{"id":431,"date":"2022-03-03T11:30:30","date_gmt":"2022-03-03T03:30:30","guid":{"rendered":"https:\/\/www.fuhrung.com\/technical-blog\/?p=431"},"modified":"2023-01-30T23:42:01","modified_gmt":"2023-01-30T15:42:01","slug":"summary-of-faults-and-countermeasures-for-injection-molding-of-polyolefin-plastics","status":"publish","type":"post","link":"https:\/\/www.fuhrung.com\/technical-blog\/summary-of-faults-and-countermeasures-for-injection-molding-of-polyolefin-plastics.html","title":{"rendered":"Summary of faults and Countermeasures for injection molding of polyolefin plastics"},"content":{"rendered":"\n<p>Underinjection<\/p>\n\n\n\n<p>(1) Melt temperature is too low. The temperature of barrel and nozzle shall be properly increased.<\/p>\n\n\n\n<p>(2) The molding cycle is too short. It shall be extended appropriately.<\/p>\n\n\n\n<p>(3) The injection pressure is low. It should be properly improved.<\/p>\n\n\n\n<p>(4) The injection speed is too slow. It should be accelerated appropriately.<\/p>\n\n\n\n<p>(5) The pressure holding time is too short. It shall be extended appropriately.<\/p>\n\n\n\n<p>(6) Insufficient supply. The feeding volume shall be increased.<\/p>\n\n\n\n<p>(7) Screw back pressure is low. It should be properly improved.<\/p>\n\n\n\n<p>(8) The structural size of gating system is too small. Gate and runner sections shall be suitably enlarged.<\/p>\n\n\n\n<p>(9) Poor mold exhaust. Mold exhaust shall be increased.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Insufficient die strength. The die rigidity shall be improved as much as possible.<\/li>\n<\/ul>\n\n\n\n<p>molding flash<\/p>\n\n\n\n<p>(1) The melt temperature is too high. The temperature of barrel and nozzle shall be properly reduced.<\/p>\n\n\n\n<p>(2) The injection pressure is too high. It shall be reduced appropriately.<\/p>\n\n\n\n<p>(3) The injection speed is too fast. Slow down properly.<\/p>\n\n\n\n<p>(4) The pressure holding time is too long. It shall be shortened appropriately.<\/p>\n\n\n\n<p>(5) Excessive feed. The feeding amount shall be appropriately reduced.<\/p>\n\n\n\n<p>(6) Insufficient clamping force. The clamping force shall be increased.<\/p>\n\n\n\n<p>(7) Insufficient die strength. The die rigidity shall be improved as much as possible.<\/p>\n\n\n\n<p>(8) The setting of inserts is unreasonable. It shall be adjusted appropriately.<\/p>\n\n\n\n<p>(9) The gate section is large. It shall be reduced appropriately.<\/p>\n\n\n\n<p>(10) The mold is poorly installed and the benchmark is not aligned. The mold should be reassembled.<\/p>\n\n\n\n<p>Bubble<\/p>\n\n\n\n<p>(1) The melt temperature is too high. The temperature of barrel and nozzle shall be properly reduced.<\/p>\n\n\n\n<p>(2) The molding cycle is too long. It shall be shortened appropriately.<\/p>\n\n\n\n<p>(3) The injection pressure is low. It should be properly improved.<\/p>\n\n\n\n<p>(4) The injection speed is too fast. Slow down properly.<\/p>\n\n\n\n<p>(5) Pressure holding time is too short. It shall be extended appropriately.<\/p>\n\n\n\n<p>(6) The mold temperature is uneven. The mold cooling system and flow shall be set reasonably.<\/p>\n\n\n\n<p>(7) Poor mold exhaust. Mold exhaust shall be increased.<\/p>\n\n\n\n<p>(8) The product structure design is unreasonable and the wall is too thick. Adjustments should be made where possible.<\/p>\n\n\n\n<p>(9) Gate section is too small. It shall be properly enlarged.<\/p>\n\n\n\n<p>Warpage deformation<\/p>\n\n\n\n<p>(1) Melt temperature is too low. The barrel temperature shall be properly increased.<\/p>\n\n\n\n<p>(2) The molding cycle is short. It shall be extended appropriately.<\/p>\n\n\n\n<p>(3) The injection pressure is too high. It shall be reduced appropriately.<\/p>\n\n\n\n<p>(4) The injection speed is too fast. Slow down properly.<\/p>\n\n\n\n<p>(5) The pressure holding time is too long. It shall be shortened appropriately.<\/p>\n\n\n\n<p>(6) The mold temperature is uneven. The mold cooling system and flow shall be set reasonably.<\/p>\n\n\n\n<p>(7) Gate section size is too small. It shall be properly enlarged.<\/p>\n\n\n\n<p>(8) The setting of ejector is unreasonable. The ejection cross-sectional area and ejection point shall be increased as much as possible.<\/p>\n\n\n\n<p>(9) Insufficient die strength. The die rigidity shall be improved as much as possible.<\/p>\n\n\n\n<p>Shrinkage depression<\/p>\n\n\n\n<p>(1) The melt temperature is too high. The barrel temperature shall be properly reduced.<\/p>\n\n\n\n<p>(2) The injection pressure is too low. It should be properly improved.<\/p>\n\n\n\n<p>(3) Mold temperature is too high. It shall be reduced appropriately.<\/p>\n\n\n\n<p>(4) The product wall is too thick. Adjustments should be made where possible.<\/p>\n\n\n\n<p>(5) Gate section size is too small. It shall be properly enlarged.<\/p>\n\n\n\n<p>(6) The molding cycle is too short. It shall be extended appropriately.<\/p>\n\n\n\n<p>(7) Pressure holding time is too short. It shall be extended appropriately.