Bearing installation direction?

[brollona]

I know that this forum exist from the down of the time and that it has more members than overall population of our planet, so maybe this question was asked already many times, or it is just basic thing that everybody knows except I missed it. So forgive me for this rudimentary question.


Why are bearings (and some other symmetrical parts, O-rings for example, metal gaskets...) always installed with serial/type numbers towards "outside", a visible side of shaft? Simple example are the most common ball bearings which are symmetrical and do not carry axial load, just radial. By some mine logic, the reason for such way of installing is just that bearing model number is visible without taking the bearing out of the housing/shaft. But some mine coworkers are claiming that it's not the same, that it will cause "problems" or "issues" , but nobody managed to explain to me which one.

Extra confusion bring some manufactures who put numbers on both sides.


Couldn't find anything online regarding this.

 

[hallboyone]

It is my understanding that, for standard ball bearings, the number facing out is simply a courtesy to the next guy.
Obviously, bearings meant to take thrust in the axial direction (such as taper bearings) will have a direction.

 

[bradleykd]

So long as the bearing is truly just a radial ball bearing, there is no problem or issues associated with installation direction - labels out is best practice for quick repair.

A lot of times there are angular contact bearings that look almost exactly like a radial ball bearing (to the naked eye - obviously different when measured) that have a required direction that has nothing to do with the part number position.

 

[Notgrownup]

When I installed my camshaft bearings on my Harley-Davidson, the instructions said to install with writing facing out but, looking at the bearings, they seem to have a flatter spot on the back side but they were radial bearings, I obviously followed instructions as all men do very well...never had a problem. I froze them the night before and they went in with very light taps.
Somebody did tell me that the writing on the outside was a practice to help the next one servicing the machine or motor.

 

[DFB]

Well all I know is once before I had to knock out the races on a hay wagon at work to find the part # located on the "back side" to match the bearings

So ya it be nice to orient them numbers out

 

[brollona]

It looks that we have same thoughts on this. Also, I checked few manufacturer sites, like SKF, Koyo. They have plenty info on how to remove/install bearings, but not a single word about numbers and orientation. So I think that only confirms that number orientation is just a urban myth.

 

[rsanter]

With ball bearings, sometimes there is a rubber seal on one side and just a steel shield on the other.
Sometimes it matters which one is what way. If it’s the same shield on both sides I don’t see how it matters

 

[Lwel9226]

It is my understanding that, for standard ball bearings, the number facing out is simply a courtesy to the next guy.

I always try to build things with the thought that some poor sucker will have to work on it in the future....
and that poor ******* might be ME....

LynnW

 

[duc916]

Like most have said it depends on the bearing type. On a bearing with a inner and outer race make sure to always push on the race that is getting the press. If not you can Brinell the race (small indentions in the race from the balls) and cause failure. For a drawn cup needle bearing (like the camshaft bearing mentioned) there is a thicker flange on the side with the part number, which is the side you need to press on or you can crack the bearing shell.

 

[Two Door]

A wheel bearing with imbedded magnetic strips for the ABS most definitely has to be oriented a certain way, although I can't tell you off the top of my head which marking goes where. But if it is wrong, the ABS won't work.