Equipment Type
Fan
Equipment Name
Intermediate Frequency Furnace Dust Removal Fan
Faults
Rotor Unbalance, Foundation Looseness
Early Detection of Intermediate Frequency Furnace Dust Removal Fan Foundation Looseness
How Wisper CMS Ensured Continuous Operation at an Aluminum Manufacturing Factory
Metallurgical
Introduction
This case study demonstrates the diagnosis of a foundation looseness or rotor unbalance fault in an intermediate frequency furnace dust removal fan at an electrolytic aluminum plant. In aluminum manufacturing, the continuous operation of dust removal fans is crucial for maintaining process stability and environmental compliance. This case demonstrates how an AI-powered condition monitoring solution detected an early-stage fault, enabling timely maintenance and validating the system’s diagnostic accuracy.
Equipment Overview
Combustion air fans, such as the Intermediate Frequency Furnace Dust Removal Fan, are typically motor-driven and connected to an impeller via a shaft. As the impeller rotates, a negative pressure (low-pressure zone) is created at the fan's inlet, drawing in smoke or air. The rotating impeller accelerates the gas, transferring dynamic energy to increase its speed and dynamic pressure. The accelerated gas is then discharged through the fan's emission pipeline into the atmosphere via a stack or other emission equipment. The fan's ability to regulate gas flow and emission pressure is essential for meeting diverse industrial needs.
The Challenge
The severe and continuous operational demands of the electrolytic aluminum industry require high reliability from critical equipment. Faults like foundation looseness, if left unaddressed, can rapidly escalate into severe vibration, bearing degradation, and costly unplanned shutdowns. Early and accurate detection is essential to justify intervention costs, prevent production losses, and maintain operational continuity.
Wisper Solution
Wisper CMS provided health status monitoring for the factory's intermediate frequency furnace dust removal fan. On January 26, 2025, shortly after the fan was commissioned into the Wisper CMS, the system detected a rapid decline in the diagnostic score for the Velocity RMS vibration indicator at the output end measurement point of the over-bridge bearing. The score quickly dropped from a healthy status to a Warning status. The system immediately generated a diagnostic report, advising the customer to monitor the equipment's condition.
Wisper CMS diagnostic report (Jan 26, 2025)
Timeline of Events
The outcome
Following the corrective action and equipment restart, the Velocity RMS diagnostic score for the over-bridge bearing output end measurement point returned to a healthy running state. The on-site maintenance results were fully consistent with the AI diagnostic report. This highlights the tangible value of AI-driven condition monitoring in accurately identifying faults and enabling proactive maintenance actions to reduce downtime risk.
understanding the root cause
Foundation looseness, which was the final confirmed fault, can arise from multiple factors:
Loose or broken anchor bolts or coupling bolts.
Structural looseness or insufficient strength in the equipment baseplate, base, or concrete foundation.
Deterioration or breakage of the grout.
Deformation of the frame or base.
