Boiler Air Draft Fan Unbalance and Structural Weakness Problem
High vibration and noise levels at the motor were caused by an unbalanced fan impeller and a cracked structure. Cleaning the fan and welding the cracks reduced vibration and noise, but the structure should be reinforced vertically.
Equipment:
Boiler Air Draft Fan.
Problem: High Vibration and Noise Levels at Motor.
Vibration Readings:
1- High 1X values at Motor Vertical (DS & NDS) & Much more than in Horizontal side.
2- Harmonics & Subharmonics
Analysis:
1- The fan impeller is unbalanced due to contaminations.
2- Structure Weakness
Findings:
1- The fan was heavily contaminated with dust.
2- The structure was cracked at multiple locations
Solution:
1- The fan was cleaned using water jet.
2- The cracks were fixed by welding.
Results:
The vibration and noise levels were significantly damped.
Recommendation:
The structure need to be more stiffed in the vertical direction.
Additional Images
