For double row bearings the distance of rows is defined by the contact angle. The distance between rows is then
For spherical ball bearings the conformity of outer race is defined as
So it is the ratio of radius and outer race diameter, which is 0.5 as standard.
The shoulder diameter of the outer ring is automatically limited by the width and the radius of the outer race. Still a larger value as the limit could be entered by the user. The life modification factor aISO is calculated for both rows separately.