<\/p>\n\n\n\n<p>Weld mark<\/p>\n\n\n\n<p>(1) Melt temperature is too low. The temperature of barrel and nozzle shall be properly increased.<\/p>\n\n\n\n<p>(2) The injection pressure is too low. It should be properly improved.<\/p>\n\n\n\n<p>(3) The injection speed is too slow. It should be accelerated appropriately.<\/p>\n\n\n\n<p>(4) Mold temperature is too low. It should be properly improved.<\/p>\n\n\n\n<p>(5) The product structure design is unreasonable or the wall is too thin. Adjustments should be made where possible.<\/p>\n\n\n\n<p>(6) The structural size of gating system is too small. Gate and runner sections shall be suitably enlarged.<\/p>\n\n\n\n<p>(7) The cold cavity in the die is too small. It shall be properly enlarged.<\/p>\n\n\n\n<p>(8) Foreign matters and impurities are mixed in the raw material. It shall be removed.<\/p>\n\n\n\n<p>(9) The amount of release agent is too much. Its dosage should be minimized.<\/p>\n\n\n\n<p>(10) Uneven coloring of raw materials. The coloring of raw materials shall be uniform.<\/p>\n\n\n\n<p>Scorched black lines<\/p>\n\n\n\n<p>(1) The melt temperature is too high, resulting in overheating decomposition. The barrel temperature shall be properly reduced.<\/p>\n\n\n\n<p>(2) The molding cycle is too long. It shall be shortened appropriately.<\/p>\n\n\n\n<p>(3) The injection speed is too fast. Slow down properly.<\/p>\n\n\n\n<p>(4) Screw back pressure is too high. It shall be reduced appropriately.<\/p>\n\n\n\n<p>(5) Gate section size is too small. It shall be properly enlarged.<\/p>\n\n\n\n<p>(6) Poor mold exhaust. Mold exhaust shall be increased.<\/p>\n\n\n\n<p>(7) Poor drying of raw materials. The drying temperature should be increased and the drying time should be prolonged.<\/p>\n\n\n\n<p>(8) Too much release agent. Its dosage should be minimized.<\/p>\n\n\n\n<p>Surface scratch<\/p>\n\n\n\n<p>(1) The injection pressure is too high. It shall be reduced appropriately.<\/p>\n\n\n\n<p>(2) The pressure holding time is too long. It shall be shortened appropriately.<\/p>\n\n\n\n<p>(3) Mold temperature is too low. It should be properly improved.<\/p>\n\n\n\n<p>(4) The setting of ejector is unreasonable. The ejection cross-sectional area and ejection point shall be increased as much as possible.<\/p>\n\n\n\n<p>(5) Insufficient demoulding slope. It shall be increased appropriately.<\/p>\n\n\n\n<p>Low Gloss<\/p>\n\n\n\n<p>(1) The melt temperature is low. The temperature of barrel and nozzle shall be properly increased.<\/p>\n\n\n\n<p>(2) The molding cycle is too long. It shall be shortened appropriately.<\/p>\n\n\n\n<p>(3) The mold temperature is low. It should be properly improved.<\/p>\n\n\n\n<p>(4) The structural size of gating system is too small. Gate and runner sections shall be suitably enlarged.<\/p>\n\n\n\n<p>(5) Poor mold exhaust. Mold exhaust shall be increased.<\/p>\n\n\n\n<p>(6) Foreign matters and impurities are mixed in the raw material. Raw materials shall be removed or replaced.<\/p>\n\n\n\n<p>(7) Too much release agent. Its dosage should be minimized.<\/p>\n\n\n\n<p>Uneven color<\/p>\n\n\n\n<p>(1) Barrel temperature too high. The barrel temperature shall be properly reduced.<\/p>\n\n\n\n<p>(2) The molding cycle is too long. It shall be shortened appropriately.<\/p>\n\n\n\n<p>(3) Screw back pressure is too low. It should be properly improved.<\/p>\n\n\n\n<p>(4) Uneven coloring of raw materials. The coloring of raw materials shall be uniform.<\/p>\n\n\n\n<p>Delamination stripping<\/p>\n\n\n\n<p>(1) Melt temperature is too low. The temperature of barrel and nozzle shall be properly increased.<\/p>\n\n\n\n<p>(2) Screw back pressure is too high. It shall be reduced appropriately.<\/p>\n\n\n\n<p>(3) Foreign matters and impurities are mixed in the raw material. It shall be removed.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"450\" src=\"https:\/\/www.fuhrung.com\/technical-blog\/wp-content\/uploads\/2022\/03\/0303.jpg\" alt=\"\" class=\"wp-image-432\" srcset=\"https:\/\/www.fuhrung.com\/technical-blog\/wp-content\/uploads\/2022\/03\/0303.jpg 600w, https:\/\/www.fuhrung.com\/technical-blog\/wp-content\/uploads\/2022\/03\/0303-300x225.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Underinjection (1) Melt&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-431","post","type-post","status-publish","format-standard","hentry","category-technical"],"_links":{"self":[{"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/posts\/431","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/comments?post=431"}],"version-history":[{"count":3,"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/posts\/431\/revisions"}],"predecessor-version":[{"id":620,"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/posts\/431\/revisions\/620"}],"wp:attachment":[{"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/media?parent=431"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/categories?post=431"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fuhrung.com\/technical-blog\/wp-json\/wp\/v2\/tags?post=431"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}