Contact stresses two rollers in contact.
When a roller is in contact with a flat surface a line contact is obtained, giving a rectangular contact area of very small width formed, the size of the area depending on the load and materials.
E1, 2 = Young's modulus
F = load
r1, r2 =radii
v = Poisson's ratio
Two roller in contact
Mechanical Engineers Data Hanbook, James Carvill 1993 Page 52