During the processing of pallet plastic parts, common defects include flash, shrinkage, bubbles, deformation, dimensional deviation, stress cracking and uneven surface gloss.
Flash is usually caused by excessive injection pressure, loose mold clamping or excessive plastic fluidity. The solution is to appropriately reduce the injection pressure, check and repair the mold clamping surface to make it well sealed, and consider using plastic raw materials with moderate fluidity.
Sink marks often occur due to insufficient pressure holding or uneven cooling. The pressure holding time and pressure should be increased, and the design of the cooling system should be optimized to ensure uniform cooling of all parts of the pallet, such as reasonable arrangement of cooling water channels to improve cooling efficiency.
The cause of bubbles may be insufficient drying of the plastic or too fast injection speed. The plastic should be fully dried to reduce the water content, and the injection speed should be appropriately reduced to allow enough time for the gas to be discharged.
Deformation problems generally arise from uneven cooling, improper demolding or unreasonable product structure. The cooling system needs to be improved to ensure uniform cooling, optimize the demolding mechanism to ensure smooth demolding, and optimize the product structure to enhance its rigidity.
Dimensional deviation may be caused by mold wear, unstable injection molding process parameters or fluctuations in plastic shrinkage. The mold should be maintained regularly, injection molding process parameters such as temperature, pressure, time, etc. should be accurately controlled, and plastic raw materials with stable quality and consistent shrinkage should be selected.
Stress cracking is mostly caused by large demoulding resistance and internal stress concentration of the product. The demoulding resistance can be reduced by optimizing the mold demoulding slope, and the product can be annealed to eliminate internal stress.
Uneven surface gloss may be caused by inconsistent mold surface roughness or improper injection molding process. The mold surface needs to be polished to make it uniformly rough, and the injection molding process parameters should be adjusted, such as increasing the injection molding temperature and mold temperature, to improve the fluidity and filling effect of the plastic.
Through a detailed analysis of various defects in the pallet plastic parts processing process and taking targeted solutions, it is possible to effectively improve product quality, reduce scrap rate, improve production efficiency, meet the market demand for high-quality pallet plastic parts processing, and promote the healthy development of the plastic processing industry.
