Grease: Positive Lube System / Flow-through Lube

[electricpete]

On page 5 is description of Baldor / Reliance’s “Positive Lubrication System” for greased bearings which I believe is the same as a flow-through lubrication system:

http://www.baldor.com/pdf/literature/BR420_091708_WEB.pdf

Does anyone have any experience with flow-through greasing lub or this configuration in particular?

I am particularly interested for high D*N applications... 6313 at 3600rpm.

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[waross]

Hi Pete. I took it to be marketing hype. It looks to me as if it is a typical bearing with particular attention to the grease channels so that there is no mounting orientation that will cause the bearing to run out of grease.
Why not an e-mail to Baldor?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[electricpete]

I talked a little bit with a distributor, but he did not have too many answers.

I know Baldor/Reliance has done some research on greasing configuration since I have seen some papers from them.

This is also not the standard Baldor/Reliance configuration... it only comes with the top-of-the-line IEEE841 motors.

This is different than any of our motors in that the grease is directed into/near the bearing, rather than into a cavity.

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[elmotor]

This kind of lubrication arrangement has also been used in bigger motors from ABB and also in the past in Stromberg motors. Here the grease is not going through the bearing but only greasing the "outer" side of the bearing. With this arrangement the bearing temperature rise can be maintained below 50K/45K and while regreasing the temperatures will not rise so high as "standard" lubrication. PLS is just marketing hype.

 

[electricpete]

Thanks.

Regardless of exactly what you call it, the fact that temperature is lower would be a good thing for the grease life which imo is a limiting factor for 3600rpm machines with relatively large bearings.

What is it about this arrangement that helps it run cooler?



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[starkopete]

Hi,
From the 'for what its worth department'; The diagram looked familiar so I asked a couple of the senior techs in the shop and they said that Reliance has been using that particular design for years. I know that other motor manufacturers have used "flow through" arrangements but I don't recall them forcing the grease directly into the ball path.

Thanks

 

[rmw]

Be cautious when some vendor "touts" some advantage. Often they are using the reverse tactic of taking a weakness and presenting it as a strength - an old and common marketing trick (do the research on Verizon's network vs. AT&T's and understand who is presenting as a strength an actual weakness). ((And don't hijack the thread over Verizon/AT&T)).

I am not saying that this is a weakness, just that I am often suspicious of why any particular company promotes any particular feature, especially one as settled as grease lubrication.

Grease flows into the bearing and out and after a while the oil separates from the soap and the junk is pushed out by the injection of new grease which starts the process all over again. What's new under the sun?

rmw

 

[electricpete]

Starkopete - thanks. According to page 7/48 of the brochure linked above, it is a feature of only the IEEE841 model,

rmw - Other motors I have seen inject grease into the large open cavity and this one into a narrow channel directly adjacent to bearing as suggested here. That is new to me.

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