Shanghai Daoqin Plastics Co., Ltd.

        一. injection molding products cracking causes analysis

         cracking, made parts surface filament cracks, micro 裂, 顶白, cracking and made parts mold sticking, runner mold sticking formed or 创伤危 machine, cracking time separation demolding cracking and application cracking. main/primary has below/following several causes formed:

        1. processing 方面:

        (1) processing pressure large, speed degree fast, material more, injection, holding pressure time long, 都会造 formed internal stress large cracking.

        (2) adjustment mold opening speed degree and pressure anti fast speed strong/high made parts formed demolding cracking.

        (3)适当调 high mold temperature degree, make made parts easy demolding, 适当调 low material temperature anti separation understanding.

        (4)预 anti due to 熔接痕, plastics degradation formed machine strong/high degree low 而出现 cracking.

        (5)适当 use demolding agent, attention/notes 经常消 remove 模面附 gas and other material 质.

        (6) made parts residual stress, can through in molding rear 立即进行退火 hot 处理 消 remove internal stress decrease/reduce cracks formed.

        2. mold 方面:

        (1) ejection need balanced, 如顶杆数 amount, 截面积 need 足够, demolding degree need 足够, type need has light slip, this anti due to outer force ejection residual stress in cracking.

        (2) made parts structure can thin, 渡部份应尽 amount using/adopting 圆弧 渡, 避免尖角, 倒角造 formed force in.

        (3)尽 amount less use metal parts, anti parts and made parts shrinkage rate different formed internal stress add large.

        (4) for deep made parts 应设置适当 demolding gas 孔道, anti formed true negative pressure.

        (5)主 runner large make gate material future and solid demolding, this easy demolding.

        (6)主 runner sleeve/set and nozzle combined anti cold hard material 拖拉而 make made parts viscous in upper.

        3.材 material 方面:

        (1) recycled material content high, formed made parts strong/high degree low.

        (2) wet degree large, formed plastics and water 汽发生 chemical reaction, reduce strong/high degree 而出现 ejection cracking.

        (3)材 material 本身不适宜 positive in processing ring or quality 欠佳, to 污染都会造 formed cracking.

        4. machine 台方面:

         injection molding machine 塑化容 amount need 适当, small 塑化不充 separation can full mixed combined 而变脆, large degradation.

        二. injection molding products bubbles causes analysis

         bubbles (true 空泡) gas separation dilute thin belongs to true 空泡. generally 说, if in mold opening already 发现存 in bubbles is belongs to gas dry issues. true 空泡 形 formed is due to 充注进 plastics or pressure relatively low. in mold cooling function lower, and type 腔接角 燃 material 牵拉, formed loss 失 结果.

         solutions:

        (1) improve/increase injection can amount: pressure, speed degree, time and material amount, improve/increase back pressure, make 充模丰满.

        (2) increase material temperature flow 顺畅. reduce material temperature decrease/reduce shrinkage, improve/increase mold temperature, especially is formed true 空泡部位 local mold temperature.

        (3) will gate in made parts thick 部份, improvement nozzle, runner and gate flow 状况, decrease/reduce pressure 务 消 consumption.

        (4)改进 mold gas 状况.

        三. injection molding products warpage deformation causes analysis

         injection molding products deformation, bending, phenomenon main/primary is due to plastics molding flow direction shrinkage rate ratio direction large, make made parts toward shrinkage rate different warpage, also due to injection 充模时不 can in made parts internal has relatively large internal stress 而引起 warpage, this is high force orientation formed deformation performance. therefore from upper 说, mold design made parts warpage toward, need through more molding conditions made this type of toward is separation difficult, most solution issues must from mold design and 改良 手. this type of phenomenon main/primary has below/following several 方面造 formed:

        1. mold 方面:

        (1) made parts thick degree, quality need uniform.

        (2) cooling system design need make mold type 腔各部 separation temperature degree uniform, system need make material for 称避免因 flow direction, shrinkage rate different formed warpage, add coarse relatively difficult molding separation runner, runner, amount remove type inner density 差, pressure 差, temperature degree 差.

