In gearboxes, maintenance scheduling revolves around ensuring lubrication quality and levels are maintained.
For Bonfiglioli’s A series of helical-bevel gearboxes, the oil type and running temperature both play a significant part in determining oil change intervals.
The table below details the oil change intervals in hours for Bonfiglioli A series gearboxes, with those variables considered.
| Oil change interval (h) | ||
| Oil Temp © | Mineral | Synthetic |
| <65 | 8000 | 25000 |
| 65-80 | 4000 | 15000 |
| 80-95 | 2000 | 12500 |
As you can see, the extended life of synthetic oil can reduce total maintenance costs, so must always be considered as part of any maintenance schedule regime. As usual with all oils, do not mix mineral and synthetic!
Many plants run condition monitoring systems, keeping an eye on bearing vibration and heat rise. Condition monitoring is one of the better ways to catch a gearbox failure before it happens, although it can be cost prohibitive.
Smaller wormboxes have got to the point where they are ‘lubricated for life’, in that they shouldn’t require relubrication before their effective working life comes to an end. This does not mean that units should not be checked as part of a routine maintenance schedule.
