Faults and Solutions Frequently Encountered in Twin Screw Extruders

When the twin screw extruder is used for a long time, some common faults will occur, so here are some knowledge about common faults, and then you can repair it by yourself.


1. The head pressure is unstable


Cause: The main motor speed is uneven. Or the speed of the feeding motor is uneven and the feeding amount fluctuates.


Solution: Check the main motor control system and bearings. Check the feeding system motor and control system.


2. The main motor cannot start


Cause: There is an error in the driving procedure. Or there is a problem with the main motor thread, whether the fuse is burned.


Treatment method: Check the procedure and restart in the correct driving sequence. Check the main motor circuit. Check whether the lubricating oil pump is started, and check the status of the interlocking device related to the main motor. If the inverter has not discharged the induction current, turn off the main power supply and wait for 5 minutes before starting. Check whether the emergency button is reset.


3. The host current is unstable


Causes: uneven feeding, damaged or poor lubrication of the main motor bearings, a certain section of heater failure, no heating, wrong extruder screw adjustment pad, or wrong phase, component interference.


Treatment method: check the feeder and troubleshoot. Check the main motor and replace the bearings if necessary. Check whether the heaters are working properly, and replace the heaters if necessary. Check the adjustment pad and pull out the screw to check if there is any interference in the screw.


4. The lubricating oil pressure is low


Cause: The pressure setting value of the pressure regulating valve of the lubricating oil system is too low. The oil pump is malfunctioning or the suction pipe is blocked.


Treatment method: check and adjust the pressure regulating valve of the lubricating oil system. Check the oil pump and oil suction pipe.


5. the main motor bearing temperature rise is too high


Cause: poor bearing lubrication. The bearing is severely worn.


Treatment method: check and add lubricant. Check the motor bearings and replace if necessary.


6. The main motor makes an abnormal sound


Cause: The main motor bearing is damaged. A certain SCR in the SCR rectifier circuit of the main motor is damaged.


Solution: Replace the main motor bearing. Check the SCR rectifier circuit and replace the SCR components if necessary.

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