Page 238 - Industrial Power Engineering and Applications Handbook

Transmission of load and suitability of bearings 8/217
List of formulae used Radial forces on bearings

Selection of flat belts (8.3)
L
w=p.- SF (8.1 )
Correction for arc of contact K = belt factor
D = diameter of pulley (m)
P = the load to be transmitted (kW) W = Weight of complete rotor and driven masses on the
W = maxiinum load transmitting capacity of the belt motor shaft.
SF = service factor
Load-carrying capacity and life of bearings
To determine the pitch length of V-belts

Lh = normal life of bearing in working hours
L = belt pitch length (mni) C = basic dynamic load rating (kg or N)
C = centre distance between the two pulleys (mm) P = equivalent dynamic bearing load (kg or N)
I) = pitch diameter ot the larger pulley (mm) p = exponent of the life equation
il = pitch diameter of the smaller (fa5ter) pulley (mm) N, = speed of the machine (r.p.m.)