During the operation of OK mill (vertical mill), due to direct contact with materials and high pressure, high temperature and wear, some accessories wear out quickly and are major wearing parts. The following are its core wearing parts and a brief description:
1. Grinding roller and grinding disc lining (wear-resistant lining)
Wear cause: direct rolling of materials, high pressure and grinding friction.
Features: The surface is covered with high-hardness wear-resistant materials (such as cemented carbide or surfacing layer).
Grinding roller sleeves and grinding disc linings need to be checked regularly and replaced or repaired when they are severely worn.
Replacement cycle: usually 6,000~15,000 hours, depending on the hardness of the material (such as clinker, slag, etc.).
2. Separator blades (dynamic powder selector rotor blades)
Wear cause: impacted by particles during high-speed rotation, the edges are easily worn.
Features: The blade material needs to be wear-resistant (such as high-chromium cast iron or ceramic coating).
Wear affects the powder selection efficiency and needs to be repaired or replaced regularly.
3. Sealing device (roller seal, housing seal)
Wear cause: Dust intrusion causes wear of seal rings, graphite rings or rubber parts.
High temperature environment accelerates aging.
Features: Failure of seals will lead to powder and oil leakage, and need to be replaced regularly.
4. Hydraulic system components
Vulnerable parts: hydraulic cylinder seals, high-pressure oil pipes.
Wear cause: Frequent pressurization causes seal fatigue.
Oil pipes rupture due to vibration or friction.
5. Lubrication system pipelines and filters
Vulnerable parts: lubricating oil pipes, filter elements.
Wear cause: Long-term oil scouring, particle contamination or vibration leads to blockage or leakage.
6. Water spray system nozzle
Wear cause: High-pressure water flow scours materials or dust, causing the nozzle aperture to expand or clog.
Features: Regular cleaning or replacement is required to keep the water spray volume stable.
7. Feeding device (air lock valve blade)
Wear cause: Material particles scour the air lock valve blade.
Features: Blade wear will cause air leakage, affecting the pressure balance in the mill.
8. Bearings (roller bearings, reducer bearings)
Wear causes: Heavy load, high temperature or poor lubrication lead to bearing fatigue or jamming.
Features: Temperature and vibration need to be monitored regularly and replaced in time.
9. Wear-resistant surfacing layer (roller/disc surface repair layer)
Wear causes: After long-term rolling of materials, the surfacing layer gradually peels off.
Features: It needs to be repaired by surfacing rather than replaced as a whole, which can extend the life of the components.
Other wearing parts
Transmission parts: such as coupling elastic blocks.
Air duct lining: Abraded and worn by particles carried by airflow.
Inspection door seal strip: Aging caused by high temperature and dust.
Summary
OK mill's wearing parts are mainly concentrated in parts that directly contact materials, high pressure or high-speed movement. The key to maintenance is:
1. Regularly check the amount of wear (such as liner thickness, sealing status).
2. Optimize operating parameters (such as pressure, temperature) to reduce losses.
3. Select highly wear-resistant materials or surface treatment technology.
4. Keep the lubrication and cooling systems running efficiently.
The actual replacement cycle needs to be comprehensively evaluated based on material properties (hardness, humidity), equipment operating load and maintenance level.
