Journal Bearing Calculator

Calculate minimum film thickness, friction, power loss, and temperature rise for hydrodynamic journal bearings.

Load on the bearing.
N
Shaft diameter at the bearing.
mm
Axial length of the bearing.
mm
Radial clearance between shaft and bearing. Typical: D/1000.
mm
Shaft rotational speed.
rpm
Dynamic viscosity. ISO VG 32: 0.03, VG 68: 0.06 Pa·s.
Pa·s

Results

Sommerfeld Number-
Unit Load-MPa
Min Film Thickness (est)-μm
Power Loss-W
Temperature Rise-°C
References: Hamrock — Bearing Tribology; Raimondi-Boyd Charts