Research on On-line Quality Monitoring Method for Injection Molding Products of Crystalline Plastic

doi:10.3969/j.issn.1004-132X.2022.09.008

Abstract

Abstract: For crystalline materials, the quality of plastic products was closely related to crystallinity. An on-line monitoring of product quality was realized by measuring the crystallinity of plastic products according to the physical characteristics of capacitive sensors. The influence mechanism of melt temperature, injection pressure, injection time and holding pressure on crystallinity was studied. At the same time, the relationships of crystallinity-processing parameters-mechanics properties were analyzed. A set of injection mold was designed and manufactured for experimental verification. Results show that the tensile strength and bending strength of the injection parts increase with the increase of crystallinity, and the crystallinity of the products may be controlled effectively by adjusting the processing parameters, and then the injection products with excellent mechanics properties may be obtained.

Key words: on-line monitoring, injection molding, crystallinity, processing parameter, quality of product

摘要： 结晶性材料的结晶度与塑料制品质量有紧密联系。利用电容传感器的物理特性，通过测量注塑成形过程中的结晶度来实现制品质量的在线监测，重点研究了熔体温度、注塑压力、注塑时间及保压压力对结晶度的影响机制，同时分析了工艺参数-结晶度-力学性能的关系，设计并制造出了一套注塑模具进行试验验证。试验结果表明，随着结晶度的增大，注塑件的拉伸强度和弯曲强度随之增大，通过调控工艺参数，能有效控制制品的结晶度，进而得到优良力学性能的注塑制品。

关键词: 在线监测, 注塑成形, 结晶度, 工艺参数, 制品质量

CLC Number:

TB332

QIAN Yingping, XUE Hang, MEI Jianliang. Research on On-line Quality Monitoring Method for Injection Molding Products of Crystalline Plastic[J]. China Mechanical Engineering, 2022, 33(09): 1073-1076,1083.

钱应平, 薛杭, 梅建良. 结晶性塑料制品注塑成形质量在线监测方法研究[J]. 中国机械工程, 2022, 33(09): 1073-1076,1083.

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