Enjection problems and troubleshooting (3)

Enjection problems and troubleshooting (3)

2022.10.06

Enjection problems and troubleshooting (3)

七. Weld or Meld line 結合線 A weekness or visible flaw created when two or more flow paths meet during the filling process. 在填充過程中兩條或更多流路相遇時, 因流動尖端的溫度稍微下降, 而互不熔合產生的條痕及缺陷。
Possible Cause	Correction action
Material flow too slow 原料流動性不良	1. Increase melt temperature 提高原料溫度 2. Increase back pressure to raise screw shaft speed 提高背壓加快螺桿轉速 3. Change material 更換原料
Mold temperature too low 模具溫度過低	Increase mold temperature 提高模具溫度
Injection speed too slow 射出速度太慢	Increase injection speed 增加射出速度
Injection pressure too low 射出壓力過低	Increase injection pressure 提高射出壓力
Contaminated material or mix with foreign material 原料不潔或滲有它料	Check material 檢查原料
Insufficient lubricant 潤滑劑不足	Less use Release agent 脫模油盡量少用或不用
Sprue and gate diameter too small 澆道及澆口太小	Increase lubricant 酌增潤滑劑
Air trapped in the cavity 模穴內空氣排除不及	Add vents or check if vents get clogged 增開排氣孔或檢查是否有阻塞
No overflow well 缺乏溢流井	Add overflow wells at the under end of welding line 在結合線處之下端增設溢流井

八. Flow lines 流紋 A flow pattern as linear grooves or circular ripples on the surface of the molded product which is the track of melt plastic flow within the cavity of the mold 成型品表面的直線凹槽或圓形波紋，是熔融塑料流痕在成品表面的現象
Possible Cause	Correction action
Improper material melt 原料熔融不佳	1. Increase melt temperature 提高原料溫度 2. Increase back pressure to raise screw shaft speed 提高背壓加快螺桿轉速
Mold temperature too low 模具溫度過低	Increase mold temperature 提高模具溫度
Injection speed too slow 射出速度太慢	Increase injection speed 增加射出速度
Injection pressure too low or too high 射出壓力過低或過高	Adjust injection pressure 調整適度壓力
Contaminated material or mix with foreign material 原料不潔或滲有它料	Check material 檢查原料
Gate hole diameter too small 溢口過小	Increase dimension 加大溢口
Not even thickness of product 成品斷面厚薄相差太多	Redesign product or spill hole location 變更成品設計或溢口位置

九. Silver streaks 銀紋(銀線)、氣瘡(起倉) A shining line shaped patterns appear on the surface of the molded product. 在成形品表面，順著塑膠流動的方向出現銀白色條紋的現象
Possible Cause	Correction action
Moisture in material 原料含有水份	1. Dry material 原料徹底烘乾 2. Increase back pressure 提高背壓
Material temperature too high or overheat mold to produce air 原料溫度過高或模具過熱導致氣體產生	Reduce material temperature and mold temperature 降低原料溫度及模溫
Material contains additives like lubricant, dying pigment and so on 原料中含其他添加物如潤滑劑、染料等揮發物	Reduce useage or replace high temperature plastic 減少其使用量或更換耐溫較高之替代品
Poor mix among additives 原料中其他添加物混合不均	fully mix additives 徹底混合均勻
Enjection speed too fast 射出速度太快	Slow enjection speed 減慢射出速度
Mold temperature too low 模具溫度太低	Increase mold temperature 提高模具溫度
Material pellets not uniform 原料顆粒粗細不均	Use uniform pellets 使用粒狀均勻之原料
Poor flow path in the mold 原料在模內流程不當	Adjust gate dimension and position 調整溢口之大小及位置 2. Keep mold temperature stable 模具溫度保持平均

十. Dull surface finish 成品表面不光澤 Product surface become clouded, it has low gross or Less reflection on molded surface. 產品表面變渾濁，表面有低粗反射或較少反射
Possible Cause	Correction action
Mold temperature too low 模具溫度過低	Increase mold temperature 提高模具溫度
Low filling material 原料用量不夠	1. Increase enjection volume 增加射出量 2. Extend enjection time 延長射出時間 3. Increase enjection pressure 增加射出壓力
Excessive release agent in the cavity 模內過多脫模油	Clean and dry it 擦拭乾淨
Moisture in the mold 模內壁有水	Wape and check if water leak out 擦拭並檢查是否有漏水
Rough wall of the mold 模內壁不光滑	Polish the mold 模具拋光

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