ISO 1238 and AGMA, tangential composite deviation

[mprice]

Hi Gear Experts!

I need to specify plastic gears for tooling in China. They work to AGMA standards whereas we work to ISO. Is the ISO 1328 quality class the same as AGMA?

And a second question, do I need to specify total and tooth-to-tooth tangential composite deviation in the gear table or is this unecessary if I specify ISO 1328?

Finally is there a formular to calculate tolerances for base tangent length over n teeth?

Any answers to any or all of these questions would be really appreciated.

Regards

Matt

 

[israelkk]

Depends on the AGMA version. The ISO 1328 should be the same as the new AGMA 2015. It is not the same as AGMA 390.03 or AGMA 2000-A88 (which is the same as 390.03). If you specify the AGMA Q number (for example: AGMA Q10C) the "tooth-to-tooth" and the "total composite tolerance" are already defined. However you will still need to specify the minimum and maximum "testing radius" aee AGMA 370.01 for guidance how to calculate the "testing radius".
Personally, I do write the "tooth-to-tooth" and the "total composite tolerance" in the table even though I specify AGMA 390.03 because, I have noticed that sometimes the manufacturer by nistake uses the older AGMA 390.02 which is different.