Temperature rise in gear oil

I Know for a fact that high speed gears might have heat generation in the 15 % area, witch means in your case 300 x 0,75 x 0,15 = 33 kW.
I remember these values from a job together with a MAAG (Svitserland) representative a few years back because this meant 3 MW heat right down the drain from the 20 MW Gear.

Best Lars

I would think the type of gears would greatly effect the heat output. Viscosity of lubricating oil and the type used will also effect temperatures.

Thanks Lars and Michael,

I have a little more input.

There are about 30,000 of these systems in existence, with many different motor/gearbox combinations and sizes, usually around 100 to 200 Hp. The output shaft speed is usually around 65 to 140 RPM. The gear oil is usually an EP based AGMA #4. Some gearbox manf's state that normal operating temp would be 200 DegF Max with just air cooling. These end users must overload them, because they get much hotter, and this leads to premature failures.

My challenge is to design a universal oil cooler for all of them! I thought the gearbox mfgr's would have some charts or formulas on load or torque vs heat output in BTU's/Hr, So we would better know how much heat we need to get rid of. So far, I can't find any data like this. Has anyone seen any data on this?

Ken