· Life correction: microscopic defects in ceramics cause scatter; empirical factor 0.7–0.9 of calculated life (aerospace grade = 1.0).

· Speed correction: lab calculation should be increased 10-15% as safety margin, then fine‑tuned by measuring vibration.

· Lubrication experience: minimum λ for grease lubrication should be lowered to 1.0 (steel requires 1.5); observe running‑in temperature rise.