Failure Analysis Of Plastic Extruder Machine

Plastic extruder is a common plastic machinery. In the process of daily operation of the extruder, there are various failures in the extrusion machine, which affects the normal production of plastic machinery. Below we analyze the failure of the extruder.

Host current is unstable

1. Cause:

(1) Feeding is uneven.

(2) The main motor bearing is damaged or poorly lubricated.

(3) A certain heater fails and does not heat up.

(4) The screw adjustment pad is incorrect, or the phase is wrong, and the components interfere.

2. Processing Method:

(1) Check the feeder to troubleshoot.

(2) Repair the main motor and replace the bearing if necessary.

(3) Check that each heater is working properly and replace the heater if necessary.

(4) Check the adjustment pad and pull out the screw to check the screw for interference.

Main motor cannot start

1. Cause:

(1) The startup procedure is wrong.

(2) There is a problem with the main motor thread, and the fuse is burned.

(3) The interlocking device related to the main motor functions

2. Processing Method:

(1) Check the procedure and drive again in the correct driving order.

(2) Check the main motor circuit.

(3) Check if the lubricating oil pump is started and check the status of the interlocking device related to the main motor. The oil pump does not turn on and the motor cannot be turned on.

(4) After the inverter's induction power is not discharged, turn off the main power and wait for 5 minutes before starting.

(5) Check if the emergency button is reset.

The machine head is not well discharged or blocked

1. Cause:

(1) A certain section of the heater does not work, and the material is not plasticized.

(2) The operating temperature setting is low, or the molecular weight distribution of the plastic is wide and unstable.

(3) There may be foreign matter that is not easily melted.

2. Processing Method:

(1) Check the heater and replace if necessary.

(2) Verify the set temperature of each section and, if necessary, negotiate with the technician to increase the temperature setting.

(3) Clean and inspect the extrusion system and the machine head.

Main motor starting current is too high

1. Cause:

(1) The heating time is insufficient and the torque is large.

(2) A certain heater does not work.

2. Processing Method:

Apply the hand truck when driving. If it is not easy, extend the heating time or check whether the heaters are working properly.

The main motor makes an abnormal sound

1. Cause:

(1) The main motor bearing is damaged.

(2) A thyristor in the main motor thyristor rectifier circuit is damaged.

2. Processing Method:

(1) Replace the main motor bearing.

(2) Check the thyristor rectifier circuit and replace the thyristor component if necessary.