模温机在注塑工艺中应用实例

介绍了模温机的结构、工作原理、分类和模温的作用。重点叙述了模温机在注塑聚碳酸酯、聚甲基丙烯酸甲酯、聚酰胺66/玻璃纤维、聚丙烯等的应用实例。为保证塑件质量,分别对1,2,3台模温机用法和冷水机的用法作了描述。     

新型可编程控制器在缠绕机中的应用

采用PLC控制缠绕机的优势是控制成本低、售价低、设备运行稳定、可维护性好。本文针对新型可编程控制器在缠绕机中的应用作以介绍,从缠绕控制原理出发,利用新型可编程控制器的双轴插补、高速定位功能,实现缠绕机自动控制,在缠绕过程中可实现暂停、加速操作控制,缠绕线型不受影响,从而保证产品性能稳定。     

On‐line multivariate optimization of injection molding

An auxiliary process controller was designed, implemented, and validated for on‐line process and quality optimization. The objective function included terms related to the process variation, model uncertainty, and control energy. The controller architecture relied on characterized models including both process transfer functions and principal components analysis to perform on‐line optimization in parallel with the physical molding process. New process and quality observations were input to the controller to update the models and provided new settings for the machine controller. Experimentation included characterization with a D‐optimal design of experiments followed by a validation to measure the controller's performance with respect to controller stability, extrinsic material variation, cycle time reduction, and other common manufacturing goals. In every case, the controller was able to reduce the value of the objective function while also improving the part dimensions relative to tight tolerance specifications. While characterization experiments could be costly, the use of the resulting process models greatly speeds convergence and facilitates the consideration of various cost and quality terms in the objective function. POLYM. ENG. SCI., 55:2743–2750, 2015. © 2015 Society of Plastics Engineers     

轮胎带束层裁断机裁刀装置的改进

此裁刀装置主要应用在半钢子午线轮胎带束层裁断机方面,是在现有轮胎带束层裁断机裁刀装置的基础上,对上刀压板、下刀座、弹簧压板及裁刀安装尺寸进行了改进,有效的防止了下刀座产生移位及裁刀变形。保证了上刀与下刀的正常裁切,从而发挥裁刀最大使用次数,提高工作效率,降低裁刀维护费用,提高产品质量,减少废料发生。     

基于过程模拟和随机森林模型的生物质制氢过程因素分析与预测

生物质可以替代化石燃料,减少温室气体排放,是一种有前途的可再生能源。生物质通过化学链气化制备氢气,碳化活化制备活性炭,两条工艺路线耦合可以联产绿色能源氢气和具有高附加值的活性炭,但是原材料选择和工艺参数优化成为规模化生产的主要障碍。在生物质联产氢气和活性炭工艺模型的基础上,建立高性能的随机森林预测模型,并探究生物质组分、工艺参数和过程产物对联产工艺的相对重要性。结果表明:生物质组分中的灰分、碳元素、氢元素的含量以及气体重整温度和水蒸气用量是准确预测氢气浓度和产量的重要影响因素。其中,重整温度、合成气中氢气浓度、水蒸气用量三个影响因素对氢气浓度的影响高达61%,活化剂用量、水蒸气用量两个因素对氢气产量的影响高达63%。此外,基于随机森林模型对生物质制氢过程中的因素进行分析和优化,可以实现氢气浓度达到96.8%(体积)。     

高温除湿与常规蒸汽联合干燥的试验与分析

讨论了高温除湿与常规蒸汽联合干燥过程中干燥室内空气温度、相对湿度及木材含水率的变化趋势，分析了干燥过程中除湿量及能耗的变化规律。实验结果显示，高温除湿与常规蒸汽联合干燥节能效果显著，干燥质量好。高温除湿机可以直接放在木材干燥室内部工作，无需对干燥室窑体进行改装。     

新型复合材料成型设备的进展

本文介绍了传统复合材料缠绕设备发展过程与制品应用范围,结合新型复合材料构件要求及应用特点,介绍了针对零度纵向缠绕时纤维稳定性及密实性较差开发应用纤维铺放机,针对缠绕设备低效率和低制造柔性开发应用机器人缠绕,针对缠绕工艺适应性开发应用纤维拉挤编织机。通过说明这些新型设备的应用,阐述了复合材料构件成型设备的发展趋势。     

Process optimization of ultrasonic welding

An experimental design is presented for optimizing the ultrasonic welding process in series and mass production, which requires a quantitative test method for measuring product quality. In addition to measurements of an average value, the standard deviation is also important. Small standard deviations lead to reduced scrap in production. For the optimization study, a simple welding process was chosen. Welding machines usually have adequate accuracy for a repeatable machine setting with respect to weld quality. In the cases investigated, they were not sufficiently accurate to allow for a simple quality control using the microprocessor in the machine control as a measuring device. Apart from the insufficient accuracy of the welding machines for quality control, there proved to be no correlation between weld quality and weld-time measurement under energy control.     

