Manufacturing Cost Modeling for Product Design

The process of product design is driven toward achieving design specifications while meeting cost targets. Designers typically have models and tools to aid in functional and performance analysis of the design but few tools and little quantitative information to aid in cost analysis. Estimates of the cost of manufacture often are made through a cost multiplier based on material cost. Manufacturing supplies guidelines to aid in design, but these guidelines often lack the detail needed to make sound design decisions.A need was identified for a quantitative way for modeling manufacturing costs at Motorola. After benchmarking cost modeling efforts around the company, an activity-based costing method was developed to model manufacturing cycle time and cost. Models for 12 key manufacturing steps were developed. The factory operating costs are broken down by time, and cost is allocated to each product according to the processing it requires. The process models were combined into a system-level model, capturing subtle yet realistic operational detail.The framework was implemented in a software program to aid designers in calculating manufacturing costs from limited design information. Since the information tool provides an estimate of manufacturing costs at the design prototype stage, the development engineer can identify and eliminate expensive components and reduce the need for costly manufacturing processing. Using this methodology to make quantitative trade-offs between material and manufacturing costs, significant savings in overall product costs are achieved.     

一种新的子午线轮胎活络模具设计

针对传统子午线轮胎模具设计存在的问题,提出一种新颖的一体化的弓形座与花纹块设计方案,该方案具有结构简单、体积小、质量轻等特点,实现了模具和硫化机一体设计,独立完成轮胎硫化工艺,降低了子午线轮胎模具的制造和安装成本,同时也降低了子午线轮胎的制造成本.     

铸造模拟仿真软件在汽车零件铸造工艺设计中的应用

以制动主缸为例,介绍了ProCAST软件在金属型重力铸造工艺中的应用,对制动主缸充型和凝固过程中产生的常见缺陷,进行了预测分析,通过软件的后处理模块,能直观地观测到铸造生产过程中气体包卷、缩孔等缺陷的分布,对铸造缺陷准确的预测,能有利于评价铸造工艺方案、把握铸件品质的影响因素,透彻认识铸造过程,同时有利于为铸造工艺的改进提供正确的方法,避免了多走弯路,节约了试制成本,提高了产品品质。     

Design for pressure die casting—A DFM example

The designer makes many maufacturing decisions that influence the production cost and the quality of the product. It is therefore important to ensure that the designer has a good foundation for these decisions. When talking DFM, it is important to realise that there are large differences between companies in how product design and production are carried out. The objective of the present research is to investigate and to improve the communication flow between design and production for a selected area: pressure die casting. This area is characterised by many subcontracting producers, and design and production are therefore often placed at different geographic locations. This makes an efficient communication flow even more important and it also makes the communication interface more visible. This paper discusses how manufacturing considerations are made in different design situations and how information supporting tools should be formed accordingly. Results from an investigation of DFM in a number of pressure diecasting companies and companies that design products for pressure die casting are presented. The investigation focuses on the type, the detailing level and the accessibility of the part information passing from design to production and on the manufacturing guidelines and suggestions coming from production to design.     

提高压铸模具寿命的途径研究

从压铸件的结构和压铸模具的设计、成形零件材料的选用、模具零件的加工与装配工艺、材料的热处理及压铸工艺参数的选用等方面,研究并指出了提高压铸模使用寿命的有效途径,对压铸模的设计与制造有一定的参考价值.     

Artificial neural network based model for computation of injection mould complexity

The cost of injection mould construction depends primarily on the mould complexity. The ability to estimate the mould complexity before releasing the final drawings for construction purposes will greatly help the designers to understand the implications of their design on cost. Mould complexity depends on several factors such as part geometry, parting line, materials, and number of cavities per mould. In most industries, the mould complexity evaluation is performed manually based on past experiences of mould makers. Faced with a shortage of experienced mould makers, there is a pressing need for development of computer-aided tools for mould complexity evaluation. In this study, a neural network-based design tool for computing the mould complexity index, which represents the degree of difficulty of mould manufacturing, has been developed and implemented using a 14-3-1 backpropagation network running on the CNAPS neuro-computer.     

