Industrial Centrifuge Vibration Severity Checker

Per ISO 10816, up to 2.3 mm/s RMS is new-machine condition (zone A) and up to 4.5 mm/s is acceptable for unrestricted long-term operation (zone B). Between 4.5 and 7.1 mm/s the machine should be scheduled for corrective maintenance (zone C), and above 7.1 mm/s vibration is severe enough to cause damage (zone D).

Usually it is the critical-speed pass: flexible-mounted centrifuges deliberately run above their first critical, so they cross a resonance during every start and stop. A brief, repeatable spike at the same speed is normal; a spike that grows from week to week, or new vibration at full speed, is the real warning.

On the main bearing housings, with the machine at full process speed and typical load — as close to the bearing as possible, on stiff metal (never on covers or guards). Take horizontal, vertical and axial readings if you can; use the highest for the ISO grade and always re-measure at the same spot, load and speed.

The usual suspects are uneven cake/product distribution in the bowl, residual heel build-up, worn isolators, main bearing wear and gearbox (decanter) faults. A frequency spectrum tells them apart: imbalance shows at 1× running speed, misalignment at 2×, bearing defects at non-synchronous frequencies, and looseness as a raised noise floor with harmonics.

Velocity in mm/s RMS, 10–1,000 Hz. ISO 10816 zone tables are defined on broadband RMS velocity because it weights low- and high-frequency faults evenly for general machines. Acceleration (g) suits high-frequency bearing analysis and displacement (µm) suits low-speed machines, but neither maps onto these zone boundaries.