A newly installed pump was showing elevated vibration levels on the motor non-drive end (NDE). The maintenance team performed a standard alignment check using a dial indicator and declared it "within tolerance."
A review of vibration analysis and its applications - ScienceDirect
The case studies reviewed generally employ the following analysis techniques:
If you are a reliability engineer tasked with creating a training document or building a corporate memory, follow this template: Practical Case Studies On Vibration Analysis Pdf
Using the publicly available Case Western Reserve University (CWRU) bearing dataset—a benchmark standard in vibration analysis research—this study applied multiple signal processing techniques. Faults with defect sizes of 0.007, 0.014, and 0.021 inches were induced on inner races, outer races, and rolling elements of JEM SKF 6205-2RS bearings. The analysis employed time domain indicators, Fast Fourier Transform, spectrogram analysis, and envelope analysis using kurtogram techniques. For the specific bearing parameters (9 rolling elements, zero contact angle), theoretical fault frequencies were calculated: inner race at approximately 158 Hz, outer race at 104 Hz, and rolling element at 137 Hz.
Phase measurements taken across the bearing housing revealed a 180-degree phase shift from the top to the bottom of the bearing. This cross-channel behavior is a classic indicator of a bent shaft or severe angular misalignment, not unbalance. The Solution and Outcome
The GMF peak was surrounded by distinct sidebands spaced at the rotational speed of the input shaft. The presence of sidebands indicates modulation, which points directly to uneven gear tooth wear or tooth cracking. A newly installed pump was showing elevated vibration
October 26, 2023 Prepared For: Reliability Engineering Team / Maintenance Management Subject: Summary and Key Findings from Practical Vibration Analysis Case Studies
To effectively analyze case studies, engineers must first ground themselves in the primary indicators of machinery health. Vibration data is typically collected using accelerometers and analyzed via two primary domains:
1500 RPM (25 Hz operating frequency), belt-driven by a 45 kW induction motor. The analysis employed time domain indicators, Fast Fourier
"Do not trust velocity alone for bearing health. Include acceleration enveloping in your standard route. A PDF case study should always include the bearing calculation formula used."
This report reviews practical case studies regarding machinery health monitoring through vibration analysis. The primary objective is to highlight how vibration signature analysis is utilized to detect mechanical faults—such as imbalance, misalignment, bearing defects, and resonance—before they result in catastrophic failure.
Key takeaway:
Researchers conducted experimental testing on an asymmetric Stockbridge damper installed on the hangers of a long-span suspension bridge in northern Norway. Testing was performed on the complete damper as well as on its separated top and bottom masses to assess performance across various vibration frequencies and amplitudes.