共查询到18条相似文献,搜索用时 78 毫秒
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在电热快速变模温注塑成型中,加热系统的优劣直接影响产品质量。而加热后模具温度的均匀性是衡量加热系统的主要指标之一,它主要与模具结构、加热棒的热流密度有关。在不改变模具结构情况下,仅通过改变各加热棒的热流密度值来提高加热后模具温度的均匀性进而达到优化加热系统的效果。首先建立了电热快速变模温注塑加热阶段的分析模型,对比了相同工艺条件下的实验结果,验证了模拟的正确性。当初始加热棒热流密度相同时,通过提高边缘加热棒的热流密度,改善了模具温度的均匀性。最后假设加热棒热流密度分别呈一次和二次函数分布,模拟分析得到当各加热棒热流密度不均匀时,为保证加热后模具温度均匀的各加热棒热流密度的取值准则。 相似文献
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介绍双色高光注塑技术的特点,通过比较双色高光注射成型与单色高光注塑成型、普通注射成型,深入分析了双色高光注塑成型塑件结构与黏合设计及模具结构设计要点。阐述了国内外双色高光注塑技术的应用现状及发展。讨论并指出了将双色高光注塑成型技术进一步推广有待解决的关键技术问题。 相似文献
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注塑充模模具温度场的数值模拟 总被引:1,自引:0,他引:1
本文运用有限元法,对注塑模具三维非稳态温度场进行了计算机辅助的数值模拟求解。以曲边六面体二十节点等参数有限单元,推导了有限元数值求解方程并研制了计算机模拟软件。实例计算结果,验证了数值求解的可靠性。 相似文献
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RHCM成型制品高光面形成微观机理研究 总被引:3,自引:0,他引:3
根据快速冷热成型技术(RHCM)成型塑料熔体在型腔内的填充流动规律,在普通注射成型机理研究基础上,从微观角度对RHCM技术在提高制品对模具的复原性,消除熔接痕、凹痕、银丝纹、流纹、表面浮纤等表观缺陷以及改善制品表面色差等方面的成型机理进行研究。结果表明,正是由于RHCM高温快速成型这一工艺特点,一方面确保熔体在型腔内的充分扩展与汇合,另一方面最大程度的限制制品的成型收缩,从而确保制件的最终成型品质。 相似文献
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A new electric‐heating rapid thermal response (RTR) mold with floating cavity/core for rapid heat cycle molding is investigated in this study. Process principles of Rapid heat cycle molding (RHCM) with such new electric‐heating mold are discussed and presented. Response surface methodology (RSM) is employed to develop mathematical relationships between layout of the heating elements and heating efficiency, temperature uniformity and structural strength of the floating cavity. Three explanatory variables including half distance between two adjacent heating rods, spacing between heating rods and cavity surface, and the diameter of the heating rod are used to describe the layout and scale of the heating elements. The response variables involving required heating time, maximum cavity surface temperature, and maximum von‐Mises stress are used to characterize heating efficiency, temperature uniformity, and structural strength of the floating cavity, respectively. Central composite design (CCD) method is used for factorial experiments. Finite element analyses are conducted for combination of explanatory parameters to acquire the corresponding values of the response variables. Three predictive models for the response variables are created by regression analysis. Analysis of variance (ANOVA) is used to check their accuracy. These response surface models are interfaced with an effective particle swarm algorithm for the optimum heating system design of the electric‐heating RTR mold. The developed optimum method is then used for the design of the floating electric‐heating cavity for an actual industrial product. The following heat transfer analysis results show that the temperature distribution uniformity of the cavity surface is greatly improved with the optimal cavity structure and layout of heating rods. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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对蒸汽模技术的基本原理、应用设备及关键技术进行了分析,阐明了模具温度控制对蒸汽模技术的重要影响,同时分析比较了蒸汽模技术与普通注塑模技术的特点与优势.最后,对蒸汽模技术的发展前景进行了展望. 相似文献
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提出一种完全基于温度的燃料燃烧热的热效率在线估计方法,解决了热效率实时测量无法长期稳定运行的难题。系统计算准确、稳定可靠、可长期运行,为热效率控制提供了真正可行的实施基础。 相似文献