Calibration of cavity pressure simulation using autoencoder and multilayer perceptron neural networks

Numerical simulations of polymer melt flow behavior in cavities help predict and optimize injection molding process parameters. However, simulation and actual results may differ because of simplified mathematical models, inaccurate processing conditions, material property settings, and machine aging, among other factors. Therefore, simulated optimal process parameters cannot be directly applied in practice. This study applied machine learning to generate a virtual–actual correction model to improve the accuracy of simulation results, especially the cavity pressure profile, a key indicator of injection-molding quality for identifying ideal process parameter settings such as filling-to-packing switchover time and holding pressure. This method does not require big data for model training to enhance its practicality. Therefore, the correction model is only suitable for specific settings. A set of injection molding machines, molds, and processed materials were used for experimental verification. An autoencoder model was used to extract the features of simulation and actual cavity pressure curves. Then, a multilayer perceptron model was used to determine a relationship between simulation and actual features. The autoencoder was used to decode simulated features into cavity pressure curves. The proposed method was verified with dumbbell-shaped specimens; the correlation between simulated and actual cavity pressures was greatly improved from 81% to 98%.     

PhD Thesis Summary: Energy Efficient Multistage Zeolite Drying for Heat-Sensitive Products

Although drying takes a significant part of the total energy usage in industry, currently available drying technology is often not efficient in terms of energy consumption. Generally, the energy efficiency for drying processes ranges between 20 and 60% depending on the dryer type and product to be dried. The high energy consumption and low energy efficiency have a high environmental impact due to combustion of fossil fuel or wood used as energy sources. Moreover, the sources of fossil fuel are limited, the prices for energy increase, and the worldwide industrial energy usage rises. In this context the development of efficient drying methods with low energy consumption is an important issue for research in drying technology.     

21世纪的绿色能源

综述了绿色能源的优势、使用及前景,如太阳能、风能、生物质能、燃料电池、核能等,提出新能源的开发利用是解决能源短缺和环境污染的重要途径。     

Ölveredelung: Produkt-, Energie-, Prozeß- und Umweltdaten,Ergebnisse von Großanlagen

Oil Refining: Data on Product, Energy, Process, Environmental Pollution, and Processing Data from Large Technical Plants The need to develope new methods for processing new raw materials, meeting wider market demands, conserving energy and providing environmental protection is discussed. Physical refinement provides the means to accomplish these ends, as well as being the only practical way to overcome certain new problems such as contamination with pesticides. Modern steam distillation equipment is flexible enough to handle a wide range of energy usage, recovering the fatty acids in a directly useable form without use of lye and soapstock splitting, and with very low oil losses. Data is provided to show the extreme economy of one particular method versus other physical refining equipment, and to give information on the product quality. A formula is presented to prove the reality of the low stripping steam usage achieved in practice.     

Nonstationary convective drying of raspberries,assisted by microwaves and ultrasound

This study was conducted to investigate the drying characteristics and quality of raspberries dried in non-stationary conditions. Seven drying programs were carried out, including convective (CV) drying as a reference. The non-stationary-hybrid programs were based on continuous CV drying with intermittent microwave and ultrasound assistance. The Midilli–Kucuk model was used successfully to describe the drying kinetics of raspberry fruits. The comparison between moisture ratio, drying rate, diffusion coefficient, energy consumption, and quality analysis, showed that non-stationary-hybrid drying improves process kinetics and results in less color change, higher anthocyanin retention, and better texture profile analysis characteristics with optimal energy usage than other methods. In addition, the physical and microstructural changes occurred during different drying processes were discussed.     

