Troubleshooting Methods:
1) Nozzle blockage. Check the nozzle for blockage; clean or replace it.
2) Broken dispensing nozzle. Disassemble the flange to check the dispensing nozzle for breakage; replace it if necessary.
3) Sticking injection directional valve. Check if the directional valve has 24V voltage and the coil resistance is 15-20 ohms. If normal, the valve is blocked; clean or replace it.
4) Broken injection piston rod. Loosen the piston rod nut and check if the piston rod is broken; replace it if necessary.
5) Low barrel temperature. Check if the actual temperature reaches the required melting point of the material; reset the barrel temperature.
6) Damaged injection piston oil seal. Check if the piston oil seal is damaged; replace it if necessary.
2. Loud injection start-up noise
Troubleshooting Methods:
1) Injection speed starts too quickly. Observe the change in injection speed at start-up and adjust the injection flow rate.
2) Air in the oil circuit. Observe whether there is vibration in each action.
3. Loud noise when transitioning from injection to melting.
Solution:
1) The action transition speed is too fast during injection. Check if the holding pressure is increased during injection. If so, increase the holding pressure, adjust the injection stage, and add a melting delay.
4. Unstable injection volume.
Solution:
1) Worn hydraulic cylinder oil seal. Observe the pressure gauge and replace the oil seal.
2) Worn dispensing nozzle and dispensing ring. Detect this with two injection tests and replace the dispensing nozzle set.
3) Worn barrel. Detect this with two injection tests, disassemble the barrel to check for wear, and replace the melting barrel.
5. No injection action in semi-automatic operation.
Solution:
1) The injection stage does not stop advancing. Check if the limit switch at the front of the injection stage or the mold locking position is normal. Check the wiring and limit switches.
2) Broken wiring. Check the wiring and rewire.
3) Mold locking returns to zero. 6. When the machine hinge is fully extended, the position is 0. Readjust the zero position of the electronic ruler.
7. During semi/fully automatic operation, the barrel temperature gradually exceeds the set value.
Troubleshooting:
1) The melting speed is too fast. Use a tachometer to test if the screw speed is too fast, and reduce the melting speed.
2) The back pressure is too high. Observe the product and the back pressure gauge value, and reduce the back pressure as much as possible.
3) Friction between the screw and the barrel. Disassemble the screw and barrel, check for wear, and replace the barrel or screw.
4) Inappropriate temperature setting. Check if the actual temperature is too low, and reset the temperature.
5) Excessive shear heat on the plastic. Check the temperature rise in the front and middle sections, and reduce the melting speed and back pressure.
7. The screw makes noise during melting.
Troubleshooting:
1) Improper installation of the drive shaft. Separate the screw and rotate it to check for noise. If there is noise, disassemble the plane bearing and reassemble it.
2) The plane bearing is faulty. 1) If there is noise when checking the rotating parts after separating the screw, replace the plane bearing.
2) If the screw is bent, remove the screw, inspect it, and replace it if necessary.
3) If there are metal filings on the screw, disassemble the screw, inspect it, and clean it.
4) If there are metal filings on the screw, use a dial indicator to check the coaxiality of the screw. A runout of about 0.05mm is normal.
8. Cannot Melt Adhesive
Troubleshooting:
1) If the bearing is burnt out or the drive shaft is cracked, separate the screw, try melting the adhesive again, and observe the sound. Replace the bearing if necessary.
2) If there are metal filings on the screw, separate the screw from the barrel, check the screw for metal filings, and clean it if necessary.
3) If the melting valve is blocked, use a hex key to check if the valve core moves. Clean the solenoid valve.
4) If the melting motor is damaged, separate the melting motor. If the melting motor does not turn, replace or repair it.
5) If the heating coil is burnt out, use a multimeter to check if it is normal. Replace the heating coil if necessary.
6) Loose plug. Check if the plug for poor contact in the melt glue system; tighten the plug and check for 24-hour power.
9. Back pressure cannot be adjusted during melt glue application.
Solutions:
1) Faulty back pressure valve. Increase back pressure during material feeding, check if the screw is retracting, and clean the back pressure valve.
10. Black spots on the product.
Solutions:
1) Carbon buildup on the screw. Check and clean the screw and barrel.
2) Carbon buildup on the barrel and unclean auxiliary equipment. Check the feeder for dust, polish the barrel, and clean the auxiliary equipment.
3) Corrosion of the dispensing nozzle assembly. Check the dispensing nozzle and replace the assembly.
4) Carbon buildup on the flange and nozzle. Clean and replace.
5) Unclean raw materials. Check and replace the raw materials.
6) Overheating and excessive melt glue back pressure. Check the temperature of each section and reduce the temperature and back pressure.
11. Poor Screw Color Mixing
Troubleshooting:
1) Material Incompatibility. Check the quality of the color powder and replace the material.
2) Temperature Too Low. Check the actual temperature against the required temperature of the material and increase the temperature.
3) Back Pressure Too Low. Check the back pressure and increase it.
4) Short Mixing Time. Increase the mixing time or replace the mixing head.
5) Screw Speed Too Low. Check the screw speed and increase it.
12. No Glue Extraction Action
Troubleshooting:
1) High Back Pressure. Check the nozzle spray speed during manual melting and reduce the back pressure.
2) Broken Wire. Check for a broken wire in the glue extraction valve.
3) Inflexible Directional Valve Core. Use an Allen wrench to check if the valve core moves freely and clean it.
13. Motor Wobble During Melting
Troubleshooting:
1) Damaged Bearing. Observe for abnormal noises during melting and replace the bearing. 2) Improper adjustment of the ball bearing. Observe whether the drive shaft wobbles and readjust the clearance.
3) Screw deformation. Separate the screw and observe the rotation of the drive shaft; replace the screw if necessary.
4) Wear on the copper bushing of the injection unit's rear plate, deformation of the two guide rods, or loose fixing screws. Observe whether copper powder is worn out from the copper bushing of the two plates; replace the copper bushing if necessary.
14. Two injection actions
1) The nozzle orifice diameter is too small, resulting in excessive resistance during injection.
2) The nozzle heating coil is faulty; check or replace the heating coil.
3) Check if the pressure and flow output are normal.
15. Causes of screw breakage
1) Injection movement is not synchronized; adjust the injection movement synchronization ±0.05.
2) Injection cylinder is not synchronized; adjust the injection cylinder synchronization ±0.05.
3) The raw material is incompatible with the performance of the injection molding machine screw.
4) The temperature has not reached the melting point of the material used.
5) The screw is rotated just as the temperature is reached. 6) Heating element burns out and stops heating. Check for anti-cold function and replace the heating element.
16. Cannot adjust mold
Troubleshooting:
1) Mechanical level and parallelism are out of tolerance. Check with a level and square, and adjust the parallelism and level.
2) The gap between the pressure plate and the adjusting nut is too small. Measure with a feeler gauge and adjust the gap between the pressure plate and the nut. The gap between the adjusting nut and the pressure plate should be ≤0.05mm.
3) Burnt nut. Check if the nut can rotate and if there is any iron powder coming out. Replace the nut.
4) Upper and lower support plate adjustment. Disassemble the support plate, check the locking nut, and adjust the adjusting nut.
5) I/O board failure. Check if there is a signal at the output point on the computer screen. Repair the electronic board.
6) Adjusting valve core stuck. Remove the valve, check, and clean the valve.
7) Adjusting motor failure. Check the hydraulic motor. Replace or repair the hydraulic motor.
