Detailing drawing depicting retaining ring grooves designed to retain a ball bearing

[Life is a bowl of problems]

I am wondering what the accepted method for detailing retaining ring grooves on a shaft or in a housing, with the purpose of locating a ball bearing axially.

Are the inner faces of a pair of grooves, which are meant to retail a bearing between them, set at the nominal bearing width? Wider to provide additional clearance? Narrower to reduce clearance built into the proscribed groove width? (the groove width being wider than the ring thickness)

And secondly what's the best way to dimension the relative location of these groove? Outside to outside, Inside to inside?

Any insight / opinions are appreciated.

 

[SwinnyGG]

The answers to all of your questions depend on the function of the bearing in the system you are designing.

You need to evaluate your tolerances and how they stack, and the resulting effect on the position of the bearing, like you would for any other feature.

 

[Tmoose]

"Are the inner faces of a pair of grooves, which are meant to retail a bearing between them, set at the nominal bearing width?"

Those ring groove faces can't really secure the bearing race in any way. The outermost groove faces are the ones that would limit the axial motion of the bearing in each direction.

Also note that ball bearing outer races have radiuses. Those radiuses limit the axial capacity of the snap ring.

https://www.smalley.com/ring-design/load-capacity

 

[Life is a bowl of problems]

Tmoose,
Thats right but you need to allow for locational tolerances to ensure that there is room to install rings with bearing in place. I can calculate tolerances and come up with a theoretical distance but thought that there may exist a rule of thumb that consistantly works that's more direct.

 

[Tmoose]

Without more specific info RE: your arrangement and any actual axial location requirements, and potential axial loads, answers must be WAGs. Not prudent for design porpoises, or efficient for the folks willing to respond to posts.

The bearing width is likely to be X nominal, plus 0.000" - a little bit. Say -0.005" not knowing bearing size. But in actuality more consistent for name brand bearings.

If you are using Truarcs, Spirolox etc the ring width is likely to be pretty consistent. Nominal +/- 0.003 inch maybe according to the catalog, but in actuality more consistent.

So If the dimension to the ret ring groove outer walls are dimensioned = bearing width + 2X nominal ring width + 0.007" / + 0.009" It would always be assemble-able.
The width of the ret ring grooves can run pretty wild as long as the outer walls are in the "right place", correct OD/depth, perpendicular to the bore, have proper corner radiuses, etc.
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It sounds like the bearing will be installed in the housing with retaining rings on both sides. This suggests the possibility you are planning the shaft rotor may be a slip fit in the bearing bore. For the common arrangement of rotating shaft and stationary outer ring the shaft MUST be a tight fit in the bearing bore as is typical electric motor, pump, etc practice to ward off certain bearing creep and shaft wear.

The loading of the bearing // may // make it necessary to use an interference fit with the housing bore, which can mighty inconvenient for assembly. Nonetheless, Retaining rings are not a replacement for an interference fit, if that is what is needed.

 

[3DDave]

There are bearing retaining liquids that can substitute for retaining rings and press fits, avoiding the problems entirely.

Past that, how does one need a short cut from adding a few numbers together? What step could one skip in that process that would be a valuable time saver?

 

[sreid]

Beveled Snap Rings.

https://rotorclip.com/newsletter1014.php

 

[Life is a bowl of problems]

sreid,

Link appreciated. Thanks

 

[SwinnyGG]

.....even with a beveled snap ring, you still have to correctly calculate groove sizes and positions. Implementing a beveled snap ring on every assembly you build would be a pretty terrible band-aid.

 

[sreid]

More "Band-Aids."

https://www.jegs.com/p/Loctite/LOCTITE-Bearing-Mount/2342113/10002/-1

http://www.usatolerancerings.com/

 

[Michael-Lu]

http://www.bearingkingdom.com/