Unit process energy consumption models for material removal processes

Economical, environmental and legislative drivers have recently raised the awareness of energy consumption and the associated environmental impact of manufacturing processes. A reliable prediction of unit process energy consumption will enable industry to develop potential energy saving strategies during product design and process planning stages. This paper presents an empirical model to characterize the relationship between energy consumption and process variables for material removal processes. The methodology has been tested and validated on a number of turning and milling machine tools. The model presented predicts the energy consumption of manufacturing processes with an accuracy of more than 90%.     

Conceptual manufacturing system design based on early product information

This paper presents a new approach for the conceptual design of manufacturing systems based on early product information supported by model-based systems engineering. The approach consists of three parts: First, an integrated process model for product design and manufacturing systems planning, second, a systematic method for the conceptual design of manufacturing systems based on early product information, and third, a modelling approach based on a common design language for the collaboration between product design and manufacturing systems planning. The proposed approach is validated using an example from the automotive industry.     

A production planning system to continuously integrate the characteristics of reconfigurable manufacturing systems

Operation in a dynamic environment requires companies to constantly adapt their manufacturing systems to stay competitive. One approach to manufacturing is the use of reconfigurable manufacturing systems (RMS). Current production planning approaches cannot model and realize the production-side adaptions available in RMS. In this article a novel planning system for modeling that continuously integrates the key characteristics of RMS in production planning and control (PPC) is presented. First, the challenges for production planning using RMS are defined. A feasible planning system is then presented, based on modeling and specification approaches, followed by a planning method to realize capacity scalability and functionality changes in planning processes. Finally, a prototypical application is outlined and the planning system is evaluated with the help of different production scenarios. The application results demonstrate the feasibility of the planning system as well as the potential improvement of typical key performance indicators in manufacturing.     

制造业信息系统演化及动态企业建模的研究

分析了人类社会制造业分划阶段与生产特性，指出信息技术、信息系统将对制造业产生使能作用。研究了企业资源规划(ERP)、动态企业建模(DEM)的基本特性、软件功能、体系结构及其对制造业的影响；最后给出制造业信息系统的发展态势。     

不锈钢管的需求和生产技术发展概况

介绍了近年来我国不锈钢管的发展情况,重点分析了油气钻采、石油化工、化工、火电站、核电站等能源开发和制造业用不锈钢管的特点、种类、需求数量及市场前景。比较了不同生产工艺生产不锈钢管的特点。揭示了无缝和焊接不锈钢管生产工艺技术的发展趋势。     

重型机械企业信息化中的物料编码解决方案

制造企业实施信息化是以现代信息技术改造传统工业的有效手段。企业信息的集成是实施信息化的基础。本文作者在西安冶金机械有限公司实施ERP系统的实践中,在设计和工艺阶段有机整合现有的CAD和CAPP功能,通过解决物料编码的添加的问题,为重型机械制造企业实施ERP系统提供了有益的借鉴和指导。     

分布式制造系统的动态物流规划与集成策略

网络技术与信息技术的发展使制造系统显现出了一些新的特点,在物流规划与集成方面应有别于传统的单个企业的情况.文章在分析网络环境下制造系统应解决的一些问题基础上,探讨了全局物流规划、局部物流调整以及系统物流协同等离散制造系统进行分布式物流规划的策略.并基于物流信息分析了分布式制造系统中物流活动的运行控制模式、物流信息的协作模式以及基于物流活动的集成机制,从而实现分布式系统不同决策主体之间的协同与基于信息的集成.     

Assembly and Disassembly Processes in Product Life Cycle Perspectives

Industrial companies change the paradigms of business operations from optimisation of manufacturing processes to optimisation of products life cycles in order to activate the value of products, taking into account the potentials of product services in all phases of each product's life. From design to the end of their life capital intensive products, like manufacturing or assembly systems, are linked to a manufacturer network by global communication systems. This network allows special services even in the phases of usage and recycling. For this new paradigm it is necessary to develop strategies, methods and technologies to manage the business processes and the information and knowledge required in all phases of a product's life and to industrialise the processes of design, assembly, usage, service and remanufacturing by disassembly and recycling. It is the objective of this paper to define the processes for management of life cycle with a focus on assembly, service and disassembly of capital intensive products.     

Modelling and Control of Production Systems based on Nonlinear Dynamics Theory

Today's highly dynamic market with its rapid changing demand requires highly dynamic order processing in very flexible production systems. Most conventional production planning and control methods do not support such fast-moving activities. A dynamical approach is introduced for modelling and control of production systems. It was developed from concepts of the Nonlinear Dynamics Theory. Manufacturing processes as well as planning and control mechanisms are seen as one unit toward the establishment of a dynamical system. The dynamical approach includes an analysis of the dynamic behaviour of the production system as well as the control of the manufacturing process by a continuous adjustment because of changes or disturbances in the environment or in the production system itself.     

