What causes the fan bearing to vibrate during boiler operation?

Why Fan Bearings Vibrate in ZOZEN Coal-Fired Boilers
Fan bearings (in FD/ID fans, primary air fans, etc.) are critical for stable combustion and heat transfer. Vibration indicates abnormal forces or wear, requiring prompt diagnosis to avoid failure. Below are key causes and ZOZEN-specific solutions:

Primary Causes of Fan Bearing Vibration
Imbalance

Cause: Coal dust/debris buildup on fan blades, uneven wear, or manufacturing tolerance deviations.

ZOZEN Solution: Dynamically balanced rotors at factory + anti-fouling blade coatings.

Bearing Wear/Damage

Cause: Lubrication failure (over/under-greasing), contaminants (ash, moisture), or fatigue from extended operation.

ZOZEN Engineering: Sealed bearing housings + automated lubrication systems on high-end models.

Misalignment

Cause: Improper coupling alignment between motor/fan shafts during installation or thermal expansion shifts.

ZOZEN Protocol: Laser alignment during commissioning + thermal growth compensation design.

Resonance & Structural Issues

Cause: Natural frequency matching between fan speed and support structure/ductwork.

ZOZEN Design: Stiffened bases, vibration isolators, and FEA-optimized structural dynamics.

Poor Lubrication

Cause: Incorrect grease type, degraded oil, or blocked lubrication channels.

ZOZEN Support: OEM-specified lubrication schedules + IoT sensors for real-time monitoring (optional).

Thermal Stress

Cause: Uneven heating/cooling warps shafts or housings.

ZOZEN Feature: Heat shields on bearings near high-temp zones (e.g., ID fans).

Electrical Issues (Motor Side)

Cause: Motor rotor imbalance, soft foot, or electromagnetic forces.

ZOZEN Integration: Certified motor-fan assemblies tested for vibrational harmony.