Finn Lassen wrote:

I had mounted my PSRU so that the oil input lines was on top (12
o'clock) and exit on bottom (6 o'clock).

It just occurred to me that it might be better to have the return line
at the 3 o'clock (or at least 4 or 5), so the gears will remain in a
"bath" of oil.

Pro's? Con's?

Finn

I think that might help.

Paul Lamar

Tom Kendall wrote:

Oooo!  Very possibly a very bad thing to do.

With any kind of gearing, but particularly with helical and especially
herringbone gears, you don't want to immerse the gears in the oil.  The
result is a lot of radial and axial loads as the gears turn into oil pumps
and actively force the oil out of the meshing gears at a very high rate.

In addition, immersion of high speed components in an oil bath will cause
foaming of the oil, which really messes things up.  Besides causing flow
problems and air binding the pump, even very small air bubbles entrained in
the flow can cause micro-dieseling when the oil is injected into high
pressure locations (like thrust bearings and journals).  Actually had this
happen on a big reactor coolant pump a while back.  What we ended up with
was burnt oil and no clue as to what could possibly have caused it!
Fortunately a regular oil analysis program caught it long before it could
have led to any damage.

I think PowerSport nailed it when they pointed out that you want your oil
spray directed at the gears as they come *out* of mesh in order to carry
away the heat.  The residual film of oil left on the teeth is sufficient for
lubrication needs when they go back into mesh.

I agree that is ideal.
Hard to do that with a six pinion planetary. You will need six
tiny sprays one for each pinion. I think the drain back is the key just 
like a turbo. Perhaps a half inch ID drain back pipe is called for so the foam is
carried away.

BTW Come on guys start putting your response on the bottom of the message if
you want to reference something that has been written before. 
This is the ACRE NL standard way!!!!

I am going to delete everything after your new message unless you start doing this.
This is too much work for me. Then you will have people asking you what
you are referring to :-) Makes more sense to me rather than having it 
up side down chronologically.

Paul Lamar

 
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