Due to differences in processing techniques and temperatures, there are significant differences in operating precautions between hot rolling machines and cold rolling machines:
I. Operating Precautions for Hot Rolling Machines
Temperature Control
The oil furnace temperature must be strictly controlled above 80℃ before starting the rolling machine. When stopping, it should be reduced to below 80℃ before shutting down the motor to prevent the rollers from deforming due to heat. For plain carbon steel rolling, the heating temperature should be maintained at 1150-1200℃, and the temperature difference across the cross-section should be ≤ 40℃.
Roller Maintenance
The cooling water pressure for the rollers must be sufficient. Blocked water pipes should be promptly cleared; after stopping, the adhering substances on the rollers should be cleaned, and hard tools should not be used for cleaning. The pressure plates and screw bolts of the roller bearing seats need to be checked for tightness regularly.
Safety Protection
When operating, touching the heated rollers is strictly prohibited to prevent burns; the emergency stop device must be kept in normal condition, and it should not be touched randomly in non-emergency situations. When multiple people are collaborating, attention should be paid to the guiding operation to avoid personal injury.
II. Operating Precautions for Cold Rolling Machines
Pressure and Precision Control
Cold rolling requires higher pressure for rolling. Ensure that the parallelism of the rollers and the alignment with the axis are correct, and the gap of the finishing mill window should be ≤ 0.8mm to ensure dimensional accuracy. When rolling thin plates, start each cut separately to avoid cracking defects.
Lubrication and Cleaning
The gearbox should be cleaned quarterly. The lubricating oil should be regularly tested for cleanliness and viscosity, and key components such as bearings should be lubricated with high-viscosity lubricants at fixed points. The surface of the rollers should be kept smooth without oxide scales to avoid contact with hard objects.
Abnormal Handling
If irregular noises or abnormal loads are detected, stop the machine immediately for inspection to avoid roller contact and impact. The fly-cutting area should be cleared of debris to ensure the normal state of the guiding rollers.
III. General Precautions
For hot rolling machines, prevent the influence on surface quality due to high-temperature iron oxide scales; for cold rolling machines, avoid brittle fractures caused by poor plasticity.
Both require regular inspection of roller wear conditions and matching replacement of the entire machine to ensure continuous production.
