Over the past 20 years, we’ve specialized in the maintenance, rapid repair, and comprehensive overhauls of horizontal screw centrifuges. Our primary repair services cover a wide range of models, including imported brands like Flewis, Alfa Laval, Anderitz, Beares, Vesfaria, and Ishikawashima, along with domestically produced options such as Ruiwei, Haishen, Shangli, Qingtian, and Lushui. We address the common maintenance challenges faced by many domestic users operating horizontal spiral centrifuges. To help everyone better understand and manage common centrifuge issues, I’ve compiled the following insights:
### 1. Oil Pressure Failure Issues
Oil pressure problems in centrifuges often manifest as no oil pressure, insufficient pressure, or excessively high pressure. Here’s how to handle these scenarios:
- **No Oil Pressure**: Inspect the oil filter for blockages, verify that the pressure gauge is functional, ensure all oil lines and connections are secure without leaks or cracks, and confirm that the oil lines are unobstructed.
- **Low Oil Pressure**: Normally, the outlet pressure for coal preparation plant centrifuges should be around 3.0–3.5 bar. If the pressure is too low, check the oil line from the pump to the tank for obstructions, inspect the oil circuit for leaks, examine the coupling between the motor and oil pump shaft for damage (replace if necessary), and verify the condition of the oil pump.
- **High Oil Pressure**: If the oil pressure is too high, review the equipment manual to ensure the correct type of lubricant is being used. Also, check the pipelines for blockages—use compressed air to clear any debris if needed.
### 2. Excessive Vibration During Operation
Vibrations exceeding acceptable levels during centrifuge operation are usually due to improper installation, a blocked or deformed screen basket, obstructed coal channels, or loose bolts. Solutions include:
- Inspect the screen basket for blockages, wear, or deformation.
- Check the condition of the exciter springs to see if they’re aged.
- Look for fine coal accumulation on one side of the screen basket.
- Ensure the wedge-shaped screen basket isn’t damaged, deformed, or unbalanced.
- Verify that the ground anchor bolts aren’t rusted or loose.
- Inspect the bearings for damage; if damaged, replace them.
- When replacing a new vibrating motor, ensure it matches the load requirements and is synchronized with the other motor.
### 3. Abnormal Noise Failures
Abnormal noises are typically caused by a narrow gap between the screen basket and scraper, foreign objects inside the equipment, or damaged bearings. Solutions include:
- Check the gap between the screen basket and scraper.
- Inspect the oil circuit for proper functioning.
- Ensure no foreign objects have entered the machine.
- Check for belt damage or detachment.
- Inspect the condition of the bearings.
### 4. Motor Failure Issues
Motor-related problems can disrupt the centrifuge’s operation. Common issues and solutions include:
- **Failure to Start or Shut Down**: Verify that the power supply voltage is stable and the starter is functioning correctly. Ensure the motor is properly grounded, with no phase breaks or short circuits. Confirm that the motor isn’t overloaded either mechanically or electrically.
- **Overcurrent or Overheating**: Check that the motor mounting bolts are secure and that the end cover isn’t damaged. Investigate whether the bearing is partially seized or excessively greased. Reduce the feeding volume if it’s too high. Clean the discharge area if there’s material buildup at the bottom.
### 5. Feeding and Discharge Failures
Feeding and discharge issues often result from screen basket wear, excessive coal volume, or high moisture content in the coal-water mix. Solutions include:
- Check for screen basket abrasion or leakage. Replace the screen basket immediately if wear is detected.
- If the coal feed is poorly processed, reduce the amount of coal sludge, and strengthen the control of coal input.
- If the moisture content in the feed is too high, adjust the input mixture’s moisture and fine coal ratio. Inspect the screen basket for blockages and check the gap between the scraper and screen basket. Also, inspect the chute for wear.
These insights represent innovative approaches to addressing common centrifuge maintenance problems. By understanding these solutions, you can significantly reduce the likelihood of operational disruptions and improve the longevity of your centrifuges.
ZHITONG PIPE VALVE TECHNOLOGY CO.,LTD , https://www.ztongvalve.com