Contacts retro flank (gear)
They are the result of insufficient backlash or just marks at equipment’s stop phases (unbalance and reverse rotation). We therefore recommend a control of operating clearances.
In the case of a projection on the extremity only, we recommend:
- For the gears, a control of pinion bearings
- For the gearboxes, control of bearing clearance
The best way to get usable information is either the temperature control in operation or applying a blue trace (active flank, retro flank) to confirm the load distribution.