Why it matters:
Some extruder gearboxes are planetary gearboxes. This type of gearbox is driven by one motor: turning the sun gear through several stages of gear reduction. For monitoring and diagnostics, this gearbox requires special handling.
The best approach
Be sure your monitoring system accounts for two critical factors. First, the analysis frequency for many components in a planetary gearbox is a function of motor speed. The monitoring system must be aware of the special formula required capable to compute the inherent fault frequencies of every machine element within the planetary gearbox which is a complex function of the input speed.
Second, the diagnostic system must provide a comprehensive and reliable analysis of the influence of design, production technology, operation and change of condition factors on vibration signals.