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）

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1、塑胶产品注塑成型常见问题及改善对策（Plasticproductsinjectionmoldingcommonproblemsandimprovementmeasures）Coolingthepartsinhotwater.3,howtoavoidproductdentsandpores?Productdentsareusuallyduetoinsufficientforceontheproduct,inadequatematerialfillingandunreasonabledesignoftheproduct.Thedentsoftenappearintheth

2、ickwallwhichisclosetothethinwall.Theporosityiscausedbyinsufficientplasticinthemoldcavity,andtheouterringplasticiscooledandsolidified,andtheinternalplasticshrinkstoformavacuum.Mostlikelyduetothefactthathygroscopicmaterialsarenotdryproperly,andthatresidualmonomersandothercompoundsareprese

3、ntinthematerial.Determinethecauseofthepores,aslongastheobservationofplasticbubblesinthemoldwhentheinstantaneousappearanceorcoolingoccurs.Ifthemoldappearswhenitisinstantaneous,itismostlythematerialproblem.Ifitiscooled,itbelongstothemouldorinjectionmoldingcondition.(1)materialproblems:Dry

4、ingmaterialAddlubricantReducethevolatilematterinthematerial(2)injectionmoldingconditionInsufficientinjection;Increasinginjectionpressure;Increaseinjectiontime;Increasethetotalpressuretime;Increasinginjectionspeed;Theincreaseoftheinjectioncycle;Thereasoncausingabnormaloperationoftheinjec

5、tioncycle.(3)temperatureproblemToomuchmaterialcausesexcessiveshrinkage;Thematerialistoocold,resultingininsufficientcompaction;Themoldtemperatureistoohighduetomoldwallmaterialcanbequicklycured;Themoldtemperatureistoolow,resultingininsufficientmoldfilling;Mouldhaspartialoverhotspot;Changi

6、ngthecoolingscheme.(4)dieproblem;Gateenlargement;Enlargedistributarychannel;Increasemainstreamroad;Increasenozzlehole;Improvedmoldexhaust;Thebalancefillingrate;Thefillingmaterialflowtoavoidinterruption;ThegatefeedingarrangementofWIPthickwallparts;Ifitispossibletoreducethewallthicknessdi

7、fference;Themoldcausedbyabnormalinjectioncycle.(5)equipmentproblem:Increasingtheplasticizingcapacityoftheinjectionpress;Maketheinjectioncyclenormal;(6)coolingconditions:Thepartsarecooledtoolonginthemoldtoavoidcontractionfromtheoutsideandshortenthecoolingtimeofthemold;Coolingthe