Posted by Brian Dengel- The Gear Forum on July 21, 1999 at 10:37:06:
In Reply to: Gear noise problem posted by Mark Lehnert on July 18, 1999 at 09:00:30:
I agree with all of the comments made by B Simpson. The critical components of noise are misalignment, contact area, lubrication and speed. By inproving each area, you will decrease the noise.
Misalignment is the most common problem. Tolerance build-up between the bearings, shafting, housing and gearing will either cause binding if too tight and noise if too loose.
The contact surface must be clear of all imperfections in order to minimize noise at speeds about 10,000 rpm. Grinding and lapping are two good methods. So is increasing the face width and/or using helical gearing to increase the effective face width. Pitting, scaling and burrs will all be amplified by the high rpms.
Lubrication is key. In order to operate a high speed gear train you need to use a lube that can dissapate the heat and minimize the surface wear.
As you increase the speed, you will increase the noise. Decrease the speed and the noise should reduce proportionally. If you take the precautions listed above, you can minimize the decibels, but you will not be able to run silent at 34,000 rpm.