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Detection Method for Bolt Loosening Based on Summation Coefficient of Absolute Spectrum Ratio
Haoyang Guo1, Jianfeng Zhong1, Bin Feng1
1Fujian Provincial Key Laboratory of Terahertz Functional Devices and Intelligent Sensing, School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350108, China.
Sensors (Basel, Switzerland)
|January 11, 2025
Summary
This study introduces a novel bolt loosening detection method using the Summation Coefficient of Absolute Spectrum Ratio (SCASR). The technique effectively identifies and quantifies bolt looseness in mechanical connections, even in early stages.
Area of Science:
- Mechanical Engineering
- Vibration Analysis
- Condition Monitoring
Background:
- Bolt loosening is a critical failure mode in mechanical connections, compromising structural integrity.
- Existing detection methods may lack sensitivity, especially for early-stage loosening.
Purpose of the Study:
- To develop and validate a novel method for detecting and evaluating bolt loosening using vibration and speed signals.
- To establish a quantitative relationship between signal features and the degree of bolt looseness.
Main Methods:
- Utilizing Chirp Fourier Transform (CFT) to obtain spectrum curves of healthy and loosened bolt connections.
- Defining and calculating the Summation Coefficient of Absolute Spectrum Ratio (SCASR) from spectrum ratios.
- Establishing a linear relationship between SCASR and resonance peak frequency shift for quantitative analysis.
Main Results:
- A linear correlation was found between SCASR and resonance peak frequency shift.
- The proposed method effectively detects bolt loosening, including early stages, using low-frequency, tri-axial data.
- Experimental validation confirmed the method's efficacy in identifying looseness severity.
Conclusions:
- The SCASR technique provides a reliable and sensitive approach for bolt loosening detection.
- The method offers a standardized index for evaluating bolt integrity and predicting potential failures.
Keywords:
Summation Coefficient of Absolute Spectrum Ratiochirp Fourier transformdetection index for bolt loosening degreeearly stage of bolt looseningreference spectrum curveMore Related Videos
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