Gear drives requirements

[DocSergey]

Maybe someone knows gear drives (or speed reducers, or gearboxes) such as Nabtesco, Sumitomo . All their output parameters are similar, i mean torque rating, accelerating torque/ decelerating torque 250%, peak torque 500% and rating life about 6000 hours. Who knows standards (international or not) that defines requirements for gear drives of such class named above (like ISO/TR 13593 /// ANSI/AGMA 6113-A06 (Gear drives rated to this Technical Report shall be able to accommodate peak loads whose magnitude does not exceed 200%, so it's not what i'm looking for)) Maybe it is standard of the manufacturer and it's impossible to find it?
Thank u

 

[tbuelna]

You are correct that AGMA 6113-A06 guidelines for overload factor refer to AGMA 2101-D04 which uses a 200% momentary over-torque as baseline.

"For an overload factor of unity, this rating method includes the capacity to sustain a limited number of up to 200% momentary overload cycles (typically less than four starts in 8 hours, with a peak not exceeding one second duration). Higher or more frequent momentary overloads shall be considered separately."

AGMA 6113-A06 states the following regarding excessive overload conditions:

"Overloads. Loads which are in excess of the unit rating divided by service factor should be considered overloads. Overloads can be of momentary duration, periodic, quasi--steady state, or vibratory in nature. The magnitude and the number of stress cycles require special analysis to prevent low cycle fatigue or yield stress failure.

Standard industrial gear drives typically conform to the guidelines described in AGMA 6113-A06 or similar ISO standards. The AGMA standard actually does a pretty good job of optimizing components like gears and bearings so that they have balanced capabilities. While some adjustment of service/overload factors should provide reliable results in terms of predicted operating life, a big adjustment such as 500% vs 200% over-torque would not. In this case, a detailed analysis of all the components in the load path (gears, bearings, shafts, etc.) would be needed. If you have design details of all the components in the gearbox you could perform this analysis yourself. If not, I'm sure the gearbox OEM would perform the analysis for you if they are convinced it is a worthwhile business opportunity.