关于新一代钢铁制造流程的命题

21世纪钢铁工业面临的是一种最新形式的综合性挑战,它包括了经营成本、产品质量与性能、生产效率与合理规模、能耗与过程排放、环境与生态等多目标群优化.这些挑战,主要应从钢厂生产流程整体优化来解决.新一代钢铁制造流程的研究内涵应包括：高效率、低成本的洁净钢生产平台技术;工序间动态-有序运行的“界面技术”;流程工程集成技术;系统、高效的能源转换技术;废弃物再资源化技术;产业链接技术;流程物理模型与虚拟现实技术.总之,要通过钢铁制造流程的研究开发,拓宽钢厂生产流程的功能——即钢铁产品的制造功能、能源转换功能和废弃物再资源化功能-增强市场竞争力和可持续发展能力.     

Design space computation based on general design theory applied to knowledge formulation in simulation-based production planning

Digitalization is crucial for increasing the productivity of manufacturing systems and processes, where model-based systems engineering is a key engineering discipline to support related design and planning activities. However, knowledge used in these activities is not sufficiently captured through exhaustive simulation-based searches on design spaces. This study proposes a design space model based on General Design Theory to express such knowledge using the properties of topological spaces. A simulation-based production planning case study demonstrates computation of a design space from simulation experiments using inductive and deductive reasoning, and formulation of complex design options for production plans to meet performance criteria.     

Modeling and analyzing logistic inter-dependencies in industrial-enterprise logistics

Despite spending considerable effort on the design and operation of production planning and control systems, manufacturing companies experience logistic performance deficits. Frequently, these are due to inconsistencies between the logistic objectives the companies set themselves and the planning and control actions they take to achieve the objectives. Analytical models of logistic processes are applied to obtain a better understanding of the process behavior. Models of this type often do not succeed in clearly establishing the relationships between the planning and control actions the processes can take and the logistic performance measures. The paper presents qualitative influence models that identify these interdependencies within individual logistic processes and across process boundaries. Coupled with a qualitative evaluation of the effects of the planning and control measures on the logistic performance of the processes, the models facilitate objective-oriented logistic performance management.     

A discrete-event simulation approach to predict power consumption in machining processes

Whereas in the past the sustainable use of resources and the reduction of waste have mainly been looked at from an ecological point of view, resource efficiency recently becomes more and more an issue of cost saving as well. In manufacturing engineering especially the reduction of power consumption of machine tools and production facilities is in the focus of industry, politics and research. Before power consumption in machining processes can be reduced it is necessary to quantify the amount of energy needed, to identify energy consumers and to determine the available degrees of freedom for an optimization. Simulation can be an adequate alternative to the measurement of power consumption during machining operation. However, many of the available simulation methods are not suitable for this task. This paper describes an approach based on the discrete-event simulation, which is known mainly from the simulation of logistical systems. It has been adapted to model machining operations and to generate workpiece-specific power consumption profiles and energy footprints. Two-axis turning in a CNC machining centre is shown exemplary. The aim is to provide a basis for further applications such as the simulation, comparison and optimization of power consumption in process chains and production systems in combination with logistical models.     

Model-based predictive force control in milling: determination of reference trajectory

Today, powerful process simulation tools allow an offline process planning and optimization of metal cutting processes. The quality of the optimization strongly depends on the model and its parameters. Real cutting processes are influenced by uncertainties such as tool wear status or material properties, which are both unknown. To overcome this limitation, sensors and process control systems are used. Model-based Predictive Control (MPC) was developed in the 1970s for the chemical process industry. This control method was found to be very suitable to control complex manufacturing processes such as milling processes. Using MPC in metal cutting processes allows considering technological boundary conditions explicitly. Adapting the feed velocity and thus the process force increases the productivity and process stability in milling. A core element of the MPC is the use of a reference trajectory representing the time-dependent set point value in the optimization procedure. The tool path information, however, is given position-based. Thus, calculating the reference trajectory is not trivial and strongly influences the control quality. This paper presents two methods for determining the reference trajectory. The first method is based on an adaptive signal filter. For the second method the MPC is extended to a two-layer MPC: the first layer calculates an optimal reference trajectory; the second layer controls the machine tool.     