催化裂化烟机振动原因分析及对策

烟气轮机是原料油催化裂化过程中重要的能量回收装置,其运行状况不仅关系到装置整体能耗水平、而且还对整套机组的安全运行有着重要的影响。文章介绍了烟机的原理和功能,并对催化裂化装置运行中引起烟机振动常见原因进行分析。通过控制工艺参数等措施,使榆炼催化裂化装置配套烟机启动初始振动值控制在3μm。     

Energy optimization during early drug development and the relationship with environmental burdens

Process development in the pharmaceutical industry is oriented to several key objectives, like yield or purity; and energy usage is normally given only a secondary consideration. On the other hand, there is a growing interest to give a greater weight to environmental factors as an integral part of the decision‐making process at the Research and Development (R&D) stages of design for drug manufacturing. Therefore, there is a need to assess the energy usage throughout the development stage, to be able to quantify the changes in the development phases and evaluate the total environmental benefits due to energy optimization. In the present work, energy life cycle information is developed to provide environmental input into process selection and development within the pharmaceutical industry. The evaluation and comparison of energy requirements and energy‐related emissions at various stages of the development process for a pharmaceutical product was conducted. It was found that the main optimization in energy usage for this specific system takes place during the pilot scale stage in the process developments (about 70% energy reduction). The reductions in energy usage are translated in even higher reduction of total energy‐related emissions (for the full‐scale processes, around 80%). It could be clearly seen that energy optimization in the early stages of process design translates into a lower level of emissions related to the use of energy. © 2000 Society of Chemical Industry     

Injection moulding process assessment by energy monitoring

Abstract

The demand for consistent and enhanced injection moulded product quality continues to rise. Modern injection moulding machines come with extensive control and measurement systems for machine control which are generally not available to the user. However, it is desired to actually measure variables that are closely related to the process itself. Sensors normally used to do this are typically invasive. However, as a result of the breadth of application of injection moulding machines, there remains a desire by the process user to be able to monitor some aspects of the process preferably in a non-invasive manner, in order to monitor, control and improve the output. In this paper, the potential for process and production measurement on injection moulding machines using non-invasive, energy measurements is presented. In addition, a comparison of electric and hydraulic injection moulding machines is given, that highlights the benefits of energy measurement to the process user. Finally, it is concluded that energy monitoring can provide a 'fingerprint' of a process, and hence can be used for product quality control.     

Process Parameters Optimization for Energy Saving in Paper Machine Dryer Section

Due to high energy consumption in the Chinese paper industry, this study considers higher-energy efficiency for the multicylinder dryer section of paper machines. A common situation in the Chinese paper industry is that energy is consumed in extensive mode. In order to improve the energy efficiency of the paper machine dryer section, deeper analysis and optimization of process parameters are necessary.

A NLP optimization method is developed for integration of steam system and air system to reduce the steam consumption and decrease the loads of centrifugal blowers in the multicylinder dryer section of a paper machine. Equality constraints of the optimization model are extracted from different process modules based on material and energy balance. Inequality constraints are from the production capacity, operating condition, etc. Two illustrative examples are presented in this paper. The results show that the optimization model is adaptive and convenient for application. For a newsprint machine, less dry air and steam are used and the energy consumption can be reduced by about 8% in the dryer section. Applied on a linerboard machine which has surface sizing, the method can reduce the energy consumption by 5.6%.     

基于PLC的FANUC 0系统数控机床常见故障诊断与排除

数控机床上的PLC主要完成加工过程中的顺序动作控制,一旦出现故障,会严重影响生产效率,延长停机时间。本文以FANUC 0系统的数控机床为例,介绍了数控机床上PLC的作用以及与外部信号的交换,详细阐述了PLC画面操作与使用的方法,基于PLC故障诊断的常用方法和思路,对FANUC 0系统数控机床常见故障进行了案例分析与处理,并总结了PLC故障诊断的注意事项。     

Comparison Between Linear and Nonlinear Prediction Models for Monitoring of a Paperboard Machine

Data from a paperboard machine were used to compare the performance of linear partial least squares (PLS) and nonlinear feed‐forward neural network (FFNN) modeling of a continuous process. Fifteen selected variables were used as input parameters to the models, while the quality class of the manufactured product was the output response. The models were validated with external data different to those used in the design of the models. Evaluation with root mean square error of prediction (RMSEP) showed that the FFNN models were better for prediction than the PLS models. For monitoring, however, the PLS models detected deviations from normal settings in the paperboard machine more sensitively than the FFNN models. It is suggested that these findings have general relevance to other continuous processes in manufacturing industries too.     

The parameters of rotary-screen printing

The amount of print paste applied through electroformed nickel rotary screens and the penetration into cotton fabric have been studied using a magnetic rod (Zimmer) sample machine. In this work the effects of the variation of screen mesh, machine settings and print paste rheology have been monitored, and in a subsequent study the effects of changes in the substrate being printed will be assessed.