Spalling or P.S.O. ? 2

[gearcutter]

Interesting article by R.L. Errichello, C. Hewette and R. Eckert on 'Point Surface Origin Macropitting'.
In his gear failure classes, Errichello calls this phenomenon a type of macropitting.
In his gearbox CSI classes, Drago calls this phenomenon spalling.

http://www.geartechnology.com/issues/0111x/errichello.pdf

Ron Volmershausen
Brunkerville Engineering
Newcastle Australia

http://www.aussieweb.com.au/email.aspx?id=1194181

 

[mfgenggear]

Nice Post Gearcutter

Mfgenggear
if it can be built it can be calculated.
if it can be calculated it can be built.

 

[CoryPad]

I took Drago's CSI class and am familiar with the sliding-induced shear mechanism he proposes for spalling. Interested to read more about the PSO theory.

 

[tbuelna]

Thanks for the link gearcutter. I only had a chance to give the article a quick scan (I definitely plan to read it through when I have more time), but from what I saw beyond the discussion of characterizing specific types of flank surface distress, the article also made some excellent points about how the problem is caused by geometry issues such as inadequate tip relief and/or lack of profile control just beyond the active surface in terms of fullness/hollow/slope.

Regards,
Terry