1. Vacuum value set too low. Increase the vacuum value.
2. Cooling water temperature too high. Reduce the temperature of the cooling water.
3. The speed of the haul-off unit is too fast. Reduce the speed of the haul-off unit.
4. Large shrinkage of the raw material used by the customer. Replace the raw materials.
5. The inner hole of the calibration sleeve is too small. Replace the calibration sleeve with a new one.

1. The vacuum value is set too high. Decrease the vacuum value. 2. Cooling water temperature is too high. Reduce the temperature of the cooling water. 3. The haul-off unit speed is too slow. Increase the speed of the haul-off unit. 4. Small shrinkage of the raw material used by the customer. Replace the raw materials. 5. The inner hole of the calibration sleeve is too large. Replace the calibration sleeve with a new one.

1.The temperature of the barrel or mold is too high.Reduce the temperature and retest.
2. Connecting section and filter plate not cleaned. Disassemble the connecting section and clean the inside.
3. Poor thermal stability or less stabilizer in the raw material. Check the formula and material.
4. The set temperature does not match the actual temperature. Check the installation of thermocouple, or replace with a new thermocouple test.

1. Uneven wall thickness of pipes. Adjust the mold discharge gap to ensure uniform wall thickness of the pipe.
2. Uneven temperature around the mold, and fast or slow discharging of materials.Check heater for damage.
3. The center of the machine head, cooling water tank, hauling, cutting and other equipment is not in the same straight line. Adjust equipment straightness.

1. Die lip and die core center is not aligned. Re-adjust the die lip to be concentric with the die core.
2. Uneven temperature of the mold, when diecharging, some are fast or some are slow. Check heater for damage.
3. Abnormal slippage of haul-off unit, causing the pipe diameter to fluctuate between large and small. Repair hauling equipment and make it work normally.
4. Unstable compressed air and vacuum degree. Stabilize compressed air and vacuum degree.

1. Screw temperature is too high. Reduce the setting temperature of the barrel heater and the core unit.
2. Screw speed is too fast. Slow down the screw speed.

Raw material is damp. Dry the raw material before putting it back into production.

1. Impurities in the raw material. Replace the raw material with one free of impurities.
2. The temperature of the die core is too low. Increase the die core temperature.
3. Cylinder temperature is too low. Increase the barrel temperature.
4. Hauling speed is too fast. Slow down the haul-off speed.

1. The temperature of the die core is too low. Increase the die core temperature.
2. Cylinder temperature is too low. Increase the barrel temperature.
3. Screw temperature is too high. Decrease screw temperature.

1. Uneven temperature around the die lip. Check heater for damage.
2. Cooling water is too hot. Check the temperature of the cooling water and increase the flow rate of the cooling water.
3. Hauling speed is too slow.Increase the haul-off speed.

1. The temperature of the die lip is too low. Increase the die lip temperature.
2. Die lip temperatureis too high, no luster and roughness. Decrease the die lip temperature

1. Inappropriate temperature setting.Adjust the set temperature. 2. Improper process formula. Change the process formula. 3. Large gap between screw and barrel. Adjust the gap

1.The PLC CPU unit is not in the “RUN” state.Turn the CPU's run switch to the run position.
2.The communication cable between the HMI and PLC is not in good contact with the X-wire or the connector. Check that the connecting wires and communication connectors between the HMI and PLC are good.
3.The communication port of HMI or PLC is damaged. Replace HMI or PLC

Incorrect parameter settings in the HMI setup page. Enter the HMI parameter setting page with the administrator password, check whether the maximum speed setting of the extruder (refiling machine, haul-off) is correct, and correct it.

1. The inverter cooling fan is damaged. Replace the fan.
2. The inverter temperature detection sensor is damaged, resulting in the fan not rotating. Send it back to the manufacturer for repair or find an agent to replace the parts.
3. The cooling air conditioner or fan of the inverter cabinet is abnormal. Clean the filters of the air conditioner and fan, and check whether the air conditioner is cooled properly.

The HMI factory setting parameters are lost. Enter the HMI parameter setting page with the administrator password.

1.The main board of the inverter is damaged.Send it back to the manufacturer for repair or find an agent to replace the parts.
2. Damage to the inverter. Send it back to the manufacturer for repair.