        (3) made parts thick thin and need 足够圆 slip, need has good demolding property, increase demolding degree, improvement 模面 抛 light, ejection system need unchanged 衡.

        (4)排 gas need good.

        (5) increase made parts thick or increase resistant warpage direction, add strong/high reinforcement made parts resistant warpage can force.

        (6) mold use material strong/high degree 不足.

        2. plastics 方面:

         crystallization type ratio non crystallization type plastics warpage deformation machine more, add crystallization type plastics can utilizing crystallization degree cooling speed degree increase large reduce, shrinkage rate small crystallization process positive warpage deformation.

        3. processing 方面:

        (1) injection pressure high, holding pressure time long, material temperature degree low speed degree fast formed internal stress increase 而出现 warpage deformation.

        (2) mold temperature degree high, cooling time short, make demolding made parts hot 而出现 ejection deformation.

        (3) in maintain most low degree material amount lower decrease/reduce screw speed and back pressure reduce density made internal stress generate.

        (4) necessary can for easy warpage deformation made parts mold soft property or demolding rear 进行退米处理.

        四. injection molding products color strip/profile color color analysis

         this type of defect main/primary is using/adopting color masterbatch color plastics made parts relatively 常出现 issues, although color masterbatch color in color type stability property, color pure degree and color property and other 方面均 excellent dry powder color, color, separation property, color in dilute plastics in mixed combined uniform degree versus for relatively 差, made formed product 自然就 belt/tape has property color 泽差异.

         main/primary solutions:

        (1) improve/increase add material temperature degree, especially is add material rear temperature degree, make its temperature degree or high melt temperature degree, make color masterbatch 进入熔 melt 段时尽 fast 熔化, promote and dilute uniform mixed combined, increase liquid mixed combined machine 会.

        (2) in screw speed 一定 情况 lower, increase back pressure pressure make material inner material temperature degree, function to improve/increase.

        (3)修改 mold, especially system, gate wide, melt material through 时, 紊流效果差, temperature degree improves high, is non-uniform, color belt/tape mold cavity, 应予改 narrow.

        五. injection molding products shrinkage causes analysis

         injection molding process in, products shrinkage is comparison Common phenomenon. formed this type of main/primary causes has:

        1. machine 台方面:

        (1)射嘴孔太 large formed melt material 回流而出现 shrinkage, small retardant force large material amount 不足出现 shrinkage.

        (2) clamping force 不足造 formed flash 也会出现 shrinkage, 应检查锁模 system is has issues.

        (3)塑化 amount 不足应 selection amount large machine 台, screw and material is abrasion loss.

        2. mold 方面:

        (1) made parts design need make thick uniform, ensure shrinkage 一致.

        (2) mold cooling, add temperature system need ensure 各部份 temperature degree 一致.

        (3)浇注 system need ensure 通畅, retardant force can large, runner, separation runner, gate dimensions need 适当, light degree need 足够, need 圆弧 渡.

        (4) for thin parts improve/increase temperature degree, ensure material 流畅顺, for thick made parts reduce mold temperature.

        (5) gate need for 称开设, amount in made parts thick 壁部位, increase cold material 井容积

        3. plastics 方面:

         crystallization property plastics ratio non crystallization property plastics shrinkage 历害, processing need increase material amount, or in plastics in add formed agent, add fast crystallization, decrease/reduce shrinkage 凹陷.

        4. processing 方面:

        (1) material temperature degree high, 容积变化 large, especially is front temperature degree, for flow property plastics 应适当 improve/increase temperature degree, ensure 畅顺.

        (2) injection pressure, speed degree, back pressure low, injection time short, make material amount or density 不足而 shrinkage pressure, speed degree, back pressure large, time long formed flash 而出现 shrinkage.

        (3) add material amount 即缓冲垫 large consumption injection pressure, small 时, material amount 不足.

