What are common faults in three-roller mills?

1. Mechanical System Failure
Abnormal Roller Vibration
Cause: Uneven roller gap (error > 0.02mm), bearing wear, or foreign matter stuck in the rollers
Action: Calibrate parallelism, remove foreign matter, and replace bearings (e.g., NU236EM1C3 model).
Bearing Overheat (> 60°C)
Cause: Insufficient lubrication or insufficient cooling water flow
Action: Add high-temperature grease (e.g., lithium-based grease) and adjust the cooling water valve opening.
Abnormal Gearbox Noise
Cause: Planetary gear cracking or bearing spalling
Action: Shut down, disassemble, and replace damaged parts (e.g., second-stage planetary gears).
2. Process Control Failure Faults
Excessive material fineness
Cause: Excessive roller gap (>0.3mm) or worn scraper blade (blade >1mm)
Remedy: Adjust the gap and replace the scraper
Material leakage
Cause: Failed baffle seal or roller corrosion
Remedy: Replace the fluororubber seal; repair by overlay welding if corrosion is severe
Current fluctuation (>10% of rated value)
Cause: Excessive material viscosity or roller overload
Remedy: Dilute the material or reduce the feed rate
3. Hydraulic system failure
Insufficient roller pressure
Cause: Hydraulic oil contamination or cylinder seal failure
Remedy: Replace the hydraulic oil (ISO VG46) and inspect the seals
Hydraulic system vibration
Cause: Iron chips mixed in or oil line blockage
Remedy: Clean the oil line and install a magnetic filter