During the operation of a sawdust pellet mill, issues such as unstable current may arise. What causes this, and how does it affect pellet production? The ring die and pressure rollers of the mill rotate at a constant speed, meaning the operating state remains essentially uniform at any given moment; provided the feed rate remains constant, energy consumption—and consequently the motor current—should also remain relatively stable.
When adjusting the feed rate, if the material thickness in the feeding zone is less than the starting point of the compression zone, it directly affects the effective working length of the compression and extrusion zones, causing fluctuations in current and hourly output. Conversely, if the material layer thickness in the feeding zone exceeds the starting point of the compression zone, the only result is an increase in the layer thickness within the feeding zone itself; it does not affect hourly output or energy consumption, nor does it cause further fluctuations in current or output.
This is because, once the material layer thickness in the feeding zone exceeds the compression zone's starting point, the effective compression and extrusion zones remain constant. The excess material lies in a region where the nip angle exceeds the critical friction angle, meaning the material is not compressed. As the feed rate increases, the balance between input and output is disrupted (input exceeds output), causing the material layer in the feeding zone to accumulate and thicken until it fills all voids and blocks the inlet, preventing the mill from operating normally. At this point, the current increases.
Sawdust pellet mills are currently used by many enterprises, delivering significant benefits; however, improper use can lead to low output. What should be done if output is low? Here are a few suggestions:
1. Grind new dies. Due to current domestic manufacturing standards, the smoothness of the holes in new dies often falls short of the ideal level. The grinding process is simple: run the machine a few times using a mixture of engine oil, sand, and sawdust. For the detailed procedure, please consult the manufacturer or contact our customer service team.
2. Maintain the machine properly and replace dies in a timely manner. Over time, wear and tear on the dies and pressure rollers is inevitable. If the drop in output is caused by this issue, simply replacing the die with a new one will resolve it.
3. Adjust the moisture content of the raw materials. The wood pellet machine requires raw materials (such as sawdust) to have a moisture content of approximately 13%. Levels that are too high or too low will result in reduced output.
4. Properly adjust the pellet machine's parameters, such as the gap between the pressure rollers and the die. Different materials require different gap settings; low output may be due to an incorrect gap setting. Please have the manufacturer adjust this for you.
If the issue persists, please contact TONY technical staff for a detailed explanation.