智能注射成形中工艺参数的多目标自学习优化

注射成形工艺参数是保障产品质量的关键因素。传统试错法严重依赖工艺人员的试模经验,随着注射成形工艺广泛应用于电子、航空航天等国家战略领域,产品的高端化对工艺参数智能化设置水平提出更高的要求。由于成形产品存在多方面的质量要求,且不同质量指标间可能相互制约,因此亟需一种工艺参数多目标智能优化方法,以获得不同优化目标间的帕累托最优。已有学者利用智能优化方法,如非支配排序遗传算法等,对多目标优化问题进行求解,但是此类方法需大量样本数据对质量-参数关系进行建模,存在试验次数多、且对不同材料及模具的适应性较差等问题。为解决上述问题,提出一种注射成形工艺参数多目标自学习优化方法,在优化过程中实时计算并更新各个工艺参数的梯度,并由不同质量指标的多梯度下降算法对多个目标函数进行优化,在优化过程中实现各工艺参数对产品质量影响程度的自主学习,省去了采集大量数据来建立多个质量模型的过程,实现了注射成形工艺参数的高效智能优化。在基准测试函数实验中,所提方法的优化结果与理论解的相对误差小于2%。同时数值仿真与注射成形实验结果表明,所提方法能高效获得多个优化目标的帕累托最优。     

Multiobjective optimization of injection molding parameters based on soft computing and variable complexity method

The objective of this study is to propose an intelligent methodology for efficiently optimizing the injection molding parameters when multiple constraints and multiple objectives are involved. Multiple objective functions reflecting the product quality, manufacturing cost and molding efficiency were constructed for the optimization model of injection molding parameters while multiple constraint functions reflecting the requirements of clients and the restrictions in the capacity of injection molding machines were established as well. A novel methodology integrating variable complexity methods (VCMs), constrained non-dominated sorted genetic algorithm (CNSGA), back propagation neural networks (BPNNs) and Moldflow analyses was put forward to locate the Pareto optimal solutions to the constrained multiobjective optimization problem. The VCMs enabled both the knowledge-based simplification of the optimization model and the variable-precision flow analyses of different injection molding parameter schemes. The Moldflow analyses were applied to collect the precise sample data for developing BPNNs and to fine-tune the Pareto-optimal solutions after the CNSGA-based optimization while the approximate BPNNs were utilized to efficiently compute the fitness of every individual during the evolution of CNSGA. The case study of optimizing the mold and process parameters for manufacturing mice with a compound-cavity mold demonstrated the feasibility and intelligence of proposed methodology.     

塑料注射模具的并行设计方法

塑料制品注射成型属于一次成型工艺 ,传统的串行模具设计和制造方式 ,造成了对设计经验的过分依赖和模具返修率的提高 ,本文举例介绍了基于流动模拟技术的注射模并行设计方法 ,说明了 CAE对模具结构设计和相关注塑工艺的指导作用。     

注射成型工艺参数设置在线仿真程序设计

注射成型工艺参数设置对塑料制品性能的影响至关重要,但在传统的教学过程中往往侧重于基本概念的理解。文中结合Flash脚本语言设计注射成型工艺参数在线仿真程序,供学生进行在线仿真练习。     

Optimal injection molding conditions considering the core shift for a plastic battery case with thin and deep walls

The objective of this paper is to examine the influence of injection molding parameters on the core shift to obtain the optimal injection molding conditions of a plastic battery case with thin and deep walls using numerical analyses and experiments. Unlike conventional injection molding analysis, the flexible parts of the mold were represented by 3-D tetrahedron meshes to consider the core shift in the numerical analysis. The design of experiments (DOE) was used to estimate the proper molding conditions that minimize the core shift and a dominant parameter. The results of the DOE showed that the dominant parameter is the injection pressure, and the core shift decreases when the injection pressure decreases. In addition, it was shown that the initial mold temperature and the injection time hardly affect the core shift. The results of the experiments showed that products without warpage are manufactured when the injection pressure is nearly 32 MPa. Comparing the results of the analyses with those of the experiments, optimal injection molding conditions were determined. In addition, it was shown that the core shift should be considered to simulate the injection molding process of a plastic battery case with thin and deep walls.     

