迷宫型灌水器快速模具设计及加工参数优化

Rapid design of the mold and optimization of processing parameters for labyrinth channel emitter

针对迷宫型灌水器传统注塑模具加工周期长,加工成本高的问题,为适应产品快速开发的需要,该研究开发了一种灌水器模具的快速制造技术和注塑成型工艺。利用数字ABS作为模具材料,采用聚合物喷射技术成型模具确保精度和强度。为确定不同加工参数对成型质量的影响,以翘曲变形量和缩痕估算为分析指标,通过Moldflow软件进行了单因素试验和四因素五水平的正交试验。建立了翘曲变形和缩痕估算与各参数间的回归模型,并通过粒子群算法得到了最优工艺参数。试验结果表明,冷却时间对翘曲变形量和缩痕无影响,熔体温度、保压压力和保压时间对翘曲变形和缩痕产生决定性的影响,最佳工艺参数组合为熔体温度230℃,保压压力3 MPa,保压时间4 s。优化成型工艺参数后,翘曲变形下降8.72%,缩痕估算下降20.68%,熔接痕减少,塑件质量得到提高,达到设计要求。在注塑机中使用快速模具进行了注塑试验验证,证明了结构和工艺的正确性。相较于传统模具加工,快速模具实现了灌水器快速开发,在保证灌水器质量的情况下大幅度缩短了加工时间,降低了加工成本,该研究可为新型灌水器的设计与开发提供一定的理论基础。

Traditional mold development process is long and costly,to solve the problems of long processing cycles and high processing cost of traditional injection irrigation molds of the labyrinth channel emitter,a rapid manufacturing technology and injection molding process of the emitter mold was developed in this study.Digital ABS was used as the rapid mold material and PolyJet technology was chosen to form the mold to ensure accuracy and strength.The mechanical properties and thermodynamic properties of rapid molds were different from that of ordinary molds.The thermal conductivity of digital ABS as a mold material was about one thousandth of traditional mold steel,which indicated that the processing parameters affected product quality were also quite different from ordinary molds.In order to determine the influence of different processing parameters on the forming quality,the warpage amount and shrink mark were used as the evaluation index.The initial molding process parameters were mold surface temperature 52℃,melt temperature 230℃,filling control was automatic,speed/pressure was switched to automatic,holding pressure was 2MPa,holding time was 3 s,and cooling time was 30 s.The single-factor experiments,and the four-factor five-level orthogonal experiments were conducted through Moldflow software.The regression models between warpage deformation amount and shrink mark with different parameters were obtained.The experimental results showed that the cooling time had no effect on the amount of warpage and shrinkage,and the melt temperature,holding pressure and holding time had a decisive effect on warpage and shrinkage.Before parameter optimization,the shrink mark under the initial processing parameters was estimated to be 0.19 mm,and the maximum warpage deformation was 0.54 mm.The best process parameters obtained by Moldflow were melt temperature 230℃,holding pressure 3 MPa,holding time 4 s.After optimizing the molding process parameters,the warpage deformation and the shrink mark were reduced by 20.68%and 8.72%respectively.The weld marks were reduced,the quality of plastic parts was improved,and the design requirements were met.In the injection molding machine,a rapid mold was used to verify the injection molding experiment,which proved the correctness of the structure and process.The size of the produced irrigator was 41.28 mm×9.322 mm×2.820 mm,and the product design size was 42.0 mm×9.5 mm×3.0 mm.The deviations from the design values were 1.71%,1.87%and 6%respectively,and the accuracy was remarkably high.Regarding the size of the flow channel,the relative error between the processing size and the design size of the flow channel of the labyrinth channel emitter was 9.3%,and the dimensional accuracy met the requirements.Compared with the traditional mold processing,the rapid mold realized the rapid development of the irrigation device.Under the condition of ensuring the quality of the irrigation device,the processing time was greatly shortened and the processing cost was reduced.Rapid mold technology shortened the original mold processing time of about 20 days to 2 days.It provided a certain theoretical basis for the design and development of new irrigation devices.