Checking from SKF calculator, at www.skf.com - Calculations - Bearing life

Assuming 16x22x20 needle bearing on v=12 oil (SAE30@100C) with nc=0.5

300 hp - 4.0 kN force (887 lb), 9100 rpm, gives L10h=260h L10ah=320h

200 hp - 2.7 kN force (591 lb), 9100 rpm, gives L10h=950h L10ah=1130h

160 hp - 2.1 kN force (473 lb), 9100 rpm, gives L10h=2190h L10ah=2600h


So, if assumptions are on the right side, 20B engine could be just too
much for an E40D unit.

Cheers,
Petri

One can always take the steel needles out and replace them with silicon
nitride as used in 30,000 RPM machine tool spindles and Formula 1 cars.
They are ten times better :)


Paul Lamar

Yes, that's right. But 6x ceramic bearings.... :)

You have a photo with dimensions of couple of 3-4 planet E40D units.
http://www.rotaryeng.net/Four-Ford-planet-carriers.jpg
There's stated 0.535 to 0.685 in for pinion dimensions. That's rather
small... what you think is the pinion shaft diameter of 6-planet unit ?

But, our golden reference, Bell 47 planetary PSRU - has needle bearings
too. Or should we say "long rollers"?
http://www.rotaryeng.net/Bell-47-planet-carrier.jpg
We don't need to suspect anything with this unit - it has really proved
itself. But then again, dimensions are really different...

Cheers,
Petri

.45 inches shaft on the six planet unit.
The planets themselves are 1.2 inch OD.

Paul Lamar