摘要
为了克服常规脱模方式下注塑件易出现表面质量低、翘曲等缺陷,提出利用透气钢实现注塑件脱模的新方法。该方法将透气钢作为气动脱模介质,使气体通过其微孔直接到达制品的底部,由于气体的等压性,可确保脱模时注塑件受到均匀的顶出力,不发生传统脱模机构中引起的翘曲变形现象。为了确定脱模过程中透气钢的工作参数,采用定压差测流量的方法实验研究考虑气体可压缩性时透气钢的透过性能。研究结果表明:随着压力的增大,气体在透气钢中将发生从Darcy流动到非Darcy流动的转变,分别对这2种流动状态的透过系数和惯性系数进行分析计算,得出了这两种状态的流动方程,揭示该流体流动状态下透气钢中气体的流动规律,为这种新脱模方法的使用提供数据和理论支持。
An innovative permeable steel based demolding method was proposed in order to reduce demolding-caused defects in conventional injection molding.The proposed method utilized permeable steel,which allowed air to pass through its micro-pores and exerted an evenly distributed demolding force on the bottom of molded part,thus ensuring elimination of part warpage in conventional demolding mechanism.Working parameters of permeable steel were determined by experimental study of its permeability in which air flow was measured with constant pressure difference considering air compressibility.The results show that air flow in permeable steel shifts from Darcy flow to non-Darcy flow when pressure difference increases.Permeability coefficient and inertia coefficient under both flow conditions were analyzed and calculated.The flow equations are obtained,and the air flow behavior in permeable steel is revealed.The study presented in this work collects essential data and establishes basic theory for the application of the proposed new demolding method.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第9期2663-2668,共6页
Journal of Central South University:Science and Technology
基金
国家高技术研究发展计划("863"计划)项目(2007AA04Z351)
关键词
微注射成型
气动脱模系统
透气钢
透过性能
micro-injection molding
pneumatic demolding system
permeable steel
permeability
