1、 Preparation before operation
1. Equipment inspection
Confirm that the power circuit, lubrication system, and cooling device are normal, check that the mold or nozzle is securely installed, and that the filter screen is not blocked.
Manually rotate the screw 3-5 times and check for any abnormal sounds or blockages.
Check that the safety devices (emergency stop button, protective cover) are functioning properly, wear heat-resistant gloves (above 200 ℃) and dust masks.
2. Material preparation
The raw materials need to be pre processed, with particle size not exceeding 3 millimeters and moisture content controlled within 5%. The residue in the hopper needs to be cleaned thoroughly.
2、 Start and Run
1. Preheating and no-load testing
Set the temperature (such as 180 ℃) and keep it warm for 45-60 minutes. Run at low speed for 5-10 minutes and observe that the motor current fluctuation does not exceed 10%.
Check if the heating system, vacuum device (vacuum degree ≥ -0.08MPa), and exhaust system are functioning properly.
2. Feed and parameter control
Slowly feed, adjust the screw speed to balance with the feeding speed, control the temperature error of the barrel within ± 5 ℃, and the temperature error of the mold within ± 3 ℃.
To avoid overload, the current load should not exceed 85% of the rated value. If blockage is found, stop feeding immediately and clean up after the current drops by 30%.
3、 Shutdown and maintenance
1. Shutdown process
Stop feeding 30 minutes in advance, gradually reduce the speed to the no-load state, turn off the heating system, and continue running until the barrel temperature is below 80 ℃.
Clean up the residual material of the nozzle, check the condition of the machine seal and bearings, and replace or add oil for maintenance if necessary.
2. Daily maintenance
Supplement lithium grease (NLGI2 grade) every week, and check the screw wear every month (maximum clearance 0.5mm).
Regularly clean the cooling water tank, vacuum buffer tank, and machine head residue.
4、 Safety precautions
Maintain a distance of ≥ 50 centimeters from the moving parts during operation, and prohibit adjusting the roller distance with load or forcibly braking.
If there is abnormal vibration (amplitude>0.15mm) or sudden malfunction, the machine should be stopped immediately, the power should be cut off, and maintenance should be carried out by hanging a tag.