        (4) for/regarding requirements degree made parts, in injection holding pressure 完毕, outer basic cold hard 化而夹心部份尚 soft/flexible also can ejection made parts, and 早出模, let its in gas or hot water in slow cooling, can make shrinkage 凹陷平缓而不 that 么显眼 also effect/influence use.

        六. injection molding products transparent defect causes analysis

        熔斑, 银纹, cracks polystyrene (PS), has machine transparent made parts, has 时候透 light can to 一 闪闪发 light fine filament 般 银纹. this also 称烁斑 or cracks. this is due to force direction generate force, use polymer separation heavy type flow orientation and orientation separation rate performance 出.

         solution methods:

        (1)消 remove gas and its it dry 扰, for plastics separation drying.

        (2) reduce material temperature, separation adjustment material temperature degree, improve/increase mold temperature.

        (3) increase injection pressure, reduce injection speed degree.

        (4) increase or decrease/reduce back pressure pressure, decrease/reduce screw speed.

        (5) improvement runner and type gas 状况.

        (6)清理射嘴, runner and gate can can 堵塞.

        (7) shrink short molding cycle, demolding rear can use methods remove 银纹: for polystyrene (PS) in 78℃时 maintain 15 separation 钟, or 50℃时 maintain 1 small 时, for polycarbonate (PC), add hot to 160℃ above maintain separation 钟.

        七. injection molding products color causes analysis

        造 formed injection molding products color main/primary causes and solution methods lower:

        (1) color agent expand dispersion defect, this type of 情况往往 make gate 附近出现花纹.

        (2) plastics or color agent heat stabilized property 差, need stability made parts color 调, need solid production conditions, especially is material temperature, material amount and production cycle.

        (3) for crystallization type plastics, amount make made parts separation cooling speed degree 一致, for/regarding thick large made parts, can use color agent Color Difference, for/regarding thick relatively uniform made parts need solid good material temperature and mold temperature.

        (4) made parts type and gate 形式, for plastics 充填情况 has effect/influence, make made parts certain local generate Color Difference, necessary need 进行修改.

        八. injection molding products color and gloss defect causes analysis

         positive 常情况 lower, injection molding made parts surface tool has gloss main/primary plastics type type, color agent and light degree 决定. 但经常也会因 is other causes formed products surface color and gloss defect, surface dark color and other defect. formed this type of causes and solution methods analysis lower:

        (1) mold light degree 差, type surface has and other, mold gas defect.

        (2) mold system has defect, increase large cold material 井, increase large runner, light runner, separation runner and gate.

        (3) material temperature and mold temperature low, necessary can use gate local add hot method.

        (4) processing pressure low, speed degree slow, injection time 不足, back pressure 不足, formed property make surface dark color.

        (5) plastics need separation 塑化, need anti material degradation, hot need stability, cooling need separation, especially is thick 壁.

        (6) anti cold material made parts, necessary use 自锁式 elastic or reduce nozzle temperature degree.

        (7) use recycled material more, plastics or color agent quality 差, mixed has water or its it 杂质, use lubricant quality 差.

        (8) clamping force need 足够.

        九. injection molding products causes analysis

         injection molding products 银纹, surface bubbles and internal gas 孔. formed defect main/primary causes is gas 体(main/primary has water 汽, separation understanding gas, solvent agent gas, gas) dry 扰. specific causes analysis lower:

         machine 台方面:

        (1) material 筒, screw abrasion loss or 胶头, 胶圈存 in material 流死角, long hot separation understanding.

        (2) add hot system 失控, formed temperature degree high separation understanding, 应检查 hot electrical 偶, hot and other add hot parts is has issues. screw design 不当, formed understanding or easy belt/tape gas.

        2. mold 方面:

        (1)排 gas defect.

        (2) mold in runner, gate, type abrasion scratch retardant force large, formed local hot 而出现 separation understanding.

        (3) gate, type distribution balanced, cooling system combined 理都会造 formed hot balanced 而出现 local hot or retardant gas 通道.

        (4) cooling 通路漏 water type 腔.

        3. plastics 方面:

        (1) plastics wet degree large, add recycled material ratio/proportion more or has has property material (屑 material easy separation understanding), separation drying plastics and remove material.

