Plastic Extruder Failure Analysis

Plastic extruder is a common plastic machinery equipment. In the process of daily operation of the extruder, various faults will occur in the extruder, affecting the normal production of plastic machinery. Let's analyze the extruder fault.
Unstable main machine current
1. Production reasons:
⑴ Uneven feeding.
⑵ The main motor bearing is damaged or poorly lubricated.
⑶ A certain section of the heater fails and does not heat.
⑷ The screw adjustment pad is incorrect, or the phase is incorrect, and the components interfere.
2. Treatment method:
⑴ Check the feeder and troubleshoot.
⑵ Repair the main motor and replace the bearing if necessary.
⑶ Check whether each heater is working properly and replace the heater if necessary.
⑷ Check the adjustment pad and pull out the screw to check whether the screw has interference.
The main motor cannot start
1. Cause:
⑴ The start-up procedure is wrong.
⑵ There is a problem with the main motor thread, whether the fuse is burned.
⑶ The interlocking device related to the main motor is working
2. Treatment method:
⑴ Check the program and start again in the correct start-up sequence.
⑵ Check the main motor circuit.
⑶ Check whether the lubricating oil pump is started and the status of the interlocking device related to the main motor. If the oil pump is not turned on, the motor cannot be turned on.
⑷ The induction electricity of the inverter has not been discharged. Turn off the main power and wait for 5 minutes before starting.
⑸ Check whether the emergency button is reset.
The head of the machine is not discharging smoothly or blocked
1. Cause:
⑴ A certain section of the heater does not work, and the material is not plasticized well.
⑵ The operating temperature is set too low, or the molecular weight distribution of the plastic is wide and unstable.
⑶ There may be foreign matter that is not easy to melt.
2. Treatment method:
⑴ Check the heater and replace it if necessary.
⑵ Verify the set temperature of each section, and consult with the process engineer if necessary to increase the temperature setting value.
⑶ Clean and check the extrusion system and the head.
The main power starting current is too high
1. Cause:
⑴ Insufficient heating time and large torque.
⑵ A certain section of the heater does not work.
2. Treatment method:
⑴ Use handwheel when driving. If it is not easy, extend the heating time or check whether the heaters of each section are working normally.
The main motor makes an abnormal sound
1. Cause:
⑴ The main motor bearing is damaged.
⑵ A thyristor in the thyristor rectifier circuit of the main motor is damaged.
2. Treatment method:
⑴ Replace the main motor bearing.
⑵ Check the thyristor rectifier circuit and replace the thyristor element if necessary.