塑胶产品注塑成型常见问题及改善对策（Plastic products injection molding common problems and improvement measures）.doc

塑胶产品注塑成型常见问题及改善对策（Plastic products injection molding common problems and improvement measures） Cooling the parts in hot water. 3, how to avoid product dents and pores? Product dents are usually due to insufficient force on the product, inadequate material filling and unreasonable design of the product. The dents often appear in the thick wall which is close to the thin wall. The porosity is caused by insufficient plastic in the mold cavity, and the outer ring plastic is cooled and solidified, and the internal plastic shrinks to form a vacuum. Most likely due to the fact that hygroscopic materials are not dry properly, and that residual monomers and other compounds are present in the material. Determine the cause of the pores, as long as the observation of plastic bubbles in the mold when the instantaneous appearance or cooling occurs. If the mold appears when it is instantaneous, it is mostly the material problem. If it is cooled, it belongs to the mould or injection molding condition. (1) material problems: Drying material Add lubricant Reduce the volatile matter in the material (2) injection molding condition Insufficient injection; Increasing injection pressure; Increase injection time; Increase the total pressure time; Increasing injection speed; The increase of the injection cycle; The reason causing abnormal operation of the injection cycle. (3) temperature problem Too much material causes excessive shrinkage; The material is too cold, resulting in insufficient compaction; The mold temperature is too high due to mold wall material can be quickly cured; The mold temperature is too low, resulting in insufficient mold filling; Mould has partial over hot spot; Changing the cooling scheme. (4) die problem; Gate enlargement; Enlarge distributary channel; Increase mainstream road; Increase nozzle hole; Improved mold exhaust; The balance filling rate; The filling material flow to avoid interruption; The gate feeding arrangement of WIP thick wall parts; If it is possib