A plot of vibration amplitude against time, critical for detecting impacts, loose parts, and transient events.
Vibration data was collected from the fan bearings in the horizontal, vertical, and axial directions.
The presence of BPFI frequencies with running speed sidebands confirmed on the inner ring of the drive-end rolling-element bearing.
A high-speed centrifugal fan suddenly develops high vibrations, leading to severe structural shaking. Practical Case Studies On Vibration Analysis Pdf
: Speed trials on a vessel identified high axial and vertical vibrations at 7 Hz, which corresponded to the engine firing rate. Inspection revealed a slack chain driving the second moment balance shaft, which required tightening and weight adjustment. Common Diagnostic Patterns
A single reading is just a snapshot. Trending data over time is crucial for diagnosing machine health.
phase shift was recorded between the horizontal and vertical measurements on the same bearing housing. A plot of vibration amplitude against time, critical
Bacci, G., Øiseth, O., Petersen, Ø. W., et al. (2025). Experimental study of an asymmetric Stockbridge damper . In: Proceedings of the 9th European-African Conference in Wind Engineering.
The SH-75 SB Bridge over Wilson Creek in McKinney, Texas was observed to have excessive vibration and cracking on the concrete deck. While vibration is a serviceability issue recognised by the American Association of State Highway and Transportation Officials (AASHTO), the existing deflection limit was deemed inadequate by researchers as a countermeasure for vibration.
: A pump operating at 5100 RPM showed elevated vertical vibration at 1x RPM. Common Diagnostic Patterns A single reading is just
TIME DOMAIN SIGNAL FFT PROCESSING FREQUENCY SPECTRUM Amplitude Amplitude ^ /\ /\ ^ | | / \ / \ | | (Unbalance 1x) | / \/ \ | | +-------------------> Time +----------+-----------> Frequency 1x 2x
High-frequency acoustic emissions detectors flagged an anomaly on the drive-end bearing, though traditional velocity readings stayed within baseline parameters. Diagnostic Data and Spectrum Analysis
To ensure accurate diagnostics, data collection must follow strict technical parameters:
2× RPM dropped to 1.2 mm/s. Fan ran smoothly for 10+ months.