Have you ever encountered these problems in the injection molding process?

Wavy lines on plastic parts

Due to the narrow gate or other parts, when the soluble plastic pushes the cured plastic part forward, the surface will produce wavy lines.

Increase the nozzle diameter; 2. Increase the temperature of injection nozzle and die; 3. Increase the barrel temperature; 4. Speed up injection molding; 5. Slow down the injection rate; 6. Change the inlet water level of mold cooling water to keep it away from the gate; 7 expand the gate.

Crazing of plastic parts

Due to the moisture content of plastics, uneven mixing, air entrainment during injection molding, too many additives or release agents.

1. Strengthen the back pressure; 2. Slow down the injection speed; 3. Clean the barrel; 4. Increase the mold temperature; 5. Change the gate position; 6. Expand the runner and gate; 7. Baking material; 8 install an infrared light in the hopper.

Poor plastic interface

Because the temperature of the plastic is too low to melt, or because of insufficient gas discharge, more than two branches are mixed to produce FA like thin lines or bubbles.

1. Increase the material temperature; 2. Increase the nozzle temperature; 3. Increase the injection rate; 4. Cold material pool shall be set at the suture; 5. Add vent; 6. Change the gate position or increase the gate; 7. Do not use release agent; 8. Switch to low viscosity raw materials that are easy to flow.

Cavity in plastic parts

Because the surface of the plastic contacts the low-temperature mold wall during the solidification of the melt, the shrinkage is concentrated in the thick wall section, resulting in voids, or voids due to air entrainment.

Increase injection pressure and secondary pressure; 2. Prolong the injection time; 3. Reduce the curing temperature of the barrel; 4. Reduce the die wall thickness to less than 6mm, set equal wall thickness rib lines if necessary, and remove excess wall thickness; 5. Expand the gate; 6. Shorten the flow channel; 7. Even the mold temperature; 8 change the gate position to eliminate air entrapment.

Insufficient injection of plastic parts

Due to insufficient mechanical injection and plasticization performance, poor material flow or lack of material, too fine gate section, too thin mold wall or poor air leakage.

1. Increase the injection rate. If it is still insufficient, replace it with a larger machine; 2. Install anti leakage injection valve screw; 3. Increase injection pressure; 4. Improve the curing of barrel, nozzle and mold temperature; 5. Check the electric heating fault; 6 check whether the injection nozzle is blocked and increase the circulation speed; 7. Improve the mold bleeding ability; 8. Increase the gate section; 9. Increase the product wall thickness; 10. Add auxiliary line and transform material flow; 11. Select low viscosity raw materials; 12 add lubricant.

Extrusion of plastic at the clamping edge

Mold defects due to high material temperature or injection pressure, or insufficient clamping force

1. Reduce the injection pressure or barrel temperature; 2. Shorten the injection time; 3. Reduce the injection rate; 4. Use high clamping force machinery; 5. Transform the clamping surface, tighten and clean the clamping surface; 6. Switch to low viscosity raw materials.

Dents on the surface of plastic parts

Dents caused by incorrect cooling of plastic part surface

Increase the injection rate; 2. Increase the internal pressure of die groove; 3. Reduce the barrel temperature; 4. Improve injection flow; 5. Increase the injection rate; 6. Extend the injection time; 7. Make the mold temperature uniform; 8. Change the gate position; 9. Expand gate; 10 shorten the mold runner.

Plastic parts are twisted and deformed

Due to the relaxation of injection residual stress, the plastic parts are deformed and distorted.

1. Reduce injection pressure; 2. Reduce the barrel temperature; 3. Extend the cooling time; 4. Evenly adjust the wall thickness of plastic parts and the action of demoulding lock; 5. Add demoulding lock; 6. Change the gate position; 7. Even the mold temperature.

The plastic part adheres to the mold cavity

Because the die taper is fine, the injection pressure is too high or the model is poor.

1. Reduce injection pressure; 2. Reduce the barrel temperature; 3. Increase die taper; 4. Improve the model and remove the groove; 5. Adjust the mold temperature; 6. Switch to materials with good demoulding performance.

There are wrinkles or discoloration on the surface of plastic parts

The plastic decomposes due to overheating, and the olive head ring is worn

Reduce the barrel temperature; 2. Shorten the intermediate operation time; 3. Reduce the injection rate; 4. Increase the air release rate of the die; 5. Expand the gate; 6 replace the olive head and olive head ring.

Color deviation of plastic parts

Color deviation caused by temperature toner raw materials and mechanical cleaning.

1. Adjust the beer molding temperature; 2. Clean the machinery; 3. Color background deviation of raw materials; 4. Uneven mixing; 5. Conversion machinery; 6 toner deviation; 7. Different molds; 8 drying materials.

Starting point of plastic part color

Due to pigment diffusion performance or operating procedures

1 adjust the rolling time; 2. Increase oil expansion; 3. Add diffusing agent or diffusing oil; 4 sieve the toner.

Black lines on plastic parts

Black lines caused by operation, cleaning and environmental problems.

Mechanical cleaning and nozzle cleaning; 2. Reduce the amount of residual materials; 3 environmental cleaning 4 replace with olive head.

Texturing of plastic parts

Due to pigment diffusion, black lines appear during beer molding process.

1. Increase back pressure; 2. Reduce the amount of residual materials; 3. Lengthen storage; 4 adjust the temperature; 5 toner conversion; 5 use dispersant.

Plastic black spot

Black spots caused by pollution

1. Clean the machinery; 2. Clean the environment; 3. Replace raw materials; 4 check whether the pigment is contaminated.

White clouds and white spots on plastic parts

Due to temperature, mold, raw materials, toner diffusion performance and rolling procedure, white clouds and white spots are caused.

Adjust the temperature; 2. Improve the mold; 3. Convert fast flow raw materials; 4 add dispersant or oil to help; 5. If light color, check the rolling procedure.