View Full Version : About test radius of cylinder spur gear

13th Oct '11, 14:53
Could anyone sketch a drawing and show me the test radius of the production gear mesh with master gear?
Let me know how to calculate the test radius,I know AGMA 2000-A88,but can not understand.thanks.

4th Oct '12, 05:50
Depends on axle placements, and gear ratios that are required.

Ramana Rao
7th Oct '12, 10:37
There is no other method other than the one given in the Standard. Once you have brushed up your gear technology it becomes easy to understand what the Standard States.

9th Oct '12, 01:43
I am not sure I understand the question. If you mean testing a production gear to see its quality level, then the center distance (and the variation thereof) is what the tester is measuring. If it is an SAE gear then the distance is total teeth (both gears) / (2*pitch). but it will vary slightly with the inaccuracies of the production gear, and it will be smaller than the actual service distance since the tester loads them into close contact.

Ramana Rao
9th Oct '12, 06:35
Hi maniacal_engineer
The relevant AGMA standard gives procedure for testing production gears by meshing them with a master gear. Now the center distance to be set on the double flank testing machine has to be derived, which depends on the max. tooth thickness of the manufactured gear. From the measured tooth thickness, the actual pressure angle is calculated and the modified center distance derived. This derived center distance is the Testing radius stated in the standard and has to be set on the checking machine.