切换手柄注射模设计

根据切换手柄的使用要求,针对以往曾出现的瑕疵,对细节进行改善。从而一次试模合格,大幅减少试模成本,提高了注射生产合格率,为以后同类结构的零件提供很好的参考价值。     

基于Pro/E软件的上壳体注射模设计方案

以壁挂空调器上壳体注射模具方案设计为例,详细地介绍了Pro/E软件中的零件模块、模具模块、装配模块等在复杂注射模具设计过程中的使用方法和程序,充分展现了动模侧一复杂斜导柱滑块组件的结构设计要点,希望能对复杂注射模具设计有一定的指导意义。     

电热咖啡壶过滤器注射模设计

根据塑件的结构特点,电热咖啡壶过滤器注射模选用1模2腔的结构形式,采用点浇口从塑件的中心部位进料,保证了塑件使用的质量要求。对塑件外圆上的槽位,模具采用了斜导柱和瓣合滑块的侧向分型抽芯机构,解决了制件成型后的脱模问题。模具安装在注射机上成型时,要保证这种带有不锈钢过滤网和铜质螺纹嵌件在模内的定位和固定,使塑件在成型后获得了良好的质量。     

蒸汽吞吐极点降维法注汽量设计

蒸汽吞吐是目前稠油油藏开发的主要方式，合理利用蒸汽热能、提高油汽比对于稠油油藏的经济有效开发非常重要。蒸汽吞吐中注汽量对周期油汽比影响巨大，但注汽量是多相关、多维空间的一个复杂组合。参考数理统计中“分类”、“聚类”及数学分析中极点降维的思路对注汽量问题进行分析，先“分”再“析”，对合理注汽量进行设计，并编制了相关软件，为稠油蒸汽吞吐中的注汽量设计提供了一种新思路。     

脉动压力诱导注塑聚丙烯-纳米CaCO_3复合材料的性能

采用电磁动态注塑成型机脉动压力诱导注塑成型聚丙烯(PP)-纳米CaCO3复合材料,通过调节加工过程中的振幅和振动频率,研究了纳米CaCO3在PP中的分散性能及由此引起PP-纳米CaCO3复合材料力学性能和结晶行为的变化,探讨了振幅和振动频率对PP-纳米CaCO3复合材料性能的影响。实验结果表明,随振幅和振动频率的增加,纳米CaCO3在PP熔体中分散得更均匀,PP-纳米CaCO3复合材料的拉伸强度和冲击强度比稳态(未施加振动)注塑试样分别提高了17.1%和14.3%,PP-纳米CaCO3复合材料的熔点升高,并对其影响机理进行了分析。     

新型轿车电动玻璃升降器箱与盖注塑模设计

新型轿车电动玻璃升降器的塑料箱与盖,是升降器传动机构的组装与支撑件。箱与盖的孔与孔位精度,决定着传动机构的性能和精度。在提供了样品的情况下,接收方提出供给方所生产的升降器要与进口产品能通用的要求。箱与盖注塑模设计的过程中,根据样品上模具结构成型痕迹和注塑件的形体分析,确定了注塑模的结构。实践证明,所加工的箱和盖与样品达到了一致,实现了与进口件混装的要求。     

继电器罩壳注塑模具设计

介绍了一款继电器罩壳的注塑模,产品形状较复杂,外观要求较高。模具采用动模三面侧向抽芯机构,脱模机构采用推杆推出,借助模流分析软件Moldflow,分析了继电器罩壳注塑成型时的最佳浇口位置,进浇点数、冷却及翘曲变形情况,确定了侧浇口的进胶位置,保证了制件成型质量,模具设计中充分利用标准件、常规件,简化了模具结构。     

山东温石塘地热田回灌补源压裂增注试验

地热田回灌补源是实现地热能资源可持续开发的新技术,用于解决地热能补给,提高地热能利用率。其方法是在距开采井一定距离,施工一眼注水井,通过注水井向地下注入一定比例的水量与热源再交换,提高热能资源量。介绍了对注水井实施压裂、增加对地热井注水量的新工艺。经水力压裂和抽水试验,增注水效果明显,为我国合理开采利用和保护地热能资源提供了一种新的技术方法。     

Large eddy simulations for radiation-spray coupling for a lean direct injector combustor

Large Eddy Simulations (LESs) for a lean-direct injection (LDI) combustor are performed and compared with experimental data. The LDI emissions characteristics, and radiation-spray coupling effect on the predictions are analyzed. The flamelet progress variable approach is employed for chemistry tabulation coupled with a stochastic secondary breakup model. Good comparisons are shown with the experimental data mean and root mean square for both the gas phase and spray droplets profiles. The effect of combustion is found to change the shape and structure of the central recirculation zone to be more compact in length but larger in diameter in the transverse direction. In-addition the results show that the gas phase radiation alters the spray dynamics by changing the local gas-phase temperature distribution. This impacts the spray evaporation rate, the local mixture fraction, and consequently the combustion heat released rate and the predicted emissions. The simulation with no radiation modeling shows over prediction in the temperature distribution, pollutants emissions, higher fuel evaporation rate, and narrower range of droplet size distribution with lower number density for the smaller size particles. The current study suggests that, even for low pressure systems, radiation modeling can be important for accurate emissions prediction.     

Crystallization behavior and molecular orientation of high density polyethylene parts prepared by gas‐assisted injection molding

The dependence of hierarchy in crystalline structures and molecular orientations of high density polyethylene parts with different molecular weights molded by gas‐assisted injection molding (GAIM) was intensively examined by scanning electron microscopy, two‐dimensional wide‐angle X‐ray scattering as well as dynamic rheological measurements. The non‐isothermal crystallization kinetics of the samples were also analyzed with a differential scanning calorimeter at various scanning rates. It was found that oriented lamellar structure, shish‐kebab and common spherulites were formed in different regions of the GAIM samples. The scanning electron microscope observations were consistent with the two‐dimensional wide‐angle X‐ray scattering results and showed that the molecular chains near the mold wall had strong orientation behavior, revealing the distribution of the shear rate of the GAIM process. The differences in crystal morphologies can be attributed to molecular weight differences as well as their responses to the external fields during the GAIM process. The formation mechanism of the shish‐kebab structure under the flow field of GAIM was also explored. Copyright © 2012 Society of Chemical Industry