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成型過程問題

產生原因 及解決辦法

1、銀絲

a、原材料受潮----干燥原料

b、樹脂過熱分解----減低成型溫度

c、螺桿壓縮比小，背壓不足----增加背壓

d、模溫過低----加熱模具

e、排氣不良----模具分型面開排氣槽

2、氣泡

a、原材料受潮----干燥原料

b、排氣不良----改進模具設計

3、樹脂變色、黑點

a、料筒、噴嘴積料----清理料筒和噴嘴

b、成型溫度過高----降低成型溫度

4、制品未充滿

a、物料塑化不夠----提高料筒溫度

b、模具溫度過低----提高模具溫度

c、噴嘴溢料----調整模具位置

d、注射壓力過低----提高注射壓力

e、加料量過少----調整加料量

5、收縮真空泡

a、保壓不足----延長保壓時間

b、模溫過低----提高模具溫度

c、注射壓力過低----提高注射壓力

d、模具設計不合理----增加流道和澆口尺寸

e、成型溫度較低----提高料筒溫度

6、透明度降低

a、原材料受潮----干燥原料

b、模具溫度過低----提高模具溫度

c、物料過熱分解----降低成型溫度

7、熔接痕

a、模具設計不合理----采用環形澆口和多點澆口

b、模具溫度過低----提高模具溫度

c、脫模劑過多----減少脫模劑用量

d、成型溫度較低----提高料筒溫度

8、制品開裂

a、模溫過低----提高模具溫度

b、成型溫度較低----提高料筒溫度

c、物料的相對分子量過小----重新選擇物料

d、成型過程中相對分子量下降過多----嚴格干燥，縮短成型周期

e、強行脫模----加大型腔斜度，改進模具結構

9、脫模困難

a、模內冷卻不充分----降低成型溫度，延長成型周期

b、型腔斜度酞小----增加型腔斜度

c、頂出裝置不良----改進頂出裝置

d、模具表面粗糙----修整模具，使用脫模劑

10、翹曲

a、模內冷卻不充分----降低成型溫度，延長成型周期

b、凸模、凹模溫差較大----減少凸模、凹模溫差

c、澆口位置和尺寸不合理----改進澆口結構

11、溢邊

a、注射壓力過大----降低注射壓力

b、成型溫度過高----降低料筒溫度

c、鎖模力不足----提高鎖模力

d、模具加工精度不足----提高模具加工精度

Safety controversy because of the need to add bisphenol a to the manufacture of polycarbonate, and Bisphenol a as a chemical raw material, on April 18,2008, has been officially recognized by the Federal Government of Canada as a toxic substance, and prohibited in food packaging, therefore, the safety of polycarbonate is worth paying attention to. Baby bottles that contain the chemical bisphenol a (BPA) have been banned from March 2,2011, as the European Union considers them to cause premature puberty. The import and sale of polycarbonate and other BPA containing baby bottles will be banned from 1 September 2011 and recalled by manufacturers or importers, the Ministry of Health of the People's Republic of China and other agencies said in a statement. Packaging transport polycarbonate (PC) products are generally used in ordinary packaging, stored in a dry place, according to the general goods storage and transportation. Storage and transportation conditions sealed, cool, ventilated dry place, and flat storage. IMD/IML process-specific low-temperature plastic injection molding PC mainly solves the following problems: 1, Chong Mo 2, poor liquidity 3, product yellowing 4, with sheet miscibility and other related problems low-temperature plastic injection PC product characteristics: 1, product ultra-high toughness 2, product high transparency 3, ultra-high fluidity 4, good chemical resistance 5, good compatibility with sheet injection temperature: low-temperature injection PC plastic a injection temperature 220 to 240; Low temperature injection PC plastics class B injection temperature 230 to 260.