[成形过程的数据挖掘与深度学习方法]塑料注射成形智能技术及其应用

总结了当前塑料注射成形的产业需求和技术瓶颈，阐明了未来的发展趋势。根据塑料注射成形特性，提出“注射成形智能制造体系”的科学框架，建立以传感技术、工业以太网及互联网为基础的智能注射成形解决方案。围绕智能设计、智能优化、智能监控及制造数据平台四个层面，总结了注射成形中知识的组织与重用、自主决策与优化、过程感知与检测及云服务等技术，为实现塑料注射成形与新一代人工智能技术的深度融合指出了重要发展方向。     

气辅注气控制系统中的多模态智能PID调节器

气体辅助注射成型机的注气控制系统是一小延迟、小惯性系统。为使之能满足气体辅助注射成型工艺对气体压力的高精度控制要求，设计了一种多模态智能PID调节器。该调节器将PID控制方法和智能控制技术相结合，采用了改良型的位置式PID控制算法和归一参数在线自整定方法对控制规律和参数进行实时修正。实验证明，该PID调节器具有波动小、超调小、对环境及控制参数不敏感等优点。     

A study of optimization of injection molding process parameters for SGF and PTFE reinforced PC composites using neural network and response surface methodology

This study analyzed variations of mechanical characteristics that depend on the injection molding techniques during the blending of short glass fiber and polytetrafluoroethylene reinforced polycarbonate composites. A hybrid method including back-propagation neural network (BPNN), genetic algorithm (GA), and response surface methodology (RSM) are proposed to determine an optimal parameter setting of the injection molding process. The specimens are prepared under different injection molding processing conditions based on a Taguchi orthogonal array table. The results of 18 experimental runs were utilized to train the BPNN predicting ultimate strength, flexural strength, and impact resistance. Simultaneously, the RSM and GA approaches were individually applied to search for an optimal setting. In addition, the analysis of variance was implemented to identify significant factors for the injection molding process parameters and the result of BPNN integrating GA was also compared with RSM approach. The results show that the RSM and BPNN/GA methods are both effective tools for the optimization of injection molding process parameters.     

纸浆模塑制品生产线的设计

纸浆模塑制品具有与被包装物相吻合的几何形状和良好的防震、防冲击、防碎、防腐等理想的保护效果。它是以废纸和纸制品厂的边角余料为原料经过碎浆、调制配成一定浓度的浆料、在特制的模具上经真空吸塑而成型,再经过加热干燥而制成的。本文着重介绍了该生产线的设计指导思想、生产工艺、主要设备及成型机的结构和参数设计。     

基于Mold Flow的汽车保险丝盒壳体的结构设计

采用Mold Flow对汽车保险丝盒壳体进行填充、保压、冷却、翘曲仿真分析,获得了最佳浇口位置、最佳流动模式和最小的翘曲变形。优化了产品结构,并给出合理的注塑工艺参数,缩短了产品开发周期,降低了开发风险,提高了产品的可靠性,从而达到了降低开发成本,提高产品竞争力的目的。     

滑雪板底板注射模设计

介绍在卧式注射机上生产滑雪板底板,底板中间层的不锈钢片采用嵌件方式进行生产,一方面保证了产品的质量,另一方面减少了装配,保证了产品的外观。金属嵌件注射模的生产一般在立式注射机上进行,较少使用卧式注射机,如何设计在卧式注射机上生产的金属嵌件注射模,要考虑的问题很多,就不锈钢嵌件在模具中的定位问题、注射成型工艺、顶出结构系统等注射生产中涉及到的内容进行论述交流。     

超薄塑件注塑成形特性的试验研究与数值模拟

薄壁注塑成形技术具有节约材料、降低成本、减少制品重量和外形尺寸等优点,可促进移动电话等电子产品的迅速发展,特别是超薄塑件的注塑成形技术在微机电领域具有巨大的应用潜力。但随着制品厚度的减小也使注射成形难度加大,填充过程更为复杂,成形特性有待探索。设计制造出可成形超薄塑件的模具,利用正交试验方法(田口方法)进行充模试验和数值模拟技术研究各工艺参数(注射速度、注射压力、熔体温度、注射量和制品厚度等)对超薄塑件注塑成形充模过程的影响。研究结果表明,制品厚度对超薄塑件的填充起决定性作用;注射量及注射速度对超薄塑件注塑成形的填充起主导作用,提高注射速度能大幅度地提高填充率;熔体温度和注射压力相对于注射量和注射速度只起次要作用,但在填充过程中,高的熔体温度和注射压力也是必要的。     

推动块注射成型工艺分析

针对尺寸小、精度高和批量大的推动块产品,在生产过程中出现的飞边过大和欠压等成型缺陷,从材料选择、模具结构和成型条件等方面进行了分析,确定了该产品合理的成型工艺流程,即采取成型前预烘材料、试模确定3-艺参数和成型后对制品进行滚光等措施,有效地减少了推动块的成型缺陷,提高了产品的合格率,为小型塑料制品注射成型工艺的确定提供了借鉴和帮助。     

数理统计在模具生产制程能力分析中的应用

用数理统计精确度指标CPK对模具生产的制程能力进行分析.按照CPK值将模具的制程能力划分为5个等级,并以5个尺寸的32组抽样数据为例,得出CPK等级在A级时,模具生产的准确性和精密度较高,可以生产出优质产品,无需对模具和成型工艺参数做任何修改;当CPK等级不在A级时,结合准确度和精密度的情况,给出了相应的模具及成型工艺参数的整改方案.     

