Weird bearing failure mode
Weird bearing failure mode
(OP)
I've just witnessed a ball bearing failure that I've never seen before. The ball elements failed (not either race). They appeared to crumble. They were split open in two or more pieces each with a brittle looking fracture surface. It was on every ball. This happened at very low life. It is a standard size ball bearing from a "non-elite" supplier. The pieces are out to a met lab to see if it was a material issue, but I am wondering if anyone has seen anything like this. I know there will be in interest in more application info and pictures, but I have to be careful in what I post, so I'm starting with the question of if anyone has seen anything like this and what was the root cause?





RE: Weird bearing failure mode
http://maintenanceforums.com/eve/forums/a/tpc/f/37...
http://maintenanceforums.com/eve/forums/a/tpc/f/71...
As I recall several times that symptom was also associated with craters on the balls. I had some discussion of possible connections here:
http://maintenanceforums.com/eve/forums/a/tpc/f/37...
I surmise that craters can be a brittle failure pattern, just like splitting open. Both related to ball properties. Either a result of manufacture, or some change resulting from operating conditions (chemistry, temperature, long-shot would be electric current). At least that's my broad vague swag on the situation.
=====================================
(2B)+(2B)' ?
RE: Weird bearing failure mode
http://web.applied.com/site.cfm/Bearing_Failure_An...
======================
slightly different explanation from SKF here -
http://www.mromagazine.com/features/the-strange-ho...
RE: Weird bearing failure mode
"If you don't have time to do the job right the first time, when are you going to find time to repair it?"
RE: Weird bearing failure mode
=====================================
(2B)+(2B)' ?
RE: Weird bearing failure mode
Walt
RE: Weird bearing failure mode
RE: Weird bearing failure mode
I think you got it right. When we've seen this failure in the past it was from poor heat treatment.
If the balls are shattered and the rings are as well, then look at impact loading. If the balls are shattered and the rings look almost new then there is most likely something wrong with the balls.