Shanghai Daoqin Plastics Co., Ltd.

injection molding process defect methods

injection molding process defect methods
injection disadvantages and phenomenon most in in injection molding products quality upper 反映出. injection molding products disadvantages can separation formed lower 列几点:
（1） product injection 不足;
（2） product 溢边;
（3） product and bubbles;
（4） product has 接痕;
（5） product 发脆;
（6） plastics color;
（7） product has silver streaks, and flow marks;
（8） product gate mixed 浊;
（9） product warpage and shrinkage;
（10） product dimensions 不准;
（11） product viscous inner;
（12） material material viscous runner;
（13） nozzle 流涎.

lower 面一一叙述 its generate causes and 克服 办 method.
⒈ how to product injection 不足
product material 不足往往 due to material material in 未充满 type front already solid 化, also has other multiple causes.
⑴ equipment causes:
① material in material;
② material shrink separation or full 部堵塞;
③ add material amount 不够;
④ add material control system as positive 常;
⑤ 注 pressure machine 塑化容 amount small;
⑥ equipment formed injection cycle 反常.
⑵ injection molding conditions causes:
① injection pressure low;
② in injection cycle in injection pressure loss large;
③ injection time short;
④ injection full pressure time short;
⑤ injection speed rate slow;
⑥ mold cavity inner material in 断;
⑦ 充模 speed rate and other;
⑧ 操 as conditions formed injection cycle 反常.
⑶ temperature degree causes:
① improve/increase material temperature degree;
② improve/increase nozzle temperature degree;
③ 检查 milli 伏计, hot electrical 偶, electrical retardant plastics raw materials material property electrical hot 圈（ or outer add hot plant/unit ） and add hot system;
④ improve/increase mold temperature;
⑤ 检查 mold temperature control plant/unit.
⑷ mold causes
① runner small;
② gate small;
③ nozzle small;
④ gate 位置不 combined 理;
⑤ gate 数不足;
⑥ cold material small;
⑦ 排 gas 不足;
⑧ mold formed injection cycle 反常;
⑸ material material causes: material material flow property 太差.

⒉ how to product flash material:
product 溢边往往 due to defect formed, other causes has: injection force large clamping force, material material temperature degree high, gas 不足, add material amount, upper has material and other.
⑴ mold issues:
① type and type 芯未闭紧;
② type and type 芯偏移;
③ 模 sheet/plate 不平行;
④ 模 sheet/plate deformation;
⑤ 模子平面落入异 material;
⑥ 排 gas 不足;
⑦ 排 gas large;
⑧ mold formed injection cycle 反常.
⑵ equipment issues:
① products 投影面积 ultra- 注 pressure machine most large injection 面积;
② 注 pressure machine sheet/plate adjustment positive 确;
③ mold 安装不 positive 确;
④ clamping force can maintain 恒定;
⑤ 注 pressure machine sheet/plate 不平行;
⑥ 拉杆 deformation 不均;
⑦ equipment formed injection cycle 反常
⑶ injection molding conditions issues :
① clamping force low
② injection pressure large;
③ injection time long;
④ injection full pressure time long;
⑤ injection speed rate fast;
⑥ 充模 speed rate and other;
⑦ mold cavity inner material in 断;
⑧ add material amount control large;
⑨ 操 as conditions formed injection cycle 反常.
⑷ temperature degree issues:
① material temperature degree high;
② nozzle temperature degree high;
③ mold temperature high.
⑸ equipment issues:
① increase large pressure machine 塑化容 amount;
② make injection cycle positive 常;
⑹ cooling conditions issues:
①部 parts in inner cooling long, 避免由 outer shrinkage, shrink short cooling time;
② will made parts in hot water in cooling.

3, how to product and gas 孔
product usually due to products upper force 不足, material material 充模不足以 and products design combined 理, 凹痕常出现 in and thin versus thick separation. gas 孔 造 formed is due to mold cavity inner plastics 不足, outer plastics cooling solid 化, internal plastics generate shrinkage formed true 空. more semi due to wet property material material drying good, and material material in mono and other combined material formed. gas formed causes, need plastics products bubbles in mold opening 时瞬时出现 also is cooling rear 出现. if mold opening 时瞬时出现, more semi is material material issues, if is cooling rear 出现 则 belongs to or injection molding conditions issues.
（1） material material issues:
① drying material material
② add lubricant
③ reduce material material in material
（2） injection molding conditions issues
① injection amount 不足;
② improve/increase injection pressure;
③ increase injection time;
④ increase full pressure time;
⑤ improve/increase injection speed degree;
⑥ increase injection cycle;
⑦操 as causes formed injection cycle 反常.
（3） temperature degree issues
① material material hot formed amount shrinkage;
② material material cold formed material pressure 实不足;
③ mold temperature high formed 模壁处 material material can very fast solid 化;
④ mold temperature low formed 充模不足;
⑤模子 has local hot 点;
⑥改变 cooling solution/scheme.
（4） mold issues;
① increase large gate;
② increase large separation runner;
③ increase large runner;
④ increase large nozzle 孔;
⑤改进模子排 gas;
⑥ balanced speed rate;
⑦避免充模 material in 断;
⑧ gate material in products thick 壁部位;
⑨ if has can can, decrease/reduce products thick 差异;
⑩模子造 formed injection cycle 反常.

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