ABNORMAL VIBRATION IN AN HFO PURIFIER - INVESTIGATION AND RECTIFICATION
Since no reduction in vibration was noticed even after desludging the purifier a couple of times, the vibration is not due to accumulated sludge in the bowl. The areas to investigate:
- Bowl/ rotor balance: Check the bowl and the bowl components (disc stack, top disc, bowl hood) for balance. An out-of-balance bowl (from a damaged/ missing disc, an unevenly loaded bowl, or a bent bowl) causes vibration. Check the bowl is correctly assembled and the disc stack is even; check for a bent/ damaged bowl spindle.
- Bowl spindle/ shaft: Check the vertical shaft (bowl spindle) for bending, wear, and correct fit in the bearings. A bent or worn spindle causes vibration.
- Bearings: Check the bowl spindle bearings (the thrust/ radial bearings) for wear, pitting, damage and correct clearance. Worn/ damaged bearings cause vibration. Check the bearing lubrication (oil level, condition, pressure).
- Bowl drive/ coupling: Check the drive coupling (the friction/ centrifugal coupling, or the gear drive) for wear, damage and correct engagement. A worn/ slipping coupling causes vibration.
- Bowl locking/ assembly: Check the bowl is correctly locked/ assembled (the bowl hood, locking ring, and the bowl is correctly seated on the spindle). An incorrectly assembled/ loose bowl causes vibration.
- Motor/ drive: Check the drive motor and the motor bearings for wear/ damage; check the motor is correctly aligned with the purifier.
- Foundation/ mounting: Check the purifier's foundation, the anti-vibration mounts/ springs, and the securing bolts for damage, wear or looseness. A loose/ damaged foundation or mount causes vibration.
- Bowl internals: Check the bowl internals (discs, distributor, paring disc) for damage, blockage, or an unevenly loaded bowl (e.g. a broken disc).
- Balance/ run-out: Check the bowl run-out (dial indicator) and the overall balance; re-balance the bowl if necessary.
Rectification:
- Correct the identified fault: re-balance/ re-assemble the bowl, renew the worn bearings/ spindle, repair the coupling, tighten/ repair the foundation/ mounts, or renew the damaged parts.
- After rectification, run the purifier and check the vibration is within limits; confirm normal operation (correct separation, no abnormal noise/ vibration).