Reasons and remedies for the defects of the hottes

  • Detail

Causes and remedies of injection molding defects

defect name characteristics of injection molding defects possible problems of injection molding machine suggested remedies differences in the size of injection molded parts changes in weight and size during injection molding exceed the production capacity of mold/injection molding machine/+ plastic combination. 1. The plastic in the input melt cartridge is uneven

2. The temperature or fluctuation range of the melt cartridge is too large

3. The capacity of the injection molding machine is too small

4. Unstable injection pressure

5. Screw resetting is unstable

6. The change of operation time and solution viscosity are inconsistent* Check whether there is enough cooling water flowing through the hopper throat to maintain the correct temperature

* check whether there are inferior or loose thermocouples

indicates that it enters the difficult deformation stage * check whether the thermocouple used with the temperature controller is of the correct type

* check the injection volume and plasticizing capacity of the injection molding machine, and then compare with the actual injection volume and hourly plastic consumption

* check whether there is stable molten padding in each operation

* check whether the backflow prevention valve leaks, and replace it if necessary

* ensure that the return position of the screw is stable after each operation, that is, no more than 0.4mm (0.016in) change

* check the inconsistency of operation time and use back pressure. The filling is insufficient, and the injection molding process is incomplete, because the mold cavity is not filled with plastic or the injection molding process lacks some details. 1. The speed of the injection molding machine is insufficient

2. There is a shortage of plastic

3. There is no screw pad left at the end of the stroke

4. Operation time changes

5. The temperature of sol cylinder is too low

6. Insufficient injection speed

7. The nozzle is partially sealed

8. The heater at the nozzle or sol cylinder cannot operate

9. According to the official of Liaoning Provincial Bureau of quality and technical supervision on November 29, the time of injection molding was too short

10. The plastic is pasted on the throat wall of the hopper

11. The injection weight or plasticizing capacity is too small* Increase injection speed

* check the amount of plastic in the hopper

* check whether the injection stroke is set correctly, and change it if necessary

* check the non-return valve for wear or cracks

* check whether the operation is stable

* increase the sol temperature

* increase back pressure

* increase injection speed

* check whether there is foreign matter or unplasticized plastic in the nozzle hole

* check the outer layer of all heaters and check whether the energy output is correct with an ammeter

* increase the cooling capacity of the hopper throat area, or reduce the temperature of the rear area of the melt cartridge

* use a larger injection molding machine. Color distribution deviation the color of injection molded parts is not uniform, that is, there are differences in intensity, colored stripes or patches. The injection molding machine is also coated with self-adhesive sol on the foothold of the mouse, and the pigment in the cylinder is not fully mixed* Increase back pressure

* reduce the temperature of the melt cartridge to obtain better plastic mixing

Copyright © 2011 JIN SHI