Top 10 common problems and solutions in the production process of PVC injection molding products
1. Burning burnt stripes from the gate:
Reduce the injection speed; enlarge the gate or nozzle diameter; reduce the injection pressure; increase the material temperature (ie, the mixture of material temperature, such as resin powder, calcium carbonate, PVC composite stabilizer, etc.) to reduce the viscosity.
2. There are burnt stripes in the center of the main road:
Reduce the screw speed or back pressure; reduce the temperature of the barrel head; polish the screw head or the inner surface of the barrel head; use an eccentric screw head.
3. Discoloration or charring occurs at a certain point or seam line in the mold:
Reduce injection speed; improve mold venting; polish or round the flow path and the sharp corner of the gate.
4. There are scattered black particles on the product:
Clean the screw and barrel; reduce the injection speed.
5, the material is discolored or partially burnt:
Check if the temperature controller is qualified; pre-clean the barrel until the color is normal, if it is still abnormal, clean the screw and barrel; reduce the screw speed or back pressure; lower the temperature of the electric heating ring; check the gap between the screw and the barrel.
6. Red spots appear around the gate:
Increase the size of the main gate and nozzle; reduce the nozzle temperature; reduce the injection speed and smooth the flow path and gate to increase the mold temperature; change the gate position or increase the number of gates.
7. Umbrella stripes or silver streaks appear on the surface near the gate of the product:
Reduce the material temperature; reduce the injection speed; reduce the nozzle temperature; dry the material.
8, poor seam line:
Appropriately increase the material temperature; increase the injection speed; increase the holding pressure m; increase the holding pressure; change the mold temperature; improve the exhaust; change the gate position or the gate size.
Ensure that the screw has been thoroughly cleaned; increase the material temperature; increase the injection speed; increase the gate size.
10, product warpage:
Reduce the mold temperature; reduce the injection pressure and holding pressure; check the uniformity of the wall thickness of the product; use the anti-shrink fixing clamp.