terminology "full complement bearing" 3

[electricpete]

What does that term mean?
(the context is anti-friction bearings).
Thx

 

[israelkk]

These are regular bearing but with no cage, thereby can have more balls inside and can carry more load. You can ask the bearing manufacture to supply the bearing you want as a full complement bearing.

 

[EnglishMuffin]

Full complement ball bearings are not common today in general industry, although they do often appear as thrust types. One place they do still show up a lot is in bicyles. Most full complement bearings are roller types. It might also be worth mentioning that full complement bearings usually have a much lower maximum speed rating.

 

[israelkk]

Full complement ball bearings are common in military and aerospace. Look in Barden Co. and MPB Co. catalogs.

 

[EnglishMuffin]

Well, it depends what you mean by "common". I always seem to get involved in these issues about semantics. My guess would be that even in the military and aerospace fields, the number of full complement ball bearings used would be a very small percentage of the total. But I stand ready to be corrected !

 

[diamondjim]

Full complement bearings have greater capacity
and require slow rotation and generally used only
in thrust style bearings. Most bearings are
not full comlement as Englishmuffin suggests.
Fifth wheel bearings is one example of
a thrust bearing with full complement of balls.

 

[EnglishMuffin]

Another place the full complement ball arrangement shows up is in rod-end bearings, which allows the rod-end to swivel in both directions, but that is of course a very low speed application. And of course the "full complement" term is also used in ball screws, which sometimes have reduced diameter spacer balls or even plastic spacers on some of the newer non-full complement types.

 

[electricpete]

Thanks guys, I appreciate all the help.

 

[Gerry45]

'Full complement' is a bit of a misleading term. In reality it just means that a bearing has more rolling elements in it than the normal one of the same external dimensions. In the majority of the 'standard' deep-groove brgs for example, the number of balls is limited by the rather convenient assembly technique called 'eccentric displacement'. If you want to get a few more balls in, one can make small cut-outs in the side faces (called filling slots) and fill the brg this way. But if you dont put in too many balls, there is still room for a cage. This gives more 'dynamic capacity', normal speed capability but reduced axial load capability. Such a brg is frequently called a 'full complement' type..... But you can go further, removing the cage will let allow you to pop in one or two more balls. Sometimes the term 'maximum capacity' is used instead of full complement but unfortunately its no more descriptive !

 

[diamondjim]

Often bearings have a filler plug
which allows a full fill of ball
and/or rollers. The conrad style
the gerry is talking about it
not defined as full complement
and only allows approx 1/2 the
rolling elements in it. Gerry's
reference applies to radial
style conrad bearings and not
to bearing in general.

 

[EngJW]

I think the term is most commonly appled to needle bearings, such as the Torrington drawn-cup needle bearings. They are full compliment when they are completely filled with needle rollers in the circumferential direction. The needles are not separated and can contact each other. The opposite of full compliment is caged, where the needles are separated by a cage which also holds them in alignment, preventing them from skewing and contacting. This permits higher speeds. The full compliment bearings work ok for low speeds and oscillating motion, and may have a higher load capacity.

John Woodward