In-Depth Analysis of Biomass Pellet Machine Core Components: Ring Die, Press Roller, Main Shaft, and Gearbox

The design, material, and operating conditions of these components directly impact pellet formation efficiency, energy consumption, and equipment stability.

Ring Die: The "Heart" of Pellet Forming

Function

· Extrudes the raw material into pellets through the die hole (usually 6-8mm diameter), determining pellet density and yield.

· The material and heat treatment process directly impact wear resistance.

Common Problems

❌ Die hole enlargement (>10% of the designed hole diameter results in loose pellets and increased fines).

❌ Surface cracking (due to uneven heat treatment or hard impurities in the raw material).

Maintenance Tips

✅ Regular Inspection: Before each shift, inspect the die hole for deformation, damage, etc.

✅ Scientific Run-in: New ring dies should be run at low speed for two hours using a feedstock containing 30% sand to polish the die hole.

Press Roller: Key to Pressure Transmission

Function

· Works with the ring die to extrude the raw material and form it.

· The thickness of the press roller skin (wear-resistant layer) determines the replacement cycle (wear > 3mm requires replacement).

Common Problems

❌ Bearing lock (insufficient lubrication or overtightening).

❌ Press roller skin peeling (raw material contains metal impurities or heat treatment defects).

Maintenance Points

✅ Lubrication Standard: Upon startup, turn on the automatic lubrication pump and add high-temperature grease (temperature resistance > 150°C). Check the oil line for unobstructed flow.

✅ Clearance Adjustment: Maintain a clearance of 0.1-0.3mm between the press roller and the ring die (calibrated with a feeler gauge).

Spindle: The Hub of Power Transmission

Function

· Bears the rotating torque of the ring die.

Common Problems

❌ Journal wear (seal failure allows dust to enter the bearing seat).

❌ Fatigue fracture (long-term overload operation). Maintenance Key Points

✅ Vibration Monitoring: Install a vibration sensor. Shut down the machine for inspection if the amplitude exceeds 0.5mm.

✅ Seal Upgrade: Use labyrinth and lip seals for dual protection.

Gearbox: The Core of Power Conversion

Function

· Reduces the motor's high speed to the ring die's operating speed.

Common Problems

❌ Gear tooth breakage (instantaneous overload or poor lubrication).

❌ Oil temperature too high.

Maintenance Key Points

✅ Oil Selection: Heavy-duty gear oil, replaced every 1000 hours.

✅ Temperature Control: Install an oil cooler (essential for high-temperature environments).

Optimization Suggestions

1. Preventive Maintenance: Establish a component replacement file and perform mandatory maintenance based on operating hours.

2. Accessory Upgrade: Prefer tungsten carbide ring dies and SKF bearings for better overall efficiency.

3. Intelligent Monitoring: Install temperature and vibration sensors for fault warnings.

Conclusion

Efficient operation of a biomass pellet machine depends on high-quality components and effective maintenance! Users need to have a deep understanding of the characteristics of core components in order to achieve cost reduction and efficiency improvement.