Overhung (Fr) & Thrust (Fa) Loads
The permissible overhung loads (Fr) and thrust loads (Fa) for the individual gear boxes must also be taken into consideration when selecting a gear box.
If overhung loads (Fr) are encountered together with thrust loads (Fa), the overhung load (Fr) is reduced by the value of the thrust load (Fa).
Formula to calculate Overhung Load (OHL)
Transmission Elements | Notes | Factor fz |
---|---|---|
Spur or Helical Gears | 17 teeth or more | 1.00 |
less than 17 teeth | 1.15 | |
Chain & Sprockets | 20 teeth or more | 1.00 |
less than 20 teeth | 1.30 | |
less than 13 teeth | 1.40 | |
Timing Belt & Pulley | – | 1.30 |
V-Belt & Pulley | dependent on pre-tension | 1.50~2.00 |
Flat Belt & Pulley with tension roller | dependent on pre-tension | 2.00~2.50 |
Flat Belt & Pulley without tension roller | dependent on pre-tension | 2.30~3.00 |