Surface Factor Cs in Spur Gears

Reduction in endurance limit due to surface finish (steel parts).

Hardness (HB)

Tensile strength Su (ksi)

where:

A - Mirror-polished.

B - Fine-ground or commercially polished.

C - Machined or cold drawn.

D - Hot-rolled.

E - As forged.

F - Corroded in tap water.

G - Corroded in salt water.