The thermocouple wire in the temperature control area is open circuited. Check whether the thermocouple wires and connectors of the relevant temperature control area are in good contact.

1. Poor contact of the 0~10V connection wire. Check if the 0~10V wiring is loose, reconnect the wires.
2. Incorrect setting of parameters related to speed giving of the inverter. Set the correct parameters according to the electrical operating instructions provided by Liansu.
3. Incorrect setting of parameters related to speed giving of the inverter. Remove the 0 ~ 10V line between the PLC and the inverter, use a multimeter to measure the PLC module 0 ~ 10v port to see whether there is voltage output, if not, that this module is damaged.

1. Incorrect setting of the dial switches of the communication card of the inverter. Set the correct dialing code according to the circuit diagram provided by Liansu.
2. Wrong setting of the parameters of the inverter. Set the correct parameters according to the electrical operating instructions provided by Liansu.
3. Damage to the communication card of the inverter. Observe whether the running light of the display panel of the inverter is flashing, if not, please replace the communication card of the inverter.

1. Forced start of the extruder due to insufficient barrel temperature or insufficient heat preservation time. Wait patiently for the temperature of each zone of the barrel to reach the set value and the corresponding heat preservation time before starting the extruder.
2. The speed is increased too fast. Slowly increase the screw speed.
3. Whether the material and process are changed. Check if the material with poor fluidity has been replaced.
4. Whether there is abnormal noise in the transmission of the gearbox. Check whether the gears of the gearbox have obvious vibration or abnormal sound, whether the oil circuit lubrication and cooling are normal.
5. Whether the inverter parameters are set correctly. Set the correct inverter parameters according to the electrical operating instructions provided by Liansu.

1. Whether the refilling motor continues to rotate. Check the control circuit.
2. Large wear on the feeding screw. Replace the feeding screw

1. Damaged gears. Replace gears
2. Bearing damage. Replace bearings

1. Cooling water clogging. Replace bearings.
2. Lubrication oil is not qualified. Replace lubricating oil.
3. Gear or bearing problem.Check gears and bearings.

1. Vacuum seat not installed properly.Install vacuum seat.
2. Damaged sealing ring. Replace sealling ring.
3. Air leakage in piping system. Replace sealling ring.
4. Damaged vacuum pump. Replace vacuum pump

1. Insufficient pressure on the compression cylinder. Increase the air pressure of the air source.
2. Aging and hardening of the rubber block. Replace the rubber block.
3. Hualing motor not strong enough. Replace motor or reducer.

1. Nylon guides on the vaterpillars are worn out. Replace nylon guides.
2. Nylon guides on the vaterpillars are worn out. Adjust drive parameters or replace motor.

1. PLC does not receive signal from auto selector switch or start button. Check auto selector switch, start button and related wiring.
2. Cutting machine clamping cylinder not at original position. Check cylinder home switch and related wiring.
3. Cutting blade not at original position.Check cutting blade home switch and related wiring.
4. Cutting follow-up limit switch malfunctioning.Check the limit switch of the follow-up trolley and the related wiring.
5. Cutting trolley not at original position. Check the home switch of the follow-up trolley and related wiring.
6. Cutting emergency stop is pressed.Reset the emergency stop switch.
7. Alarm exists in the drive of the cutting machine.Reset drive alarms and check the cause according to the alarm code.

1. PLC does not receive a signal from the automatic selector switch or start button. Check automatic selector switch, start button and related wiring.
2. The mixer's cylinder cover safety switch is not closed. Check the cylinder cover safety switch and related wiring.
3. The PLC does not receive a signal from the mixer's discharge valve sensor to close. Check that the discharge valve is properly closed and that the corresponding sensors and wiring are in good condition.
4. The temperature sensor of the mixer detects a temperature that is too high or the sensor is damaged, resulting in the mixer exceeding the temperature protection limit. Check the temperature sensor and related wiring for correctness and goodness.
5. Whether there is an alarm in the inverter. Reset drive alarms and check the cause according to the alarm code.
6. The parameters of the inverter are set incorrectly. Set the correct parameters according to the electrical operation manual provided by Liansu.