

[sabermostafavi]

Thank you all for your assistance.

 

[clay87]

Thank YOU for this entertaining discussion!