        (2) from large gas in or from color agent 吸潮, for color agent 也进行 drying, most good in machine upper drying device.

        (3) plastics in add lubricant, stabilizer and other use amount more or mixed combined 不均, or plastics belt/tape has property solvent agent. mixed combined plastics hot degree difficult 以兼顾时也会出现 separation understanding.

        (4) plastics 受污染, mixed has its it plastics.

        4. processing 方面:

        (1)设置 temperature degree, pressure, speed degree, back pressure, 熔胶马达转 speed high formed separation understanding, or pressure, speed degree low, injection time, holding pressure separation, back pressure low 时, due to can obtain high pressure density 不足无 method understanding gas 体而出现银纹, 应设置适当 temperature degree, pressure, speed degree and time and using/adopting more injection speed degree

        (2) back pressure low, speed fast easy make gas material 筒, material mold, cycle long melt material in material inner hot long 而出现 separation understanding.

        (3) material amount 不足, add material 缓冲垫 large, material temperature low or mold temperature low effect/influence material flow and molding pressure, make bubbles formed.

        十. products has 熔接缝 causes analysis

        熔 melt plastics in type in due to to parts 孔洞, speed 不连贯 区域, material in 断 区域而以 more 股形式汇 combined 时, can full combined generate property 熔接缝. in addition in gate 喷射充模也会生 formed 熔接缝, 熔接缝处 strong/high degree and other property can very 差. main/primary causes analysis lower:

        1. processing 方面:

        (1) injection pressure, speed degree low, material temperature degree, mold temperature low, formed mold melt material cooling 而出现熔接缝.

        (2) injection pressure, speed degree high 时, 会出现喷射而出现熔接缝.

        (3)应 increase speed, increase back pressure pressure make plastics viscosity decline, density increase.

        (4) plastics need drying good, recycled material less use, demolding agent use amount more or quality good 也会出现熔接缝.

        (5) reduce clamping force, 方便排 gas.

        2. mold 方面:

        (1)同一 type gate more, decrease/reduce gate or for 称设置, or amount 靠近熔接缝设置.

        (2)熔接缝处排 gas defect, 应开设排 gas system.

        (3)浇道 large, system dimensions 不当, gate 开设尽 amount melt in parts 孔洞周围 flow, or amount less use parts.

        (4)壁 thick large, or thick thin, make made parts thick uniform.

        (5) necessary in 熔接缝处开设熔 combined make 熔接缝脱离 made parts.

        3. plastics 方面:

        (1) for flow property or hot property plastics 应适当添 add lubricant and stabilizer.

        (2) plastics 含 杂质 more, necessary need quality good plastics.

        十一. injection molding products causes analysis

        PS and other rigid property plastics made parts in its gate surface, gate is in 心 形 formed 密集 波纹, has is 震纹. generate causes is melt viscosity large 而以滞流形式充模时, front material 一接触 to type surface very fast cold shrinkage 起, rear material also already shrinkage cold material front process 不断交替 make material in front in formed surface 震纹.

         solution methods:

        (1) improve/increase material temperature degree especially is temperature degree, also improve/increase mold temperature degree.

        (2) improve/increase injection pressure and speed degree, make its fast speed type 腔.

        (3) improvement runner, gate dimensions, anti retardant force large.

        (4) mold gas need good, need 设置足够 large cold material 井.

        (5) made parts need design thin.

        十二. injection molding products and causes analysis

         has plastics made parts in molding demolding rear, very fast in metal parts or in especially thick 部位出现肿胀 or 鼓泡. this is is full cooling hard plastics in inner pressure function lower gas 体膨胀造 formed.

         solution measures:

        1. has cooling. reduce mold temperature, long mold opening time, reduce material drying and processing temperature degree.

        2. reduce speed degree, decrease/reduce formed cycle, decrease/reduce flow retardant force.

        3. improve/increase holding pressure pressure and time.

        4. improvement made parts 壁面太 thick or thick thin large 状况.