What are the common faults of high pressure grinding rolls and how to solve them

The high pressure grinding rolls is composed of two rollers, one of which is fixed and the other can slide horizontally. The material is continuously fed from the top and passes through the gap between the rollers. The movable roller is pressurized by hydraulic pressure, the material is crushed by pressure, and is pressed into cakes and falls out of the machine.

High pressure grinding rolls may encounter a variety of common faults during operation. These faults and their solutions can be summarized as follows:

1. Abnormal vibration

Fault causes:

Uneven material size: Uneven material size will cause the extrusion force of the equipment to be unbalanced, causing vibration.

Severe wear of the scraper: The scraper cannot effectively shovel the material after wear, causing the roller to squeeze the material sometimes and sometimes not, causing vibration.

Too hard material: Too hard material may cause deformation and wear of the grinding roller and grinding ring, thereby aggravating vibration.

Fan problem: The fan blades of the high-pressure suspended shaft grinding fan accumulate too much powder or wear, causing unbalanced rotation of the fan blades.

Loose anchor bolts: After the equipment has been used for a period of time, the anchor bolts may loosen due to vibration or installation reasons.

Solution:

Adjust the particle size of the material and try to make it uniform.

Regularly check and replace worn scrapers.

Avoid processing of too hard materials, regularly check and replace grinding rollers and grinding rings, and remove metal debris from the material.

Remove the accumulated powder on the fan blades in time, and replace them in time if they are worn.

Pay attention to the tightness of the anchor bolts during daily maintenance. Tighten them in time if they are loose.

2. Powder discharge problem

Cause of failure:

Wear of shovel blade: Wear of shovel blade leads to reduced powder discharge.

Powder lock is not adjusted properly: The seal of powder lock is not tight, resulting in powder back-sucking.

Solution:

Check and replace worn shovel blades regularly.

Stop the machine to check and adjust the seal of powder lock, and seal the air leak.

3. Finished product particle size problem

Cause of failure:

Incorrect adjustment of fan air volume.

Analyzer blades are worn.

Solution:

Adjust the air volume according to the coarseness of the discharged material. If it is too coarse, adjust the air volume to a small amount, and if it is too fine, adjust the air volume to a large amount.

Replace the worn analyzer blades in time.

4. Motor problem

Cause of failure:

Excessive feeding leads to blockage of the air duct by powder, poor exhaust, and heating of the circulating airflow.

Solution:

Stop the machine to clean the accumulated powder in the air duct, reduce the feed amount, and open the air duct valve at the same time to control the temperature of the incoming material within an acceptable range.

5. Other common faults

Lubrication system problems: If there is no grease overflow from the labyrinth seal of the bearing seat, it may be due to lack of oil, pipeline failure or damage to the grease pump. It is necessary to check and replenish the grease, repair the pipeline or replace the grease pump.
Irregular movement of the moving roller: It may be that the nitrogen accumulator pressure is insufficient or damaged. It is necessary to check and adjust the nitrogen accumulator pressure or replace the damaged parts.

High hydraulic oil temperature: It may be that the system has serious internal leakage or the pump has been running for too long. The hydraulic system needs to be checked and repaired.

Roll gap problem: If the roller gap is too large, it may be that the roller surface is severely worn, there is no pressure, or there is material accumulation between the rollers; if the roller gap is too small, it may be that there is a problem with the size of the gap block or the position of the displacement sensor is set incorrectly. It is necessary to adjust or replace parts according to the specific situation.

Roller stuck or not turning: It may be that there is foreign matter between the rollers, too much material is stored between the rollers at startup, motor failure or reducer failure. It is necessary to clean up foreign matter, reduce the amount of material stored at startup, and check and repair the motor or reducer.

In summary, the common faults of high pressure grinding rolls involve many aspects, which need to be checked and solved according to the specific situation. In daily use, the operation should be strictly carried out in accordance with the operating procedures, and the maintenance of the equipment should be strengthened to reduce the occurrence of faults.