塑胶及模具基础知识(三)（Basic knowledge of plastics and molds (three)）.doc

塑胶及模具基础知识(三)（Basic knowledge of plastics and molds (three)） Plastic and mold Basics (three).Txt yesterday was a voided check; tomorrow is an outstanding promissory note; only cash today can be cashed at any time. People always love to deceive ourselves, because it more easily than to deceive others. 1, insufficient filling (short, shot) When the melted plastic is injected into the mold cavity, it is cooled and hardened when it has not been filled. The phenomenon of insufficient material is called insufficient filling. The reasons and Countermeasures of caused by the machine tool Cause and countermeasure 1. the injection capability is insufficient and the injection capability of the machine will be confirmed 2. injection pressure is too low to raise pressure 3. raw material temperature is low, poor fluidity, confirm heating cylinder temperature and raise injection pressure 4. raw material supply is insufficient, increase material quantity 5. injection speed increase rate of fire 6. injection nozzle, big resistance, confirm aperture and electric heating ability 7. screw feed bad manual feed 8., raw material falling, because it is difficult to confirm the removal of raw materials, and reduce the feed temperature 9. screw injection counter current update check ring (backstop ring) The reasons and Countermeasures Caused by the mold. Cause and countermeasure 1., the design of the soup mouth is not equally calculated and revised 2. 、 soup port \ runner \ gate design is too small, re calculated and increased size 3. cold material storage, blocking, removal of obstruction 4. bad exhaust additional air escape design 5. mold temperature low to reduce the cooling water temperature 6. the product thickness is too thin to check the exhaust or increase thickness design 7. hot runner blocked, not pass, check circuit and temperature, and overhaul 8. die cooling improperly, confirm waterway system and modify it Causes and Countermeasures - caused by raw materials Cause and countermea