模具制造中的并行工程研究

并行工程是保证模具交货期和质量的有效手段。本文通过分析模具制造的特点和我国模具制造企业存在的问题,从组织机构和技术手段两方面,对实施模具并行工程的可行性进行了论证,提出了模具制造并行工程的基本框架和实现模具并行工程的关键技术以及实现这些关键技术的手段和方法。这些方法已在注塑模和压铸模的设计制造中得到部分应用,取得了很好的效果。     

涂层刀具高速铣削模具钢SKD11的表面粗糙度模型预测

为有效控制和预测高硬度模具钢加工的表面质量和加工效率,通过设计正交切削试验,研究了在不同切削参数组合(主轴转速、进给速度、轴向切削深度和径向切削深度)及冷却润滑方式条件下、Ti Si N涂层刀具对模具钢SKD11(62HRC)的高速铣削。应用BP神经网络原理建立表面粗糙度预测模型,并进行试验验证其准确性。研究表明,在不同加工条件下,基于BP神经网络模型建立的涂层刀具铣削模具钢SKD11表面粗糙度模型有较好的预测精度,其预测误差在3.45%-6.25%之间,对于模具制造企业选择加工工艺参数、控制加工质量和降低加工成本有重要意义。     

浅谈汽车模具加工技术

在汽车生产制造领域,模具加工技术占有重要的地位,被称为“汽车工业之母”,汽车的发动机和底盘等重要部件都需要相应的模具。从模具加工工艺的改进角度,对部件汽车模具的加工技巧、模具加工过程中刀具的选型要求等加工工艺进行讨论,重点阐述了大型车辆模具加工的技术要求,介绍了模具的质量检测的要求,探究新时期汽车模具加工技术。     

Research on Injection Mould Intelligent Cost Estimation System and Key Technologies

The manufacturing cost of injection-moulded parts is mainly decided by the cost of the injection mould. Thus if we can ascertain the cost of the injection mould as early as possible, it will be a great contribution to an injection mould cost evaluation system and research on the economics of injected part manufacture. In this paper, related work on injection mould cost estimation has been discussed. A case-based reasoning (CBR) approach is used for evaluating the manufacturing cost of injection moulds. Case indexing, neural network-based case retrieval, knowledge-abundant case-adaptation and knowledge-absent case-adaptation strategies, and case learning are all considered. A comprehensive cost model including mould manufacturing costs, tax costs and general administrative costs is also discussed. The model is valuable for the price estimation of injection moulds. The application of the system is illustrated with an example.     

The manufacture of micromould and microparts by vacuum casting

Micromoulds are generally produced by lithography methods that often use glass and silicon wafer as substrates, with the exception of the Lithographie Galvanoformung Abformung (LIGA) method, which uses metal substrate. These fabricated moulds are then integrated into the injection moulding machine for mass production. This paper presents the use of vacuum casting methods to produce micromoulds instead of lithography. Silicone rubber is used as the mould material, which is capable of achieving nanometre surface finish. The master pattern of 1-mm diameter microgear of 60-μm teeth width and 38-μm thickness was created by standard ultraviolet (UV) lithography using SU8 photoresist. Using the vacuum casting method, ten polyurethane microgear specimens of 1-mm diameter and 38-μm thickness using the silicone rubber micromoulds have been successfully cast under vacuum conditions as a demonstration. Measurement from white-light interferometry (WLI) showed that all of the microgear cavities in the micromoulds were dimensionally accurate and consistent to the master microgear, proving that its repeatability is possible.     

