What is the purpose of vibration analysis in maintenance?

• A. To monitor overall energy usage.
• B. To predict weather.
• C. To measure soil moisture in the facility.
• D. To identify bearing wear, imbalance, misalignment, and looseness before failure.

Answer: (D)

Vibration analysis is used to detect signs of mechanical faults in rotating equipment by listening to how parts vibrate during normal operation. By capturing vibration with sensors and analyzing the signal in both time and frequency domains, technicians can spot patterns that point to specific issues. For example, imbalance tends to create vibrations at the machine’s running speed, misalignment shows up at twice the running speed and related harmonics, bearing wear appears at bearing fault frequencies, and looseness causes high‑amplitude, broad-band signals. Tracking these indicators over time lets maintenance intervene before a failure occurs, reducing downtime and preventing damage.

This isn't about monitoring energy usage, predicting weather, or measuring soil moisture, so those options don’t fit the purpose of vibration analysis.