Traction rollers, line contact (Hertz)
Increase in maximum subsurface stress and matching decrease in allowable normal load for Hertzian LINE-contact rollers (parallel cylinders) under a given traction coefficient Ftan/F.
Increase factor, maximum stress under traction, τmax/pm(μ=0)1
Decrease factor, maximum normal load under traction, F/F(μ=0)1
Method & references
- Hertzian line-contact rollers with combined rolling and traction (tangential) load — max subsurface shear stress factor interpolated from a lookup table.
- Distinct from t4_1.htm (traction-roller-point-contact): different lookup table, and dF1 uses the square (line-contact pressure ~ F^(1/2)) rather than the cube (point-contact pressure ~ F^(1/3)) used for point contact.
The computation is a literal port of the original client-side JavaScript from /calculators/t4_2.htm. Results are verified equal to the original by an automated golden-master test. No formula has been re-derived or “improved”.