浅析模具高速加工工艺及编程技术

高速加工是近年来迅速崛起的先进制造技术。随着对高速加工技术的研究不断深入,其在模具加工上的成功应用,大大改变了传统模具制造观念和制造方式,丰富了加工手段,提高了加工品质和生产效率。论文主要阐述了高速模具加工的工艺及其编程技术。     

基于位移场的涡轮叶片模具设计中的反变形技术研究

为了提高涡轮叶片的成形质量,减少模具的修模次数,提出了一种基于反变形原理的模具优化设计方法。通过使用ProCast软件对涡轮叶片进行铸造过程仿真,利用有限元模型计算涡轮叶片的精铸位移场,建立基于位移场的反变形方法,并使用该方法对模具进行优化设计,经涡轮叶片模具设计仿真试验验证,所采用的方法取得了良好的效果,可初步应用于模具的优化设计中。     

基于位移场的涡轮叶片模具设计中的反变形技术研究

为了提高涡轮叶片的成形质量，减少模具的修模次数，提出了一种基于反变形原理的模具优化设计方法。通过使用ProCast软件对涡轮叶片进行铸造过程仿真，利用有限元模型计算涡轮叶片的精铸位移场，建立基于位移场的反变形方法，并使用该方法对模具进行优化设计，经涡轮叶片模具设计仿真试验验证，所采用的方法取得了良好的效果，可初步应用于模具的优化设计中。     

电话机面壳注射模具CAD/CAE/CAM关键技术研究

模具的CAD/CAE/CAM是一项重要的模具先进制造技术。借助于该技术,可以实现模具方案的分析、优化和模具设计,缩短模具的制造周期和提高产品质量;可以对产品的成型、注射工艺参数、相应的模具结构和模具的制造工艺进行设计和优化。电话机面壳属于较薄、形状复杂和表面粗糙度要求较高的塑件。首先,在模具结构设计前应进行方案的分析,选择比较合理的浇注系统和冷却系统方案;其次,在方案分析的基础上,设计模具结构;最后,导入产品实体造型,用Mastercam数控铣床加工,在软件环境内可模拟加工,及时发现工艺失误。     

汽车发动机零件的快速制造

介绍了最适用于发动机零件制作的选区激光烧结(简称SLS)方法,并将快速成型技术与传统的铸造技术进行有效的结合形成快速铸造技术--熔模快速铸造和快速砂型铸造,以快速制造复杂金属零件.     

泵叶轮熔模铸造的关键技术探索

将熔模铸造技术应用在叶片制造上,可以解决传统砂型铸造工艺的诸多弊端。从二维水力模型图出发,采用Pro/E软件就叶片三维造型、叶片与前、后盖板蜡模定位结构的设计以及叶片压型设计、制造等关键问题进行了分析和探讨。     

消失模铸造工艺在密集小孔平板类铸件中的应用

密集小孔平板铸件的普通砂型铸造工艺十分复杂,而且合格率低,铸件难以清理。介绍采用消失模铸造工艺生产带有密集小孔平板类铸件的工艺方法。实践表明,该法具有独特优越性,生产出的孔板变形小、表面光洁;孔的内壁光滑、棱角清晰。     

基于压铸模本体的领域概念自动抽取方法研究

概念是本体的核心,人工抽取领域本体概念存在工作量大、速度慢、维护及更新困难等问题。以压铸模领域概念抽取为例,通过分析领域概念分布特点,结合中文分词技术在自然语言处理上的应用,考虑领域概念相关性,提出了一种基于概念相关性的本体概念抽取方法。选取部分压铸模领域文本作为实验样本,利用ICTCLAS软件分词,接着合成词语并进行相关性判断,经领域专家验证得到压铸模领域概念。实验结果表明,该方法提高了压铸模领域概念抽取的效率和准确度,为领域本体高效构建提供了理论和实践基础。     

低压铸造薄壁板件的流动与传热耦合数值模拟

采用 VOF法处理自由表面 ,达西源项法处理固 -液两相区流动 ,开发了铸造过程流动与传热耦合数值模拟软件。通过对流场及温度场分别采用不同的计算域和时间步长 ,大大提高了计算效率。利用该软件模拟了一薄壁板件的低压铸造过程 ,并进行了实验验证。数值模拟结果表明 ,对薄壁件而言 ,充型过程的流动对铸件初始温度分布影响较大 ,但充满后的残余流动对温度分布影响较小