Help needed looking for sealed cartridge bearings

I am looking for cartridge bearing with contact seals that will do an adequate job of resisting rain and debris entry, as well as prevent low viscosity oil(no pressure behind the fluid) from getting escaping.

http://www.skf.com/group/products/bearings-units-housings/ball-bearings/deep-groove-ball-bearings/single-row-deep-groove-ball-bearings/sealed-bearings/bearings-with-contact-seals/index.html There is a table here that shows various bearing seals and sort of compares them. 2RSL, 2RS and 2RSH all have various degrees of sealing, there are other seals, and surely other seals sold by other companies, there is something of a wide selection and the problem is I have no solid way of knowing what is ideal for doing the job.

I am hopeful someone on this forum is knowledgeable on the subject of sealed cartridge bearings and can shed some light on this subject. What would be adequate for this application?

Thanks with a side of guacamole.

bowlofsalad said:

What would be adequate for this application?

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you make mention of resisting rain etc, but don't actually say what your application is.

I'd just try e-mailing either someone like SKF, or a re seller like Simply Bearings and see what they say.

NeilP said:

bowlofsalad said:

What would be adequate for this application?

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you make mention of resisting rain etc, but don't actually say what your application is.

I'd just try e-mailing either someone like SKF, or a re seller like Simply Bearings and see what they say.

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The application is electric bicycle hub motors. Some type of oil (Usually automatic transmission fluid) is put into an electric bicycle hub to act as a corrosion inhibitor, thermal transfer fluid, and a lubricant(in geared hub motors). I hope these words don't come off as overly specific or condescending.

To my surprise, I've e-mailed around 10 places, including SKF, NSK and various re-sellers, it's been 2 or 3 days and I have yet to get a single response. "Cast your net wide" Even if/when I get responses from them, I'd enjoy hearing what is said here. However, I've never heard of simply bearings, so I'll send them an e-mail and see what they have to say, thanks!

They are a UK bearing supplier, sorry, I somehow thought you were UK based.

So, you are after a bearing / oils seal combo to help keep the oil in as much as dirt and water out.

If you are building up your own custom motor with own oil fill spec, then it maybe just as easy to turn down your own side covers to fit a bearing and double lip seal arrangement,maybe with a spiral cut to 'pump' oil away from the seal.

If you are just using a standard motor and are after replacing the standard bearings and seals, what was /is the issue with the OEM ones that you need to put different /updated spec bearings ?

NeilP said:

If you are just using a standard motor and are after replacing the standard bearings and seals, what was /is the issue with the OEM ones that you need to put different /updated spec bearings ?

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Most(all, as far as I know) people who put fluid into a hub motor seem to have issues with fluid leaking in some way, one of those ways involves leaking 'through the bearing', an educated guess would be that most(likely all) of the cartridge bearings used have shields rather than seals, shields have a gap, contact seals do not. Even if a hub motor was claimed to include a contact seal cartridge bearing, unless I knew they were specing this seal with this application in mind I'd rather source the part myself with this application in mind. I almost settled on just buying a variety of types of contact seals and testing things, but that seems silly when someone might have enough knowledge to narrow things down a fair bit, at least.

That web store you suggested(simply bearings) has a fantastic layout, maybe the best I've seen in bearings and really great as far as web stores go in general. Nearly every place I've looked at for bearings has seemingly zero order or close to it.

What sort of oil depth are you using?

I would have expected not more than one third depth, certainly not totally full. I'd also consider fitting a breather hole at the top half of one of the side plates, to prevent pressure build up which would cause oil to be forced out.

All the hub motors I have taken apart seem to have a single lip oil seal, on the external side of the bearing, fitted to keep dirt out rather than fluid in.

I'd look at fitting a different, thinner bearing. - and /or redesigning the side covers, to allow fitting of an oil seal inside of the bearing, instead of a 10mm thick bearing, go for a 5mm one, allowing a 5mm seal on the inside, ..something along those lines..I did this, but it did mean making a new axle too, that was also thicker.

I was a mechanic for 45 years, everything from motorcycles to heavy equipment, and I have never seen an application that used that type of seal\brearing combo.
It might work, but a couple of questions come to mind. Will not they be wider than the brg. they are replacing? And what exactly will be the surface they will be in contact with. Also, are they directional? Will they pass the oil one way and in that case, would not the seal portion have to face inwards?
Every fluid retention application I have ever seen uses a brg. with a decicated oil seal.
In the case of these motors, that would require machining the boss deeper to recess the brg. and install a double lipped oil seal that would seal from both directions. Whether or not there is enough metal to do that is questionable. It would be a bummer if the machinist called to say he "struck daylight".

To me, when some one feels they need to put oil in a motor, really means they need a bigger motor.

motomech said:

I was a mechanic for 45 years, everything from motorcycles to heavy equipment, and I have never seen an application that used that type of seal\brearing combo.
It might work, but a couple of questions come to mind. Will not they be wider than the brg. they are replacing? And what exactly will be the surface they will be in contact with. Also, are they directional? Will they pass the oil one way and in that case, would not the seal portion have to face inwards?
Every fluid retention application I have ever seen uses a brg. with a decicated oil seal.
In the case of these motors, that would require machining the boss deeper to recess the brg. and install a double lipped oil seal that would seal from both directions. Whether or not there is enough metal to do that is questionable. It would be a bummer if the machinist called to say he "struck daylight".

To me, when some one feels they need to put oil in a motor, really means they need a bigger motor.

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I am no expert on cartridge sealed bearings, which is why I made this thread. However, to my understanding, you could hold a shield bearing and a contact seal bearing, and externally you wouldn't be able to tell the difference, they would be visually and dimensionally identical. I think the primary differences relate to their obvious pros and cons, better sealing, and to varying degrees more friction. There is an extremely high chance that you've been around, held and seen and installed countless cartridge contact sealed bearings and didn't know it. They are used in anything that shield style cartridge bearings are.

NSK has developed a shaft seal bearing, but it's designed for specific applications. A conventional sealed bearing's seal is only good for keeping grease in and dust out. They will bleed any liquid put against them.

Likely you'll need to adapt your motor for conventional shaft seals. I know the Clyte 5404 uses them, I think other motors do as well.

Looks like a 2RS closure is the best of the bunch: http://www.astbearings.com/bearing-closures.html