# What does it mean that a ball bearing can handle thrust load but a roller bearing can't?

I can't wrap my head around it so if someone could explain this to me. According to http://www.vncbearing.com/roller-bearings-vs-ball-bearings-major-differences/ ball bearings can handle thrust loads but roller bearings can't. Now I understand that ball can rotate around all axis and roller around only one, but still... If you put a shaft on those bearings it's meant to rotate, you don't allow a shaft to go through a bearing, it's always fixated in one way or another. So what's really the point of that statement?

• Think of the difference between the ball and the track it runs on and the rollers and the track they have... – Solar Mike Apr 7 '18 at 13:09

if you look at a ball bearing in cross-section, you will see that the balls are assembled into the two races in such a way that the races have side walls against which the balls can press as they roll. this means that a thrust load on one race will be transmitted through the balls to the opposite race without tending to push the races apart and open up the bearing. note that to assemble the bearing, one of the sidewalls on one of the races has to be missing its sidewall so the balls can be inserted between the races, so the bearing's ability to sustain thrust loads in one direction will be limited by that. But a roller bearing's races do not have sidewalls that can carry thrust loads without scuffing the ends of the rollers against other parts of the bearing and thereby galling and/or grinding those parts into failure.

• There is also friction in the roller bearing... – Solar Mike Apr 7 '18 at 19:42
• of course, but not the scuffing and abrasion you get when the end faces of the rollers engage other nonrotating parts of the bearing assembly.. – niels nielsen Apr 7 '18 at 19:50
• Just that it is not clear given the way you phrased your answer... – Solar Mike Apr 7 '18 at 19:53
• will edit now for clarity – niels nielsen Apr 7 '18 at 19:56
• Your ball bearing assembly description is incorrect. Ball bearings are assembled with the races ground, polished, and fully formed. Rather, it is the ball retainer that keeps the bearing from falling apart. The retainer keeps the balls evenly spaced between the inner and outer races. If the retainer is removed, the balls can tightly pack together on one side, and the center ring moves sideways into the open gap on the opposite side that the balls have vacated. The side where the balls are grouped together opens up, and the balls can be removed. – Dale Mahalko Apr 9 '18 at 23:08