There are 16 kinds of faults in the plasticizing unit of the injection molding machine. How to solve them?

1. Can't shoot glue
The nozzle is blocked by foreign matters. Check whether the nozzle is blocked, clean or replace the nozzle.
The dispensing nozzle is broken. Remove the flange to check whether the rubber nozzle is broken, and replace the rubber nozzle.
The glue injection direction valve is stuck. Check whether the direction valve has 24V voltage and the coil resistance is 15-20 Ω. If it is normal, the valve is blocked. Clean the valve or replace the direction valve.
The rubber injection piston rod is broken. Loosen the rubber injection piston rod nut, check whether the piston rod is broken, and replace the piston rod.
The barrel temperature is too low. Check whether the actual temperature reaches the required melting point temperature of the material, and reset the barrel temperature.
The rubber injection piston oil seal is damaged. Check whether the piston oil seal is damaged, and replace the oil seal.
2. The starting sound of glue injection is loud
The injection speed starts too fast. Observe the change of the starting speed of glue injection and adjust the glue injection flow speed.
There is air in the oil circuit. Observe whether there is vibration in each action.
3. The sound is loud when the glue injection is stopped
The action conversion speed is too fast during glue injection. Check whether the glue injection increases the pressure holding, increases the pressure holding, adjusts the glue injection stage, and adds the melt glue delay.
4. The injection quantity is unstable
The cylinder oil seal is worn. Observe the pressure of the pressure gauge and replace the oil seal.
The rubber separating nozzle and rubber separating ring are worn. Detect out with 2 times of glue injection, and replace the three-piece set of glue nozzle.
The barrel is worn. Use the nozzle for two times to detect the wear, disassemble the material and check the wear, and replace the glue cartridge.
5. Semi-automatic glue injection action.
The advance of the launching platform is not terminated. Check whether the front of the shooting table or the mold locking travel switch is normal, and check the circuit and travel switch.
Disconnection. Check the circuit and reconnect it.
Lock mode to zero. When the hinge is straightened, the position is 0, and the zero position of the electronic ruler is readjusted.
6. During semi-automatic/full-automatic operation, the barrel temperature gradually exceeds the set value
The melt speed is too fast. Use a tachometer to test whether the screw speed is too fast and reduce the melt speed.
Excessive back pressure. Observe the product and the back pressure gauge value to reduce the back pressure as much as possible.
Friction between screw and barrel. Remove the screw and barrel, check the wear, and replace the barrel or screw.
Improper temperature setting. Check whether the actual temperature is too low and reset the temperature.
The shear heat of plastic is too large. Check the temperature rise of the front section and the middle section, reduce the speed of the melt glue and back pressure.
7. The screw makes a noise during glue melting
The drive shaft is improperly installed. Separate the screw and check if there is any sound. If there is any, remove the plane bearing and reassemble it.
The plane bearing is damaged. Separate the screw and check if there is noise in the rotating part, then replace the plane bearing.
The screw is bent. Remove the screw for inspection and replace the screw.
The screw has iron chips. Remove the screw for inspection and clean the screw.
Check the coaxiality of the adjusting screw with a dial gauge. It is normal to run out about 0.05mm.
8. Can't melt glue
Burn bearing or drive shaft burst. Separate the screw and melt the glue again, observe the sound, and replace the bearing.
The screw has iron chips. Separate the screw and barrel, check whether there is iron filings on the screw, and remove the screw for cleaning.
The melt valve is blocked. Use the hexagonal spoon to top the valve core to see if it moves and clean the solenoid valve.
The glue motor is damaged. Separate the glue motor, and replace or repair the glue motor when the glue does not rotate.
Burn out the heating ring. Check whether it is normal with a multimeter and replace the heating ring.
The plug is loose. Check whether the melt oil plug has poor contact, tighten the plug, and check whether there is 24 power supply.
9. The back pressure cannot be adjusted during glue melting
The back pressure valve is broken. Increase the back pressure during blanking, check whether the screw is backward, and clean the back pressure valve.
10. The product has black spots
The screw has carbon deposit. Check and clean the screw and barrel.
There is carbon deposit in the material barrel and the auxiliary machine is not clean. Check whether the feeding machine has dust, polish the material barrel and clean the auxiliary machine.
The nozzle assembly is corroded. Check the nozzle and replace the nozzle assembly.
There is carbon deposit on the flange and nozzle. Clean and replace.
Raw materials are dirty. Check raw materials and replace raw materials.
The temperature is too high, and the melt back pressure is too high. Check the temperature of each section, reduce temperature and back pressure.
11. Poor screw color mixing
Questions between materials. Check the toner quality and replace the material.
The temperature is too low. Check the actual temperature and the required temperature of the material, and increase the temperature.
If the back pressure is too low, check the back pressure and increase the back pressure.
The mixing time is short. Extend mixing time or replace with mixing head.
The speed is too low. Check the screw speed and increase the screw speed.
12. No rubber extraction action
High back pressure. Check the spray speed of the nozzle during manual glue melting to reduce the back pressure.
Disconnection. The rubber extraction valve is disconnected.
The direction valve spool is not flexible. Press the valve core with an Allen wrench to check whether it moves freely and clean the valve core.
13. When melting glue, the motor swings its tail
The bearing is damaged. Observe if there is any abnormal sound when the glue is melted, and replace the bearing.
The inclined ball bearing is not adjusted properly. Observe whether the transmission shaft swings and readjust the clearance.
Screw deformation. Separate the screw and observe the rotation of the transmission shaft, and replace the screw.
The copper sleeve of the rear plate of the shooting table is worn and two guide rods are deformed or the fixing screws are loose. Observe whether copper powder is grinded from the copper sleeve of the second plate, and replace the copper sleeve.
14. Glue injection twice
The nozzle aperture is too small, and the resistance is too large when injecting glue.
The nozzle heating ring is damaged, check the heating ring or replace it.
Check whether the pressure flow output is normalized.
15. Cause of screw breakage
The shooting is not synchronized, and the shooting synchronization is adjusted ± 0.05
The rubber injection cylinder is not synchronized, adjust the rubber injection cylinder synchronization ± 0.05
Raw materials do not match the performance of injection molding machine screw.
The temperature did not reach the melting point of the material used.
Turn the screw when the temperature is just reached.
If the heating cylinder is burnt out and not heated, check whether it has anti-cooling function and replace the heating cylinder.
16. Cannot adjust the mold
The mechanical level and parallelism are out of tolerance. Check and adjust the parallelism and levelness with the level gauge.
The gap between the pressing plate and the mold adjusting screw is too small. Measure with a feeler gauge, adjust the clearance between the pressing plate and the nut, and the clearance between the adjusting nut and the pressing plate (clearance ≤ 0.05m).
Burn the nut to check whether the nut can rotate and heat up and whether there is iron powder coming out. Replace the nut.
Adjust the upper and lower support plates. Remove the support plate lock nut for inspection and adjust the adjusting nut.
The I/O board is broken. Check whether there is signal at the output point on the computer page and repair the electronic board.
The mold adjusting valve core is stuck. Remove the valve for inspection and cleaning.
The mold adjusting motor is broken. Check the oil motor. Replace or repair the oil motor.