Tool optimization for high speed grinding

Vitrified bonded cBN grinding wheels catches on for batch production especially in the automotive industry for components of power trains. In pursuit of higher productivity with steady quality the optimization of manufacturing processes and tools are getting more relevant. In this contribution potentials and challenges of structured grinding tools for the optimization of grinding processes are discussed. Technological investigations with structured and non-structured vitrified bonded cBN grinding wheels were carried out and the results of varying setting parameters were analyzed. The main aspects of interest for these studies were the detection of possible coolant savings and phenomena of vibrations, the reduction of the thermal damage of the workpieces as well as the influence on the workpiece roughness and the grinding wheel radial wear. The experiments show the potentials of structured cBN grinding wheels for roughing and finishing in cylindrical plunge grinding processes. But there are some basic requirements for the geometry of the structures especially due to the vibrations of the grinding process. For the roughing tests the adequate structured abrasive layers show less grinding forces and thermal damage of the workpiece. For finishing processes the results show comparable values of roughness and waviness referring to non-structured grinding wheels. In addition, a limit for suitable grinding wheel structures in conjunction with the setting parameters could be identified that offers valuable clues for the dimensioning of structured abrasive layers even for non-circular grinding processes.     

Environment protecting hydrometallurgical processes associated with the manufacture of some tungsten based products. I. The manufacture of ammoniumparatungstate (APT)

Reviewing the fundamental processes adopted for ammoniumparatungstate (APT) manufacture the main byproducts, wastes generated in the processes, have been summarized with their environmental impacts.

A process based on the electrodialytical recovery of NaOH for the elimination of the salt byproduct generated in the largest quantities was outlined, as were the main aspects to be taken into account at the large-scale industrial implementation.

The present stage of the development and implementation of an APT production line for the processing of typical scraps in the lamp filament industry is shown as well as the oxidizing and dissolving process of compact and lumpy tungsten alloy scraps (Cu---W, Fe---Ni---W) and hard metal scraps (Co---WC, Co---WC---Ta(Nb)C---TiC).

Some up-until-now unexploited potentials were sketched, being desirable from scientific and engineering aspects for the development of more efficient and up-to-date ATP and other tungsten-intermediate manufacturing processes or process operations from a wide variety of raw materials.     

Methodology for planning and operating energy-efficient production systems

Planning and operating energy-efficient production systems require detailed knowledge on the energy consumption behaviour of their components, energy consumption of production processes, and methods to evaluate design variants. In this paper, the EnergyBlocks methodology for accurate energy consumption prediction is introduced. The methodology is based on the representation of production operations as segments of specific energy consumption for each operating state of the production equipment. Modelling any process chain is possible by arranging the segments according to the production programme. The application of the methodology is demonstrated on the manufacturing of a swash plate expander.     

The Korea Advanced Manufacturing System (KAMS) Project

The Korea Advanced Manufacturing System (KAMS) is one of the Highly Advanced National (HAN) Projects planned to achieve significant technological advances in Korea. The aim of this project is to create new processes and technologies for managing and integrating manufacturing systems. The key to sustaining economic growth and surviving global competition is to develop advanced manufacturing systems technology. The Korea Institute of Industrial Technology (KITECH) began this project in 1992 with support from the Ministry of Trade, Industry and Energy and the Ministry of Science and Technology. The project is divided into three phases, each phase consisting of project groups which include several research projects. The main project groups are ‘next-generation machining system' and ‘assembly and inspection system for electronic products'. The names of research projects are listed, and brief explanations are also introduced in this paper. The KAMS Project is expected to result in many benefits for manufacturing industry. The increase in productivity and system accuracy, and reduction in lead-time, will give renewed vitality to Korean manufacturing industry.     

人工神经网络在过程工业中的应用

当前,集过程实时监测、故障诊断、模拟、优化、控制以及调度等各层次功能于一体的过程工业生产过程综合自动化成了过程工业界和学术界共同关注的热点之一.与离散产品的制造业相比,由于流程型工业过程具有强非线性的特点,给实现流程工业综合自动化造成很大的困难,因此必须引入新的思路,开发新的方法.人工神经网络是一种模拟人类思维活动的并行分布式的信息处理系统,可用于映射任何连续函数及进行模式识别,同时还具有自学习功能,实现知识的自动获取,自20世纪90年代以来已在过程系统工程领域内受到广泛的瞩目.重点讨论了人工神经网络在过程系统建模、故障诊断以及在线优化等方面的应用,以展示这种方法在流程工业综合自动化中的良好应用前景.     

The selection of tools and machines on web-based manufacturing environments

Tools and machines selection is one of the most important activities in process planning. Computer-aided tool selection (CATS) has been a vital element in Computer-aided process planning (CAPP) systems. However, the selection of tools and machines is a dynamic activity between planning and scheduling. Most CAPP systems focus on the generation of static process plans via incorporated manufacturing knowledge and they are not flexible to connect with existing manufacturing resources. In addition, there is an increased demand for CATS to frequently communicate with design in manufacturing environments for manufacturability evaluation. This paper discusses the selection of tools and machines on Web-based manufacturing environments. It helps existing CAPP systems to generate realistic and economical process plans, and lets designers efficiently undertake manufacturability evaluation. In particular, the machine selection incorporated with tool selection can generate extended strategies for economical production. An example is presented to illustrate the method proposed.