Field case · Condition monitoring
Cement mill gearbox: 8.5 Hz sidebands pointed to a worn gear on the intermediate shaft, and the teardown five months later proved it
Shock pulse, envelope and velocity spectra all showed sidebands at the speed of the intermediate shaft. The gearbox was opened in December: worn gear teeth, bearing wear and cement particles in the oil.
What the case covers
- The application
- Reading the gear train
- What the spectra showed
- Why that points at a gear and not a bearing
- Teardown in December
- What was found
- What to apply
Takeaway. Sidebands tell you which shaft carries the damaged gear. When the same spacing shows in several views and the oil is full of cement, plan the opening.
Read the full case, with the data and the numbers