Stainless Steel Tapered Roller Bearings

[MASSEY]

We use tons of tapered roller bearings, but our supplier does not manufacture stainless steel ones.

We can get stainless steel ball bearings - good quality, no problems.

I would like to try some stainless steel tapered roller bearings (SSTRBs). But I don't have time or money to waste on poor quality.

Do any of you currently use SSTRBs and if so, who makes them?

 

[negotiator]

What are your parameters, app., environment, dimensions,
send diagram for load appreciation. There are many outlets for bearings, and 'STAINLESS' is really an ambiguous description; where case-hardened is the ploy for tapered-roller bearings (RC 56-64), stainless must see lighter load
but is 'more forgiving' of contaminants (nicks & scratches showing)instead of shattering.

thestocksguy@hotmail.com

 

[MASSEY]

I agree Stainless is ambiguous, but it is meant to be because the parameters vary so much from application to application.

When Stainless Steel TRBs are requested, they always go into a product that has stainless steel components.

Currently we provide the stainless steel components, which by the way have load ratings far below our normal hardened steel, and apply special coatings to the TRBs so we "might" get the effect of stainless steel.

We still get requests for entirely stainless steel products - and we're stumped because we don't currently have a stainless steel TRB supplier.

To summarize: I am looking for a supplier that has been in business for ... say 25 years or more, whose name is known for its quality products, and who has reputation for being the best at what they do.

Bearing bore sizes of interest vary from .75" thru 5".

Thanks for your help.

 

[MASSEY]

I expect the BDRs and static load ratings to be lower than for steel TRBs. I just want to find a quality bearing made by a quality manufacturer.

 

[diamondjim]

Check out Timken Roller Bearing Company
in Canton, Ohio. They probably have a web
site.

 

[MASSEY]

All our TRBs are from Timken - tons and tons a year. A Timken sales rep, who is originally from Italy and now based in Chicago, bought me lunch last week. They do not make SSTRBs. They do coat with Aquaspex which purportedly provides protection similar to SS.

They are in the process of acquiring Torrington. This will make Timken the 3rd largest bearing manufacturer in the world.

I cannot find SSTRBs in Torrington's catalog or at their website.

Thanks for the guess, but I was hoping for personal experience.

 

[diamondjim]

Massey,
Timken did make ss tapered roller bearings
and they had a ss suffix after the part numbers
to indicate ss. I guess the market was such
that it became cost prohibitive. I worked
there moons ago in the engineering department.
Sorry if I threw you a curve.

 

[MASSEY]

No problem. Thanks for the info. - I wasn't aware of that.

 

[drclark]

Just curious if you were able to find a SS bearing supplier?

I am currently looking for SS tapered roller bearings or thrust bearings myself, with little or no luck.

We have specific underwater applications that require the use of stainless steels.

 

[MASSEY]

drclark,

No luck yet, we continue to use AquaSpexx coated bearings from Timken. They are coated for applications such as you mentioned. In fact they make bearing replacement kits designed specially for boat trailors or other very wet enviroments.

I found one supplier in China that will supply chromed tapered roller bearings, I have not obtained a sample and do not think I will persue one at this time.

If you do locate Stainless Steel Tapered Roller Bearings, please let me know.

Thanks.

 

[CovyUK]

I'm also on the lookout for a ss trb supplier. I've yet to find one.

I'm about to get a sample of the Aquaspexx you mentioned. Do they perform well? I shall be fitting them to boat trailers, which go in and out of salt water regularly (lifeboats and beach rescue).

I hear Timken did make SS bearings but as dimondjim says, but they weren't cost effective for the negligible improvement in performance.

I'd appreciate any advice,

Cheers,

 

[ccw]

Massey and others,
Good luck in your search for TRB's in stainless. I made the same search last year. 99.9% of the worlds bearings are made from 52100C steel which rusts rapidly without some coating protection. Most coatings offered wear off after some time in service due to high contact stresses.

440C is the "stainless" material in most of the smaller ball bearings and works well, requiring no coating and offering good corrosion resistance and life. But, it is apparently not a usable material in the larger sizes and in the TRB's.

FAG/Barden/Germany offers a proprietary process called "Cronidur" which they claim has the corrosion resistance, life, and performance of 440C. They make this process available for the larger sizes of bearings including roller bearings. These units are expensive relative to the 52100C counterparts.

