Practical use of autocorrelation and circular waveform
A coupling problem was identified and corrected in a conveyor belt at Vale’s Cauê Plant, in Itabira-MG, through continuous monitoring of the condition with triaxial vibration sensors from Dynamox. In the following video you can also see the image of the coupling, which shows damage to the elastic element and screws.
A conveyor belt is a critical asset for the mining production process and can travel long distances, which is why the vibration sensor is so relevant for monitoring the asset. The coupling, in turn, is responsible for the connection between the motor and the gearbox, and may present, in some cases, wear and misalignment.
The case was recorded on the Dynamox platform, where the sensor installed in the engine on the coupled side begins to show instability from September 2022, with vibration levels evolving and reaching an even more critical level in the month of October.
Tools assist in the identification of faults
Get to know some of the tools available in the Dynamox platform to identify the root cause of the evolution of this fault in detail in the video at the end of this text.
Among them, there is the cascade spectrum that allows the view of several spectrums in 3D form, bringing greater evidence to the identified evolution, characterizing the loss of coupling rigidity, elastic element wear and misalignment between the components.
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In addition to spectral cascade, another tool available and used to identify the fault at this point was autocorrelation. Combined with the circular view below, one can see the abnormality in the input coupling, characterized by the lateral displacement of the cycle.
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More information on the autocorrelation analysis is presented in the video.
With the help of the graphs used for the vibration analysis, the spot to be analyzed was highlighted and the intervention programmed for the replacement.
After the intervention, the levels of the graphs decreased considerably, demonstrating the efficiency of the collection tool and the work of Vale’s maintenance team. However, in the graph, even with the levels showing a decrease in amplitude, it is possible to verify in the third harmonic that a residual misalignment remained, which does not directly affect the equipment, but that in a scheduled maintenance it is possible to correct.
Check out the video with our operations manager, Caroline Menegat and Dynamox vibration analysis specialist, Joel Nunes.
Want to learn more about how asset condition monitoring can extend the life and optimize costs of your industry? Learn how to do industrial conveyor belt monitoring with vibration sensors and Dynamox tools by downloading this e-book.