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Gear Lubrication Question

Gear Lubrication Question

Gear Lubrication Question

(OP)
Hello,

I am beginning to order parts for the building of a machine used to demonstrate machine vibration phenomena in an academic setting. A motor drives 2 shafts on each side via spur gears. The motor gear has 70T, Pitch diam 175mm, the second gear 26T, pitch diam 65mm and the third 25T, pitch diam 62.5mm. The motor will run at a max speed of 750 RPM, resulting in a pitch velocity of 6.9 m/s. For this speed, the gear manufacturer recommends splash lubrication. The gears are all sealed in by an oil pan and the large gear dips into the oil as it rotates. The gears are extremely lightly loaded (horizontally), and they are only turning shafts with imbalanced discs on them. This device will be operating in a classroom, so ambient temperature will be around room temperature. My questions are the following:

1)What type of oil and viscosity rating (ISO) would you guys recommend for the application and why?

2)There are two hex cap screws that attach the oil pan to a housing, and the screw holes are located in the lower part of the oil pan (not submerged, still above the oil level). I need to seal them with some type of washer. I have read that copper washers can react negatively with certain types of oils. Would plastic washers be ok? Or what would you guys recommend to seal the screws? The oil pan is made of 6060-T6 Aluminum.

3)Finally, I am using V-Rings around the shafts to seal the holes where the shafts enter into the oil pan, (again these are not submerged, only used to keep any splashed lubricant from coming out of the pan).  I have read that the available rubber materials can also react with different lubricants. The material choices are Nitrile Rubber, Hydrogenated Nitrile Rubber (for resistance to sulfur present in hypoid oils) and Fluorinated Rubber. What would you recommend based on the oil recommendation above?

Thanks so much for any input.
 

RE: Gear Lubrication Question

How much HP are we talking here?  I'm envisioning something that's maybe 1/4hp turning some small discs.

Then, academic setting says to me "very intermittent use".

So I'd say some cheesy nylon gears would run forever, dry.  And this device sounds like the antithesis of KISS.



 

RE: Gear Lubrication Question

1. SAE 30 non-detergent motor oil.  Because it is cheap, available anywhere and more than good enough for a low-load, low-speed, low-duty application.

2.  Dowty washer.

3.  Nitrile / Buna N

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