薄壁塑件注塑成形特性的试验研究

设计制造了一可成形薄壁塑件的模具,利用正交试验方法(田口方法)进行充模试验,研究各工艺参数(注射速度、注射压力、熔体温度、注射量和模具温度等)对薄壁塑件注塑成形充模过程的影响。研究结果表明:模具温度对薄壁塑件的填充起决定性作用,注射压力和注射量是影响薄壁塑件成形的重要工艺参数,注射速度与熔体温度之间的交互作用对薄壁塑件成形的影响显著。     

A new approach for molding multi component parts

Injection molding has gained an enormous importance over the last twenty years. This is due both to the development of sophisticated products and to the efforts being generally made to the reduction of product weight specially in automobile industry. Developments aimed at creating innovative products are expected to broaden industrial implementation of their techniques. Establishment then requires the progressive development of existing mold techniques and engineering knowledge. This paper describes a successive process for molding multi component complicated products such as door trim, instrument panel and so on. Using an analytical model, the orthogonal experiment method (Taguchi method) and numerical simulation, an optimal process for simultaneous injection molding with “core-back” and “co-injection” technique is presented to produce such innovative products. Through practical tests, this process was verified in terms of applicability.     

Warpage phenomenon of thin-wall injection molding

This study investigates warpage of electronic dictionary battery covers fabricated using thin-wall injection molding as a replacement for conventional insert molding. The primary concern is the molding window in thin-wall injection molding for acrylonitrile?Cbutadiene styrene (ABS) and polycarbonate (PC)+ABS plastics. Finally, the process parameters for thin-wall injection molding that eliminate warpage of electronic dictionary battery covers are identified. Experimental results demonstrate that the area of the molding window for ABS exceeds that for PC+ABS. Analysis of the molding window reveals that ABS is more appropriate than PC+ABS for battery covers. Low melt temperature, high injection speed, and high packing pressure eliminate battery cover warpage. Melt temperature is the most important process parameter for eliminating warpage when using both ABS and PC+ABS.     

某星载有源安装板制造工艺

星载有源安装板是星载有源相控阵合成孔径雷达中的关键结构件,其在加工和成型过程中易出现翘曲和厚度不一致等问题,对有源安装板的精度有极大影响。针对某星载有源安装板加工难度大的问题,文中从零件加工和胶粘成型方面分析其技术难点,通过对不同加工和成型方法、工艺参数、装夹方式及模具形式进行对比研究,确定了合理的制造工艺流程,优化了制造工艺参数,从而有效控制了零件的加工变形,提高了胶粘成型质量,保证了该有源安装板的成型精度。     

Multi-objective optimization of MIMO plastic injection molding process conditions based on particle swarm optimization

Determining optimal process parameter settings critically influences productivity, quality, and cost of production in the plastic injection molding industry. Selecting the proper process conditions for the injection molding process is treated as a multi-objective optimization problem, where different objectives, such as minimizing product weight, volumetric shrinkage, or flash present trade-off behaviors. As such, various optima may exist in the objective space. This paper presents the development of an experiment-based optimization system for the process parameter optimization of multiple-input multiple-output plastic injection molding process. The development integrates Taguchi’s parameter design method, neural networks based on PSO (PSONN model), multi-objective particle swarm optimization algorithm, engineering optimization concepts, and automatically search for the Pareto-optimal solutions for different objectives. According to the illustrative applications, the research results indicate that the proposed approach can effectively help engineers identify optimal process conditions and achieve competitive advantages of product quality and costs.     

透红外硫系玻璃微压印工艺的仿真研究

为了获得更好的微压印工艺填充效果,利用有限元方法研究模压工艺的主要参数压印温度、压印力和压印时间对压印效果的影响,并对工艺参数进行优化;对压印过程中不同的模具结构的应力分布进行了研究.仿真结果表明,工艺参数优化为480℃,30N,1800s后,模具的填充率达到97.2%;对不同的模具结构,有相同的应力分布区域,在模具拐...