Where to Buy High Speed Ball Bearings 80000+ rpm 1

[mamba76]

Hi all. Im working on a diy project for a super charger. I need to purchase some high speed bearings capable of 80,000+ rpm. I know SKF make super precision anguler ball bearing for this but I am clueless of where to actually purchase these! I gotten a headache searching for days now. Or if anyone can think of a low cost solution thats already available? These must be a mechanical bearing of some sort, not oil, air or manetic. I know they are found in nummerous apliances and power tools. Myonic make ball bearings for the new turbos, but is there a budget way of getting my hands on something like this for a small load?

 

[mamba76]

Thanks for that and that sounds about what I would expect. I could live with that tbh lol. I got VE at 78% so more like 4hp so Ill accept that fuel efficiency must suffer. It it simple enough to bypass the supercharger or possibly dissengage it so then were just talking minor parasitc loss.

I made an excel sheet couple years ago that to calculate exhaust gas volume at varying mg of fuel. I wanted to know if the top end was suffering due to the AR size. Estimating the maximum injector flow at 70mg per stroke (standard injectors), engine speed 5500rpm, I would need 338cfm of air for complete burn which would require a boost if 22.1 psi. Exhaust flow would be 1325cfm (900F), thats as far as I got.

 

[Tmoose]

"High speed ball bearings" have some internal features that help them survive at high speed.

If the supporting shafts, housings, bearing abutments and shoulders, properly created to the required high precision and accuracy are not "purchased" at the same time, the bearings become low speed bearings.
Pages 5 and 8 and 13 here -

https://www.schaeffler.com/remoteme...ownloads_24/barden_bearing_failures_us_en.pdf

 

[gruntguru]

Start with this:

https://www.engineeringtoolbox.com/horsepower-comp.

. . . .
. . . . . . . That calculator unfortunately wants old English units,

I use this one a lot. Still need to convert flow to kg/s.
Link

je suis charlie

 

[mamba76]

Thanks for the links. I know I can make the air and will work out more precisely when the time comes, at the moment Ill concentrate on the bearings and shaft. I would like to somehow machine some permanent magnets on a 4 - 8mm shaft, maybe one with 2 poles and another with 4. If I dont use these in some sort magnetic design at least I could use them to test the bearing speeds by using a hall sensor and oscilloscope that I have. I can test the heat that they generate but I think theres more ways than just heat that can destroy a bearing so will read through Tmoose's docs.

 

[MacGyverS2000]

Heat doesn't do great things for magnetism, either...

Dan - Owner

http://www.Hi-TecDesigns.com

 

[Kim_W]

You can contact Schaeffler, SKF, for high speed bearings.
But high speed bearings are usually small because of the inertia of the balls. I used to work at Turbocharger R&D department in Japan, for a well known company. The speeds we were dealing with were 300.000 RPM plus...
You can use ball bearing or journal bearings, but depending on your application (no heat for example) you may opt for a very different bearing system.
After all, each bearing system has its own pros and cons.

Best regards,
Kim W

 

[mamba76]

Thanks for you input Kim. Sorry for the late response but I may revisit this topic sometime so wanted to say I appreciate your input. With my intension as a super charger the bearing would support minimal mass. i estimate the whole rotor assembley to be 1/5th of the weight of a comparable traditional rotor (iron turbine not needed) also it would be isolated from any direct heat contact other than the ambient tempereture under the cars bonnet. Using a magnetic coupling would add no additional force on the driving side of the rotor. So with enviromental temperatures, max speed and mass known it hopefully should be possible to find a bearing for this application.. or am I missing thrust as an attribute? 2 atmospheres (at least) almost constantly on the compressor side of the assembly?

 

[SwinnyGG]

You're definitely missing heat as an attribute. The temperature of the compressed air being generated by the compressor wheel will not be the same as ambient air temperature. It will be much, much higher, and that heat will soak the compressor wheel, housing, and anything attached to them. Will it be as hot as the turbine side of a turbocharger? No- but 100 extra degrees matters when you're trying to design a bearing to last indefinitely at very high speed.