Structure of a cement roller press
A cement roller press is a main equipment in a cement grinding unit, which plays a crucial role in improving grinding efficiency and saving energy. It is widely used in the combined grinding systems with cement ball mills. The main structure is composed of two rollers of the same size rotating in opposite directions. One roller is fixed on the frame, and the other roller is movable. Four oil cylinders drive the roller to rotate in the frame guide rail to squeeze the material. The structure is relatively complex, the load is large, there are many systems and components, the working environment is harsh, and the parts are aging, so failures are inevitable during use.
Common failures and solutions
Abnormal noise
The main fault manifestation is sharp metallic friction or collision sounds during the operation of the cement roller press.
Possible reasons
- Bearing damage: Long-term wear can lead to bearing failure, which in turn causes abnormal noise.
- Loose fasteners: Loose bolts, screws, and other fixings can cause the machine to vibrate during operation.
- Material jam: If large pieces of material or other debris get stuck between the rollers, a knocking sound will occur.
Solutions
- Bearing replacement: Severely worn bearings should be regularly inspected and replaced to ensure proper machine operation.
- Fastener inspection: Ensure all fasteners, such as bolts and screws, are secure and tightened regularly to prevent loosening and vibration.
- Roller surface cleaning: Regularly clean the roller surface to prevent large pieces of material or other debris from becoming stuck between the rollers, which could cause clattering noise.
Unstable pressure
Unstable pressure is a common failure in the cement roller press.
Possible reasons
- Hydraulic system leaks: Seals of the pipe connecting parts leak.
- Pump and valve failures: The hydraulic pump and internal parts of the control valve are damaged.
- Clogged filters: The filter is clogged, and the liquid oil is blocked.
Solutions
- Thoroughly inspect the seals: Inspect all connections and immediately repair any leaks.
- Thoroughly inspect the pumps and valves: Perform a thorough inspection of the hydraulic pumps and control valves. If any damaged parts are found, replace them promptly.
- Regularly clean and replace the filters: To ensure unobstructed oil flow, clean or replace the filters regularly.
Too high a temperature
The high temperature of the cement roller press is mainly concentrated in the bearings. On the one hand, the heat is transferred to the bearing seat by the temperature of the clinker itself and the heat generated by the roller press rollers working on the clinker; on the other hand, the heat is generated by the rotational friction of the roller press bearings themselves and the heat generated by the reaction force of the roller press bearings to resist the rollers squeezing the clinker.
Possible reasons
- Heat dissipation issues: Cooling system failure, such as the fan being faulty or the cold water pipe being clogged.
- Lubrication conditions: Inadequate lubricating oil, or the quality is low.
- Load Management: Long-time overload operation.
Solutions
- Cooling duct cleaning: Regularly remove accumulated dust and debris from the cooling ducts to ensure smooth operation of the cooling system.
- Lubricant management: Add an appropriate amount of high-quality lubricant and replace it at prescribed time intervals to reduce wear on mechanical parts.
- Load scheduling: Rationally plan production plans to ensure that equipment will not be in an overloaded working state for a long time, thereby ensuring its safe and stable operation.
Uneven discharge particle size
Symptoms include significant differences in finished product particle size, which deviates significantly from the process settings.
Possible reasons
- Uneven roller wear: Excessive wear in localized areas of the roller surface causes variations in the roller gap.
- Unstable feed: An unstable feed rate, sometimes fast and sometimes slow, directly affects the quality of compaction.
- Adjustment error: Failure to achieve optimal roller spacing results in variations in the output particle size.
Solutions
- Regular inspection and maintenance: Roller wear should be carefully inspected regularly. If excessive wear is detected, the roller skins should be promptly turned or replaced to ensure uniformity in the roll gap.
- Feed speed control: During production, a stable feed speed should be maintained to avoid fluctuations in the feed rate, thereby ensuring consistent compaction quality.
- Precise roller gap adjustment: Finely adjust the gap between the rollers based on actual production needs to achieve a consistent output particle size and improve product quality.
Cement roller press daily maintenance tips
For the above common faults, it is recommended to pay attention to daily maintenance. Prevention is better than cure.
- Inspect the roller surface each month; if peeling is found, the repair welding should be carried out in time.
- Prepare an iron plate with different sizes, such as 5mm, 8mm, 10mm, 12mm, and 14mm, to adjust the gap between rollers.
- Check the cleanliness of the hydraulic oil daily. It is recommended to replace it after three months of operation, and extend the service life of the master cylinder.
- Check the tightness of the tightening sleeve bolts every month and adjust according to the torque requirements.
- After one month of operation, it is recommended to tighten the main frame bolts and universal joint bolts.
- Measure the oil delivery of the lubrication pump every quarter. Generally, the required amount of oil for bearing is more than 25 grams, and the amount of oil required at the sealing ring is more than 15 grams.
- After the operation, if the oil cylinder leaks oil, it is recommended to clean it and replace it diagonally.
- A connecting steel platform and a step ladder can be added between the two roller presses.
- Check the nitrogen pressure in the accumulators every month. One should be around 70 bar and the other around 120 bar.