 

[Hippo41]

If your application is boat trailers, try changing the grease to something like an overbased calcium sulphonate (TOTAL FINA CERAN HV or similar). This does not emulsify easily with water (like normal greases do) and I have used this with great success launching ski-boats into the sea off Durban.

Stainless generally too soft to make bearings, it's expensive and difficult to work. However, there are specialists who will make ball, and cylindrical roller bearings in stainless (generally small, private workshops - not the 'big guys'), but not tapered rollers.

Have you got a definite requirement?


Lester Milton
NBC Group Ltd, Telford, Shropshire, UK

 

[CovyUK]

Cheers Lester,

I've got my hands on some samples of grease which I'll be putting on trial shortly. Not sure what these comprise of but are supposedly tailored for aquatic environments.

I think one is by Fuchs and called Renolit Aqua 2 or XL or something. The other is by Rocol and called Sapphire Aqua 2.

I'll post details of how well they performed.

Andy
RNLI, Poole, UK

 

[Hippo41]

I know them both - if you want some of the other for testing let me know. We are on the internet!

Lester Milton
NBC Group Ltd, Telford, Shropshire, UK

 

[MASSEY]

Timken's AquaSpexx coating was originally designed for boat trailors as a bearing replacement 'package'.

We've used some AquaSpexx coated bearings that are supplementally treated with MicroPoly or CobraLube. The solid lubricants do not break down under water. They can be used in submerged conditions and CobraLube has the added benefit of temps. up to 500F.

I am still looking for Stainless Steel TRBs although not as ardently as before because I have come to believe that they do not exist.

 

[abdul]

Massey,

I think you have an interesting problem, and in fact, I once had a boat trailer with heavy corrosion on the roller bearings of the wheels. Here is one solution:instead of installing stainless steel bearings to resist the leakage inward of corrosive water, why don't you use standard roller bearings, and modify the bearing housing so that simple mechanical face seals are used to seal out the water.You will only need one seal per bearing, if designed properly.

The seals can be low cost off-the-shelf that are normally applied to centrifugal pumps. In addition, I would imagine that your boat trailers are using automotive parts for the bearing holder. I would advise modifying these if possible, to accept externally mounted simple carbon face mechanical seals. Of course, the grease will still be packed inside this chamber, however, now, the water will not be able to leak in. In addition, on the road, the resulting dry friction of the seal faces is negligible due to the face velocities.



abdul

 

[MASSEY]

Thanks abdul,

We got talking about boat trailors cuz of AquaSpexx and like coatings, and someone posted a question about boat trailor application somewhere above. However, I am searching for SS TRBs to put in SS products that the company I work for produces and markets.

I do have a couple boat trailors but they are not exposed to salt water and I just use the spring loaded dust covers with a grease fittings installed. I just add grease when they need it and don't worry about them.

My search for SS TRBs has nothing to do with boat trailors.

But your idea is a good one and one I would try if I had a problem with boat trailors.

Thank you,

 

[Hippo41]

Massey

Does your bearing have to be a tapered roller? Ball bearings are commonly available, and there are also the mounted ball bearing units in thermoplastic housings?

Would either of these suit your needs?

We are currently manufacturing some special cam followers in stainless for a sugar mill application, but they are horribly expensive! We could probably look at making some cylindrical roller bearings in stainless, but i would shy away from tapered rollers bearings.



Lester Milton
NBC Group Ltd, Telford, Shropshire, UK

 

[CovyUK]

Just a quick update on my problem. I've taken to the idea of finding a suitable seal for the hubs, rather than look for a corrosion resistant bearing.

Any bearing given time will corrode if (in my case) salt water enters the wheel hub. So I plan to prevent that from happening. Have found a couple of manufcaturers (John Crane - ProTech Bearing Isolators and SKF).

We make our own phosphor-bronze bearings for launch trailers as they aren't towed on the road. But for road going trailers this would be illegal, so we use the standard trb's. Depending on the application, ball bearings might work just as well (providing the thrust loads aren't prohibitively high).

I also looked at plastic bearings from WYKO, but these were ruled out as the shock loads from towing the trailers over rough ground would simply destroy them. But they might suit other applications.

SKF manufacture stainless ball bearings units. Might help!

Andy Covington
RNLI